Introduction to: Evolution-Involution Slideshow

Evolution

Where did we come from?...Where are we going?

Civilized Homo Sapiens

Selection pressure in a Post-Darwinian World. Biorevolution; Human evolution is about to accelerate and BLTC wants to insure that designer babies and huma cloning evolve via best practice of genetic engineering. Selection pressure isn't going to slacken. On the contrary, We're on the eve an era of unnatural or artificial selection- a diffrent kind of selection pressure, but a selection pressure

The Tunguska Air Blast

A century ago, on June 30, 1908, an asteroid or comet hurtled into Earth's atmosphere and exploded over Siberia, flattening 2,000 square kilometers of forest. This is simply the latest incident where bodies from outer space (in this case probably a small comet) have impacted life on Earth. There have been five major recorded episodes- from both internal (supermassive vulcanism and climatic upheaval) and external (asteroid impacts and gamma ray blasts) that have caused mass extinctions (up to 90% of Earths entire biota during the Permian-Tertiary 'Great Dying'). The first struggles for life to establish may have begun as early as a few million years after Earth solidified into a planet 4.5 billion years ago with repeated extinctions happening during the Pre-Cambrian- so no fossil evidence is preserved.

Humans as Biological Collective

Early life forms were prokaryotic cells that evolved into nucleated eukaryotic cells that assimilated mitochondria to provide chemical energy in a symbiotic union with their host. We- along with plume worms, fruit flies and bats are direct descendants of that co-evolution between the microbes--organisms that live within and upon our host bodies that effect the dermal, digestive, immune and other systems vital to our health and survival. Our bodies harbor 100 trillion bacterial cells, outnumbering our human cells 10 to one. A symbiotic perspective sees ourselves as hosts over an evolutionary timescale of billions of years in which our cells carry an ancient stamp of symbiosis in the form of mitochondria. In some ways, we’re an amalgam and a continuously evolving collective.

Homo sapiens sapiens Races

Race refers to the classification of humans into populations or groups based on various factors such as culture, language, social practice or heritable characteristics. As a biological term, race describes genetically divergent populations of humans that can be marked by common phenotypic and genotypic traits. This sense of race is often used (not without controversy) in forensic anthropology analyzing skeletal remains, biomedical research, and race-based medicine but has no official biological taxonomic significance.

Lakota Ghost Dance

The Ghost Dance religion (or movement) was a last vestage of an Amerindian tradition in a continuum that had begun in North America over 15,000 years ago. It was an attempt to answer the subjugation of Native Americans by the U.S. government by revitalizing traditional culture and to find a way to face increasing poverty, hunger, and disease, all representing the reservation life of the Native Americans in the late nineteenth century. The Ghost Dance originated among the Paiute Indians around 1870, however, the tide of the movement came in 1889 with a Paiute shaman Wovoka (Jack Wilson). Wovoka had a vision during a sun eclipse in 1889. In this vision he saw the second coming of Christ and received warning about the evils of white man. The messianic religion promised an apocalypse that would destroy the earth and the white man - then the earth would be restored to the Native Americans along with the return of the buffalo.

Portraits of Amerindians

Indians Hunting Buffaloe on Horseback

Extracts from the journal of Osborne Russell - a trapper on the far-western American frontier 1834 to 1843. Snake Indians - The appellation by which this nation is distinguished is derived from the Crows but from what reason I have never been able to determine They call themselves Sho-sho-nies. Their country comprises all the regions drained by the head branches of Green and Bear rivers and the East and Southern head branches of Snake River The Buffaloe is already a stranger, altho so numerous 10 years ago, in that part of the country which is drained by the sources of the Colerado, Bear and Snake Rivers and occupied by the Snake and Bonnack Indians. The Snakes who live upon Buffaloe and live in large villages seldom use poison upon their arrows either in hunting or war - They are well armed with fusees (fusee - a gun - editor) and well supplied with horses they seldom stop more than 8 or 10 dys in one place which prevents the accumulation of filth which is so common among Indians that are Stationary. Their lodges are spacious neatly made of dressed Buffaloe skins, sewed to gether and set upon 11 or 13 long smooth poles to each lodge which are dragged along for that purpose.

Buffalo Hunt

Centered in what is now Utah, the area of the Colorado Plateau and eastern Great Basin was first settled (9,000 BC to about 5,500 BC) by Paleoindian - big and small game hunters, collectors, foragers. About 5,500 BC to about 1000 BC archaic indians adapted increasingly to agriculture. Originally considered to be an inferior, out-back branch of the well studied Anasazi culture, most archaeologists now believe that between 2500 and 1500 years ago, the existing groups of hunter-gatherers gradually developed into the Fremont Culture with a lifestyle of hunting/gathering and corn horticulture. They left a record of a distinctive pictographs and petroglyphs, throughout their range. The Three King's panel of the Fremont Indians near Vernal, Utah is regarded as the finest Indian petroglyph panel in the world.

Butchering Bison

Clovis people (13,500 to 13,000 ya) were considered to be the ancestors of all the indigenous cultures of North and South America. However, this majority view has been contested over the last thirty years by several archaeological discoveries. Radiocarbon dating of the Monte Verde site in Chile place Clovis-like culture there as early as 13,500 years ago and remains found at the Channel Islands of California place coastal Paleoindians there 12,500 years ago. This suggests that the Paleoindian migration could have spread more quickly along the Pacific coastline, proceeding south, and that populations that settled along that route could have then begun migrations eastward into the continent. sculpture by Mike O'Brien, and a background scene painted by Nola Davis, courtesy Texas Parks and Wildlife Department.

Clovis Deer Hunters

New studies of genetic samples from native New World populations (from Alaska to Brazil) show they all share a unique allele at a specific microsatellite locus that is not found in any Old World populations (except Koryak and Chukchi of western Berengia), which implies that all modern Native Americans descended from a single founding population that was the result of migration of a narrow North Asian population. This is further supported by ancient DNA studies showing that Late Pleistocene Paleoamerican carried the same haplogroups (and even sub-haplogroups) as modern Native groups. Dogs are depicted whose ancestors must have accompanied the first humans into America- having co-evolved with Homo sapiens from wolves some 135 Kya.

North American Short-faced Bear

Arctodus simus- the giant short-faced bear has just chased two wolves away from their kill, a steppe bison calf. As the bear eats, the wolves wait, hoping to get back to their prey. The giant short-faced bear was the largest and perhaps the fiercest of the Ice Age land carnivores of North America. It appears to have specialized in scavenging, driving other predators away from their fresh kill.

Giant Short-Faced Bear

Arctodus simus, also known as the giant short-faced bear, is an extinct species of bear. It was native to prehistoric North America from about 800,000 years ago, and became extinct about 12,500 years ago so the earliest Clovis people may have confronted this fearsome predator. It is one of the largest bears in the fossil record and was among the largest mammalian land predators of all time. http://en.wikipedia.org/wiki/Arctodus_simus According to the still-debated Settlement of the Americas, a migration of humans from Eurasia to North America took place via Beringia, a land bridge created from falling sea levels which which began about 60,000 - 25,000 years ago, that connected the two continents across what is now the Bering Strait. The minimum time depth by which this migration had taken place is confirmed at 12,000 years ago, with the earliest period remaining unresolved.

Kennewick Man

Sometime around 15,000 years ago, the new theory goes, coastal Asian groups began working their way along the shoreline of ancient Beringia - a route labled 'the kelp highway'. Kennewick man may belong to an ancient population of seafarers who were America’s original settlers. They did not look like Native Americans. The few remains we have of these early people show they had longer, narrower skulls with smaller faces. These mysterious people have long since disappeared. Judging from the shape of his skull and bones, his closest living relatives appear to be the Moriori people of the Chatham Islands, a remote archipelago 420 miles southeast of New Zealand, as well as the mysterious Ainu people of Japan - Just think of polynesians.

Las Palmas Clovis Woman

A scientific reconstruction of an ancient woman known as La Mujer de las Palmas, based on the skeletal remains of a female who lived between 10,000 and 12,000 years ago. Experts reconstructed what the woman may have looked like based on the remains found in 2002 in a flooded sinkhole cave near the Caribbean resort of Tulum, Mexico. Anthropologist Alejandro Terrazas says the reconstruction resembles people from southeastern Asia areas like Indonesia, even though experts had long believed the first people to migrate to the Americas where from northeast Asia.

This undated photo taken at the France-based Atelier Daynes in Paris, released on Friday, July 23, 2010, by Mexico's National Institute of Anthropology and History, shows a scientific reconstruction of an ancient woman known as La Mujer de las Palmas, based on the skeletal remains of a female who lived between 10,000 and 12,000 years ago in Tulum, Mexico. Experts reconstructed what the woman may have looked like based on the remains found in 2002 in a sinkhole cave near the Caribbean resort of Tulum, Mexico. Anthropologist Alejandro Terrazas says the reconstruction resembles people from southeastern Asia areas like Indonesia, even though experts had long believed the first people to migrate to the Americas where from northeast Asia. (AP Photo/ Mexico's National Institute of Anthropology and History)

Naia of Hoyo Negro

New finds, theories, and genetic discoveries are revolutionizing our understanding of the first Americans. The first face of the first Americans belongs to an unlucky teenage girl who fell to her death in a Yucatán cave some 12,000 to 13,000 years ago. Her bad luck is science’s good fortune. The story of her discovery begins in 2007, when a team of Mexican divers led by Alberto Nava made a startling find: an immense submerged cavern they named Hoyo Negro, the “black hole.” At the bottom of the abyss their lights revealed a bed of prehistoric bones, including at least one nearly complete human skeleton.

Huaorani Tribe

One of the indigenous Amazonian tribes in Ecuador, possibly descended from an initial wave of immigration that occurred around 25 Kya during the Beringian glacial refugium that created a land bridge between Siberia and Alaska - resulting is a swift peopling of the Americas that in a space o 10 K years spread as far south as Monte Verde in Chile. In the last 40 years the Huaorani have shifted from a hunter-gather, stone-age culture to live mostly in permanent settlements. Conclusions from studies of mitochondrial genomes haplogroup suggesting that all indigenous Amerindian are part of a single founding East Asian population are questioned by fossil evidence from Brazil's Lagoa Santa region. Subsequent immigrants around 10 Kya may have displacerd earlier populations in North America who themselves were displaced by later arrivals -the ancestors of modern native-American indians.

Luzia of Lagoa Santa

At least two distinct groups of early humans colonized the Americas, a new study says. Anthropoligists studied 81 skulls of early humans from Brazil's Lagoa Santa region and found them to be different from both modern and ancient Native Americans. One skull discoverd at a site in the state of Minas Gerais called Lapa Vermelha was given the name Luzia. The 11,000-year-old remains suggest that the oldest settlers of the Americas came from different genetic stock than more recent Native Americans. Modern Native Americans share traits with Mongoloid peoples of Mongolia, China, and Siberia but researchers found many skulls from Brazil appear much more similar to modern Australians, Melanesians, and Sub-Saharan Africans.

Standoff

Sabertooth versus Dire Wolves in southern California 13,000 years ago.

The La Brea Tar Pits in California are the most famous of many tar pits around the world that have preserved the fossil remains of extinct megafauna from the last ice age more than 30 Kya. The only human evidence recovered so far- is the crushed skull of a female dating to 9 Kya. Radiocarbon dating has shown the Clovis period to range from 13,300 to 12,800 calendar years ago, giving the culture only several hundred years to reach the tip of South America. The Clovis-first model says it would have taken anywhere from 700 to 1,000 years but archaeological sites in South America have yielded the same dates. It now seems the peopling of the Americas was not a singular event but instead- people arrived at different times and took different routes and potentially came from different places.

California Before Humans

Camels, tapirs, horses, and early llamas roamed southern California 20,000 years ago, but none of those species—not even the horses—survived there after the end of the Ice Age.

Clovis Mammoth Hunters

Because of the much greater similarity to stone point in France and the much greater concentration of their sites around the Chesapeake area it's possible Clovis populations first established along the Eastern seaboard. Sediment containing magnetic spherules, nanodiamonds and fullerenes widespread across N. America but with highest concentration in the Chesapeake suggest an impact event triggered the Younger Dryas Climatic Catastrophe creating a 10-degree drop in temperature and a 1000-year dust storm that wiped out 80% of the mega fauna along with all but a barely sustainable remnant of Clovis. Migration away from their devastated hunting grounds in the East- they may have eventually interacted with Folsum people spreading over the western regions.

Bison Hunters

Bison became the dominant mega fauna to survive the Younger Dryas Climatic Catastrophe and replaced the Columbian Mastodon as a stable in the diet of Clovis culture. After several thousand years, the Clovis may have exchanged technology with the N, Asian populations from Beringia during a several thousand-year interaction eventually dying off, leaving the Folsom the dominant culture who adopted less refined spear point technology to become the direct ancestors of all modern Amerindians.

Crossing Beringia

Genetic evidence supports the theory that ancestors of Native Americans crossed into Beringia and lived for 15,000 years on the Bering Land Bridge between Asia and North America until the last ice age ended. But genetic evidence shows there is no direct ancestral link between the people of ancient East Asia and modern Native Americans. A comparison of DNA from 600 modern Native Americans with ancient DNA recovered from a late Stone Age human skeleton from Mal'ta near Lake Baikal in southern Siberia shows that Native Americans diverged genetically from their Asian ancestors around 25,000 years ago, just as the last ice age was reaching its peak.

Siberian Hunters - Pleistocene

North Asian hunter-gatherers are thought to have migrated over the Beringia land bridge and become the first humans to enter N. America. The fact that spearheads recovered from Pleistocene sites in Siberia are made of bone (with a series of stone chips fitted into a slot along one edge) and have no resemblance to the finely napped Clovis stone points that mark the earliest human presence throughout N. America- some scientists have proposed that the first migration was not via the Beringia land bridge but by Solutrean paleo seal hunters traveling in primitive boats (wood-framed covered in animal hide) along the southern edge of the Laurentide ice sheet that provided a sustainable migration route from the European continent to N. America.

Paleo Caribou Hunters

At the very end of the Ice Age, around 12,000 to 14,000 years ago, after several earlier migrations, ancestral Na-Dene speakers may have moved across the Beringia land bridge, pursuing thin-skinned animals like the caribou, using their microblade-barbed hunting weapons. Most theories believe that northern peoples came from Central Asia, with Uralic peoples migrating to the Northwest and Altaic peoples to the Northeast between 8,000 and 12,000 years ago. Over time, they spread south and west to Kodiak Island, to the Pacific Northwest Coast, far into the interior (where they became the Athabaskans), and later, some of them split off and moved southward to become the modern-day Navajos and Apaches. At some later time (anywhere from as much as 10,000 to 7,000 years ago), a second migration brought the maritime-oriented ancestors of the Aleuts and Eskimos to Alaska, replacing earlier Paleo-Arctic people. Recent archaeological work in the Sakha Republic of Russia has revealed sites on the Le a River that are arguably 35,000 years old. Such discoveries have caused scientists to reconsider the possibilities of even earlier human life in the Siberian North.

Woolly Mammoth

A 2008 DNA study showed there were two distinct groups of woolly mammoths: one that went extinct 45,000 years ago and another one that went extinct 12,000 years ago. The two groups are speculated to be divergent enough to be characterised as subspecies. The group that went extinct earlier stayed in the middle of the high Arctic, while the group with the later extinction had a much wider range.[64] Recent stable isotope studies of Siberian and New World mammoths have shown there were also differences in climatic conditions on either side of the Bering land bridge, with Siberia being more uniformly cold and dry throughout the Late Pleistocene.[65] During the Younger Dryas age, woolly mammoths briefly expanded into north-east Europe, whereafter the mainland populations became extinct. A 2008 genetic study showed that some of the woolly mammoths that entered North America through the Bering land bridge from Asia migrated back about 300,000 years ago and had replaced the previous Asian population by about 40,000 years ago, not long before the entire species went extinct.

Columbian Mammoth

The shoulder height of the Columbian mammoth reached 13 ft, and it weighed up to about 10 tonnes, which is equal to the weight of 130 adult humans. This is larger than modern African elephants and the woolly mammoth, which reach about 9–11 ft. Columbian mammoths had a high, single-domed head and a sloping back with a high shoulder hump; the shape resulting from the spinous process of the vertebrae decreasing in length from front to back. These features were not present in juveniles, which had convex backs like Asian elephants. Excavations at the La Brea Tar Pits in Los Angeles, California, have yielded fossils from several Columbia mammoths that became stuck in asphalt puddles that seeped to the surface of the pits. The Columbian and woolly mammoths both disappeared during the late Pleistocene and early Holocene, alongside most of the Pleistocene megafauna, during the Quaternary extinction event, which began 40.000 years ago, and peaked between 14.000 and 11.500 years ago.

Spark of Civilization

11,600 years ago, hunter-gatherer's urge to worship sparked civilization. Organizing to build monumental stone temples was likely the trigger that began the Neolithic Revolution that led to argriculture, plant and animal domestication and permanent settlements.On a remote hilltop in southern Turkey known as Gobekli Tepe, archaelogists discovered a paleolithic complex of monumental temples featuring massive limestone pillars - the largest 18 feet tall and weighing 16 tons. The architecture is vaguely reminiscent of Stonehenge but created 7 millennia earlier than the Great Pyramid of Giza and is made not with roughly hewn blocks but from cleanly carved pillars representing sophisticated stylized anthropomorphic forms splashed with bas-reliefs of a variety of recognizable animal totems. Subsurface scans at the site reveal an assemblage of perhaps 18 unexcavated temples that were consecutively built and buried over a period of a little more than a thousand years. The site is evidence that organized religion could have come before the rise of agriculture and other aspects of civilization. Twenty years ago scientist believed civilization was driven by ecological forces - what we are learning is that civilization is a product of the human mind.

After Cro-Magnon

The term Cro-Magnon doesn't refer to a particular taxonomy or even a particular group located in a particular place. The word is not precise enough, and so most paleontologists prefer to use Anatomically Modern or Early Modern Humans. The term anatomically modern humans (AMH) or anatomically modern Homo sapiens (AMHS) refers in paleoanthropology to individual members of the species Homo sapiens with an appearance consistent with the range of phenotypes in modern humans. Anatomically modern humans evolved from archaic Homo sapiens in the Middle Paleolithic, about 200,000 years ago. The emergence of anatomically modern human marks the dawn of the subspecies Homo sapiens sapiens, i.e. the subspecies of Homo sapiens that includes all modern humans.

Magdalenian Culture

The most recent Paleolithic culture (15,000-8000 B.C.); it superseded the Solutrean culture and preceded the Azilian culture of the early Mesolithic period. At the time of the transition to the Magdalenian culture, the Solutrean flint points and the technique of retouching used in the working of flint were disappearing. Various flint gravers, awls, and scrapers predominated. The working of bone became highly developed. Harpoons, spearheads, dart points, spear-throwers, batons de commandement, needles, and other implements made of reindeer antler, of ivory (from mammoths), and of bone became widespread. Engraved representations on antler and bone are typical, as are sculptures from antler, ivory, and bone and monochrome and polychrome drawings on the walls and ceilings of caves. In a later stage of the Magdalenian culture, small geometrically shaped flint tools became widespread, representing a gradual transition to the geometric microliths. The Magdalenian hunters primarily lived in caves; sometimes they lived in dwellings made of bones and skins. They often led a nomadic existence, pursuing herds of reindeer.

Cro Magnon Burial Ceremony

A historically key challenge to evolutionary psychology has been how altruistic feelings and behaviors could have evolved when the process of natural selection is based on competition between different genes. Theories addressing this have included kin selection and reciprocal altruism. Neanderthals living in Shanidar Cave in the Zagros Mountains of Kurdistan in Iraq. 60,000 to 80,000 years ago buried their dead, and may have had burial ceremonies for the dead. Fossil evidence also shows that members of the group cared for one another: Injuries found in the fossilized bones of a man 35 to 45 years of age show serious injuries to the head and to a foot. Despite the severity of the injuries, the man's bones show signs of healing, suggesting he was cared for by others while he was injured.

Pleistocene Campsite

Archaelogical evidence indicates human dependence on mammoth hunting was widespread for many thousands of years throughout eastern Europe. Mammoth bone dwellings in Mezhirich, Ukraine, and in the Dneiper River valley of Russia and Ukraine date between 15,000 and 27,000 years ago. Later the culture extended into the Clovis Culture in North America. Homo erectus is known to have consumed mammoth meat as early as 1.8 million years ago.

Pleistocene Landscape of Siberian Tundra

Mammoths first appeared in Africa early in the Pleistocene Epoch (the last 1.6 million years of the Earth’s history) and later migrated to Europe, Siberia, and across to North America. Proboscideans were very widespread. Their fossil remains can be found on every continent except Australia and South America. Stone spearpoint evidence showing humans hunted mammoths is widespread and may have started with hominids in Africa as early as 1.8 mya. The last of the large mammoths died out between 12,000-10,000 years ago; the Wrangle Island dwarfs survived until at least until 4700 years ago. The extinction of the larger forms has been attributed to both hunting by humans and climatic change.

Mammoth Bone Settlements

In the Dnepr river region of the Ukraine, numerous mammoth bone settlements have been found and recently redated to the epi-Gravettian between 14,000 and 15,000 years ago. However, the oldest known MBS is from the Molodova site, a Neanderthal Mousterian occupation located on the Dniester River of Ukraine, and dated some 30,000 years earlier than most of the known Mammoth Bone Settlements. A mammoth bone dwelling is typically a circular or oval structure with walls made of stacked large mammoth bones, often modified to allow them to be lashed together or implanted into the soil. Within the interior is typically found a central hearth or several scattered hearths. The hut is generally surrounded by numerous large pits, full of mammoth and other animal bones. Ashy concentrations with flint artifacts appear to represent middens; many of the mammoth bone settlements have a preponderance of ivory and bone tools. External hearths, butchering areas and flint workshops are often found in association with the hut: scholars call these combinations Mammoth Bone Settlements (MBS).

Mammoth Hunt - Ukraine

The largest known species, Songhua River Mammoth, reached heights of at least 16 feet at the shoulder. Mammoths would probably normally weigh in the region of 6 to 8 tons, but exceptionally large males may have exceeded 12 tons. However, most species of mammoth were only about as large as a modern Asian Elephant. The woolly mammoth was the last species of the genus. Most populations of the woolly mammoth in North America and Eurasia, as well all the Columbian mammoths in North America, died out around the time of the last glacial retreat 10,000 ya.

Trapping Woolly Mammoth

At the end of the last Ice Age, when the climate was cooler and big game lumbered across grasslands and forests of what is now Eastern Europe, Cro-Magnon paleo-hunters trapped mammoths and other prey in marshy areas and excavated pits covered in camouflage or drove them off cliffs. The big-game bonaza didn't last. Over-hunting and climate change led to the extinction of the megafauna in the Late Pleistocene 10,000 to 11,000 years ago.

Cro Magnon

The Cro-Magnon were the first early modern humans (early Homo sapiens sapiens) of the European Upper Paleolithic in Europe. The earliest known remains of Cro-Magnon-like humans are radiometrically dated to 35,000 years before present. Cro-Magnon (a deprecated term- now replaced with 'Anatomically Modern or Early Modern Humans') evolved in East Africa some 100,000 to 200,000 years ago. An exodus from Africa over the Arabian Peninsula around 60,000 years ago brought modern humans to Eurasia, with one group rapidly settling coastal areas around the Indian Ocean and one group migrating north to steppes of Central Asia. The inland group is the founder of North and East Asians (the 'Mongol' people), Caucasoids and large sections of the Middle East and North African population. Migration from the Black Sea area into Europe started some 45,000 ya, probably along the Danubian corridor. By 20,000 years ago, the whole of Europe was settled.

Cave Art

The earliest known European cave paintings date to Aurignacian, some 32,000 years ago. The purpose of the paleolithic cave paintings is not known. The evidence suggests that they were not merely decorations of living areas, since the caves in which they have been found do not have signs of ongoing habitation. Also, they are often in areas of caves that are not easily accessed. Some theories hold that they may have been a way of communicating with others, while other theories ascribe them a religious or ceremonial purpose.

Cro-Magnon Spiritual Consciousness

Complex mortuary rituals and belief in the transmigration of the soul, of a world beyond the grave, has been a human characteristic for at least 100,000 years. The emergence of spiritual consciousness and its symbolism, is directly linked to the evolution of the temporal and frontal lobes and to the Neanderthal and Cro-Magnon peoples, and then the first cosmologies, 20,000 to 30,000 years ago. These ancient peoples of the Upper and Middle Paleolithic were capable of experiencing love, fear, and mystical awe, and they carefully buried those they loved and lost. They believed in spirits and ghosts which dwelled in a heavenly land of dreams, and interned their dead in sleeping positions and with tools, ornaments and flowers. By 30,000 years ago, and with the expansion of the frontal lobes, they created symbolic rituals to help them understand and gain control over the spiritual realms, and created signs and symbols which could generate feelings of awe regardless of time or culture.

The Cave Bear

Ursus spelaeus was a species of bear which lived in Europe during the Pleistocene and became extinct at the beginning of the Last Glacial Maximum about 27,500 years ago. There undoubtedly were regular encounters with homo sapiens who competed with a large population of the giant bears for cave shelters since caves have been discovered with the remains of thousands of bears. The main difference between the cave bear and the brown bear of today is the size: the weight of a male could be up to 1 ton, with shoulder height about 30% bigger than the brown bear. Collections of bear bones at several widely dispersed sites suggest that Neanderthals may have worshiped cave bears.

Cro Magnon Hunters

In Europe, the first modern humans appear in the archaeological record rather suddenly around 40,000 years ago. The abruptness of the appearance of these Cro-Magnon people could be explained by their migrating into the region from Africa via Southwest Asia. They apparently shared Europe with Neandertals for another 12,000 years. A computer-based analysis of 10 different human DNA sequences suggests interbreeding between people living in Asia, Europe, and Africa for at least 600,000 years although most skeletons of Neandertals and Cro-Magnon people do not show hybrid characteristics. It is also possible that migrations were not only in one direction--people could have migrated into Africa as well. The Genographic Project traced y chromosomes of Toubou of Chad to show that their ancestors had migrated back into northern Africa from populations settled in the middle east some 30 Kya.

Homo sapiens - Treking for 200,000 years

Humans, known taxonomically as Homo sapiens, are the only extant member of the Homo genus of bipedal primates in Hominidae, the great ape family. However, in some cases 'human' is used to refer to any member of the genus Homo. Humans have a highly developed brain, capable of abstract reasoning, language, introspection and problem solving. This mental capability, combined with an erect body carriage that frees the hands for manipulating objects, has allowed humans to make far greater use of tools than any other species. Mitochondrial DNA and fossil evidence indicates that modern humans originated in Africa about 200,000 years ago

Early Caucasoid People

Physical anthropologists generally consider the Cro-Magnons, who emerged during the Upper Paleolithic or Later Stone Age, as the earliest or prototypical representatives of the Caucasoid race. In a study of Cro-Magnon crania researchers have noted that Upper Paleolithic crania are, for the most part, larger and more generalized versions of recent Europeans. Based on their cranial traits the Cro-Magnons were already racially European. Proponents of the multiregional origin of modern humans argue that Caucasoid traits emerged prior to the Cro-Magnons, and are present in the Skhul and Qafzeh hominids as well as in the Neanderthals. More recent analysis of Cro-Magnon fossils suggests they may have had brown skin. The hunter-gatherers of the Palaeolithic also possibly built shelters such as those identified in connection with Acheulean tools at Grotte du Lazaret and Terra Amata near Nice in France. The presence of the shelters is inferred from large rocks at the sites, which may have been used to weigh down the bottoms of tent-like structures or serve as foundations for huts or windbreaks.

Homo sapiens Social Bonding

Homo sapiens, which is considered to be the third link in the chain of evolution, has a greater propensity for bonding and cooperation than any other creature, including its now extinct cousins, Homo erectus and Homo neanderthalenis. What distinguishes H. sapiens from its earlier cousins was its large cranial cavity, which permitted the development and growth of the neocortex - the part of the brain that enabled thought, imagination, speech and language - all facilitators of survival through social bonding and cooperation. It is this capacity for communication, imagination and abstract thought, such as anticipating future events, that many believe gave H. sapiens an evolutionary advantage over its cousins.

Homo floresiensis

Homo floresiensis fossils were discovered in a cave called Liang Bua on the Indonesian island of Flores. This hominid stood only three feet high, earning it the nickname The Hobbit. It lived as recently as 18,000 years ago, which was some 30,000 years after our own species had already been in southeast Asia for 30,000 years or more.

Homo floresiensis

A recent full-body reconstruction of the ‘little lady of Flores’. The discovery of Homo floresiensis in 2003 and of the recentness of its extinction has raised the possibility that numerous descendant species of Homo erectus may have existed in the islands of Southeast Asia and await fossil discovery. Homo erectus soloensis, who lived on Java at least as late as about 50,000 years ago, would be one of them. Some scientists are skeptical of the claim that Homo floresiensis is a descendant of Homo erectus.

Toba Supermassive Eruption

The volcanic eruption that resulted in Lake Toba (100 x 30 km) 74,000 years ago, is known to have been by far the biggest eruption of the last 2 million years. The Toba event specifically covered India, Pakistan, and the Gulf region in a blanket of ash 3–15 feet deep. Toba is also regarded by some as having caused worldwide population extinctions as a result of the 'nuclear winter' that followed. Although a deep east-west division, or 'furrow', is still seen clearly in the genetic record, scholars are conflicted whether the Toba volcano led to severe and wholesale environmental destruction or, as recent research in India suggests, a mosaic of ecological settings was present, and some areas experienced a relatively rapid recovery after the volcanic event.

Climatic and Geologic Shifts

Paleoanthropologists – scientists who study human evolution – have proposed a variety of ideas about how environmental conditions may have stimulated important developments in human origins. Diverse species have emerged over the course of human evolution, and a suite of adaptations have accumulated over time, including upright walking, the capacity to make tools, enlargement of the brain, prolonged maturation, the emergence of complex mental and social behavior, and dependence on technology to alter the surroundings. The period of human evolution has coincided with environmental change, including cooling, drying, and wider climate fluctuations over time. How did environmental change shape the evolution of new adaptations, the origin and extinction of early hominin species, and the emergence of our species, Homo sapiens? (‘Hominin’ refers to any bipedal species closely related to humans – that is, on the human divide of the evolutionary tree since human and chimpanzee ancestors branchedoff from a common ancestor sometime between 6 and 8 million years ago.)

Archaic Homo sapiens Culture

The Upper Paleolithic (or Upper Palaeolithic, Late Stone Age) is the third and last subdivision of the Paleolithic or Old Stone Age as it is understood in Europe, Africa and Asia. Very broadly, it dates to between 50,000 and 10,000 years ago, roughly coinciding with the appearance of behavioral modernity and before the advent of agriculture. Upper Paleolithic humans (about 30,000 years ago) are about 20 to 30% more robust than the modern condition in Europe and Asia. These are considered modern humans, although they are sometimes termed 'primitive'.

Homo antecessor

La familía' Portrait of an extended family of early hominids whose fossil remains were discovered in a 'pit of bones' site in a cave in Atapuerca, Spain. Anatomical evidence has been uncovered that shows they fabricated tools more than one million years ago so may be the earliest West European hominid.

Homo antecessor

Homo antecessor is an extinct human species (or subspecies) dating from 1.2 million to 800,000 years ago, that was discovered in Atapuerca, Spain. Antecessor is one of the earliest known human varieties in Europe. Various archaeologists and anthropologists have debated how H. antecessor related to other Homo species in Europe with suggestions that it was an evolutionary link between Homo ergaster and Homo heidelbergensis, although Richard Klein believed that it was instead a separate species that evolved from H. ergaster or that H. antecessor is the same species of H.heidelbergensis, who inhabited Europe from 600,000 to 250,000 years ago in the Pleistocene.

Homo antecessor Cannibal Feast

At the Atapuerca site were numerous examples of cuts where the flesh had been fleshed from the bones of H. antecessor remains, suggesting ritualistic preparation or possibly cannibalism may have been practiced.

Meeting

As of 2010, genetic evidence suggests interbreeding took place with Homo sapiens sapiens (anatomically modern humans) between roughly 80,000 to 50,000 years ago in the Middle East, resulting in indigenous sub-Saharan Africans having no Neanderthal DNA, and Caucasians and Asians having between 1% and 4% Neanderthal DNA. However, specimens with combined Human and Neanderthal traits have also been found in Spain as recently as 40,000 BC suggesting long term and widespread intermingling of 'anachronistic races' throughout history. The evidence is controversial since Neanderthals lived in Europe and western Asia from 230,000 to 29,000 years ago, petering out soon after the arrival of modern humans from Africa.

Modern-Archaic Human Admixture

There have been several instances of archaic human admixture with modern humans through interbreeding of modern humans with Neanderthals, Denisovans, and/or possibly other archaic humans over the course of human history. Neanderthal-derived DNA accounts for an estimated 1–4% of the Eurasian genome, but it is significantly absent or uncommon in the genome of most Sub-Saharan African people. In Oceanian and Southeast Asian populations, there's a relative increase of Denisovan-derived DNA. An estimated 4–6% of the Melanesian genome is derived from Denisovans

Denisova hominin Enigma

A new type of hominid - Homo denisova - discovered via a single pinky finger, toe bone and tooth from 40 K year old Siberian fossils points to unknown migration out of Africa. The new-human discovery implies that there was a wave of human migration out of Africa around a million years ago that was completely unknown to science. The Denisovans likely roamed eastern Asia for thousands of years, probably interbreeding occasionally with both Neanderthals and the earliest Homo sapiens migrants. Melanesians, together with Papuan people and Australian Aborigines, are the only known modern humans whose prehistoric ancestors interbred with the Denisova hominin, sharing 4%–6% of their genome with this ancient human species.

The Jawara Andamanese People - live in the Andaman Islands, a district of India located in the southeastern part of the Bay of Bengal. They are one of several aboriginal populations descended from mutiple migrations which, about 60,000 years ago, brought modern humans out of Africa to localities along the coastlines of the Indian Ocean as far as Australia. They still lead a hunter-gatherer life style in their Jarawa Reserve jungle but are threatened by both tourist exploitation and abuse by native outsiders.

Melanesia Rafting

Some researchers claim there is sufficient evidence that suggests that at least two different populations colonised the Americas. Paleolithic austro-melanesians - descendants of interbreeding between Denisova hominin and archaic Homo sapiens - with their insatible wunderlust and oceanic maritime skills may have continued their treking and rafting even via extra-Beringial trans-pacific migration to become the earliest people to populate the Americas. Relatives of present-day East Asians were not in Southeast Asia when the Denisova gene flow occurred. The ancestors of Melanesians met the Denisovans in Southeast Asia and interbred, and the ancestors of Melanesians then moved on to Papua New Guinea.

H. sapiens Migration Out of Africa

At one mile per year, early H. sapiens may have left Africa and migrated along the shoreline of the Indian Ocean and traveled seven thousand miles to reach Far East Asia more than 60 Kya.

Ventures Out of Africa

Leaders of a band of Homo sapiens sapiens are pictured approaching the southern highlands of the Asir Mountains in the Arabian peninsula, 50 Kya. The Djibouti-Aden isthmus formed several times during intermittent glacial event, allowing both early and late H. sapiens to trek or raft into Arabia. During many times in the past, the region was well-watered, with rivers and lakes. Behaviorally modern humans appear to have evolved in Africa about 150,000 years ago and began a sustained migration out of Africa around 50,000 years ago. Pictured are members of a group that may have been as few as 150 individuals that could be ancestors of all modern humans. It is proposed they ranged first to Australia- then to Central Asia.

Early Homo sapiens idaltu

A reconstruction of a large-brained Homo sapiens skull reveals the imposing face of the Herto man. The remains along with others at the site near the village of Herto on the Bouri Peninsula in Ethiopia date to between 160,000 and 154,000 years ago. Large cleavers (7.5 inches long) and other flaked stone tools were used to butcher hippo. Crude stone tools first appear 2.6 million years ago with our australopithecine ancestors. H. sapiens remains in Morocco have been dated to 160 Kya. The earliest H. sapiens specimens found outside of Africa come from a 90 Kya site in Israel but this early colony seemed not to have endured perhaps due to competition from neanderthals.

Neanderthal Family

Proto-Neanderthal traits are occasionally grouped to another phenetic 'species', Homo heidelbergensis, or a migrant form, Homo rhodesiensis. By 130,000 years ago, complete Neanderthal characteristics had appeared. These characteristics then disappeared in Asia by 50,000 years ago and in Europe by about 30,000 years ago, with no further individuals having enough Neanderthal morphological traits to be considered as part of Homo neanderthalensis.

Homo neanderthalensis

The Neanderthal (also spelled Neandertal) is an extinct member of the Homo genus that is known from Pleistocene (the epoch from 2.588 million to 12,000 years BP covering the world's recent period of repeated glaciations). Neanderthals- found in Europe and parts of western and central Asia- are either classified as a subspecies (or race) of humans (Homo sapiens neanderthalensis) or as a separate species (Homo neanderthalensis). Over the past fifty years, reconstructions of Neanderthal have portrayed a wide range of character between primitive and modern features.

Neanderthal Diorama

Chicago Field Museum 1980 - Figure in a diorama of Neanderthal Family - father, mother, grandmother and children. Upper rock-shelter at Le Moustier, France. By 1994, the Hall of the Stone Age of the Old World exhibit had been dismantled because most were considered to be scientifically inaccurate including the Neanderthal Family diorama. Subsequent reconstructions of neanderthal tend to have less primitive facial features with closer resemblance to early Homo sapiens.

Neanderthal-Sapiens Interbreeding

Science has long since killed off the notion that Homo neanderthalensis was a hairy dimwit who stumbled around Ice Age Eurasia on bent knees, eventually to be replaced by smart, elegant, upright Cro-Magnon, the true ancestor of modern Europeans. Scientists have found that 2.5 percent of the genome of an average human living outside Africa today is made up of Neanderthal DNA. The average modern African has none. DNA analysis suggests that modern humans and Neanderthaland mixed genes most likely 47,000 to 65,000 years ago probably in the Middle East, where the early modern humans migrating out of Africa would have encountered Neanderthals already living there. Interbreeding] could have been a really powerful mechanism for humans to adapt as they moved into Eurasia including a family of genes that helped their immune system fight off viruses.

Interglacial Neanderthal

Researchers say genetic sampling suggests that early Homo sapiens interbred with neanderthal about 60,000 years ago in the eastern Mediterranean and, more recently, about 45,000 years ago in eastern Asia. Those two events happened after the first H. sapiens had migrated out of Africa so H. sapiens confined in Africa have no trace of neanderthal inheritance.

Homo neanderthal female

Female Neanderthal brains were about 200 cm smaller than those of males. This sexual dimorphism should not be a surprise since female bodies were smaller. Modern human female brains are about 10% smaller than those of males for the same reason. It would be a mistake to assume that a minor difference in overall brain size is directly correlated with intelligence among archaic or modern humans.

Neanderthal - Ice Age

Neanderthal Toolmaking

By 100,000 years ago or somewhat earlier, Neandertal and some other late archaic humans achieved a major leap forward in tool making with the development of the Mousterian tool tradition in France. This new technology was revolutionary enough to warrant being considered a distinct Paleolithic phase--the Middle Paleolithic. Mousterian-like tool industries were employed at that time also by early modern Homo sapiens in some areas of Africa and Southwest Asia.

Homo neanderthalensis

Female hunters may have doomed Neanderthals by putting the reproductive core in harm's way and may have contributed to the Neanderthals' extinction, says a recent study. It uses archaeological evidence to argue that Neanderthal females hunted—and were stomped, gored, and worse—alongside males. Pitting the reproductive core of a population that never topped 10,000 against giant beasts could bring doom to a hard-pressed species.

Homo neanderthal Child

The Gibraltar 2 Neanderthal child specimen is represented by 5 cranial fragments recovered by Dorothy Garrod at the Devil’s Tower site in Gibraltar (Garrod et al., 1928).

Homo neanderthal

As of 2010, genetic evidence suggests interbreeding may have taken place with Homo sapiens sapiens (anatomically modern humans) between roughly 80,000 to 50,000 years ago in the Middle East, resulting in indigenous sub-Saharan Africans having no Neanderthal DNA, and Caucasians and Asians having between 1% and 4% Neanderthal DNA. However, specimens with combined Human and Neanderthal traits have also been found in Spain as recently as 40,000 BC suggesting long term and widespread intermingling of 'anachronistic races' throughout history.

Homo heidelbergensis

The best evidence found for these hominin date around 500,000 years ago. H. heidelbergensis stone tool technology was very close to that of the Acheulean tools used by Homo erectus and is likely to be descended from the morphologically very similar Homo ergaster from Africa. But because H. heidelbergensis had a larger brain-case overlapping the average of modern humans — and had more advanced tools and behavior, it has been given a separate species classification. The species was 6 ft tall on average, and more muscular than modern humans.

Homo rhodesiensis

(Rhodesian man) is a possible hominin species described from a fossil skull. Other morphologically-comparable remains have been found from the same, or earlier, time period in other widespread African localities. These remains were dated between 300,000 and 125,000 years old. Most current experts believe Rhodesian Man to be within the group of Homo heidelbergensis though other designations such as Homo sapiens arcaicus and Homo sapiens rhodesiensis have also been proposed. It is possible that Homo rhodesiensis was the ancestor of Homo sapiens idaltu (Herto Man), which would be itself at the origin of Homo sapiens sapiens although no direct linkage of the species can so far be determined.

Homo heidelbergensis

It is difficult to speak of our ancestors in terms of specific species during this long period of accelerated change from 800,000 to 100,000 years ago. The more biologically progressive post-800,000 B.P. populations in Europe and Africa are commonly classified as a distinct species--Homo heidelbergensis. By 300,000 years ago, some of these populations had begun the evolutionary transition that would end up with Neandertals and other archaic humans (also called archaic Homo sapiens and pre-modern humans). By 100,000 years ago, some populations had evolved into modern humans. Others remained largely unchanged until about 28,000 years ago, when they became extinct. These were the Neandertals.

Homo heidelbergensis

A Family Portrait

Homo heidelbergensis

Position of fosslized skeleton of H. heidelbergensis at Atapuerca found in the Sima de los Huesos site in Spain.

Scavenging Elephant Carcass

Early humans lived in the Olorgesailie region, in what is now the southern Kenya, between 1.2 million and 490,000 years ago. The elephant butchery site at Olorgesailie, in the 990,000-year-old layer, illustrates the kind of opportunities that existed for hominins in the Olorgesailie basin. More than 2300 stone artifacts were found surrounding the bones of an extinct elephant, Elephas recki. Many of these artifacts were sharp flakes that could have been used to extract meat from the carcass.

Homo erectus pekinensis

Peking Man, also called Sinanthropus pekinensis (currently Homo erectus pekinensis), is an example of Homo erectus. A group of fossil specimens was discovered in 1923 near Beijing, China. More recently, the finds have been dated from roughly 500,000 years ago, although a new dating suggests they may be as much as 680,000-780,000 years old. Some Chinese paleoanthropologists have asserted in the past that the modern Chinese (and possibly other ethnic groups) are descendants of Peking Man. However, a recent study undertaken by Chinese geneticist Jin Li showed that the genetic diversity of modern Chinese people is well within that of the whole world population, which suggests there was no inter-breeding between modern human immigrants to East Asia and Homo erectus, such as Peking Man, and that the Chinese are descended from Africa, like all other modern humans.

Pre Neolithic Spear Making

The earliest known modified stone tools belong to the Oldowan Industry and date to about 2.6 to 2.0 mya. Earlier hominin-fashioned tools likely were found-stone objects hafted on wood shafts and before lithic technology evolved, the tips of wood spears were probably fire-hardened. Pre-neolithic weaponmakers may have refined fire-hardening wooden spear point technology by first rubbing the end against a smooth rock surface to fashion a point then thrusting it into the coals. This put a light coating of carbon on the surface, which was then polished with a special stone, which ground fine particles of stone into the pitch which had been brought to the surface of the wood by the fire. It is then polished with a special stone that grinds fine particles of stone into the pitch which is brought to the surface of the wood by the fire. Subsequent firings and polishings of the wooden tip of the spear eventually forms a hardened glaze consisting of pitch, wood particles and carbon on the tip which can be even harder than a copper tip. This kind of technology may have begun by primitive hominin - possibly Australapithecus sediba more than 2.6 million years ago — before flaked stone points.

Pleistocene Landscape of Siberian Tundra

Mammoths first appeared in Africa early in the Pleistocene Epoch (the last 1.6 million years of the Earth’s history) and later migrated to Europe, Siberia, and across to North America. Proboscideans were very widespread. Their fossil remains can be found on every continent except Australia and South America. Stone spearpoint evidence showing humans hunted mammoths is widespread and may have started with hominids in Africa as early as 1.8 mya. The last of the large mammoths died out between 12,000-10,000 years ago; the Wrangle Island dwarfs survived until at least until 4700 years ago. The extinction of the larger forms has been attributed to both hunting by humans and climatic change.

Homo heidelbergensis

Most experts now agree that H. heidelbergensis is the direct ancestor of H. sapiens (with some uncertainty about such specimens as H. antecessor, now largely considered H. heidelbergensis) and H. neanderthalensis. Because of the radiation of H. heidelbergensis out of Africa and into Europe, the two populations were mostly isolated during the last of the prolonged Quaternary glacial periods. Neanderthals diverged from H. heidelbergensis probably some 300,000 years ago in Europe, H. sapiens probably diverged between 200,000 and 100,000 years ago in Africa.

Homo erectus

Homo erectus is an extinct species of hominid that originated in Africa—and spread as far as China and Java—from the end of the Pliocene epoch to the later Pleistocene, about 1.8 to 1.3 million years ago. There is still disagreement on the subject of the classification, ancestry, and progeny of H. erectus, with two major alternative hypotheses: erectus may be another name for Homo ergaster, and therefore the direct ancestor of later hominids such as Homo heidelbergensis, Homo neanderthalensis, and Homo sapiens; or it may be an Asian species distinct from African ergaster.

Nariokotome Boy

Nariokotome Boy (more commonly known as Turkana Boy) is the epithet of a fossil discovered at Nariokotome near Lake Turkana in Kenya. It proved to be a nearly complete skeleton of a hominid (Homo erectus or H. ergaster) male, dated to the early Pleistocene 1.5 Mya. He was roughly 8 years old. His jaw shows that he had a diseased gum where a deciduous molar – one of his baby teeth – had been shed. An infection seems to have set in and he probably died of septicaemia (blood poisoning).

Currently, there are two unresolved hypotheses concerning Homo erectus: (1) Specimens assigned to Homo ergaster should be assigned to erectus, which would then be the direct ancestor of later hominids such as Homo heidelbergensis, Homo neanderthalensis, and Homo sapiens; or, alternatively, (2) erectus may be an Asian form distinct from African ergaster. Whichever of these views is correct, Homo erectus is the earliest hominid known outside of Africa, and was perhaps also the first to use fire.

Homo ergaster

The discovery of Turkana boy (H. ergaster) in 1984 gave evidence that, despite its Homo-sapiens-like anatomy, it may not have been capable of producing sounds comparable to modern human speech. Ergaster at least may have communicated with a pre-language lacking the fully developed structure of modern human language, but more developed than the basic communication used by chimpanzees. Such inference has been challenged by the discovery of H. ergaster/erectus vertebrae some 150,000 years older than the Turkana Boy in Dmanisi, Georgia, that reflect vocal capabilities within the range of H. sapiens. Both brain-size and the presence of the Broca's area also support the use of articulate language.

Homo ergaster

Several different species of the genus primateus Homo lived in Africa around two million years ago. Of these species, Homo ergaster is the most plausible ancestor of modern humans—or we could be descended from a species that has yet to be discovered. Homo ergaster: This species had a body essentially like that of modern humans: long legs, short arms and in some specimens a moderately large brain.

Paranthropus

Paranthropus is a genus of extinct hominins also known as robust australopithecines who were bipedal hominids that probably descended from the gracile australopithecine hominids 2.7 million years ago. Since the discovery of the 'type specimen' of this species by Mary Leakey in 1959, more than 300 Paranthopus fossils have been uncovered and three species are included in this group. A cast of a Paranthropus boisei skull that dates to about 1.8 million years old is shown. This is the 'type specimen' of this species. The contrasts in reconstructions of Paranthropus are a prime example of the range of interpretations of fossil evidence by fully qualified paleo artists.

Parenthropus boisei

(previously Autralopithecus boisei) P. boisei is usually thought to descend from earlier P. aethiopicus (who inhabited the same geographic area just a few hundred thousand years before) and lived alongside several other species of early humans such as Homo habilis, during its 1.1 million year existence. However, H. habilis, possibly because of its early tool innovation and a less specialized diet, became the precursor of an entire line of new species, whereas Paranthropus boisei and its robust relatives disappeared from the fossil record. Homo habilis may also have coexisted with Homo erectus in Africa for a period of 500,000 years. H P. boisei belongs to just one of the many side branches of human evolution, which most scientists agree includes all Paranthropus species and did not lead to H.sapiens.

Paranthropus boisei

P. boisei was an early hominin and described as the largest of the Paranthropus species. It lived from about 2.6 until about 1.2 million years ago during the Pliocene and Pleistocene epochs in Eastern Africa. The brain volume is quite small, not much larger in comparison to Australopithecus afarensis and Australopithecus africanus. It had a skull highly specialized for heavy chewing and several traits seen in modern day gorillas.

Control of Fire

The control of fire by early humans was a turning point in the cultural aspect of human evolution that initially provided protection from cold, predators and insects then applied to tool processing and cooking food with significant nutritional effect on the evolution to larger brains. Making fire also allowed the expansion of human activity into the dark and colder hours of the night imbuing aspects of our distinctly human consciousness. Evidence of widespread control of fire dates to approximately 125,000 years ago and earlier. Evidence for the controlled use of fire by Homo erectus beginning some 400,000 years ago has wide scholarly support, with claims regarding earlier control of fire ranging from 0.2 to 1.7 million years ago finding increasing scientific support. Based on the feeding time comparison between human and nonhuman primates (4.7% versus predicted 48% of daily activity), researchers have inferred that this is due to an evolutionary consequence of control of fire and food cooking by members of the Homo genus as early as 1.9 million years ago.

Homo ergaster

Homo ergaster first appeared on the scene about two million years ago. They were tall and slender, with long legs and larger brains than most of their predecessors so may be very early precursors of modern humans. A nearly complete 1.6-million-year-old skeleton, found near Lake Turkana, Kenya, belonged to an eight-year-old boy. Nicknamed 'Turkana Boy', Turkana Boy and his kind were tall and lanky—and completely at home striding out on the open savanna.

Homo ergaster

Homo ergaster is one of the more problematic of somewhat accepted species designations currently tossed around in anthropological literature. Each individual researcher that sees ergaster as a valid taxon sees different specimens as belonging or not belonging to the taxon. Many researchers deny any validity to the species at all. On the whole though, most researchers see too little difference between ergaster and erectus to form the basis of a species of the former, separated from the latter. As a general rule of thumb, one can consider most attributed ergaster specimens to be early erectus geographically confined to Africa (however, this is not a hard and fast rule). Even if ergaster specimens are considered as a different taxon than erectus, the erectus material is still closer to modern humans cladistically. In short at this time, ergaster basically means early H. erectus from Africa.

Dmanisi Hominids

The skull and jawbone of a small, lightly-built individual, discovered at an archeological site in Dmanisi, Georgia, may call into question the prevailing idea that larger brain size was behind the migration of human ancestors out of Africa. The scientists found a petite new individual, with a small brain, thin brow ridge, short nose, and huge canine teeth. The specimens compare in size and morphology with Homo ergaster from Koobi Fora, Kenya. All three specimens are approximately 1.75 million years old. The little 'people' have caused a lively debate amongst palaeoanthropologists. Many experts believe it was Homo erectus who first ventured out of Africa and spread around Asia but Dmanisi hominids were not typical of the tall-standing, big brained Homo erectus. This has led some to believe they may have been Homo habilis or H. georgicus but these relatively ape-like species were not thought to have lived outside Africa.

Daminisi Hominin Reconstruction

Professor David Lordkipanidze, general director of the Georgia National Museum raised the prospect that Homo erectus may have evolved in Eurasia from the more primitive-looking Dmanisi population and then migrated back to Africa to eventually give rise to our own species, Homo sapiens – modern man. Although their brains were tiny compared to ours (600 cc compared to 1,000 cc) they were sophisticated tool makers with high social and cognitive skills. The only human fossil to predate the Dmanisi specimens are of an archaic species Homo habilis, or 'handy man', found only in Africa, which used simple stone tools and lived between about 2.5 million and 1.6 million years ago.

Homo georgicus

H. georgicus is a species of Homo that was suggested in 2002 to describe fossil skulls and jaws found in Dmanisi, Georgia in 1999 and 2001, which seem intermediate between Homo habilis and H. erectus. A partial skeleton was discovered in 2001. The fossils are about 1.8 million years old. Size differences in the fossil evidence led scientists to name Homo georgicus a new species, which would be the descendant of Homo habilis and ancestor of Asian Homo erectus. In Georgia the specimens with a brain half brain the size compared to anatomically modern humans were considered the smallest until the discovery of Homo floresiensis from the island of Flores in 2003.

Gigantopithecus blacki

G. blacki is an extinct species of ape that existed for about a million years, going extinct about 100,000 years ago after having been contemporary with modern humans for tens of thousands of years, and co-existing with H. erectus. Based on the fossil evidence, it is believed that adult male G. blacki stood about 9.8 ft tall and weighed as much as 1,200 lbs, making the species two to three times heavier than modern gorillas and nearly five times heavier than the orangutan, its closest living relative.

Homo rudolfensis

Homo rudolfensis Homo rudolfensis is a fossil human species discovered by a team led by anthropologist Richard Leakey and zoologist Meave Leakey in 1972 in Kenya. The scientific name Homo rudolfensis was proposed for the specimen skull that has an estimated age of 1.9 million years. Originally assigned initially to Homo habilis, the skull was at first incorrectly dated at nearly three million years old. The differences in this skull, when compared to others of the Homo habilis species, are too pronounced, leading to the presumption of a Homo rudolfensis species, contemporary with Homo habilis. It is not certain if H. rudolfensis was ancestral to the later species in Homo, or if H. habilis was, or if some third species yet to be discovered was.

Homo rudolfensis

A new discovery of a fossil cranium and two jawbones—both 2 million years old—lead researchers to confirm that Homo rudolfensis is a distinct species. The first Homo rudolfensis skull was found in northern Kenya in 1972. The newly discovered fossil face is flat, as in the original skull. The partial jawbones look similar to the skull found in 1972 but enlarge the known variation in the skull and teeth of Homo rudolfensis. Along with fossils of Homo habilis and Homo erectus, these new specimens support the existence of multiple species of Homo in eastern Africa between about 2.0 and 1.7 million years ago.

Homo habilis at Lake Turkana

Homo habilis ('handy man') is a species of the genus Homo, which lived from approximately 2.3 to 1.4 million years ago at the beginning of the Pleistocene period. Homo habilis (or possibly H. rudolfensis) is the earliest known species of the genus Homo. In its appearance and morphology, H. habilis is thus the least similar to modern humans of all species in the genus (except possibly H. rudolfensis). H. habilis was short and had disproportionately long arms compared to modern humans; however, it had a less protruding face than the australopithecines from which it is thought to have descended. H. habilis had a cranial capacity slightly less than half of the size of modern humans. Despite the ape-like morphology of the bodies, H. habilis remains are often accompanied by primitive stone tools.

Homo habilis

Homo habilis has often been thought to be the ancestor of the more gracile and sophisticated Homo ergaster, which in turn gave rise to the more human-appearing species, Homo erectus. Debates continue over whether H. habilis is a direct human ancestor, and whether all of the known fossils are properly attributed to the species. However, in 2007, new findings suggest that the two species coexisted and may be separate lineages from a common ancestor instead of H. erectus being descended from H. habilis.

Homo habilis

H. habilis fossils were subjected to intense study by the multidisciplinary team of Louis Leakey, John Napier, and Phillip Tobias. They placed the material which fell outside the known range of A. africanus. Also, the large brain size and shape of the hand suggested a closer affinity with Homo. In January 1964, the team announced the new species Homo habilis. Leakey believed that habilis was a direct human ancestor, with erectus out of the picture. There are now at least two species of early Homo (whether habilis and rudolfensis or an undescribed species) living prior to 2.0 myr. In addition, H. erectus (which is almost universally accepted as a direct human ancestor) continues to be pushed further back into the paleontological record, making it possible that it is the first Homo ancestor of modern humans.

Australopithecus sediba

In 2010, the richest collection of fossil skeletons ever found were discovered at a site called Malapa in South Africa and could represent the long-sought ancestor of the genus Homo. A. sediba remains date to 1.98 mya and may be an intermediate species between the primitive Australopithecus afarensis (Lucy - a millon years older) and early hominins. Many anatomical features hark back to earlier australopiths, such as A. africanus, from between two and three million years ago. On the human side of the ledger, long legs, a modern ankle and surprisingly humanlike pelvis built for a fully bipedal stride; smaller teeth and chewing muscles; a projecting nose and some other features of the face; and a remarkable, precision-grip hand - traits enough for the team to propose it as the australopith species most likely to have given rise to Homo.

Australopithecus garhi

National Geograhic magazine places Au. garhi in direct ancestral lineage to H. sapiens- midway between, Au. afarensis and H. erectus. It's teeth are described as having some Homo features but otherwise as a clever, two-legged primate eking out a furtive existence among larger, faster predators and avoiding their jaws long enough to pass on its ripening intelligence on to the next generation.

Australopithecus garhi

Australopithecus garhi is a gracile australopithecine species whose fossils were discovered in 1996 by a research team led by Ethiopian paleontologist Berhane Asfaw and Tim White, an American paleontologist. Few primitive shaped stone tool artifacts closely resembling Olduwan technology were discovered with the A. garhi fossils, dating back roughly 2.5 and 2.6 million years old. The hominin remains are believed to be a human ancestor species and the final missing link between the Australopithecus genus and the human genus, Homo. A. garhi may be the first hominid whose diet included other animals.

Australopithecus garhi

An alternative reconstruction showing a more primitive ape-like specimen. On open ground our Australopithecus ancestors were more likely to be prey for lions and hyenas than competitors for their kills. Then the game changed. Crude stone tools first appear 2.6 million years ago. Some 100,000 years later, hominids on the Bouri Peninsula in Ethiopia used stone tools to scavenge meat and marrow from large mammal carcasses. Such high-energy foods would be the perfect diet for evolving the metabolically expensive bigger brains characteristic of later Homo.

Paranthropus robustus

P. robustus (aka Australopithecus robustus) known from a 2 M year-old fossil find in South Africa, had a head shaped a bit like a gorilla's with a more massive built jaw and teeth in comparison to hominins within the Homo lineage. Males may have stood only 4 feet tall and weighed 120 lb while females stood just under 3 feet 2 inches tall and weighed only 90 lb, indicating a pronounced sexual dimorphism. P. robustus had large sagittal crests, jaws, jaw muscles, and post-canine teeth that were adapted to serve in the dry environment that they lived in. The average brain size of P. robustus measured to only 410 and 530 cc, about as large as a chimpanzee's.

Homo rudolfensis

Homo rudolfensis: from Koobi Fora in the Lake Turkana basin, Kenya. It has one really critical feature: a braincase size of 775 cubic centimeters, which is considerably above the upper end of H. habilis braincase size. At least one other braincase from the same region also shows such a large cranial capacity. Originally considered to be H. habilis, the ways in which H. rudolfensis differs is in its larger braincase, longer face, and larger molar and premolar teeth. Due to the last two features, though, some scientists still wonder whether this 'species' might better be considered an Australopithecus, although one with a large brain!

Paranthropus aethiopicus

P. aethiopicus is an extinct species of hominid discovered in 1985 in West Turkana, Kenya. Known as the 'Black Skull' due to the dark coloration of the bone, caused by high levels of manganese), it is one of the earliest examples of robust Pliocene hominids. The skull is dated to 2.5 million years ago, older than the later forms of robust australopithecines. The features are quite primitive and share many traits with Australopithecus afarensis; thus P. aethiopicus is likely to be a direct descendant but along with Paranthropus boisei and Paranthropus robustus and some other Austraopithicines is on an evolutionary branch of the hominid tree, distinctly diverging from the Homo (human) lineage.

Paranthropus (or Australopithecus) robustus

Paranthropus robustus (considered for a time by the scientific community as Australopithecus robustus) is generally dated to have lived between 2.0 and 1.2 million years ago.

Australopithecus africanus

Perhaps one of the last members of his species to lose the struggle against extinction.

Kenyanthropus platyops

Two isolated fossils (a fragmentary upper jaw and badly abraded skull) are all that can be clearly assigned to this species. The fossils were found in Kenya and are believed to have originated three million, three hundred thousand years ago. Kenyanthropus may not even represent a valid taxon, as the specimens are so distorted by matrix-filled cracks that meaningful morphological characteristics are next to impossible to assess with confidence. It may simply be a specimen of Australopithecus afarensis, which is known from the same time period and geographic area, or its own species within Australopithicus, A. platyops.

Pliocene Pacific Marine Life

Marine life off southern California 3.5 million years ago.

Australopithecus africanus

Australopithecus africanus

A. africanus was an early hominid, an australopithecine, who lived between 2–3 million years ago in the Pliocene. In common with the older Australopithecus afarensis, A. africanus was slenderly built, or gracile, and was thought to have been a direct ancestor of modern humans. Fossil remains indicate that A. africanus was significantly more like modern humans than A. afarensis, with a more human-like cranium permitting a larger brain and more humanoid facial features.

Australopithecus afarensis ('Lucy')

A re-creation of the A. afarensis known as Lucy. Dated at 3.2 million years ago, the set of fossilized pelvic and leg bones found in the badlands of Hadar, Ethiopia indicated that she had walked upright. The species is believed to be the common ancestor of all later human species, including modern humans.

Anancus arvernensis

The order Proboscidea originated in Africa but by the late Miocene had spread over Eurasia. Gomphothere mastodon were endemic to Europe, Africa and Asia during the Pliocene. An A. arvernensis fossil tusk found in late Pliocene sediments (3.4 mya) Northern Pakistan had a length of 8 ft 11 inch so mature specimens could probably reach ten feet or more. It is almost certain that these mastodon and Australopithecus afarensis would have habituated to one another.

Australopithecus afarensis

One of the earliest of modern man's ancestors, Australopithecus afarensis lived between 4 million and 3.2 million years ago in eastern Africa. The teeth and jaws of two dozen hominids where uncovered at Laetoli in Tanzania along with a now famous set of footprints where two early hominids once walked along the shore of an ancient lake around 3.6 million years ago. More individuals were also found at Hadar in Ethiopia and another at Lake Turkana in Kenya. Among those discovered at Hadar was Lucy, a nearly complete skeleton of an Australopithecus afarensis. Weighing about 60 pounds and standing about 3 and 1/2 feet high, Lucy lived about 2.9 million years ago when the eastern region of Africa was semiarid savanna with rainy and dry seasons.

Australopithecus afarensis

Australopithecus afarensis is an extinct hominin which lived between 3.7 and 2.9 million years ago. A. afarensis was slenderly built, like the younger Australopithecus africanus. It is thought that A. afarensis was ancestral to both the genus Australopithecus and the genus Homo, which includes the modern human species, Homo sapiens.

Lucy- Houston Museum

A full-sized model of Dinqnesh (Lucy), the 3.2 million-year-old member of the Australopithecus afarensis, is displayed at the Houston Museum of Natural Science in Houston, Texas.

Australopithecus afarensis

A portrayal of a scene reminiscent of the Laetoli footprints where a pair of A. afarensis left fossil impressions as they walked over a volcanic ashbed. Here the scene is 50K years earlier before the Pliocene forests of the Rift Valley were transformed by cooler, more arid climate into vast grasslands. An A. afarensis couple leave their fleeting footprints in the mud shore of an upland lake. In background: Anacus arvernensis, a Gomphothere mastodon.

Ardipithecus ramidus

Although having incipient bipedality, Ardi lived in a woodland rather than a savannas environment 4.4 million years ago. Even older hominid fossils from the Afar region include Ardipithicus kadabba extending back 5.8 my and likely a chronospecies of Au. ramidus bearing the same relationship to it that Au. anamensis bears to Au. afarensis. Included in this continuum are even older remains tentatively named Orrorin tugenensis (6 my) and Sahelanthopus tchadensis dated close to 7 million years. Between 23 and 5 million years ago a tremendous diversity of ape species evolved throughout most of Africa and Eurasia in the Miocene epoch.

Australopithecus afarensis (Male)

A reconstruction of an A. afarensis male exhibits what experts believe were the apelike features of our ancient ancestors. With a protruding jaw, strong chewing muscles, expansive cheekbones, and a heavy brow, such a skull is thought to have held a brain about one-third the size of a modern human's.

Australopithecus afarensis

Reconstruction of A. afarensis child named 'Salem' (also called Dikika Baby after community in Ethiopia near fossil site) even older than lucy. (National Museum) Lucy was also found in the Awash region. which is famed for its early human fossils. Many anthropologists think A. afarensis was ancestral to the genus Homo, though its exact position in the human family tree remains a matter for debate.

Homo afarensis Group

Signaling with waves and calls, an afarensis group warily moves on after foraging for food. Pollen evidence proves that these hominids lived in forests of juniper and olive trees. Their hips, knees, and ankles enabled a humanlike walk, But long, powerful forearms, curved fingers and toes, and upward tilting shoulders all indicate that afarensis also climbed trees, probably to search for fruits and nuts, possibly to escape predators or to sleep. Thickly muscled, males appear to have averaged five feet and a hundred pounds - at least a foot taller an two-thirds heavier than females.

A. afarensis

An alternative reconstruction of Lucy. Considering the dramatic differences in H. sapiens anatomies and facial features we are all familiar with, it should be expected that reconstructions that are often based on fossil evidence less than a complete jawbone, will present a variety of interpretations.

Australopithecus afarensis

Australopithecus anamensis

A. anamensis is the earliest Austrolopithecine- dated to about 4.2 million years ago and evolved some 200 Ky after Ardi became extinct. He lived perhaps 200 Ky before Lucy had evolved but lived contemporaneously with her for some 200 Ky before his extinction.

Australopithecus anamensis

The fossil remains were initially recovered from a site on the west side of Lake Turkana in Kenya, a site called Kanapoi. For years the specimen's species was debated by those who saw it as Australopithecus, due to its age of approximately 4 Myr, and those who saw it as Homo. After 30 years, the fossil material was given the name Australopithecus anamensis by Meave Leakey et al, because of several important differences with A. afarensis that seem to distinguish it as a separate species. It seems fairly reliable to distinguish the Kanapoi material from A. ramidus, however, it is highly questionable that this material is a separate species from A. afarensis. This will undoubtedly be debated until more specimens are obtained and a clearer comparison between samples can be made. In any case, the similar but more primitive anatomy of anamensis relative to afarensis make it a good candidate for a precursor to afarensis.

Ardipithecus ramidus

In 2009, paleontologists formally announced the discovery of the relatively complete A. ramidus fossil skeleton first unearthed in 1994. The fossil is the remains of a small-brained 110 lb female, nicknamed 'Ardi'. It was discovered in Ethiopia's harsh Afar desert at a site called Aramis in the Middle Awash region. Radiometric dating suggest that Ardi lived about 4.4 million years ago. The Ugalla Primate Project researches chimpanzee adaptation to arid, open habitats as a model for understanding early hominid adaptation. Both chimpanzees and Ardipithecus may have first evolved in an ecosystem resembling the lush rainforest of Udzungwa mountains in present day central Tanzania. Fossil remains of a continuum of hominid species including Ardipithecus kadabba dating between 5.2 and 5.8 mya are found in the same locality as Ardi and Lucy. adapting to increasingly arid conditions.

Ardipithecus ramidus ('Ardi')

Probable life appearance in anterior view

Ardipithecus ramidus and kadabba

Substantial fossil specimens for A. ramidus have been found in Ethiopia's Afar Region that are dated to 4.4 million years ago. In 2009, paleontologists formally classified the remains of a small-brained 110 lb female, nicknamed 'Ardi', first unearthed in 1994 that includes most of the skull and teeth, as well as the pelvis, hands, and feet. Ardi had a brain about the same size as a modern bonobo, but much smaller than the brain of australopithecines like Lucy. A. ramidus existed more recently than the most recent common ancestor of humans and chimpanzees, and thus is not fully representative of that common ancestor. Ardipithecus kadabba although known only from teeth and bits and pieces of skeletal bones is a distinct species from A. ramadis, and is dated to approximately 5.6 million years ago.

Ardipithecus ramidus

A ramidus is one of the earliest hominids and reconstructions show a wide range of interpretations of the fossil evidence. Our human phylogeny becomes more enigmatic with so many species existing so close to the origin of hominids suggesting that even then our family tree could be described as bushy, rather than having the single linear progression from species to species that is so often presented in images of human evolution.

Ardipithecus ramidus

Ardipithecus ramidus is about half a million years older than the earliest Australopithecus afarensis and is a bit closer to the last common ancestor between living chimpanzees and humans. This interpretation of Ardi's fossil shows her as an ape-like knuckle-walker contrasting the majority view that she exhibited incipient bipedalism.

Kenyanthropus platyops

K. platyops is a 3.5 to 3.2 million year old (Pliocene) hominin fossil that was discovered in Lake Turkana, Kenya in 1999 by Justus Erus, who was part of Meave Leakey's team. Leaky (2001) proposes that the fossil represents an entirely new hominin genus, while others classify it as a separate species of Australopithecus, Australopithecus platyops, and yet others interpret it as a individual of Australopithecus afarensis. According to anthropologist Daniel Lieberman, multiple species of hominin had been discovered from time periods earlier and later than Lucy and her kin, but the fossil record showed only one ancestor for the middle Pliocene, approximately 3.5 million years ago. Kenyanthropus platyops helps to fill in the picture of this period of evolution, said Lieberman. It indicates that multiple, different-looking species coexisted and filled different ecological niches.

Sahelanthopus tchadensis

S. tchadensis is an extinct hominid species that is dated to about 7 million years ago. Whether it can be regarded as part of the Hominidae tree is unclear; there are arguments both supporting and rejecting it. Another complication in its classification is that it is older than the human-chimpanzee divergence (estimated to 6.3 to 5.4 million years ago) seen in genetic data and that there are few if any specimens other than the partial cranium known as Toumaï.

Sahelanthopus

Sahelanthropus tchadensis is one of the oldest known species in the human family tree. This species lived sometime between 7 and 6 million years ago in West-Central Africa (Chad). Walking upright may have helped this species survive in diverse habitats, including forests and grasslands. Although we have only cranial material from Sahelanthropus, studies so far show this species had a combination of ape-like and human-like features. Ape-like features included a small brain (even slightly smaller than a chimpanzee’s), sloping face, very prominent browridges, and elongated skull. Human-like features included small canine teeth, a short middle part of the face, and a spinal cord opening underneath the skull instead of towards the back as seen in non-bipedal apes. Some of the oldest evidence of a humanlike species moving about in an upright position comes from Sahelanthropus. The foramen magnum (the large opening where the spinal cord exits out of the cranium from the brain) is located furtuer forward (on the underside of the cranium) than in apes or any other primate except humans. This feature indicates that the head of Sahelanthropus was held on an upright body, probably associated with walking on two legs.

Anthropopithecus troglodytes kooloo kamba (Bonobo)

At first assumed to be a slightly smaller sub-species of chimpanzee, the bonobo was originally called a pygmy chimp. A few years after the Belgian discovery, however, the bonobo was accorded its place as a distinct species alongside the other great apes: gorilla, chimpanzee and orangutan. The bonobos body proportions, however, compare more favorably than any other living ape to the 3.2 million-year-old skeletal remains of Australopithecus afarensis, that transitional creature between ape and man that anthropologists named Lucy. About 6 million years ago, the human lineage split off from the rest of the primate family tree. Three million years ago, the bonobo went its separate way.

Common Chimpanzee

Recent DNA evidence suggests the Bonobo and Common Chimpanzee (Pan troglodytes) species separated from each other less than one million years ago (similar in relation between between Homo sapiens and Neanderthals). The chimpanzee line split from the last common ancestor of the human line approximately six million years ago. Because no species other than Homo sapiens has survived from the human line of that branching, both chimpanzee species are the closest living relatives of humans.

Sivapithecus

Ddated from the Middle and Late Miocene epochs (about 16.6 to 5.3 million years ago). Sivapithecus was about 4.9 ft in body length, similar in size to a modern orangutan. In most respects, it would have resembled a chimpanzee, but its face was closer to that of an orangutan. The shape of its wrists and general body proportions suggest that it may have spent a significant amount of its time on the ground, as well as in trees. It had large canine teeth, and heavy molars, suggesting a diet of relatively tough food, such as seeds and savanna grasses. Specimens once assigned to the genus Ramapithecus are now considered by most researchers to belong to one or more species of Sivapithecus. It is no longer regarded as a likely ancestor of humans and may have been the ancestor to the modern orangutans.

Khoratpithecus piriyai

Khoratpithecus piriyai was a Late Miocene hominoid orangutan from northeastern Thailand dating of 9 to 7 million years ago. It is shown here to illustrate the stasis in the evolution of one of multiple branches from a common proconsul ancestry from 18 million years ago. Relative to a contemporary cousin - Sivapithecus, a possible ancestor to modern modern orangutan due to its similar size, K. piriyai examples how species within a shared branch diversify in the rate and direction of evolution. Sahelanthropis tchadenis, a Late Miocene hominoid, was close to our Homo lineage whose common ancestry may also trace back to proconsul and further illustrates how one branch out of many, may exhibit accelerated evolution. Of course an even more dramatic example of a contrast in the rate of evolution between species with common ancestry is the comparison between modern humans and extant Anolis carolinensis - both sharing a common ancestry with a creature resembling Archaeothyris that lived 306 million years ago. While A.carolinensis seems barely evolved from its lizard ancestry, we modern humans have resulted from a vastly accelerated rate (as well as direction) of evolution.

Nakalipithecus nakayamai

N. nakayamai is a prehistoric great ape species that lived in today's Kenya region early in the Late Miocene, 10 million years ago. Nakalipithecus species is very close to the last common ancestor of gorillas, chimpanzees, and humans so may be a basal member of the Homininae. The evolutionary importance of Nakalipithecus that together with Oreopithecus indicates that the Homininae lineages of today diverged no earlier than some 8 million years ago. It also supports the theory that the closest relatives of humans evolved in Africa. It is pictured in incipient bipedal gate similar to that employed by gibbons, lesser apes of SE Asian jungles, when foraging on ground, fording waterways or traversing tree limbs and liana vines. Bipedalism in the earliest hominoids suggests it evolved earlier than Australopithecine venturing onto drier savannas. that triggered an increase in brain size.

Anoiapithecus brevirostris

Researchers have discovered a fossilized face and jaw from a previously unknown hominoid primate genus in Spain dating to the Middle Miocene era, roughly 12 million years ago. Nicknamed 'Lluc', the male bears a strikingly 'modern' facial appearance with a flat face, rather than a protruding one. The finding sheds important new light on the evolutionary development of hominids, including orangutans, chimpanzees, bonobos, gorillas and humans. The find raises the possibility that pongines (orangutans and related forms) and hominines (African apes and humans) separately evolved in Eurasia and Africa, respectively, from different kenyapithecine ancestors.

Oreopithecus bambolii

Oreopithecus is an extinct primate from the Miocene whose fossils have been dated to about 8 mya, found in today's Tuscany and Sardinia in Italy. The lack of predators and the limitation of space and resources in Oreopithecus′ insular environment favored a locomotor system optimized for low energy expenditure rather than speed and mobility. New evidences confirmed that Oreopithecus was bipedal but also revealed that its peculiar form of bipedalism was much different from that of Australopithecus′ — the hallux formed a 100° angle with the other toes enabling the foot to act as a tripod in erect postures — and could not enable Oreopithecus to develop a fast bipedal locomotion. Since the fossils have been dated to about 8 million years ago, this would represent an unusually early appearance of upright posture. However, a reevaluation of the spine from a skeleton of Oreopithecus has led to the conclusion that it may have lacked adaptations for habitual bipedality.

Oreopithecus bambolii

Oreopithecus bambolii evolved in isolation from other animals for at least two million years on an island in the Mediterranean where Tuscany in Italy is found today. A cooling phase around 9 million years ago transformed a tropical island into a temperate one characteristic of middle European biomes at the time. There were no large predators on the island and the apes didn't have any natural enemies. Later, probably during the ice age when the sea level dropped all over the world, a land bridge emerged and connected the island with the mainland. New species, among them large predators, were then free to invade this isolated environment where animals like the Swamp Ape were easy prey.

Dryopithecus aka Hispanopithecus

Dryopithecus laietanus; Late Miocene 12-9.5 Ma - France, Austria, Germany, Hungary & Catalonia - Spain
A hominoid ape nearly as large as a man, Dryopithecus of Lartet, was closely allied to the anthropomorphous Hylobates, existed in Europe during the Late Miocene epoch. Reconstruction in the Institut Català de Paleontologia Miquel Crusafont, in Sabadell, Catalonia.

Pierolapithecus catalaunicus

The 13 Mya fossil hominid, Pierolapithecus catalaunicus, popularly known as Pau, is one of the earliest hominids known. It is located as the common core of descending orangutans, gorillas, chimpanzees, bonobos and humans for understanding the elusive question of the Middle Miocene origin and early radiation of great apes. As many as 100 different ape species roamed the Miocene Old World, from France to China in Eurasia and from Kenya to Namibia in Africa but in Pau's time the Mediterranean Sea was even wider than it is today, so her ancestors must have taken a path through the Middle East to get there.

Proconsul

Proconsul is an extinct genus of primates that existed from 23 to 25 million years ago during the Miocene epoch. Fossil remains are present in Eastern Africa including Kenya and Uganda. Four species have been classified to date: P. africanus, P. heseloni, P. major and P. nyanzae. The four species differ mainly in body size. Environmental reconstructions for the Early Miocene Proconsul sites are still tentative and range from forested environments to more open, arid grasslands. The gibbons, great apes and humans share a common ancestral lineage, which may have included Proconsul. Its name means 'ancestor to the chimpanzee', which if true would also make it ancestor to the rest of the apes. Proconsul likely evolved incipient bipedalism in forest environs much as some of today's lesser apes such as gibbons Barbari apes and black macaques exhibit when traversing vines, tree branches, waterways and tall grassland.

Proconsul africanus (Hopwood, 1933)

The 18-million-year-old fossil species has been considered a possible ancestor of both great and lesser apes, and of humans but the exact classification of Proconsul currently favors a position between the monkeys and the apes.

proconsul africanus

Extinct Primates

top: (Section of mural at AMNH (by J.H. Matternes http://www.jay-matternes.com) depicts [from left]: putative orangutan relative Sivapithecus - proconsul - squirrellike Plesiadapis ) Image at right - ramapithecus. bottom: dryopithicus - pliesiadapis (by Keiji Terakoshi http://www.terakoshi.com/Enindex.html) Image at right - tarsierfoss While most living primates fall fairly neatly into two main groups- the Strepsirrini (the suborder that embraces lemurs, lorises and galagos) and the Haplorrhini (the one that includes monkeys,apes and humans) - tarsiers seem to belong to both at once. Their lineage is believed to have separated from all other Haplorrhini as early as 78 Mya.

Miocene Epoch

The Miocene is a geological epoch of the Neogene Period and extends from about 23.03 to 5.33 million years before the present. The Miocene follows the Oligocene Epoch and is followed by the Pliocene Epoch. The Miocene is the first epoch of the Neogene Period. The Earth went from the Oligocene Epoch through the Miocene and into the Pliocene as it cooled into a series of Ice Ages. Of the modern geologic features, only the land bridge between South America and North America was absent.

Notharctus tenebrosus

With the beginning of modern climates, marked by the formation of the first Antarctic ice in the early Oligocene around 30 million years ago. A primate from this time was Notharctus. Fossil evidence found in Germany in the 1980s was determined to be about 16.5 million years old, some 1.5 million years older than similar species from East Africa and challenging the original theory regarding human ancestry originating on the African continent.

Aegyptopithecus

About 37 million years ago, the primates split into two branches that evolved separately, the prosimians and the anthropoids. The prosimians evolved into the present-day lemurs, eye-eyes, lorises, bush babies, and tarsiers. Anthropoid primates resembling some current monkeys first appeared about 37 million years ago, near the end of the Eocene epoch. Early anthropoids were arboreal and vegetarian. They lived in forests, ate mostly seeds and fruits, and had tails, shorter snouts and forward-looking eyes. During the Oligocene epoch, 34 to 23 million years ago, newly-evolved monkey species replaced many of the older primates, the prosimians. Some early monkeys, like Aegyptopithecus, were larger than their prosimian ancestors and weighed about 16 pounds. Anthropoids developed independently in the separated African and South American continents. Two types emerged, the New World monkeys, the platyrrhini, and the Old World monkeys, the catarrhini.

Weasel Lemurs

The evolutionary history of lemurs occurred in isolation from other primates on the island of Madagascar for at least 40 million years. Lemurs are prosimian primates belonging to the suborder Strepsirrhini, (lemurs, lorises, galagos, aye-aye, and relatives) which branched off from other primates less than 63 mya (million years ago). They share some traits with the most basal primates, and thus are often confused as being ancestral to modern monkeys, apes, and humans. Instead, they merely resemble ancestral primates.

Aye aye

The Aye-aye (Daubentonia madagascariensis) is a lemur, a primate native to Madagascar that combines rodent-like teeth with a long, thin middle finger to fill the same ecological niche as a woodpecker. Due to its derived morphological features, the classification of the Aye-aye has been debated since its discovery. The possession of continually growing incisors (front teeth) parallels those of rodents, leading early naturalists to mistakenly classify the Aye-aye within mammalian order Rodentia. The Aye-aye's classification with the order Primates has been just as uncertain. It has been considered of indeterminate relation to all living primates. In 2008, the Aye-aye family (Daubentoniidae) was confirmed to be mostly closely related to the Malagasy lemurs, likely having descended from the same ancestral population that colonized the island.

Galago senegalensis PT (Bush Baby)

May be a living primate with superficial features closely resembling one of our early ancestral primate relatives. A low-coverage genomic sequence of the Northern Greater Galago, Otolemur garnettii, is in progress. As it is a 'primitive' primate, the sequence will be particularly useful in bridging the sequences of higher primates (macaque, chimp, human) to close non-primates such as rodents.

Chesapeake Impact

An artist's rendering shows a giant asteroid or comet plunged into Earth near what is now the Chesapeake Bay 35 million years ago. Researchers are simulating comet impacts to see if they might help proliferate the left-handedness in molecules that life on Earth depends upon. There is evidence from meteorite studies that amino acids may have been delivered repeatedly to early Earth from space.

Early Oligocene - N. America

The transition from the Eocene to the Oligocene epoch, occurring approximately 47 to 30 million years ago, was the most dramatic episode of climatic and biotic change since the demise of the dinosaurs. The mild tropical climates of the Paleocene and early Eocene were replaced by modern climatic conditions and extremes, including glacial ice in Antarctica. http://en.wikipedia.org/wiki/Oligocene The Terrestrial Eocene-Oligocene Transition in North America: This book summarizes the latest information in the dating and correlation of the strata of late middle Eocene through early Oligocene age in North America.

Oligocene Epoch

The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present. The name Oligocene comes from the Greek (oligos, few) and (kainos, new), and refers to the sparsity of additional modern mammalian faunas after a burst of evolution during the Eocene. The Oligocene follows the Eocene Epoch and is followed by the Miocene Epoch. The start of the Oligocene is marked by a major extinction event, a faunal replacement of European with Asian fauna except for the endemic rodent and marsupial families called the Grande Coupure. During this period, the continents continued to drift toward their present positions. There appears to have been a land bridge in the early Oligocene between North America and Europe since the faunas of the two regions are very similar.

Middle Eocene - N. America

The global warming events that heralded the onset of the Eocene caused tropical habitats in the interior of North America to deteriorate creating more open woodlands beginning about 42 million years ago.
See Species Legend: http://maya-gaia.angelfire.com/middle_eocene_text.html http://linkinghub.elsevier.com/retrieve/pii/S003101821000458X The Eocene Epoch, lasting from about 56 to 34 million years ago, is a major division of the geologic timescale and the second epoch of the Paleogene Period in theCenozoic Era. The start of the Eocene is marked by the emergence of the first modern mammals. The end is set at a major extinction event called Grande Coupure (the 'Great Break' in continuity), which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay.

Cenozoic Era

The Cenozoic Era is the most recent of the three classic geological eras and covers the period from 65.5 million years ago to the present. It is marked by the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and the end of the Mesozoic Era. In the earlier part of the Cenozoic, the world was dominated by the birds, terrestrial crocodiles and a handful of primitive large mammal groups But as the forests began to recede and the climate began to cool, during the Cenozoic, mammals diverged from a few small, simple, generalized creatures into a diverse collection of terrestrial, marine, and flying animals. Pictured in foreground are one of many species of small protoprimates radiating out from Plesiadapis-type ancestors.

Paleocene-Eocene Thermal Maximum - Detail 1

...56 mya a mysterious surge of carbon into the atmosphere sent global temperatures soaring. In a geologic eyeblink life was forever changed. Earth was hot and free of ice at the end of the Paleocene epoch, with sea level 220 feet higher than now, the Americas not yet joined were smaller. Scientists call this fever period that lasted 150,000 years the Paleocene-Eocene Thermal Maximum, or PETM and it triggered an explosion of mammalian evolution.

Paleocene-Eocene Thermal Maximum - Detail 2

...56 mya the carbon released in the atmosphere equaled that which would result if Earth's total fossil fuel reserve were used up in 100 years - temperatures at the North Pole hit 74 degees F. Humans, along with every primate living tody, are descended from a PETM primate- just as perissodactyl such as horses, camels and rhinos are descended from another PETM ancestor, and ruminants such as deer, cows and sheep from still another. Some species that suddenly showed up in North America may have migrated from Asia across a forested arctic landbridge.

Darwinius masillae ('ida')

Darwinius masillae named 'Ida', a 47-million-year-old primate skeleton of an immature female from Messel, Germany represents the most complete fossil primate ever found, including both skeleton, soft body outline and contents of the digestive tract.

Darwinius masillae

Scientists have presented D. masillae, a superbly preserved fossil from the world famous Messel fossil site in Germany, as evidence to support the idea that anthropoids could have evolved from adapoids, a group of arboreal quadrupeds that lived over 55 million years ago. On the other side of the debate are scientists who see evidence that the adapoids were the ancestors of lemurs and lorises, not anthropoids. Instead, they argue that the ancestor of anthropoids evolved from the omomyoids, another group of arboreal quadrupeds that lived at the same time as the adapoids during the Paleocene and Eocene epochs (66 to 35 million years ago).

Andrewsarchus

Mesonychia ('Middle Claws') are an extinct order of medium to large-sized carnivorous mammals that were closely related to artiodactyls (even-toed ungulates), and to cetaceans (dolphins and whales). Some experts unite Mesonychia with the whales to form the clade 'Cete'. They first appeared in the Early Paleocene and went into a sharp decline at the end of the Eocene and died out entirely when the last genus, Mongolestes became extinct in the Early Oligocene

Carpolestes

We're getting close to your ultimate primate grandparents. But first, meet one of your most primordial ancestors, who may have looked like this mole-sized critter. Your Ancestor's Profile. Carpolestes is a very early (55 Mya) primate, but it has features that set it apart from the most primitive primates of all, including a nail rather than a claw on its big toe.

Pen-Tailed Tree Shrew

The Pen-tailed Treeshrew (Ptilocercus lowii) is the extant species with the closest resemblance to our earliest primate ancestor- Dryomommys. It is a species of treeshrew in the Ptilocercidae family found in Indonesia, Malaysia, and Thailand. The Pen-tailed Treeshrew exhibits an instinct very close to our human nature as it is one of seven known wild mammals that chronically consume alcohol. A study of the treeshrew in Malaysia found that it spends several hours consuming the equivalent of 10 to 12 glasses of wine with an alcohol content of up to 3.8% every night drinking naturally-fermented nectar of the bertam palm. Despite consuming relatively large amounts of alcohol, the Pen-tailed Treeshrew does not become intoxicated. Measurements of a biomarker of ethanol breakdown suggest that they may be metabolizing it by a pathway that is not used as heavily by humans.

Dryomomys

Dryomomys is the most primitive primate known from good fossil material. (The first known primate, Purgatorius, dating back as far as 65 million years ago, is known only from isolated teeth and jaw fragments.) The animal most like Dryomomys today is a wee being called the pen-tailed tree shrew. We've now arrived at one of your very earliest precursors, 55 million years ago. Something like this creature begot something that begot something that, after that eternity of time, begot you.

Leptictidium

Leptictidium was a prehistoric mammal (a leptictidan). It was a small leptictidan mammal from the early Eocene (56-40 million years ago) that hopped like kangaroos do today, but it was a placental (eutherian, thought Leptictidium and kin are outside placentalia, which includes all modern placentals) mammal that is not closely related to any of the modern species. Hopping aside, in the front Leptictidium resembled the modern elephant shrews or sengus, primitive mammals, which can still be found today mostly in the African savanna. In the first episode of Walking with Beasts, a female Leptictidium was shown caring for her partially grown-up young and was the main mammalian focus of the episode, illustrating the development of the first mammals after the extinction of the dinosaurs in the K-T extinction event.

Cenozoic Placental

After an asteroid killed off the dinosaurs — save for those that evolved into today's birds — a small, furry animal scurried through the forest and climbed trees in search of insects. Its unassuming looks gave little hint that its mammalian descendants - including bats, whales and us - would one day rule the planet. Scientists reconstructed the appearance and anatomy of this creature - the forebear of all 'placental' mammals, which give birth to live young at an advanced stage of development - rendered in unprecedented detail by paleo artist Carl Buell. The analysis confirms that the placentals diversified a few hundred thousand years after the (non-avian) dinosaurs went extinct, so groups such as rodents and primates never shared the planet with the prehistoric reptiles. This conclusion contradicts genetic studies that put the group's origin at around 100 million years ago in the Cretaceous.

Scene at the end of the Cretaceous- our mammalian ancestors, having survived the great extinction, foraging a Triceratops skull.

Extinction

Non-avian dinosaur fossils are found only below the K–T boundary indicating that non-avian dinosaurs became extinct immediately before, or during the Cretaceous mass extinction event. A very small number of dinosaur fossils have been found above the K–T boundary (K is the traditional abbreviation for the Cretaceous period, and T is the abbreviation for the Tertiary period). Today, many scientists think the evidence indicates a sixth mass extinction is under way. The blame for this one, perhaps the fastest in Earth's history, falls firmly on the shoulders of humans. By the year 2100, human activities such as pollution, land clearing, and overfishing may have driven more than half of the world's marine and land species to extinction.

Deccan Traps

A current theory about the end of the non avian dinosaurs is that extinction was accelerating near the end of the Cretaceous likely because of climatic stress caused by the ongoing series of massive volcanic eruptions in India called the Deccan Traps and other factors including the Chicxulub impact event in Central America which hit the Yucatan about 300,000 years before the last of the dinosaurs vanished. The quantity of gas injection from the main phase of Deccan eruptions was 30 to 100 times larger than the Chicxulub impact and occurred over as little as 10,000 to 100,000 years, with each pulse lasting about 10 years or more. At least four additional massive Deccan eruptions about 200 Ky after the KT extinction delayed the recovery of Earth's ecosystem and the radiation of mammals for another 300 Ky.

End of the Cretaceous

Early mammals, Pliesiadapis forage the remains of a victim of the great extinction.

Chicxulub Asteroid Impact

Scientists had theorized that the K–T extinctions were caused by one or more catastrophic events, such as massive asteroid impacts or increased volcanic activity. Several impact craters and massive volcanic activity, such as that in the Deccan traps, have been dated to the approximate time of the extinction event. These geological events may have reduced sunlight and hindered photosynthesis, leading to a massive disruption in Earth's ecology. Other researchers believe the extinction was more gradual, resulting from slower changes in sea level or climate. On March 4, 2010, a panel of 41 scientists agreed that the Chicxulub asteroid impact triggered the mass extinction.

K-T Extinction Event

An intimate drama in the daily hazards our mammalian ancestors survived is depicted 65 Mya at the moment a major extinction event will cause the demise of the non-avian dinosaurs and give rise to the mammalian lineage resulting in us.

K-Pg Extinction Event

The Cretaceous–Paleogene (K–Pg) extinction event, formerly known as the Cretaceous–Tertiary (K–T) extinction, was a mass extinction of some three-quarters of plant and animal species on Earth—including all non-avian dinosaurs—that occurred over a geologically short period of time, 66 million years ago. It marked the end of the Cretaceous period and with it, the entire Mesozoic Era, opening the Cenozoic Era that continues today. Some scientists maintain the extinction was caused or exacerbated by other factors, such as volcanic eruptions, climate change, or sea level change, separately or together. Yet the devastation caused by the extinction also provided evolutionary opportunities for our mammalian ancestors who radiated into primates and eventually into our hominid lineage.

Cretaceous Life

This rendering of Cretaceous life shows the diverse range of dinosaurs that lived between 145 and 65 million years ago, including maiasaurs (front left); tarbosaurs (top right), and pterosaurs (top center). In the foreground are depicted the first flowering plants which developed during this period and one of the earliest mammal relatives which went on to survive the dinosaur extinction at the end of the Cretaceous.

Mosasaurs

During the last 20 million years of the Cretaceous Period, with the extinction of the ichthyosaurs and pliosaurs, mosasaurs became the dominant marine predators. They shared the fate of the dinosaurs in the Cretaceous-Tertiary extinction event. These ferocious marine predators are now considered to be the closest relatives of snakes.

Herrerasaurus and Megazostrodon

Herrerasaurus is depicted lurking in a forest in what is now Argentina as megazostrodon (early mammaliaform) hide in the undergrowth. Herrerasaur fossils are among the oldest ever discovered, dating back about 228 million years to the mid-Triassic.

Cimolestes

Cimolestes (Bug Thief) a genus of early eutherians whose species are found primarily in North America, where they first appeared during the Late Cretaceous, and died out during the Paleocene. Insectivore-like mammals have long been known to occur in the Late Cretaceous. Cimolestes, for instance, flourished in the Latest Cretaceous of North America, and this archaic genus even made it into the Early Paleocene. Most species of Cimolestes were mouse- to rat-sized, but the Late Cretaceous Cimolestes magnus reached the size of a marmot, making it one of the largest Mesozoic mammals known. Closest living relative- Pangolin.

Cretacious Mammals

top: Purgatorius - Maotherium
middle: Ralambdelestes - Alphadon
bottom: Jeholodens - Repenomamus
A new statistical method (2002), based on an estimate of species preservation derived from a model of the diversification pattern, suggests a Cretaceous last common ancestor of primates, approximately 81.5 Myr ago, close to the initial divergence time inferred from molecular data. It also suggests that no more than 7% of all primate species that have ever existed are known from fossils.

Sinodelphys szalayi

S. szalayi, also known as Chinese opossum, is an extinct creature with close affinities with the family of mammals known as metatherians, which includes the marsupials. It is the oldest metatherian fossil known, estimated to be 125 million years old and lived next to the dinosaurs. In 2002, Co-author of the Science paper Dr Zhe-Xi Luo, curator of vertebrate palaeontology at the Carnegie Museum of Natural History also described the earliest fossil placental mammal - Eomaia scansoria - which was discovered in the same quarry in northeastern China as Sinodelphys.

Triconodon

Genus of extinct mammals found in European deposits of the late Jurassic Period (about 161 million–146 million years ago). Triconodon is representative of the triconodonts, known from fossils throughout North America, Europe, Africa, and China. About the size of a domestic cat. Triconodonts also known as Eutriconodonta)- a group of early mammals which were close relatives of the ancestors of all present-day mammals. Triconodonts lived between the Triassic and the Cretaceous. They are one of the groups that can be classified as mammals by any definition. Several other extinct groups of Mesozoic animals that are traditionally considered to be mammals (such as Morganucodonta and Docodonta) are now placed just outside Mammalia.

Gobicondon - a Triconodont

A carnivorous mammal that belonged to the Triconodonta (also known as Eutriconodonta) the generic name for a group of early mammals that lived between the Triassic and Cretaceous which were close relatives of the ancestors of all present-day mammals. It weighed 10–12 pounds and measured 18-20 inches, and might have resembled a large and robust opossum. They are one of the groups that can be classified as mammals by any definition. Several other extinct groups of Mesozoic animals that are traditionally considered to be mammals (such as Morganucodonta and Docodonta) are now placed just outside Mammalia by those who advocate a 'crown-group' definition of the word 'mammal'. They had the typical morphology of the proto-mammals: small, furry, tetrapod animals with long tails. They probably had a nocturnal life style to avoid dinosaur predators, coming out from their burrows after dusk to hunt for small reptiles and insects.

Jurassic Landscape

Depicting a clash between Jurassic dinosaurs Apatosaurus and Saurophaganax (a carnivorous dinosaur similar to Allosaurus). Other animals depicted include Stegosaurus, Camptosaurus, Archaeopteryx and an early possum-like mammal. Karen Carr's Jurassic mural at the Sam Noble Oklahoma Museum of Natural History is two stories tall and more than 60 feet in length.

Honey Possum

Bearing a strong resemblance to its insectivore ancestors that survived the KT extinction, an Australian honey possum pollinates a mottlecah eucalyptus as it feeds on nectar. Two billion years after single-celled life first appeared, muticellular organisms- plants and animals began their symbiotic partnerships when cyanobacteria raised the oxygen level of Earth's atmosphere to where advanced life forms could flourish. Most dramatic in this co-evolution was the appearance of flowering plants 130 Mya in the Lower Cretaceous. This provided the nutrition essential for the insectivore mammal evolution and later in the Cenozoic for the exponential acceleration of mammalian radiation. Walter Judd, a botanist at the U. of Florida says, 'If it weren't for flowering plants, we humans wouldn't be here'

Flowering Plants

The angiosperms, as botanists call the plants that form flowers and encased seeds were believed to be already diverse and found in most locations by the middle of the Cretaceous period… 146 million years ago. Flowers changed everything. They appeared and spread over the Earth with stunning rapidity coevolving with insects to evoke a diversity of insectvore mammaliaforms and mammals. The latter survived the extinction event that wiped out the dinosaurs and in a radiation bloom- produced the primates that resulted in our homonid evolution. Without the food resources that grasses and other flowering plants provided directly or as food for prey animals- we humans would not exist.

Stout, 4/17/06, 11:27 AM, 8C, 7240x11302 (1228+242), 150%, July30Curve, 1/100 s, R55.5, G49.4, B69.1

Castorocauda

Castorocauda is a genus of small, semi-aquatic relative of mammals living in the mid Jurassic period, around 154 million years ago, found in lakebed sediments of the Daohugou Beds of Inner Mongolia. It was highly specialized, with adaptations evolved convergently with those of modern semi-aquatic mammals such as beavers, otters, and the platypus. Because few fossilized remains had been found, it was previously thought that, until the KT boundary, all mammals were tiny, ground-dwelling or tree-dwelling, nocturnal animals akin to shrews, hedgehogs, treeshrews, or tenrecs. This notion has now been falsified by the armadillo-like Fruitafossor, the dinosaur-eating Repenomamus, the flying squirrel-like Volaticotherium and now the otter-like Castorocauda.

Jurassic Landscape

The Jurassic period (199.6 million to 145.5 million years ago) was characterized by a warm, wet climate that gave rise to lush vegetation and abundant life. Archaeopteryx is shown threatening a mammaliform in an unlikely encounter in broad daylight.

Yanoconodon

Yanoconodon is an early mammal whose representative species Yanoconodon allini lived 125 million years ago during the Early Cretaceous in what is now China. It is considered to be a transitional fossil due to the formation of its middle ear, which is a cross between those of modern mammals and their nearest relatives, the mammaliaformes. Yanoconodon was a small mammal, barely 5 inches long. It was lightly-built and probably fed on insects, worms and other invertebrates. Like other Eutriconodonts, Yanoconodon probably hunted at night out of the danger posed by predatory dinosaurs during the day, like most early mammals.

Steropodon

A Monotremes from the early Cretaceous Period. A mammal-like reptile whose fossils were discovered in Australia in 100 million-year-old strata.

Fleeing Nothosaurs

An artist's rendering shows hatchling nothosaurs heading for the safety of water as a hungry but terrestrial Ticinosuchus attacks near a lagoon in ancient Switzerland. Nothosaurs lived during the mid- and late Triassic period and were among the earliest reptiles to take to the sea.

Eomaia

Eomaia ('dawn mother') is an extinct fossil mammal, discovered in rocks that were found in the Yixian Formation, Liaoning Province, China, and dated to the Lower Cretaceous about 125 million years ago. The fossil is 3.9 in in length and although the fossil's skull is squashed flat, its teeth, tiny foot bones, cartilages and even its fur are visible. It is a eutherian, a member of a group of mammals consisting of placental mammals plus all extinct mammals that are more closely related to living placentals (such as humans) than to living marsupials http://en.wikipedia.org/wiki/Eomaia. A contrary view is that the living insectivores and their close fossil relatives form a separate branch on the evolutionary tree of the placental mammals, just like the rodents or the primates, and should not be mixed up with unrelated archaic mammals.

Hadrocodium wui

This miniature Jurassic mammal lived almost 200 million years ago and is one of the closest known relatives to living mammals. It's ancestors survived another major extinction event that occurred between the Late Triassic and Early Jurassic periods.

Triassic Dinosaurs

The burst of new life that occurred in the early- to mid-Triassic period. Massive extinctions at the end of the preceding period gave rise to dinosaurs, pterosaurs, early crocodilians and a thriving diversity of early mammals issuing from mammaliforms that arose in the late Permian.

Mesozoic Mammals and Mammaliaforms

(Showing three reconstruction versions from the fossil evidence for Megazostgrodon)
top: Oligokyphus - Sinoconodon
middle: Megazostrodon1 - Cynognathus - Morganucodon
bottom: Megazostrodon2 - Halanodon - Megazostrodon3

Dvinia prima

The cynodont Dvinia was a therapsid mammal-like 'reptile' of the family Dviniidae found in Sokolki on the Northern Dvina River near Kotlas in Arkhangelsk Oblast, Russia. Its fossil remains date from the Late Permian and were found with Inostrancevia, Scutosaurus and Dicynodon trautscholdi. The species was small omnivore containing an extremely large temporal opening typical of advanced therapsids, with a thin bone separating the eye and muscle attachment. It is very close in the evolutionary line to mammals.

Fortunodon trautscholdi Encounters Dvinia prima

Fortunodon trautscholdi is an extinct terapsid dicynodon that lived in the Upper Permian (about 257-252 million years ago) found in Russia. Some features of vivaxosaurus, mainly the pectoral girdle, strong forelimbs, and horny beak like that of a turtle suggests it fed on roots, which were unearthed by the powerful legs. Dvinia was a therapsid mammal-like 'reptile' of the family Dviniidae -a small omnivore containing an extremely large temporal opening typical of advanced therapsids, very close in the evolutionary line to mammals whose fossil remains were found with Dicynodon trautscholdi.

Permian Extinction Event

The Siberian Traps form a region of volcanic rock in Russia. The super-massive eruptive event 250 Mya, continued for a million years and spanned the Permian-Triassic boundary. It is considered to be the likely cause of this 'Great Dying'. http://en.wikipedia.org/wiki/Siberian_Traps This was Earth's most severe extinction event available from the fossil records, with up to 96 percent of all marine species and 70 percent of terrestrial vertebrate species becoming extinct; it is the only known mass extinction of insects. After the extinction, one genus of land vertebrate dominated: a medium-sized herbivore called Lystrosaurus. Only one genus of sea life is common after the extinction as well: a brachiopod called Lingula. Veranops- considered one of our basal reptilian-mammaliaforms from the Perman is pictured about to be consumed by a pyroclastic flow.

Varanops

Varanops is an extinct genus of Early Permian varanopid synapsid known from Texas and Oklahoma of the United States. As a late surviving member of the group,‭ ‬Varanops is often cited as one of the last of the pelycosaur carnivore that dominated the Permian Period.‭ ‬With its relatively long legs,‭ ‬Varanops may have been more suited to open ground,‭ ‬as opposed to dense undergrowth where they may have been of a hindrance.‭ ‬They may have also provided for sudden bursts from an ambush point if Varanops employed ambush tactics as a hunting strategy. Varanops did not survive to see the Permian extinction,‭ ‬and is thought to have succumbed to competition from both the diapsids and therapsids that were becoming more common,‭ ‬and more capable predators.

Cynognathus

Cynognathus- Phylogeny Order Therapsida- was a metre-long predator of the Lower Triassic. It was one of the more mammal-like of the 'mammal-like reptiles', a member of a grouping called Eucynodontia. Cynodontia or cynodonts ('dog teeth') are a taxon of therapsids endemic to all seven continents beginning during the Early Triassic 256 Ma that bridged the Permian mass extinction. This taxon includes modern mammals and their extinct close relatives. They were one of the most diverse groups of therapsids.

Permian River Mural

A pair of Dimetrodon contest over a meal of Diplocaulis as Edaphosaurus and other vegetarian Pelycosaurs look on.

Permian River Mural

A pair of Dimetrodon contest over a meal of Diplocaulis. Some Pelycosaur is thought to be a direct antecedent of mammals.

Gorgonops

Gorgonops (literally 'Gorgon' face) is the name given to an extinct genus of therapsid which lived about 255-250 million years ago, during the latest part of the Permian Period. It was a typical representative of the Gorgonopsia, the dominant predators of their day, which in the largest forms grew to over four meters long. They shared a common descendant with reptiles, but were on a line that gave rise to mammals rather than dinosaurs, lizards, turtles or birds. They were wiped out in the world's most severe extinction, the Permo-Triassic mass extinction that killed 80 percent to 90 percent of all species on Earth.

Inostrancevia

An iconic image - evoking the brutal reality of the unending struggle for survival between predator and prey that has been an ongoing dynamic in the evolution of life since the peaceable kingdom of the Precambrian Ediacaran, between 600 million and 540 million years ago. Then - no predators hunted with claws and teeth; softer, economical life styles prevailed. The species in Inostrancevia lived in Russia during the Late Permian period, dating from approximately 260 to 254 mya. and were the largest gorgonopsids known. Individuals had total body lengths reaching up to 11 ft 6 in. Like several other gorgonopsids, Inostrancevia was characterized by strongly developed canine teeth, with those of the upper jaw up to 5.9 in long, the root corresponding to half its length. Scutosaurus was a plant eater that had rows of hard, bony plates (scutes) underneath the skin that acted like a form of chain mail that did not always defend against predation by a determined gorgonopsid carnivore.

Lystrosaurus

About the size and weight of a small pig, Lystrosaurus is from a taxon of therasids or mammal-like reptiles from the Permian that survived the great extinction event 300 Mya to dominate southern Pangea during the Early Triassic, for millions of years. In the absence of predators and other herbivorous competitors, it went on to thrive and re-radiate into a number of species within the genus, becoming the most common group of terrestrial vertebrates during the Early Triassic. For a while 95% of land vertebrates were Lystrosaurus.

Permian Seafloor

The Permian period saw the creation of the supercontinent Pangaea, where shallow seas in and around the huge landmass offered a home to an abundance of life. This diorama at the University of Michigan's Museum of Natural History shows some of the flora and fauna that thrived in Permian seas, including trilobites, gastropods, clams, nautiluses, and corals.

Edaphosaurus

Edaphosaurus is a genus of prehistoric reptile which lived around 303 to 299 million years ago, during the late Carboniferous to early Permian periods. Edaphosaurus is one of the earliest known large plant-eating pelecosaur (sailback) tetrapods. Early descriptions, referring to its sharp teeth, suggest that the reptile may have fed on small invertebrates, such as mollusks, although paleontologists now point out that Edaphosaurus also shows herbivore characteristics. It may have been prey for the fierce carnivorous pelecosaur Dimetrodon.

Permian Therapsidia

top: Veranops - Gorgonops
bottom: Procynosuchus - Dimetrodon
(Veranops is thought to be the basal Therapsid in the Cynodont to mammaliaform lineage and therefore very close to our reptilian ancestor.)

Proterogyrinus Fights Aarthropleura

Proterogyrinus was an anthracosaur, which means it belonged to a group of advanced amphibians- also referred to as reptiliomorphs or basal reptiles from the Upper Carboniferous. Proterogyrinus, like other reptiliomorphs, could venture further away from water than amphibians, but still had to stay reasonably close by the water. In 'Walking with Monsters', a Proterogyrinus was depicted fighting an Arthropleura (giant millipede).

Carboniferous to Permian Continental Drift

During the Carboniferous (bottom), the hot, humid climate supported vast forests of giant club mosses and ferns in Gondwanaland for millions of years. By the time the land masses had drifted northward and consolidated into Pangea in the Permian (top), biota had evolved to adapt to the cooler climate and vast deserts spreading over the landscape.

Mesothelae Stalks Petrolacosaurus

Mesothelae was depicted as a human head sized spider from the Carboniferous period in 'Walking with Monsters' shown hunting lizards such as Petrolacosaurus, one of the first reptiles. Its fossil is now known to have been a sea scorpion that lived in swamps; however, this was not found out until after animation for the series had been finished.

Extant Anolis carolinensis (male-female)

It would take a high degee of paleontological skill to differentiate future partial fossil remains among Archaeothyris and Holonomis and a variety of extant anoles and other small reptiles such as these A. carolinensis specimens that seem to have not evolved at all from their ancestors from over 312 Mya.

Hylonomus lyelli

Hylonomus is the oldest vertebrate recognized as a reptile. Unlike most of the amphibians, these animals were generally not tied to water for reproduction, but laid eggs that were able to survive in a terrestrial environment. Hylonomus had an unbroken expanse of bone behind each eye opening. Other reptiles had one or more gaps, the temporal openings, occupying various positions and enclosed by various bones. Though these patterns vary in details, the gaps themselves - or the lack of them - are the basis for splitting the reptiles into four major groups.

Hylonomis

Hylonomus was a very early reptile. It lived 312 million years ago during the Late Carboniferous period. As of 2006, it is the earliest confirmed reptile.

Archaeothyris

Archaeothyris was a very early mammal-like reptile, which lived in the late Carboniferous period. Dated to 306 million years ago, it is the oldest undisputed synapsid known and belonged to the series of primitive synapsids which are conventionally grouped as pelycosaurs. Synapsids ('fused arch') are a class of animals that includes mammals and everything more closely related to mammals than to other living amniotes. More advanced mammal-like synapsids are called therapsids. Synapsids are one of the two major groups of the later amniotes, the other being the sauropsids (reptiles and birds).Today, there are 5,400 species of living synapsids known as the mammals, including both aquatic (whales) and flying (bats) species). Humans are synapsids as well.

Carboniferous Swamp

Characteristic of the Carboniferous period (from about 360 million to 300 million years ago) were its dense and swampy forests, which gave rise to large deposits of peat. Over the eons the peat transformed into rich coal stores in Western Europe and North America. The name 'Carboniferous' refers to this coal.

Carboniferous Forests

Varanops is an extinct genus of Early Permian varanopid synapsid known from Texas and Oklahoma of the United States. As a late surviving member of the group,‭ ‬Varanops is often cited as one of the last of the pelycosaur carnivore that dominated the Permian Period.‭ ‬With its relatively long legs,‭ ‬Varanops may have been more suited to open ground,‭ ‬as opposed to dense undergrowth where they may have been of a hindrance.‭ ‬They may have also provided for sudden bursts from an ambush point if Varanops employed ambush tactics as a hunting strategy. Varanops did not survive to see the Permian extinction,‭ ‬and is thought to have succumbed to competition from both the diapsids and therapsids that were becoming more common,‭ ‬and more capable predators.

Mississippian Marine Life

Mississippian marine life was marked by extensive shallow reef communities, including Crinoids- members of the phylum Echinodermata. This is the phylum that brings you starfish, sea urchins, and sand dollars. The crinoids are a breed apart however, they resemble an underwater flower. Some even have parts that look and act like roots anchoring them to the ocean floor. They are commonly called sea lilies.

Early Amphibian

Sterkfontein Exhibition

Pennsylvanian Period Life

With much more land surface exposed in the Pennsylvanian time, as compared to the Mississippian time, extensive tropical forests were formed. These would eventually be fossilized into extensive coal deposits in Pennsylvania as well as other parts of the world.

Tetrapod Evolution

top: pederpes
middle: hynerpeton - seymouria Fossil
bottom: panerichthys
Pederpes is the most basal Carboniferous tetrapod and is the earliest-known tetrapod to show the beginnings of terrestrial locomotion and despite the probable presence of a sixth digit on the forelimbs it was at least functionally pentadactyl. The so-called Romer's gap is the 20 million year period which separates the Late Devonian early tetrapod fossil record to the middle Carboniferous one, where no tetrapod fossil has been found until Pederpes. Contrary to the polydactyl late devonian tetrapods, it had robust 5-digit feet.

Acanthostega

Acanthostega (meaning Spiny Roof) is an extinct tetrapod genus, among the first vertebrate animals to have recognizable limbs. It appeared in the Upper Devonian (Famennian) about 365 million years ago, and was anatomically intermediate between lobe-finned fishes and the first tetrapods fully capable of coming onto land.

Diplocaulus magnicornis

An early permian lepospondyli known for the long protrusions on the sides of its skull, which cause the skull to be shaped similar to a boomerang. Judging from its weak limbs and relatively short tail, it is presumed to have swum with an up-and-down movement of its body, not unlike cetaceans today. The wide head could have helped the creature glide through the water. Also, it is thought to have had defensive purposes as any predator (even the large-headed Eryops) would have a hard time trying to swallow a creature with such a wide head.

Amphibamus

Amphibamidae is an extinct family of dissorophoid Euskelian Temnospondyls. Amphibamus grandiceps, a dissorophoid - Late Carboniferous (Moscovian) of Illinois. This animals is considered to have been close to the ancestry of modern amphibians. Length about 20 cm.

Carboniferous Amphibians

top: Silvanerpeton
middle: Ophiderpeton - Balanerpeton
bottom: Microbrachis
Fossil remains of air-breathing insects, myriapods and arachnids are known from the late Carboniferous, but so far not from the early Carboniferous. Amphibians were diverse and common by the middle of the period; some were as long as 6 meters. One of the greatest evolutionary innovations of the Carboniferous was the amniote egg, which allowed for the further exploitation of the land by certain tetrapods. These included the earliest sauropsid reptiles (Hylonomus), and the earliest known synapsid (Archaeothyris). These small lizard-like animals quickly gave rise to many descendants and by the end of the Carboniferous period, reptiles underwent a major evolutionary radiation, possibly in response to an increasingly drier climate.

Tiktaalik

Tiktaalik is a genus of extinct lobe-finned fish that lived approximately 375 million years ago from the late Devonian period, with many features akin to those of tetrapods (four-legged animals). It is an example from several lines of ancient fish developing adaptations to the oxygen-poor shallow-water habitats of its time, which led to the evolution of amphibians. Paleontologists suggest that it is representative of the transition between fish such as Panderichthys, known from fossils 380 million years old, and early tetrapods such as Acanthostega and Ichthyostega, known from fossils about 365 million years old.

Late Devonian River Scene - Pictured: Eusthenopteron, Diplacanthus, Acanthostega, Bothriolepis, Rhacophyton

Somewhere between the Early and Middle Devonian Periods, one of the five major mass extinctions occurred, mainly effecting marine life, whose cause is open to wide speculation.

Lobe-fin Fish

Lobe-fin fishes form one of the two known lineages of bony fishes (the Osteichthyes). Ray-fin fishes (Actinopterygii), which form the other lineage, are arguably the most successful of vertebrates and certainly the most successful 'fishes'. One group of lobe-fins gave rise to the tetrapods, which have become other most successful group of vertebrates. Strictly speaking, since tetrapods evolved from lobe-fins, all tetrapods –including us— are also lobe-fins.

Hyneria

Hyneria was a prehistoric predatory lobe-finned fish that lived during the Devonian period around 360 million years ago. It was approximately 4 meters in length and weighed as much as two tons. There is evidence from bones that it had very strong fins and maybe could surf onto shore like modern orca.

Dunkleosteus

With an estimated size reaching 10 meters and its powerful crushing jaws, Dunkleosteus was the top predator of its time, the Late Devonian. Dunkleosteus had a worldwide distribution. D. terrelli, the best known species, is known from numerous remains in North America, while other species have been described from Belgium, Poland and Morocco.

Devonian Marine Mural

Pictured: Dunkleosteus Artist: © 2010 by Karen Carr and Karen Carr Studio, Inc.

Sharks, or Chondricthyes, developed during the Devonian also. Sharks are thought to be descendants of the large Placoderms, but they lost the ability to form the bony armor on the outside of the body and were unable to form bones on the inside also. Their body is supported by cartilage. Because of the skeletons of cartilage, very little fossil evidence is available. They did leave behind their teeth.

Stethacanthus is an extinct genus of shark which lived in the Late Devonian and Early Carboniferous epochs, around 360 million years ago. Fossils have been found in Europe and North America. Stethacanthus was around 2.3 ft long, and in many respects, had a typical shark-like appearance. However, it is best known for its unusually shaped dorsal fin, which resembled an anvil or ironing board. Small spikes (enlarged versions of the dermal denticles commonly covering shark skin) covered this crest, and the shark's head as well. The crest may have played a role in mating rituals, or used to frighten potential predators.

Devonian Fish

In the Early Devonian (416-397 Mya), the sarcopterygians split into two main lineages — the coelacanths and the rhipidistians. The Placodermi were a class of armored prehistoric fish, known from fossils, which lived from the late Silurian to the end of the Devonian Period. Their head and thorax were covered by articulated armored plates and the rest of the body was scaled or naked, depending on the species. Placoderms were among the first jawed fish. The first identifiable Placoderms (armored fish) evolved in the late Silurian; they began a dramatic decline during the Late Devonian extinctions, and the class was entirely extinct by the end of the Devonian.

Guiyu

Guiyu is an extinct genus of bony fish, and is the earliest known one. Fossil range: Late Silurian. It is the earliest known representative of a very large vertebrate group, the 'bony fishes' or Osteichthyes, the class of vertebrates that includes everything from humans to halibut. There are more than 60,000 living species of Osteichthyes today, including almost all the fish that we eat (except sharks) and all land vertebrates. The find may lead the focus of research on the early evolution of vertebrates to a earlier period in geologic time (the Silurian period rather than the former Devonian period ).

Paleozoic Marine Life

The Paleozoic or Palaeozoic Era ('ancient life') is the earliest of three geologic eras of the Phanerozoic Eon. The Paleozoic spanned from roughly 542 to 251 million years ago, and is subdivided into six geologic periods; from oldest to youngest they are: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. Fish populations exploded in the Devonian. During the late Paleozoic, great forests of primitive plants thrived on land forming the great coal beds of Europe and eastern North America. By the end of the era, the first large, sophisticated reptiles and the first modern plants (conifers) had developed. The Paleozoic Era ended with the largest mass extinction in Earth's history, the Permian-Triassic Extinction Event.

Cephalaspis

Like its immediate osteostracan ancestors, Cephalaspis was heavily armored, presumedly to defend against predatory placoderms and eurypterids, as well as to serve as a source of calcium for metabolic functions in calcium-poor freshwater environments. It had sensory patches along the rim and center of its head shield, which were used to sense for worms and other burrowing organisms in the mud. The documentary Walking With Monsters suggested that Cephalaspis, or one of its relatives was an ancestor to jawed fish and other gnathostomes (ultimately to Hominim) however, Cephalaspis belongs to the Osteostraci, a group which is widely believed to be the sister group to all jawed vertebrates. So whilst Cephalaspis was not a direct ancestor of the jawed vertebrates, Cephalapsis nevertheless shared a common ancestor.

Early Plants on Land

The first unambiguous record of land plants is from the Silurian period. They were mostly small, primitive forms, dependent on the proximity of water, and with the most rudimentary stem and leaf structure. True vascular plants evolved and began to diversify during the Latest Silurian and Early Devonian. The earliest evidence of land plants and fungi appears in the fossil record around 480 million years ago. Before that, the Earth's landscape was believed to consist of barren rocks, home to bacteria and possibly some algae. But Plants colonized land hundreds of millions of years earlier than the fossil record suggests, according to scientists in North America. Genetic evidence gleaned from living species puts the date when land plants first evolved at about 700 million years ago.

Early Devonian Marine Biota

The Late Devonian extinction only impacted marine life. Brachiopods, trilobites, and other families were heavily affected. This was one of five major extinction events in the history of the Earth's biota. Reef-building organisms were almost completely wiped out, so that coral reefs returned only with the development of modern corals in the Mesozoic. The causes of these extinctions are unclear. The leading theories suggest that changes in sea level and ocean anoxia, possibly triggered by global cooling or oceanic volcanism, were most likely responsible, although the impact of an extraterrestrial body such as a comet has also been considered.

Devonian Marinescape

Devonian life in the shallow inland seas continued much as it had in the Silurian, with extensive coral reefs and ocean plants.

Earliest Fish

Earliest Fish clockwise: astrapis - Myllokunmingia - Haikouichthys - flussneunauge - pikia - euconodonts Myllokunmingia is a chordate from the Lower Cambrian. http://en.wikipedia.org/wiki/Myllokunmingia Haikouichthys is an extinct genus of craniate (creatures with backbones and distinct heads) believed to have lived c. 530 million years ago, during the Cambrian explosion. Haikouichthys was featured in the BBC documentary Walking with Monsters as the ancestor to all vertebrates.

Branchiostoma lanceolatum

(Lancelet or Amphioxes)The lancelets, also called amphioxus, (along with the larvae of Tunicates and Seasquirts) are the extant basal representatives of the phylum Chordata, subphylum Cephalochordata. They are usually found buried in sand in shallow parts of temperate or tropical seas. In Asia, they are harvested commercially as food for humans and domesticated animals. They are an important object of study in zoology as they have notochords and provide indications about the origins of the vertebrates.

The Ordovician Extinction

The Ordovician–Silurian extinction event or quite commonly the Ordovician extinction, was the third-largest of the five major extinction events in Earth's history in terms of percentage of genera that went extinct and second largest overall in the overall loss of life. Between about 450 Ma to 440 Ma, two bursts of extinction, separated by one million years, appear to have happened. This was the second biggest extinction of marine life, ranking only below the Permian extinction. At the time, all known life was confined to the seas and oceans. More than 60 per cent of marine invertebrates died including two-thirds of all brachiopod and bryozoan families.

Ordovician life included a larger diversity of predators, including straight-shelled 'nautiloid-like' or 'squid-like' creatures.

Ordovician marine environment

Endocerida comprises a diverse group of cephalopods that lived from the Early Ordovician possibly to the Late Silurian. Their shells varied in form. Some were straight others curved. Some long-shelled forms like Endoceras attained lengths as much as 12 ft. The related Cameroceras is reported to have reached lengths approaching (30 feet), but these claims are not unproblematic. In any event they were the largest animal that, up until that time, had ever lived.

Cambrian Brachiopods

Over 30,000 species of brachiopods are believed to have evolved over the years. Some extant brachiopods like the lampshells produce freeswimming larvae so considering that ontogeny may recapitulate phylogeny it is not surprising that these Cambrian brachiopods are represented as swimming freely.

Asteroid Impact Extinction Events

Since life began on Earth, asteroid impacts were probably implicated in many of possibly dozens of major mass extinction events. Most likely occurred in the Archean and Proterozoic Eons, but before the Phanerozoic there were no animals with hard body parts to leave a significant fossil record. The most recent, the Cretaceous–Tertiary extinction event with strong evidence that it resulted from asteroid impact, occurred 65 mya, that marks the extinction of nearly all dinosaur species. In the past 540 million years there have been five major events when over 50% of animal species died with the Permian-Triassic being the most devastating.

Haikouichthys

Haikouichthys is an extinct genus of craniate (creatures with backbones and distinct heads) believed to have lived c. 530 million years ago, during the Cambrian explosion. Haikouichthys had a defined skull and other characteristics that have led paleontologists to label it a true craniate, and even to be popularly characterized as one of the earliest fish, but it does not possess sufficient features to be included uncontroversially even in the stem group.

Anomalocaris

Anomalocaris ('abnormal shrimp') is an extinct genus of anomalocaridid, which are, in turn, thought to be closely related to the arthropods. The first fossils of Anomalocaris were discovered in the Ogygopsis Shale by Joseph Frederick Whiteaves, with more examples found by Charles Doolittle Walcott in the famed Burgess Shale. Originally several fossilized parts discovered separately (the mouth, feeding appendages and tail) were thought to be three separate creatures. it took several more years for researchers to realize that the continuously juxtaposed Peytoia, Laggania and feeding appendage actually represented a single, enormous creature. For the time in which it lived, Anomalocaris was a truly gigantic creature, reaching lengths of up to one meter.

Pikia

Pikaia gracilens is an extinct animal known from the Middle Cambrian Burgess Shale of British Columbia. 16 specimens of Pikaia are known from the Greater Phyllopod bed, where they comprise 0.03% of the community. It resembles a living chordate commonly known as the lancelet and perhaps swam much like an eel. During his re-examination of the Burgess Shale fauna in 1979, paleontologist Simon Conway Morris placed P. gracilens in the chordates, making it perhaps the oldest known ancestor of modern vertebrates, because it seemed to have a very primitive, proto-notochord. The status of Pikaia as a chordate is not universally accepted; its preservational mode suggests that it had cuticle, which is uncharacteristic of the vertebrates.

Smithsonian Burgess Shale Community

Pictured: Pikia, Marrella, Anomalocaris, Yohoia, Opabinia Smithsonian National Museum of Natural History

Diania cactiformis

Diania is an extinct genus of animal found in the Lower Cambrian Maotianshan shale of China, from around 500 million years ago, represented by a single species about 2.4 in long. At the front end of its thin body is a proboscis, presumably used in feeding. These animals have ten pairs of legs, and compared to the body these are quite robust and spiny. Because of this spiny appearance in the rocks the animal became known informally as the 'walking cactus'. The most important aspect is that legs appear to be jointed, with a hard exoskeleton divided into ring-like articles. The creature belongs to a group known as the armoured lobopodians and has a simple worm-like body with robust, spiny, and apparently jointed legs that sheds light on how jointed legs of insects, spiders and crustaceans might have originated and thus be very close to the origins of the most diverse group of animals on the planet.

Cambrian Sea

The Cambrian is the first geological period of the Paleozoic Era, lasting from 542 Mya to 488 Mya; it is succeeded by the Ordovician. Its subdivisions, and indeed its base, are somewhat in flux. The Cambrian is unique in its unusually high proportion of lagerstätten. These are sites of exceptional preservation, where 'soft' parts of organisms are preserved as well as their more resistant shells. This means that our understanding of the Cambrian biota surpasses that of later periods.

Silurian Marinescape

Pictured: Eurypterids, chain coral, fish

Burgess Shale Cambrian Community

The Burgess Shale Formation — located in the Canadian Rockies of British Columbia — is one of the world's most celebrated fossil fields, and the best of its kind. It is famous for the exceptional preservation of the soft parts of its fossils. It is 505 million years old (Middle Cambrian), one of the earliest soft-parts fossil beds. Free-swimming organisms are relatively rare, with the majority of organisms being bottom dwelling — either moving about or permanently attached to the sea floor. About two-thirds of the Burgess Shale organisms lived by feeding on the organic content in the muddy sea floor, while almost a third filtered out fine particles from the water column. Under 10% of organisms were predators or scavengers, although since these organisms were larger, the biomass was split equally between each of the filter feeding, deposit feeding, predatory and scavenging organisms.

Ottoia

Ottoia, showing muscle bands and gut. Ottoia is a priapulid predatory worm found commonly in the Burgess Shale of the Cambrian period. The Cambrian is the first geological period of the Paleozoic Era, lasting from 542 to 488.3 Mya. It is succeeded by the Ordovician.

Marella splendens

The 'Lace crab' reconstruction is from fossil specimens recovered from Cambrian deposits laid down in the Burgess Shale 543-490 million years ago. The name arthropod comes from Greek arthron ('joint') and pod ('foot').

Opabinia ediacara

Ediacaran Fauna - The Vendian Period

650 to 543 Mya the latest part of the Proterozoic. The main and most conspicuous elements of the Vendian biota belong to the Ediacara fauna named for a locality in Australia where fossils were identified. This is the time when the earliest-known animals (metazoan) evolved, and the continents had merged into a single super continent called Rodinia. The fauna is entirely soft-bodied and was probably adapted to relatively low oxygen conditions in a variety of both earlier, deeper and later nearshore marine environments. center: Dickinsonia a metazoan that grew to a length over 1.5 feet - bottom: microdictyon (a bilateral worm)

Edicarian Biota

Edicarian life is believed to have evolved during the 40 million years immediately preceding the start of the Cambrian over 540 Mya. Determining where Ediacaran organisms fit in the tree of life has proven challenging; it is not even established that they were animals, with suggestions that they were lichens (fungus-alga symbionts), algae, protists known as foraminifera, fungi or microbial colonies, to hypothetical intermediates between plants and animals. The morphology and habit of some taxa suggest relationships to Porifera or Cnidaria and other organisms have been thought to possess bilateral symmetry. Most macroscopic fossils are morphologically distinct from later life-forms: they resemble discs, tubes, mud-filled bags or quilted mattresses that do not resemble any living organism.

Ediacaran

The organisms of the Ediacaran Period (formerly Vendian Period) first appeared around 580 million years ago and flourished until the cusp of the Cambrian 542 million years ago when the characteristic communities of fossils vanished. Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular organisms. Most macroscopic fossils are morphologically distinct from later life-forms: they resemble discs, tubes, mud-filled bags or quilted mattresses. Due to the difficulty of deducing evolutionary relationships among these organisms some paleontologists have suggested that these represent completely extinct lineages that do not resemble any living organism so determining where Ediacaran organisms fit in the tree of life has proven impossible.

Impact Event

Lost City

A spectacular tower- a hydrothermal vent - harboring anaerobic deepsea life at the Lost City of - rov lights in background.

Black Smoker

A diverse community of anaerobic benthic marine life feed on the sulfurous/methane gases and mineral precipitates pouring from a hydrothermal vent. A hydrothermal vent is a fissure in a planet's surface from which geothermally heated water issues. Hydrothermal vents are commonly found near volcanically active places, areas where tectonic plates are moving apart, ocean basins, and hotspots. It is suggested that it was in such an environment in early Earth where life first established.

Black Smokers

Some theories indicate that life originated at hydrothermal vents from inorganic precursors. Extant submarine hydrothermal vents create life support for chemosynthetic bacteria that grow into a thick mat which attracts other organisms such as amphipods and copepods which graze upon the bacteria directly. Larger organisms such as snails, shrimp, crabs, tube worms, fish, and octopuses form a food chain of predator and prey relationships above the primary consumers. The main families of organisms found around seafloor vents are annelids, pogonophorans, gastropods, and crustaceans, with large bivalves, vestimentiferan worms, and 'eyeless' shrimp making up the bulk of non-microbial organisms.

Pompeii-Worm This extremophile keeps a cool head even in extreme temperatures. The Pompeii Worm finds a habitat on or near Black Smokers, hydrothermal vents on the sea floor, which give the worm its volcanic name. Nestled within its cozy tube, its body stays at a very toasty 175º F, while its plume-like head protrudes from the tube into water that is a much more temperate 72º F. Weirder still, its fleecy coat is actually a colony of bacteria that lives in a symbiotic relationship with the worm, fed by mucus secretions produced by the worm. Truly an oddity, the Pompeii worm (and its living coat) obviously has a lot to teach us about living in an extreme range of temperatures.

Riftia pachyptila

A ventimiferan tubeworm exists deep in the ocean near hydrothermal vents. It can grow to over 2 meters. It is a worm with no mouth, no guts, and no anus.

Extremophile

Extremophilic microbes can be found thriving in some of the most hostile environments imaginable - swimming in near-boiling water, eating rocks, lounging in subzero temperatures and hanging out where radiation levels rival nuclear reactors. The European Mars Express mission detected hints of methane in Mars atmosphere, and some astrobiologists have speculated that the methane could be a by-product of extremophilic methanogens or some other form of microbial life.

Water Bears

Dr. Daiki Horikawa from NASA Ames Research Center has been examining strange creatures called tardigrades, nicknamed 'water bears', small invertebrate animals that live in terrestrial mosses, soil, or lichens. They also inhabit ocean and polar regions. Recent research has shown that water bears can survive the dangerous conditions of space. Previously, the only organisms that have been exposed to the radiation and vacuum of space and lived to tell the tale are certain types of bacteria and lichen. Tardigrades have the ability to enter a suspended animation-like state when they cannot find enough water. That simple animals like tardigrades also can survive gives more credence to the theory of panspermia, which claims that organisms could move from world to world after traveling though space.

Annelida

Extant representatives of a form our ancestor once may have resembled. The first systematic investigation of an annelid genome has revealed that the genes of the marine worm Platynereis dumerilii are more closely related to those of vertebrates than to those of insects or nematodes. For hundreds of millions of years vertebrates have preserved exon-intron structures descended from their last common ancestor with the annelids.

Platynereis dumerilii

Researchers from the European Molecular Biology Laboratory (EMBL) now reveal that the hypothalamus and its hormones are not purely vertebrate inventions, but have their evolutionary roots in marine, worm-like ancestors.

Vetulicolia An extinct phylum of several Cambrian organisms that lack preserved appendages of any kind. They may represent stem- and crown-group arthropods, stem-group vertebrates, and early deuterostomes.

Bilateria

The Bilateria are all animals having a bilateral symmetry, i.e. they have a front and a back end, as well as an upside and downside. Radially symmetrical animals like jellyfish have a topside and downside, but no front and back. The bilateralians are a major group of animals, including the majority of phyla; the most notable exceptions are the sponges and cnidarians.

Extant Echinoidea (sea urchins, sand dollars)

Echinoderms first appear in the fossil record during the mid-Cambrian. Arkarua, a possible echinoderm, has been described from the Vendian (latest Proterozoic).

Extant Actiniae

Sea anemones are seemingly primitive animals that, along with corals, jellyfish, and hydras, constitute the oldest eumetazoan phylum, the Cnidaria.

Achaeocyatha (calcium sponges)

Sponges, the oldest known living animal group, have no neurons, no synapses, no internal organs and consist of only a limited number of discrete cell types. Sponges are regarded as animals without true tissues and therefore may represent the earliest stage in the evolution of animal multicellularity (Boero et al., 2007).

Tunicate

Chordates (phylum Chordata) are animals which are either vertebrates or one of several closely related invertebrates. They are united by having, for at least some period of their life cycle, a notochord, a hollow dorsal nerve cord, pharyngeal slits, an endostyle, and a post-anal tail. The phylum Chordata consists of three subphyla: Urochordata, represented by tunicates; Cephalochordata, represented by lancelets; and Craniata, which includes Vertebrata.

Hydra

Perhaps the best-known hydrozoan, familiar to most students of introductory biology, is Hydra. Hydrozoan may date back to the Vendian (late Precambrian). Hydra never goes through a medusoid stage and spends its entire life as a polyp. However, Hydra is not typical of the Hydrozoa as a whole. Most hydrozoans alternate between a polyp and a medusa stage — they spend part of their lives as 'jellyfish'.

Scyphozoa

Scyphozoa is a class within the phylum Cnidaria, sometimes referred to as the 'true jellyfish'. Scyphozoans range in geological time from the Ediacaran period through the Recent.

Trichoplax adhaerens

Could slimy, shapeless creatures called placozoans resemble the last common ancestor of all animals? For the last 100 years a primordial sponge was favored to represent the 'urmetazoan' (or 'first animal') a creature that has inspired countless studies and debate. A recent molecular analysis may knock the sponge off its throne as the most primitive living animal in favor or a flat, gnat-sized, amoeba-like blob called Trichoplax adhaerens. Sometime before 600 mya, the first animals evolved from protists - mainly single-celled microorganisms. What happened next is open for debate. Bernd Schierwater posits a new theory of the animal family tree that a hypothetical predecessor of Trichoplax adhaerens called the placula was the first animal, and that diploblasts and the more comples triploblasts evolved separately from it.

Colony of the Archaea Methanosarcina mazei. These primitive archaebacteria have unusual cell walls and membranes and are methane producers. SEM X20,000

Eukaryotic Fossil

The rise of oxygen and the oxidation of deep oceans between 635 and 551 million years ago may have had an impact on the increase and spread of the earliest complex life, including animals. Pulsed oxidation and biological evolution in the Ediacaran Doushantuo Formation. 2008. K. A. McFadden et al. The photo (field of view about 0.15 millimeter in width) is of an exceptionally preserved eukaryotic fossil from the Doushantuo Fm (635–551 million years old) in South China.

Amoebozoan

Vase-shaped microfossils (VSMs) discovered around the world show that amoebozoans have existed since the Neoproterozoic Era- the terminal Era of the formal Proterozoic Eon (or the informal 'Precambrian'). Amoeba is an example of an unicellular animal-like protist Eukarya with pseudopods.

Snowball Earth

Early mass extinctions: Breakup of a single landmass 770 million years ago in the Precambrian Period, leaves small continents scattered near the equator. Global temperatures fall, and large ice packs form in the polar oceans. The white ice reflects more solar energy driving temperatures even lower. This feedback cycle engulfs the planet in ice within a millennium. The oceans ice over to an average depth of more than a kilometer, limited only by heat from the earth's interior. Most microscopic marine organisms die, but a few cling to life around volcanic hot springs. The cold, dry air arrests the growth of land glaciers, creating vast deserts of windblown sand. As carbon dioxide accumulates from volcanoes, the planet warms and sea ice slowly thins. 70 million years later, the same thing happened again.

Earth Deep Freeze

Drs. Paul Hoffman and Daniel Schrag of Harvard propose that roughly 700 million years ago, the Earth's climate cooled and the polar ice caps expanded. As the ice advanced, more and more sunlight was reflected back into space, causing the temperature to drop even further. By the time the ice caps covered roughly half of the globe, the cooling process was rapid and unstoppable. Soon the Earth was completely entombed in ice one kilometer thick. In fact, the geologic record indicates the global climate flip-flopped not just once, but two to five times. But what's most remarkable about the idea is not that the Earth ever froze over, but when. The last thaw occurred about 585 million years ago, just about the same time multicellular animal life proliferated on this planet. The timing of the last worldwide glacial retreat and the Cambrian explosion is simply too much to over look.

Global Vulcanism

The single-celled prokaryotic bacteria that built stromatolites is known from 3.5 billion years ago. It wasn't until around 800 Mya that these cyanobacteria had raised the level of oxygen in the atmosphere to support higher energy eukaryotic life forms that evolved into multi-cellular versions. One theory suggests that oxidizing iron in early Earth's crust was binding so much of the O2 that it delayed this enrichment. Eventually the photosynthesis of so much carbon dioxide from the atmosphere caused the greenhouse protective layer of CO2 to collapse, ushering in a period known as the Sturtian glaciation or 'Snowball Earth' in which the planet froze over completely, subjecting early metazoan to extreme conditions. Around 630 Mya the onset of global vulcanism, re-established the layer of greenhouse gases- the ice melted and the combination of events in the Late Precambrian led to the famously diverse Cambrian taxa around 500 Mya.

Cyanobacteria (formerly called Blue-Green Algae)

The most common cyanobacterial structures in the fossil record include stromatolites and oncolites with evidence in the geologic record indicating that the transforming event of photosynthesis took place early in our planet's history, at least 2450-2320 million years ago (mya), and probably much earlier. Cyanobacteria are primitive algae that are largely responsible for the Earth having an oxygenated atmosphere. Cyanobacteria are not plants and are more similar to bacteria. Unlike plants and animals, cyanobacteria do not have a cell nucleus. Cyanobacteria can be unicellular, colonial, or form filaments and their cells are often much smaller than other algae. Some cyanobacteria produce toxins that damage human liver and nervous systems.

Living Stromatolite

Stromatolites were much more abundant on the planet in Precambrian times. While older, Archean fossil remains are presumed to be colonies of single-celled blue-green bacteria, younger (that is, Proterozoic) fossils may be primordial forms of the eukaryote chlorophytes (that is, green algae). One genus of stromatolite very common in the geologic record is Collenia. The earliest stromatolite of confirmed microbial origin dates to 2.724 billion years ago. A recent discovery provides strong evidence of microbial stromatolites extending as far back as 3.4 billion years ago.

Bacillus anthracis vegetative (Anthrax)

Almost certainly the first living bodies were microscopic in size, being single-celled. Bacteria were the dominant, perhaps the only, major life forms. The current consensus is that Archaebacteria emerged at least 3.5 billion years ago and are the oldest life forms. Most researchers would add the nucleus to the list of 'new' eukaryotic features, but its interesting to note that all RNA world fossils are found in the nucleus. The assumption that the nucleus is recent is based on the argument that evolution drives towards complexity, but we know this isn't always so. It is also a possibility that the nucleus is old, and prokaryotes bacteria have lost it.

Single Celled Life

By the start of the Archean Eon 4 billion ya, the Earth's crust had cooled. The atmosphere was composed of volcanic gases, including nitrogen, hydrogen, carbon, and possibly low levels of oxygen. Water vapor was abundant and the first oceans had formed. A complex set of chemical reactions in these early oceans transformed carbon-containing molecules into simple, single-celled life forms around 3 billion ya- the highest lifeforms for some 2.5 billion years.

Virus Evolution and Origins

Despite recent advances in our understanding of diverse aspects of virus evolution, particularly on the epidemiological scale, revealing the ultimate origins of viruses has proven to be a more intractable problem. Herein, I review some current ideas on the evolutionary origins of viruses and assess how well these theories accord with what we know about the evolution of contemporary viruses. I note the growing evidence for the theory that viruses arose before the last universal cellular ancestor (LUCA). This ancient origin theory is supported by the presence of capsid architectures that are conserved among diverse RNA and DNA viruses and by the strongly inverse relationship between genome size and mutation rate across all replication systems, such that pre-LUCA genomes were probably both small and highly error prone and hence RNA virus-like.

Glycogen Carbohydrate

Scientists have demonstrated that a five-nucleotide-long ribozyme can catalyze a key reaction needed to synthesize proteins, bearing implications for the origin of life on Earth. Their findings present further evidence that the first catalytic macromolecules could have been RNA molecules. Since they are simpler than protein-based enzymes, they “were likely to exist early in the formation of the first life forms, and are capable of catalyzing chemical reactions without proteins being present.

Organic Molecules in Early Universe

This artist's conception symbolically represents complex organic molecules, known as polycyclic aromatic hydrocarbons, seen in the early universe. These large molecules, comprised of carbon and hydrogen, are considered among the building blocks of life. NASA's Spitzer Space Telescope is the first telescope to see polycyclic aromatic hydrocarbons so early -- 10 billion years further back in time than seen previously. Spitzer detected these molecules in galaxies when our universe was one-fourth of its current age of about 14 billion years. These complex molecules are very common on Earth as they form any time carbon-based materials are not burned completely such as sooty exhaust from cars and airplanes. Polycyclic aromatic hydrocarbons are pervasive in galaxies like our own Milky Way, and play a significant role in star and planet formation.

Goldilocks Planet

Gliese 581g is one of six planets in orbit around a dwarf star Gliese 581- about one-third the strength of our sun. It is about three times the mass of Earth, slightly larger in width and much closer to its star — 14 million miles away versus 93 million. It's so close to its version of the sun that it orbits every 37 days. And it doesn't rotate much, so one side is almost always bright, the other dark. Temperatures can be as hot as 160 degrees or as frigid as 25 degrees below zero, but in between — in the land of constant sunrise — it would be 'shirt-sleeve weather'. It's about about 120 trillion miles away, so it would take several generations for a spaceship to get there. In the scheme of the vast universe, this planet is 'like right in our face, right next door to us. It is unknown whether there is water there.

Amino Acids Detected in Comet

NASA has announced it has discovered an amino acid in samples it took from comet Wild 2 with its Stardust probe. Glycine is used by living organisms to make proteins and scientists say its presence backs up the theory that life's ingredients were delivered to Earth by meteorite and comet impacts. It also boosts the chances of life being common throughout the universe. Proteins are made up of chains of amino acids arranged to make everything from your eyes to your hair. One of the most studied rocks on Earth is the Murchison meteorite. It fell in Australia back in 1969 and is jam-packed with organic compounds. One of the most studied rocks on Earth is the Murchison meteorite. It fell in Australia back in 1969 and is jam-packed with organic compounds- building blocks of life that rained down on our planet to give the primordial soup its extra life-creating potential.

Rapid Extinction for Emergent Life

Most geologists agree that plate tectonics began as the Earth's crust cooled and cracked into separate tectonic plates several hundred million years or more after its fiery genesis 4.6 billion years ago. Volcanic eruptions from the heated interior and external heavy bombardment by small bodies may have extinguished emerging life on a rapid timescale. The oldest known fossilized prokaryotes were possibly laid down over 3.5 billion years ago, less than 1 billion years after the formation of the Earth's crust. The prokaryotes are a group of organisms that lack a cell nucleus or any other membrane-bound organelles. They differ from the eukaryotes, which have a cell nucleus. The prokaryotes are divided into two domains: the bacteria and the archaea. Even today, prokaryotes are perhaps the most successful and abundant life forms.

Late Heavy Bombardment Aftereffects

A new study (2014) estimates the thermal effects of a period known as the Late Heavy Bombardment (LHB) on Earth. The LHB is hypothesized to have occurred roughly 3.9 billion years ago during the Hadean eon, and was a time when impacts were especially frequent. Heat generated by the impacts left up to 10 percent of the planet's surface covered with melt sheets more than a kilometer thick. Ejecta and vaporized rock were sprayed into the air and deposited around the globe. Astrobiologists have long wondered if any evidence of LHB impacts could still remain in rocks left over from the Hadean (such as rocks from the Jack Hills in Australia).

Late Heavy Bombardment

The late heavy bombardment of asteroids that clobbered Earth and the rest of the inner solar system for 20 to 100 million years, ending 3.85 billion years ago, is generally regarded as one of the most hostile eras in our planet's history. However new studies are turning this view on its head, hinting that the ancient rain of asteroids may actually have established a more favorable environment for life to take hold. Researchers propose that if early bacteria were living more than 2.5 miles deep, the impacts could have helped life by creating more hot-water filled cracks for microbes to inhabit.

Murchison Meteorite

A rocky meteorite 4.5 billion years old found in Murchison, Australia, in 1969 This is a fragment of the meteorite that gave scientists the first evidence of extraterrestrial organic compounds. Scientists found that it contains sugars, amino acids, and other organic compounds. It is pictured here in a fanciful impression of the asteroid belt- a region of the Solar System located roughly between the orbits of the planets Mars and Jupiter. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets. The asteroid material is so thinly distributed that multiple unmanned spacecraft have traversed it without incident so the illustration which pictures the Murchison meteorite among closely-packed bodies is unrealistic.

Giant Impact Hypothesis

he giant impact hypothesis, sometimes called the Big Splash, or The Theia Impact states that the Moon was formed out of the debris left over from an indirect collision between the Earth and an astronomical body the size of Mars, approximately 4.5 billion years ago, in the Hadean eon; about 20–100 million years after the solar system coalesced. The colliding body is sometimes called Theia, for the mythical Greek Titan who was the mother of Selene, the goddess of the Moon. TGI hypothesis is currently the favoured scientific hypothesis for the formation of the Moon. Supporting evidence includes the Earth's spin and Moon's orbit having similar orientations, Moon samples indicating the surface of the Moon was once molten, the Moon's relatively small iron core, lower density compared to the Earth, evidence of similar collisions in other star systems with debris disks, and that giant collisions are consistent with the leading theories of the formation of the solar system. Finally, the stable isotope ratios of lunar and terrestrial rock are identical, implying a common origin.

Massive Rocky Bodies Collide

This artist's rendering shows what the environment around HD 23514 might look like. Heat radiating from dust around the star indicates that there may have been a recent collision between two large, rocky bodies - similar to the collision that formed the Earth's Moon.

Life on Europa

Europa, one of Jupiter's satellites is another possible candidate within our solar system where conditions may exist that are generally considered to be necessary for life. These include the following: Orbit around a yellow star (like the Sun), a red dwarf, or a stable combination of those stars; Presence of water, carbon and other organic elements (believed to be fairly common.); Orbit within the habitable zone (distance from star where the temperatures allow water to exist as ice, liquid water and vapor); Presence of an active core that causes volcanic and tectonic activity as well as a magnetic field to protect the surface from cosmic and solar radiation; The size and density of the planet have to be such that the planet's gravity can hold an atmosphere, but is not too strong to crush lifeforms.

Andromeda

Andromeda (M31) is the nearest spiral galaxy to our own, the Milky Way. The Andromeda Galaxy is approaching our Sun at about 100 to 140 kilometres per second so the two galaxies are expected to collide in perhaps 4.5 billion years. This suggests that if no other cataclysmic event intervenes- life on Earth may have a chance to evolve over the same span of time since its creation 4.5 billion years ago.

Titan

Titan is the largest moon of Saturn, the only natural satellite known to have a dense atmosphere, and the only object other than Earth for which clear evidence of stable bodies of surface liquid has been found. The moon itself is primarily composed of water ice and rocky material. Much as with Venus prior to the Space Age, the dense, opaque atmosphere prevented understanding of Titan's surface until new information accumulated with the arrival of the Cassin-Huygens mission in 2004, including the discovery of liquid hydrocarbon lakes in the satellite's polar regions. These are the only large, stable bodies of surface liquid known to exist anywhere other than Earth.

Solar Flare

Scientists using NASA's Swift satellite have spotted a stellar flare on a nearby star 11 Pegasi in constellation Pegasus so powerful that, had it been from our sun, it would have triggered a mass extinction on Earth. The flare was perhaps the most energetic magnetic stellar explosion ever detected and is evidence of the hazards in space for prebiotic life forms.

Fledgling Solarsystem

NASA's Spitzer Space Telescope observed a fledgling solar system like the one depicted in this artist's concept, and discovered deep within it enough water vapor to fill the oceans on Earth five times. This water vapor starts out in the form of ice in a cloudy cocoon (not pictured) that surrounds the embryonic star, called NGC 1333-IRAS 4B (buried in center of image). Material from the cocoon, including ice, falls toward the center of the cloud. The ice then smacks down onto a dusty pre-planetary disk circling the stellar embryo (doughnut-shaped cloud) and vaporizes. Eventually, this water might make its way into developing planets.

Deadly Neutron Stars

As on Earth, emergent life everywhere in the universe faces what would appear to be insurmountable odds against survival. Neutron stars that may number in the billions in our Milky Way have extremely energetic and ultrapowerful magnetic fields and occasionally unleash flares that pack more energy in a fraction of a second than the Sun will emit in tens of thousands or even hundreds of thousands of years. The flares are probably ignited when a massive shift in the crust (a starquake) triggers a large-scale untwisting and rearrangement of magnetic-field lines, causing them to snap and release vast amounts of pent-up magnetic energy in the form of gamma rays, X rays, and particles. Such episodes would likely cause mass extinction of any life over vast regions of space.

Astrobiology Science and Technology for Exploring the Planets

(ASTEP) is a NASA initiative of relevant projects for developing technology related to the study of astrobiology and terrestrial extreme environments.

Carina Nebula

Hubble's view of the Carina Nebula shows star birth in a new level of detail. The landscape of the nebula is sculpted by the action of outflowing winds and scorching ultraviolet radiation from the monster stars that inhabit this inferno. In the process, these stars are shredding the surrounding material that is the last vestige of the giant cloud from which the stars were born.

Supermassive Black Hole

Artist's concept illustrates environs of an enormously dense object - an extreme example of similar phenomenon cosmologists believe is buried at the hearts of galaxies. Scientists have found, startlingly, is that at the center of most galaxies—and there are more than 100 billion galaxies in the universe—is a teeming bulge of stars and gas and dust. At the very hub of this chaotic bulge, in virtually every galaxy looked at, including our own Milky Way, is an object so heavy and so compact, with such ferocious gravitational pull, that no matter how you measure it, there is only one possible explanation: It’s a black hole. These holes are immense. The one at the center of the Milky Way is 4.3 million times as heavy as the sun. A neighboring galaxy, Andromeda, houses one with as much mass as 100 million suns. Other galaxies are thought to contain billion-sun black holes, and some even ten-billion-sun supermassive monsters.

Carina Nebula

A ground-based view of the giant star-forming region. The bright star at the center of the image is eta Carinae, one of the most massive and luminous stars known. Credit: N. Smith and NOAO/AURA/NSF Panspermia and Exogenisis Panspermia is the hypothesis that 'seeds' of life exist already all over the Universe, that life on Earth may have originated through these 'seeds', and that they may deliver or have delivered life to other habitable bodies. The related but distinct idea of exogenesis proposes life on Earth was transferred from elsewhere in the Universe but makes no prediction about how widespread it is. Studies of bacteria frozen in Antarctic glaciers have shown that DNA has a half-life of 1.1 million years under such conditions, suggesting that while life may have moved around within the Solar System it is unlikely that it was from an interstellar source although environments in meteors or comets are somewhat shielded from these hazards.

The Light of Cosmic Consciousness Creates and Sustains the Phenomenal Universe

A map of the early universe made 2006, using the Wilkinson Microwave Anisotropy Probe (WMAP). Thanks to advanced astro technology, cosmologists are intruding on mysteries previously confined to the realms of philosophy, metaphysics and religious faith. These audacious seekers seem on the verge of answering fundamental questions about the origins, scale and fate of the observable universe, the nature of its contents, the prevalence of other Earth-like worlds - and the potential for kindred consciousness on some of them. [Unveiling the Universe - Kathy Sawyer, Na Geog Mag, Oct, 1999]

Origin of Life from Early Mars

An alternative hypothesis of panspermia (origin of life in space) proposed to explain the presence of life on Earth so soon after the planet had cooled down, with apparently very little time for prebiotic evolution, is that life formed first on early Mars. Due to its smaller size Mars cooled before Earth (a difference of hundreds of millions of years), allowing prebiotic processes there while Earth was still too hot. Life was then transported to the cooled Earth when crustal material was blasted off Mars by asteroid and comet impacts. Mars continued to cool faster and eventually became hostile to the continued evolution or even existence of life (it lost its atmosphere due to low volcanism); Earth is following the same fate as Mars, but at a slower rate.

Infinite Multiverses

The multiverse (or meta-universe) is the hypothetical set of infinite or finite possible universes (including the Universe we consistently experience) that together comprise everything that exists: the entirety of space, time, matter, and energy as well as the physical laws and constants that describe them. The various universes within the multiverse are sometimes called parallel universes or 'alternate universes'. The structure of the multiverse, the nature of each universe within it and the relationships among the various constituent universes, depend on the specific multiverse hypothesis considered. The multiverse hypothesis is a source of debate within the physics community. Physicists disagree about whether the multiverse exists, and whether the multiverse is a proper subject of scientific inquiry or one whose nature should only be philosophically approached, since it is not falsifiable.

Bubble Universes

In addition to the multiple universes created by infinitely extending space-time, other universes could arise from a theory called 'eternal inflation'. Inflation is the notion that the universe expanded rapidly after the Big Bang, in effect inflating like a balloon. Eternal inflation, first proposed by Tufts University cosmologist Alexander Vilenkin, suggests that some pockets of space stop inflating, while other regions continue to inflate, thus giving rise to many isolated 'bubble universes'. Thus, our own universe, where inflation has ended, allowing stars and galaxies to form, is but a small bubble in a vast sea of space, some of which is still inflating, that contains many other bubbles like ours. And in some of these bubble universes, the laws of physics and fundamental constants might be different than in ours, making some universes strange places indeed. The illustration shows how bubble universes may eventually involve back into the conscious cosmic matrix (Brahman) from which they were created.

A graphical symbolism for reality as revealed in my Nirvikalpa Samadhi

bottom: translocation between two worlds
middle: experiencing duality of all material knowledge
top: brief transformation to non-dual consciousness (Brahman)