Skip to comments.New Out-Of-Africa Theory Unveiled
Posted on 02/27/2002 4:56:58 PM PST by blam
New Out-of-Africa Theory Unveiled
By Larry O'Hanlon, Discovery News
Leaving the Mother Country
Feb. 25 The human family just got even smaller.
Everyone outside of Africa Asians, Europeans, Native Americans, Southeast Asians, Australian Aborigines, etc. came from the same small band of humans that left the mother continent some 80,000 years ago by way of Ethiopia, according to a new theory unveiled Monday by geneticists and DNA detectives.
"No, we haven't found the bones of the original Eve," said DNA tracker Stephen Oppenheimer of Oxford University in a press teleconference.
Instead, researchers have followed the trail of mitochondrial DNA, which we inherit unchanged from our mothers, and backtracked down the branching tree of the human family throughout the world.
If the mitochondrial DNA story is correct, then we all descend from a woman who lived in Africa 150,000 years ago, said geneticist Martin Richards of Huddersfield University in England, who also took part in the briefing.
Oppenheimer and Huddersfield will appear in "The Real Eve," a Discovery Channel documentary premiering on April 21.
What's more, all non-Africans come from a small group of people who ventured out of Africa some 80,000 years ago, perhaps because of climate changes along the Red Sea shore that made life there too difficult, he said.(maybe it dried up during the Ice Age, huh?)
Genetic evidence of that small band can be found today in India, said Oppenheimer. "In India, all of the early lines that gave rise to Asians and Europeans are found in great profusion and great antiquity," he said.
For years anthropologists have debated whether humans left Africa by a northern route via the present-day Suez Canal region or by a southern route, via a short-lived isthmus connecting Ethiopia to Yemen at the southern end of the Red Sea. Some researchers have even suggested that Europeans descend from the people of the northern exodus and the rest of non-Africans from the people of the southern exodus.
But the DNA just doesn't support dual routes, said Oppenheimer and Richards.
"The fact that we look different is because we live in different environments," said Oppenheimer. "(But) we are really, truly the same under the skin."
The single exodus theory also meshes well with other genetic and archeological discoveries. Last year, researchers working on the Human Genome Project reported that the pool of human genetic material is startlingly small, implying we are a young species and come from a very small group of Africans.
However, not everyone is convinced of the single group theory, said paleontologist Tim White of the University of California at Berkeley. "My sense in it is that we're not close to the bottom line yet," he told Discovery News.
Genetics has yielded some new data to the mix, he said, but the smoke hasn't yet cleared enough to see the details of exactly when and where modern humans came out of Africa.
The Homo erectus of China (Peking Man) of 400,000 years ago had specific dental and cranial traits that are unique to present-day Asians.
Explain that, PC-liars.
By "we" does he mean all non-africans, or everyone.
Well, Phoenicians have lived in North Africa for several millennia by now -- a period of time comparable to that from the initial alleged exodus. How come no poeple seem to develop Negroid features because it lives in Africa after migrating from elsewhere?
Is it possible that Homo erectus evolved at several places on earth in stages? The Peking Man would have evolved first into modern man, others evolved later. Would the evolutes all have the same DNA? That hypothesis is popular in China.
This gives me hope that I an all white team will one day win the NBA trophy. Not.
Never the less I'd like to hear it from Pharmboy himself.
That, sir, is a softball. I have been in science my whole life and have a great deal of respect for data. When politics drives pronouncements based on contradictory data it ceases to be science. Stephen Jay Gould is the mother of all anthropology/evolution liars. They disregard contradictory evidence (and there is much).
Further, I infer from your question that you think I have an ulterior motive in lambasting this lunacy, i.e., I am a racist. You, perhaps are a liberal. Read more on the subject starting with the site I linked.
You do not sound like a mensch to me.
Just by way of timing for the last Pleistocene glacial event, oxygen-16/oxygen-18 ratio studies from ice cores in Greenland and the antarctic tend to show a similar trend. The end of the last interglacial (warm period) came about 125,000 years before the present (b.p.). There was then a general cooling trend until about 100,000 years b.p. From 100,000 b.p. to 85,000 b.p. there was a slight "warming" but the raios still indicate a cool period. The ratios then drop off again and reach a minimum about 20,000 years ago. That point is generally considered to be the "height" of the last Ice Age. Since then there has been a steady warming trend. Today the oxygen isotope ratios are about what they were 125,000 years ago.
The melting of the North American and Asian ice sheets would readily explain the jump in eustatic sea level from the lows at 10,000 b.p. to the levels of 6,000 b.p. - which are near the levels of today.
I believe the evidence of from the oxygen isotope fluctuations and eustatic sea level change will certainly figure into the development of early human societies.
Whats that make you, a pharmacist?
When politics drives pronouncements based on contradictory data it ceases to be science. Stephen Jay Gould is the mother of all anthropology/evolution liars. They disregard contradictory evidence (and there is much).
Don't know about Mr. Gould, his research practices, or whether he's a liar, or not. I suspect you may have some shortcomings of your own regarding contradictory evidence.
Further, I infer from your question that you think I have an ulterior motive in lambasting this lunacy, i.e., I am a racist.
I didn't think you were a racist, but I had a suspicion. Glad to hear from you that such is not the case. Racist posts give credence to liberals, who wish to give this forum a bad name.
You, perhaps are a liberal. Read more on the subject starting with the site I linked.
Sorry I can't reinforce your particular prejudices, but I'd probably be considered middle right by everyone except evangelicals (no disrespect to fundementalists intended) Ideologues can also give this forum a bad name.
You do not sound like a mensch to me.
Yawn... Howcome everyone with whom I have the temerity to question, arrives at the same conclusion, stated more or less the same way? I do, or do not, agree with you hence I am, or am not, a Mensch?
i.e., I am a racist. A bit extreme, wouldn't you say? One could also infer that you, like the scientists you justly criticize, may be married to an alternative idea --- such as multi-regional origin, for instance. No one has implied that you are a racist thus. Were Mensch to do so, you would be rightfully offended; he did no such thing, however.
You, perhaps are a liberal. All this is referred from Mensch's question? And, despite the contradictory evidence that he, Mensch, is spending time on this, rather than some liberal, board?
You do not sound like a mensch to me. Again, all this is inferred from a question? A respect your scientific honesty and that, as you write, you "have been in science [your] whole life and have a great deal of respect for data." It is not that often that well-trained scientists have problems with data --- it is misapplication and illogical conclusions drawn on the basis thereof that gets them in trouble.
It is sad for me to see two clearly intelligent and scientifically honest people being on the verge of calling each other names on the basis of what has not been said.
Actually, both of you look like mensches to me.
I thought we evolved from a group of ape-like ancestors, who evolved from reptiles, who evolved from one cell organisms.
Now they're saying that one woman was responsible for it all? So our ancestry time line is like an hour glass: Millions of years of evolution produced this woman, who through her progeny produced millions of us. Fascinating.
Yes. But she had multiple partners. I always wondered where that term "the oldest profession" came from.
YOU: Whats that make you, a pharmacist?
ME NOW: There you go again, making an INCORRECT inference. No--I am not a pharmacist, but would not be ashamed if I were one. Not only are you wrong AGAIN, but you show your prejudice agaist someone you think is not as bright as you are, or perhaps does not make as much money as you. Shame on you.
ME: When politics drives pronouncements based on contradictory data it ceases to be science. Stephen Jay Gould is the mother of all anthropology/evolution liars. They disregard contradictory evidence (and there is much).
YOU: Don't know about Mr. Gould, his research practices, or whether he's a liar, or not. I suspect you may have some shortcomings of your own regarding contradictory evidence.
ME NOW: If you do not know who Gould is then you cannot be very well read in this subject matter. The scientific method (which--if you are not schooled in science please look up) advances by looking at data and putting forth hypotheses which can be falsified by experiments. Unfortunately, much in the way of paleoanthropological data CANNOT be falsified and therefore must remain quite speculative. I do NOT ignore good data; if I did, the whole basis of my worldview and intellectual honesty would be BS. This I will not do wherever the facts take me...this is why I rail against the pc pseudo-scientists. And BTW: there is NO DOUBT WHATSOEVER that humanity emerged from Africa. What the debate about has to do with details and timing.
ME: Further, I infer from your question that you think I have an ulterior motive in lambasting this lunacy, i.e., I am a racist.
YOU: I didn't think you were a racist, but I had a suspicion. Glad to hear from you that such is not the case. Racist posts give credence to liberals, who wish to give this forum a bad name.
ME NOW: Well...merely having a problem with PC data makes you suspicious that I am a racist. Some advice: before you do that to a poster on this or any other forum, check out their other posts to see if there is a pattern. Another illustration of the scientific method of checking out an hypothesis (i.e., "suspicion").
ME: You, perhaps are a liberal. Read more on the subject starting with the site I linked.
YOU: Sorry I can't reinforce your particular prejudices, but I'd probably be considered middle right by everyone except evangelicals (no disrespect to fundementalists intended) Ideologues can also give this forum a bad name.
ME NOW: Goodness: everything gives this forum a bad name except you. Any nosebleeds atop that high horse?
ME: You do not sound like a mensch to me.
YOU: Yawn... Howcome everyone with whom I have the temerity to question, arrives at the same conclusion, stated more or less the same way? I do, or do not, agree with you hence I am, or am not, a Mensch?
ME NOW: Okay--this may be difficult for you so I will type s-l-o-w-l-y: You did NOT "question" me on facts or substance; you questioned my MOTIVES and implied a racist undertone to my post. That is acting like a liberal and therefore I assumed if it walks like a duck, etc. Have a pleasant PC day.
Must be an Adam out there somewhere?
As long as scientists make this claim it's considered legitimate. Were a Christian to make the same claim he would be and is widely derided as a kook.
African Eve or multiregional origins? Maybe both
WASHINGTON (Reuters) The out-of-Africa theory is not dead, anthropologists and other experts say this week, despite two recent studies that challenge the idea we are all descended from a single African "Eve."
U.S. and Australian researchers published two reports that used physical and genetic evidence to suggest there may have been mixing of pre-humans with modern species.
They said they had proved wrong the mainstream out-of-Africa theory that the ancestors of all living humans emerged from Africa some 50,000 years ago and either killed off or out-competed all other humanlike creatures who settled across much of the world.
One study used genetic evidence that suggested "Mungo Man," an Australian skeleton dated to between 40,000 and 60,000 years ago, is genetically unrelated to Africans. The researchers, Gregory Adcock of Australian National University and colleagues, said their finding showed the first modern humans evolved in Australia, not Africa.
Another, published in Friday's issue of the journal Science, analyzed physical features of early human skulls to suggest there must have been interbreeding among the migrating Africans and resident Neanderthals and even Homo erectus species of prehumans.
"There never was a marauding band of Africans," University of Michigan anthropologist Milford Wolpoff, who led the second study, said in a telephone interview.
"It certainly means that the "Eve" theory, the replacement theory, seems to be wrong."
The Australian team and Wolpoff and colleagues belong to the "multiregionalist" school of human evolution. They believe humans evolved around the world at roughly the same time, and that they probably mixed with earlier species such as Neanderthals and Homo erectus.
The out-of-Africa school says that all earlier humans died out and were replaced by a small group from Africa who quickly conquered the world.
Some experts say the two theories are not incompatible, although they predict a fight over the latest studies.
"There might be a lot of finger-pointing and name calling and debate that is more heat than light," says Peter Underhill of Stanford University, who has published genetic studies that date our common ancestors to an African man who lived 59,000 years ago and an African woman who lived 143,000 years ago.
"But I don't think it torpedoes the recent out-of-Africa scenario at all. I don't think these two papers are going to turn the world of human evolution on its head."
It does not matter whether early humans mixed or evolved into "modern" forms in more than one place, Underhill says. The out-of-Africa theory holds only that one lineage finally held sway, either through luck, better genes, or a combination of the two.
We are all descended from that lineage, he says. "Everyone on Earth today is very closely related," he says.
"It might suggest that there was some hybridization with moderns and possibly other modern lineages that existed 60,000 years ago that are now extinct, or it is possible there was some kind of hybridization with some sort of archaic human that lived in the past," Underhill adds.
"But no one is walking around so far in Europe with Neanderthal genes."(I believe this is false)
So if both theories can coexist, why argue?
"Egos, egos egos," Underhill says. "Scientists are human."
Clark Howell, a professor emeritus of human evolution at the University of California Berkeley, agrees.
"There is a tendency in some instances for some people at some times to jump to very wide, sweeping conclusions," he says. "In my view these two studies don't upset any applecarts."
In other words, modern humans may have indeed evolved in places other than Africa. They may even have mated occasionally with Neanderthals, who did live at the same time and in the same places. But genetically, they have since died out.
"If we are looking for the ancestry of modern people, where people alive today came from, where their genes came from if there was such hybridization it is negligible. It is impossible to find today," says Chris Stringer, head of human origins at London's Natural History Museum and an architect of the out-of-Africa theory.
For my money, this was the most intelligent statement in the entire article.
Written by Janel Bladow.
NEW YORK, April 19 (UPI) - The centuries-old body of a 4-year old child found buried in central Portugal is creating a sensation in scientific circles as it links the Neanderthal to modern man. The child's remains show characteristics of both, which until now, many thought did not interbreed. "This find tells us about what it means to be human," Erik Trinkaus, professor of anthropology, arts and sciences at Washington University in St. Louis, told UPI in an interview today. Trinkaus is working directly with Joao Zilhao, Portugal's director of antiquities who is overseeing the excavation team.
"This skeleton, which has some characteristics of Neanderthals and others of early modern humans, demonstrates that early modern humans and Neanderthals are not all that different. They intermixed, interbred and produced offspring," he said. "Many people like to distance themselves from Neanderthals," said Trinkaus. "The significance of this discovery is that many believe when modern men spread across Europe, they displaced those who were already there. They believe the Neanderthal died out without issue. This refutes that argument."
The child is believed to be a 4-year-old boy who lived 24,500 years ago. He has a chin, a clear characteristic of early modern humans; Neanderthals did not have chins. But he also has a stocky body and short limbs, the body proportions of Neanderthals. Modern men had liner bodies and long limbs. The skeleton was found in the Lapedo Valley north of Lisbon in Portugal, buried on a hillside with a pierced shell and red ochre, which indicates a ritual burial. Radio-carbon dating confirms that the skeleton is 24,500 years old, 4,000 years after the time that Neanderthals and early modern humans co-existed on the Iberian Peninsula.
"This is pretty exciting," said Trinkaus. "It is the first paleontologic burial discovered in Iberia. It is a ritual burial. We can tell that because the body was covered with red earth, called red ochre. And it was buried with a pierced shell by its neck. This places its time period around 20,000-30,000 range. "In ritual burials at that time, bodies were covered with varying amounts of ochre on them, an obvious analogy to blood. Almost all of these burial included a pierced shell or animal teeth, that of a fox or bear. Beyond this we don't know the significance of the ochre or the shell or teeth. "What is clear though, is that this is the burial of a 4-year-old child and that either everyone had these types of burials or this individual had some status from its parents."
Since the Nov. 28 discovery of the burial site and Dec. 5 when scientists stumbled on the child's body - a Portuguese biologist reached into a rabbit hole and pulled out a limb - only a small portion of the skeleton has been pieced together. Another significant aspect of the discovery is that the child lived about 4,000 years after early modern humans moved into the Iberian Peninsula. This means that the two populations lived there together for a few thousand years. "This was not a chance mating, this is a case of population intermixing," said Trinkaus. "The other thing this says is that whatever these people look like to us, back then, they were all were just humans. Hunters and gathers all living on land and meeting up to become one population which then evolved and became various groups.
"The broader issue here is that some people want to make the Neanderthal different from us. They want modern humans to be special. But the modern man isn't all that special in the greater scheme of things," says Trinkaus. Also significant in the discovery is that the child was found on the Iberian Peninsula only 24,500 years ago, said Fred Smith, professor of anthropology at Northern Illinois University in DeKalb. "This shows the exchange between Neanderthal and modern man to be more recent in time." He told UPI. "I thought it would be 30,000 years ago. The big debate has been if the Neanderthal contributed to gene pool in Europe. This suggests that there was some assimilation of the Neanderthal into the early modern gene pool."
The skeleton is being pieced together at the National Archeology Museum in Lisbon by an international team. They will be studying the health of the child, called Lagar Velho 1 (old wine press after the name of site), aspects of its growth, and other genetic information. Scientists plan to return to the site in July. The area was first bulldozed by builders six years ago and the child's grave was missed by 2 inches. At Christmas some 2,000 people came to see where the child was found. Older village women admonished the scientists to "take good care of our boy," says Trinkaus.
A. HHMMMMmmmmmm, let me see, Oh yeah, it was on the sixth day.