The FIRST HUMAN Being in Ethiopia, "When God Was Called Lucy"
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Transcript of The FIRST HUMAN Being in Ethiopia, "When God Was Called Lucy"
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THE FIRST HUMAN being in Ethiopia “When God Was Called Lucy”
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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.htm
Lucy in Ethiopia at National Museum of Ethiopia
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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 ground's 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 individual's 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
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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
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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
Hadar's 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.
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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]
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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].
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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.
The skull cap and several other bones from seven individuals—all
Homo erectus— were found in a one-million-year-old layer of
sediments known as the Dakanihylo Member.
Ancient Controversy
Do hominid fossils from one
to two million years ago
represent a single species or
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
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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 study's 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 White's 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
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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, it's 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 she's 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 White's 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 humanity's earliest known ancestor, a creature that
walked the wooded highlands of East Africa nearly 6 million years
ago.
The discovery, which occurred in the Middle Awash River Valley
of Ethiopia, is already challenging some existing theories about the
ancestral lineage of humans. It is also changing scientific views
about the nature of the environment that fostered the evolution of
pre-humans as they moved from verdant forests to open grasslands.
The team reporting the discovery in the July 12 issue of the journal
Nature was led by two Ethiopian scholars: Yohannes Haile-
Selassie, an anthropologist still working on his doctorate at the
University of California at Berkeley, and Giday WoldeGabriel, a
geologist now at UC's Los Alamos National Laboratory in New
Mexico.
Discovery Site in Ethiopia
The dry washes of the
Middle Awash River Valley
in Ethiopia are home to a
recent discovery of what is
believed to be the fossilized
remains of humanity's
earliest known ancestor.
Copyright 2001 National
Geographic Society
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.
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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 WoldeGabriel's 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 White's 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."
It's 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 today's 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
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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 continent's thick forests dwindled as a result of climate change.
But geochemical analysis of the ancient sedimentary soils where Haile-Selassie's 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 WoldeGabriel's 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.
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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 Ethiopia's 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.
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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 they're now documented by GPS, so they
won't get lost again. But we didn't 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
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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 don't 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
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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 doesn't 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."