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The FIRST HUMAN Being in Ethiopia, "When God Was Called Lucy"

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“Thus it can be stated confidently that the "Lucy" specimen is ca. 3 m.y. old, while some of the other, stratigraphically lower Hadar hominids are at least 3.3 and possibly as much as 3.6 m.y. old. …

“Thus it can be stated confidently that the "Lucy" specimen is ca. 3 m.y. old, while some of the other, stratigraphically lower Hadar hominids are at least 3.3 and possibly as much as 3.6 m.y. old. “
[Source: Ian Tattersall, et al. eds, Encyclopedia of Human Evolution and Prehistory (Chicago: St James Press, 1988), pp. 239-241]
From: http://www.selamta.net/Lucy.htm

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  • 1. RBG Communiversity Page 1 of 15 RBG Communiversity THE FIRST HUMAN being in Ethiopia “Thus it can be stated confidently that the "Lucy" specimen is ca. 3 m.y. old, while some of the other, stratigraphically lower Hadar hominids are at least 3.3 and possibly as much as 3.6 m.y. old.” [Source: Ian Tattersall, et al. eds, Encyclopedia of Human Evolution and Prehistory (Chicago: St James Press, 1988), pp. 239-241] From: http://www.selamta.net/Lucy.htmLucy in Ethiopia at National Museum of Ethiopia THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 2. RBG Communiversity Page 2 of 15 THE FIRST HUMAN being in Ethiopia http://www.selamta.net/Lucy.htm A team led by Drs. Yohannes Haile-Selassie and Bruce Latimer of the Cleveland Museum of Natural History, Cleveland, Ohio, has been conducting a paleoanthropological survey in the Mille-Chifra-Kasa Gita area of the Afar Region. The survey was conducted under a permit from the Authority for Research and Conservation of Cultural Heritage (ARCCH) of the Ministry of Youth, Sports, and Culture and was financially supported by the Leakey Foundation and the Wenner-Gren Foundation of the United States of America. The team located new hominid-bearing localities in the Burtele Kebele of Mille district in Zone One of the Afar Regional State. The survey team has designated 14 new fossil bearing localities. Three of the localities have yielded early hominid remains. Major fossiliferous areas are around the Mille River east of Mille Town. Mille is 520 KM northeast of Addis Ababa, and the new site is approximately 60 kilometers north of the famous Lucy site. Several additional areas have been documented as fossiliferous although localities were not designated and fossils were not collected. THE FOSSILS The survey team collected a number of fossils that were exposed on the grounds surface. In their exposed position, these specimens could be subjected to erosional forces and had to be collected before they were seriously damaged or destroyed. A total of 12 early hominid fossil specimens were discovered, including parts of one individuals skeleton. Portions recovered thus far include a complete tibia, parts of a femur, ribs, vertebrae, clavicle, pelvis, and a complete scapula of an adult whose sex and stature are yet to be determined, although it is already clear that the individual was larger than Lucy. In addition to this discovery, skeletal parts of other individuals were found in different localities in the area. These discoveries include isolated teeth, and elements from below the neck (arm bones, leg bones, phalanges). The non-hominid fossil assemblage includes animals such as monkeys, horses, large and small carnivores, a variety of antelopes multiple species of pigs, giraffes, rhinoceros, elephants, and deinotheres. Among small mammals, porcupines, cane rats, and other species of rats were discovered. The faunal assemblage also includes crocodiles, fish, and hippopotamus. GEOLOGY AND DATING Exposed sediments in the new fossiliferous area are mostly silty sand and silty clay horizons interbedded with a number of volcanic tuffs and basaltic flows suitable for dating. The total THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 3. RBG Communiversity Page 3 of 15 section in the area is estimated to be about 50 meters thick. Geochronologist Dr. Alan Deino has collected 16 rock samples and the most critical samples above and below the fossiliferous horizon will be dated soon at the Berkeley Geochronology Center in Berkeley, California. The estimated age of the site, based on preliminary field analysis of the associated animal fossils, is roughly 3.8 to 4 million years. However, confirmation has to await radiometric dating of the rock samples. SIGNIFICANCE Based on the associated animal remains, the team believes that the hominid fossils are likely between 3.8 to 4 million years old. This will place the new fossils in time between the earlier 4.4 million year old Ardipithecus ramidus partial skeleton and the younger 3.2 million year old "Lucy" partial skeleton of A. afarensis. The team hopes that the new discoveries will allow scientists to connect the dots -- furthering our knowledge of this important time period in human evolution. Numerous highly important scientific issues will be tackled by the researchers as work continues. However, it is already clear that planned scientific studies of this once in a lifetime discovery will tell us much about how our four-million-year-old ancestors walked, how tall they were, and what they looked like. Haile-Selassie says that it is too early to tell what species is represented by these hominids. This is because the remains are embedded in adhering silt and stone, which now must be removed under a microscope. Comparative studies are then planned, and will be conducted as excavation proceeds. The associated plant and animal fossils and embedding sediments will also be subjected to study by specialists in order to further refine the age and environmental conditions. FUTURE PROSPECTS The team emphasizes that this discovery and its announcement represent the opening of a new door on a poorly known time period. Years of research lie ahead. The new fossiliferous areas are very promising. There is a high chance of recovering more fossil hominids. These hominids will be important in terms of understanding the early phases of human evolution before Lucy. With permit from the Authority for Research and Conservation of Cultural Heritage (ARCCH), the team will continue the search and collection of additional fossil hominids and also excavate next year in an attempt to find the rest of the bones of this skeleton. Source: Cleveland Museum of Natural History THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 4. RBG Communiversity Page 4 of 15 Africa is the cradle of human race. Anthropologists have unearthed the oldest human skeletons in East Africa in places such as Hadar, Olduvai, Laetoli. One of the best preserved human remnants is a female skeleton found at Hadar in Ethiopia. Anthropologists assembled about 40% of the young girl that was given the nick name "Lucy". Lucy was dated between 3.8 and 3 million years ago and belongs to the Australopethicus category. HADAR Hadars paleontological and anthropological significance was discovered in 1968 by M. Taieb, a French geologist. Taieb organized a geological and paleontological survey of the area in 1971, in which he was joined by D.C. Johanson, Y. Coppens, and J. Kalb. These workers formed the International Afar Research Expedition (INRE). They chose Hadar from the many other available sites to begin intensive investigation mainly because of its excellent preservation of faunal remains. THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 5. RBG Communiversity Page 5 of 15 During the initial field season in 1973 the first early hominid fossils were recovered from Hadar, a knee joint and a partial temporal. Nearly 6,000 fossils of mammals, a total of 87 species, were recovered in 1973 and in subsequent seasons. In the fall of 1974 a larger team returned to continue the search and soon made a discovery of hominid teeth. At the end of November D.C. Johanson discovered at locality 288 the partial skeleton of a tiny female hominid, which was nicknamed "Lucy." The 1975 field season brought even more hominid remains, this time at Locality 333. This locality has been interpreted as evidence for the catastrophic death of a group of hominids. The 333 site yielded, by the close of excavations during the 1976-1977 field season, hundreds of hominid fossil fragments derived from at least 13 individuals representing all ages. All of the Hadar fossils were returned after study to the National Museum of Ethiopia in Addis Ababa, where they are permanently housed. The Hadar Formation consists of at least 280 m. of sediment. Over 100 stratigraphic sections have been studied thus far, and it has been possible to subdivide the sedimentary sequence into four stratigraphic members. Radiometric dating has dated the top of the Hadar units at ca. 2.9 million years (m.y.) ago. Dating for the lower units has been more controversial, with estimates 3.6 and 3.3 m.y. ago. Thus it can be stated confidently that the "Lucy" specimen is ca. 3 m.y. old, while some of the other, stratigraphically lower Hadar hominids are at least 3.3 and possibly as much as 3.6 m.y. old. [Source: Ian Tattersall, et al. eds, Encyclopedia of Human Evolution and Prehistory (Chicago: St James Press, 1988), pp. 239-241] THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 6. RBG Communiversity Page 6 of 15 STONE-TOOL MAKING The first humans used sharp stones as tools. "The emergence of a flaked-stone technology during the course of hominid evolution marks a radical behavioral departure from the rest of the animal world and constitutes the first definitive evidence in the prehistoric record of a simple cultural tradition, or one based upon learning. Although other animals Archaeological evidence shows a geometric increase in the sophistication and complexity of hominid stone technology over time since its earliest beginnings 3-2 m.y. ago. Stone is the principal material found in nature that is both very hard and able to produce superb working edges when fractured A wide range of tasks can be performed such as meat cutting and bone breaking". [quoted from Tattersall et al.eds, op.cit., p. 542]. THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 7. RBG Communiversity Page 7 of 15 Human Fossil Adds Fuel to Evolution Debate Hillary Mayell for National Geographic News March 25, 2002 A one-million-year-old partial skull found in Ethiopia has added new fuel to the human origins debate among paleoanthropologists. Ancient Controversy Do hominid fossils from one The skull cap and several other bones from seven individuals—all to two million years ago Homo erectus— were found in a one-million-year-old layer of represent a single species or sediments known as the Dakanihylo Member. numerous branches on the family tree, some of which died out? A one-million- year-old skull cap from Ethiopia rekindles the debate on this issue (above is a reconstruction of a Homo erectus skull). Photograph by Bettmann/CORBIS Reporting in the March 21 issue of the journal Nature, an international team of researchers says the skull provides yet another piece of evidence that a single human ancestor, Homo erectus, ranged across Europe, Asia, and Africa as long ago as 1.8 million years. For the last two decades, the question of whether fossils discovered from between two million and one million years ago represent one species or numerous branches on the family tree, some of which died out, has been a hot button of debate. Tim White, a paleoanthropologist at the University of California, Berkeley and co-author of the study in Nature, believes the partial skull found in Ethiopia resolves that question. "The matter of early hominid distribution and species count is solved—one [species] at a million [years], from Spain to China to Java to Africa," he said. The skull, he said, represents an evolutionary intermediate step linking older, more primitive forms of the species with younger, more human-like forms. Other experts, however, disagree with that conclusion, and the issue remains controversial. Piecing Together Fossil Evidence The partial skull generating all the excitement was found near the village of Bouri in Ethiopia in THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 8. RBG Communiversity Page 8 of 15 what is called the Middle Awash study area. Based on fossils discovered in earlier digs, hominids appear to have lived in the area for nearly six million years. Proponents of the "bushy tree"/multiple-species view argue that African fossils dating to about two million years ago belong to Homo ergaster. Homo erectus, the thinking goes, split off about 1.6 million years ago, and existed only in Asia. The Asian branch was an evolutionary dead end, and the species Homo erectus died off. Under this scenario, modern humans evolved from the original African branch of Homo ergaster. The caves and volcanic soil of Africa are extremely conducive to fossil preservation, and scientists have been able to accurately date African fossils. Fossils found in Eurasia and Asia, however, are more difficult to date and until recently were thought to be much younger than those found in Africa. "Java man" of Indonesia, for instance, was originally placed in the 500,000-year-old range. The nearly one-million-year difference between African and Asian fossils, along with the more primitive features of the early African fossils, contributed to the idea that Homo ergaster and Homo erectus were two species. New technology has allowed for more precise dating of fossils, and recent reassessments put the age of Java man at about 1.5 million years old, contemporaneous with other fossil finds in Africa. The age of fossils found in China has similarly been revised upward. In addition, the researchers found that even taking precise measurements, it was impossible to differentiate between the skulls from Asia, Africa, and Eurasia. The Daka fossils show that as of one million years ago, Homo erectus was probably a single species with gene flow across its known range from Java to Italy to Ethiopia, concluded Henry Gilbert, one of the studys co-authors and a biologist at the University of California, Berkeley. "Lumpers" and "Splitters" The underlying definition of a species is a group of organisms with common attributes, capable of interbreeding. The question is, how different is acceptable? Paleoanthropologists generally fall into one of two categories based on their views of how much variation can exist within species. "Lumpers," such as White and his team, believe there can be a wide range of variation within a species. "Splitters"—the "bushy tree folk," in Whites term— regard the amount of variation seen in the known fossils as indicative of different species. Susan Anton, a paleoanthropologist at Rutgers University, said human origins research is complicated because scientists look at fossils across large geographic ranges and spans of time, and try to reach conclusions based on morphological evidence from a small number of fossils. The situation is comparable to a researcher, one million years from now, looking at a few fossil THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 9. RBG Communiversity Page 9 of 15 remains of an African pygmy and an NBA basketball player. Both are members of the same species, but their features represent a lot of variation within the species. Without genetic or other supporting evidence, its easy to see how questions could arise among anthropologists of the future. Anton takes a middle-of-the-road position on the single-species versus multiple-species debate, saying shes willing to consider "one species with some serious morphs." Susan Anton, a paleoanthropologist at Rutgers University, said the Ethiopian skull is "a great specimen and shows some really neat things," but she is not convinced it bears out Whites claim that the fossil points to a single ancestor one million to two million years ago. Early African fossils, she explained, have morphological characteristics that are very different from those of island Southeast Asia. "The Daka fossil still shows very African features," she said. "I was expecting the specimen to show more of a mix of Asian and African morphology." Fossils From Ethiopia May Be Earliest Human Ancestor David Perlman San Francisco Chronicle July 12, 2001 A team of scientists led by an anthropologist at the University of California-Berkeley has discovered the fossilized remains of what they believe is humanitys earliest known ancestor, a creature that Discovery Site in Ethiopia walked the wooded highlands of East Africa nearly 6 million years ago. The dry washes of the Middle Awash River Valley The discovery, which occurred in the Middle Awash River Valley in Ethiopia are home to a of Ethiopia, is already challenging some existing theories about the recent discovery of what is ancestral lineage of humans. It is also changing scientific views believed to be the fossilized about the nature of the environment that fostered the evolution of remains of humanitys pre-humans as they moved from verdant forests to open grasslands. earliest known ancestor. The team reporting the discovery in the July 12 issue of the journal Copyright 2001 National Nature was led by two Ethiopian scholars: Yohannes Haile- Geographic Society Selassie, an anthropologist still working on his doctorate at the University of California at Berkeley, and Giday WoldeGabriel, a geologist now at UCs Los Alamos National Laboratory in New Mexico. The fossils were gathered during four years of demanding expeditions to a harsh and hostile Ethiopian scrubland where lions and cheetahs hunt at night and few people roam the semi-desert wilderness by day. THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 10. RBG Communiversity Page 10 of 15 The remains include a jawbone with teeth, hand bones and foot bones, fragments of arms, and a piece of collarbone. But most important, the bones also included a single toe bone. Its form provides strong evidence that the pre-human creatures walked upright, the scientists said. The toe bone is a crucial clue to the earliest days of human evolution as it developed soon after the ancestral lines of apes and humans split apart, perhaps 6 million to 8 million years ago. Lingering Questions The fossils in Ethiopia were dated by Paul R. Renne of the Berkeley Geochronology Center. Renne is a co-author of WoldeGabriels report in Nature. Another co-author is Tim D. White, a paleoanthropologist at UC-Berkeley who in 1994 discovered a pre-human fossil, named Ardipithecus ramidus, that was then the oldest known, at 4.4 million years. The latest fossils from Ethiopia vary in age from about 5.2 million to 5.8 million years old, according to Renne. Haile-Selassie has tentatively named the fossils Ardipithecus ramidus kadabba, a subspecies of Whites A. ramidus. In January, a French team headed by Brigitte Senut and Martin Pickford found fossils in Kenya that they dated about 5.8 million years old, from a creature they nicknamed "Millennium Man." Pickford said the newly discovered fossils in Ethiopia are "virtual contemporaries." Its not yet clear where the fossils of Haile-Selassie and WoldeGabriel belong on the family tree. The world of paleoanthropology is highly contentious, and scientists have been trying for many decades to sort out the murky ancestry of todays human race by comparing thousands of fossil bones and skulls. But no evidence is certain and no lineages are clear. Anthropologists call all the species and sub-species of our ancient ancestors hominids, to distinguish them from the ape lineage, which includes chimpanzees. The two branches—apes and hominids—are believed to have separated and evolved from one common ancestor between 6 million and 8 million years ago. In a telephone interview from Addis Ababa, where he is analyzing the fossils, Haile-Selassie said he is being extremely conservative, and the fragments he and Wolde Gabriel plucked from the sun-baked ground may represent an entirely new species of pre-human creature. "It could be the earliest hominid, or it could be a common ancestor, or it gave rise only to the chimpanzee lineage, or it went extinct around 6 million years ago without giving rise to any species," he said. Climate Factor THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 11. RBG Communiversity Page 11 of 15 A major mystery in the story of human evolution is how climate affected the environment where creatures that regularly walked upright—the hominids—first emerged. Now, both sets of recent finds—in Ethiopia and Kenya—could help resolve the puzzle. One widely accepted theory holds that after the ape and hominid lineages split, the earliest human ancestors were forced into the expanding tropical grasslands of the African savanna after the continents thick forests dwindled as a result of climate change. But geochemical analysis of the ancient sedimentary soils where Haile-Selassies Ardipithecus creatures lived shows that the region between 5 million and 6 million years ago was well forested, well watered, and rich in woody plants, according to anthropologist Stanley Ambrose of the University of Illinois, who is also a chemist and a co-author of WoldeGabriels report in Nature. The clear inference, according to Haile-Selassie and WoldeGabriel, is that those early human ancestors of the Miocene epoch were already thriving in the forests of a land that was then being shattered by volcanic eruptions, and millions of years later was to become the stony scrubland it is today. THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 12. RBG Communiversity Page 12 of 15 Oldest Human Fossils Identified Hillary Mayell for National Geographic News February 16, 2005 Human fossils found 38 years ago in Africa are 65,000 years older than previously thought, a new study says—pushing the dawn of "modern" humans back 35,000 years. New dating techniques indicate that the fossils are 195,000 years old. The two skulls and some bones were first uncovered on opposite sides of Ethiopias Omo River in 1967 by a team led by Richard Leakey. The fossils, dubbed Omo I and Omo II, were dated at the time as being about 130,000 years old. But even then the researchers themselves questioned the accuracy of the dating technique. The new findings, published in the February 17 issue of the journal Nature, establish Omo I and II as the oldest known fossils of modern humans. The prior record holders were fossils from Herto, Ethiopia, which dated the emergence of modern humans in Africa to about 160,000 years ago. "The new dating confirms the place of the Omo fossils as landmark finds in unraveling our origins," said Chris Stringer, director of the Human Origins Group at the Natural History Museum in London. The 195,000-year-old date coincides with findings from genetic studies on modern human populations. Such studies can be extrapolated to determine when the earliest modern humans lived. The findings also add credibility to the widely accepted "Out of Africa" theory of human origins which holds that modern humans (later versions of Homo sapiens) first appeared in Africa and then spread out to colonize the rest of the world. The new date also widens the gap between when anatomically modern humans emerged and when "cultural" traits—such as the creation of art and music, religious practices, and sophisticated tool-making techniques—seem to have appeared. Evidence of culture is not extensively documented in the archaeological record until around 50,000 years ago. THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 13. RBG Communiversity Page 13 of 15 The wider gap could add fuel to a long-term debate swirling around when modern human behavior, as opposed to modern human anatomy, emerged. "Those who believe that there is widely scattered evidence of modern behavior going back 200,000 years in Africa will be delighted that modern human anatomy also goes back that far," said John Fleagle, a physical anthropologist at Stony Brook University in New York and one of the co-authors of the study. "[Scientists] who believe that modern human behavior only appeared abruptly about 50,000 years ago will see [the new date as] further expanding the distinction and the temporal gap between modern anatomy and modern behavior." Dating Through Geology Somewhat surprisingly, the first thing the scientific team had to do to come up with the new dates was to relocate the precise location where the fossil remains had been excavated in 1967. They were able to do this using National Geographic Society video footage taken during the first excavation. They also used photographs taken by Karl Butzer, a geologist currently at the University of Texas, who did the original geological studies of the site. Also helpful were hand-drawn maps from the late Paul Abell, another member of the 1967 team. "So we know where Omo I and Omo II are now, and theyre now documented by GPS, so they wont get lost again. But we didnt have GPS 40 years ago," said Frank Brown, a geologist at the University of Utah and a co-author of the study. The remains of Omo I and Omo II were buried in the lowest sediment layer, called Member 1, of the 330-foot-thick (100-meter-thick) Kibish rock formation near the Omo River. In addition to GPS, more advanced dating techniques have also been developed. The researchers sampled the volcanic ash on both sides of the river that lay above where the fossils were found. The ash was the same on both sides. "Then we had to find something to date, and what that takes is a lot of walking," Brown said. "Most of the ashes are very fine grained, they dont have pumice [fragments] in them, so you go along and you go along, and eventually you find a place where there are pumices." The presence of feldspar crystals from a volcanic eruption inside pumice fragments is an indication that the crystals have not been contaminated. Such unadulterated crystals can be dated using a technique called potassium-argon dating. "By dating the crystals held in the pumice, you can say with a high level of confidence that everything in that member [group of sediment layers] is nearly the same date," Brown said. "We used a dating technique called 40AR/39AR, which is a variant of potassium-argon THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 14. RBG Communiversity Page 14 of 15 dating." In the same Member 1 sediment layers, the team found additional Omo I bones, animal fossils, and stone tools. The work was funded by the National Geographic Society, the National Science Foundation, the L.S.B. Leakey Foundation, and the Australian National University. Widening the Gap Although both Omo I and Omo II were classified as Homo sapiens in 1967, the Omo II remains were considered much more primitive. Finding that the two individuals lived at around the same time in the same location suggests that, when modern humans first appeared, there were other, less modern populations also on the scene. The finding may add some new perspective to how we think about how and when "modern" human anatomy evolved. "I have previously regarded Omo II as an archaic or primitive H. sapiens and Omo I as a modern H. sapiens, which would make them the same species," Stringer said. "If Omo I and II do belong together, the variation in the population is greater than I expected, but given what we see in larger fossil samples from other regions, we may need to accept that African populations showed large [physical-form] variation at this time." Everyone agrees that the Omo II cranium is more primitive than the Omo I skull in many features, Fleagle said. "Some see the two as part of a continuum, others see them as very distinct types of hominid," he said. "Whether Omo II gets put in Homo sapiens depends upon where one draws the boundary between H. sapiens and whatever species comes before—H. ergaster, H. erectus, H. heidelbergensis. "Regardless of how Omo II is classified, " he continued, "I dont consider it surprising to find two different morphologies existing at the same time. We know that Homo sapiens and Neandertals existed in Europe at the same time and that in the early Pleistocene [epoch] there was diversity of early hominid morphologies [or body forms]. Indeed, virtually every site that has early modern humans ... seems to show a diversity of morphologies with some more modern and some less so." Exactly when modern behavior, as opposed to modern anatomy, emerged—indeed even how to define modern behavior—is another area in which the Omo fossils might contribute some insight. Common elements used to define modern behavior include planning ahead; innovating technologically; establishing social and trade networks; adapting to changing THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
  • 15. RBG Communiversity Page 15 of 15 conditions and environments; and exhibiting symbolic behavior like cave painting, beadmaking (used to show status or group identity), or burying the dead. The crux of the argument comes down to whether these abilities resulted from a sudden biological and genetic revolution or from a more gradual evolution of abilities that culminated around 50,000 years ago. "I think we are still determining when "modern" behavior started to evolve, and my guess is that it too will have deeper roots in Africa," Stringer said. "There is growing evidence that elements of modern behavior were there a hundred thousand years ago, and I think the gap or mismatch between the emergence of modern anatomy and modern behavior may well be much less significant than currently believed." Spencer Wells is a geneticist and an anthropologist and a National Geographic Emerging Explorer. From an analysis of DNA of thousands of men around the world, Wells says he has discovered that all humans alive today can be traced back to a small tribe of hunter-gatherers who lived in Africa 60,000 years ago. "Many anthropologists, myself included, believe that what makes us truly human is our modern behavior, enabled by a modern brain," Wells said. "Modern behavior starts to show up sporadically around 70,000 to 80,000 years ago but doesnt really take off until around 50,000 years ago—the "Great Leap Forward" and dawn of the Upper Paleolithic [early Stone Age]." The human population appears to have crashed to around 2,000 individuals around 70,000 years ago, at the same time they were headed into the worst part of the last ice age. The crash was possibly brought on by a massive volcanic eruption, Wells said. "The hypothesis is that the survivors of this near-extinction event had to be smarter in order to survive, and this allowed them to settle the rest of the world outside of Africa. So, human- ness may not been widespread until around 50,000 to 60,000 years ago, and this could be seen as the real origin of our species." THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”