Humans may have left Africa for Eurasia earlier than believed
These small hand axes are at least 100,000 years old. A team of scientists found these tools in the United Arab Emirates.
January 27th, 2011
03:45 PM ET

Humans may have left Africa for Eurasia earlier than believed

Scientists have discovered new evidence suggesting that modern humans first left Africa to explore Eurasia much earlier than previously thought.

An international team of scientists has uncovered a tool kit that indicates that modern humans, who looked and perhaps behaved much like us, must have lived in eastern Arabia about 100,000 to 125,000 years ago. The collection of small hand axes, scrapers and other tools was found in Jebel Faya, United Arab Emirates. A report about the discovery appears in the journal Science.

The people who made these tools "are our ancestors, I have no doubt about that," said Hans-Peter Uerpmann, of the University of Tubingen in Germany, who collaborated on the project, at a press teleconference Wednesday.

But the findings still do not prove definitively that modern humans made these tools, as the researchers did not find human remains near them, said Ted Goebel, anthropologist at Texas A&M University, who was not involved in the study. They potentially could have been made by Neanderthals or Neanderthal-like hominids, who were already in Eurasia at that time, Goebel said.

Previous research suggested that modern humans first left Africa along the coast by way of the Indian Ocean rim about 60,000 years ago, based on genetic evidence.

But the tool kit suggests that humans arrived on the Arabian Peninsula much earlier. Scientists say the tool shapes, indicative of what would have been made in Africa, indicate that humans did not need technological innovation to get there.

Stanley Ambrose, an anthropologist at the University of Illinois who was not involved in the research, agreed that the structure of the axes found at the site are indicative of human-made objects from East Africa.

But, as Goebel said, human skeletons are needed to prove the connection.

"It's in Africa they produce hand axes, but also what are called foliates, leaf-shaped bifacial pieces. These simply do not occur in the rest of southwest Asia," Anthony Marks, study co-author and retired professor at Southern Methodist University in Dallas said at the teleconference.

Instead, the researchers say, environmental factors aided the humans' departure. There was a global ice age between 200,000 and 130,000 years ago, during which global sea levels fell and desert belts expanded, Marks said. During that time, modern humans would have had to stay in East Africa, as it would have been hard to cross the deserts.

But then, warmer temperatures came in about 130,000 years ago in the "interglacial" period, giving way to savanna grasses with lakes and rivers. Around that time, Marks said, the southern Red Sea had water levels about 328 feet (100 meters) lower than what's found there today, and was also much narrower. This would have facilitated an easier crossing into Arabia.

The humans could have walked, or used rafts or boats, which they were capable of making, Uerpmann said. Their descendants may have moved toward the Persian Gulf, which was smaller then, and into Mesopotamia, or eastward along the Iranian coast to the Indian subcontinent, he said.

Although there has been extensive genetic study pointing to humans' departure 60,000 years ago, there is no archaeological evidence for this, Marks said. Genetics give a sequence of happenings, but cannot say how and when the events occurred, Uerpmann said. The archaeological record is better than genetics for this reason, he said.

Still, Goebel says he is cautious because the method for dating in the study, called luminescence dating, is not much more precise than extrapolating dates from genetics, and gives a large range of possible dates of origin for objects.

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soundoff (215 Responses)
  1. RobA

    FreedomBaby said:

    "If science is so accurate why do they have to keep changing their theories?"

    It is BECAUSE of the fact that science adjusts to accomodate new information that it is a more accurate explanation.

    Religious theories make an assumption, and then twist the facts to support that assumption, and stubbornly ignore anything that doesn't support or outright disproves their belief.

    Science adjusts and corrects itself. You could even say that scientific theories "evolve." That is, unless you've decided ahead of time that there is no evolution. In which case, you're on ground that's no more solid than that of someone who doesn't believe in gravity or atomic theory.

    January 28, 2011 at 10:08 am | Report abuse |
  2. sissycanthropus

    That mean old god of the old testament! He sucks! I don't want to be in his heaven anyway! In fact, that mean old God can go to hell himself! His entire modus operandi was to fool people and make life miserable. First, he used the snake to fool Eve, then he used Eve to fool Adam. He also planted Australopithecus, H habilis, H erectus, Neanderthal, and early human fossils and their Olduwan, Mousterian, and Auragnacian tools around Africa and Europe to fool scientists and the whole world! I like the devil better!

    January 28, 2011 at 10:16 am | Report abuse |
  3. Nitalynn

    I find it interesting the the suspected Toba bottleneck in human evolution occurred between the tentative dating of the toolkit and the accepted date of the migration from Africa. I can't help but wonder if there was an earlier diaspora that was caught and exterminated by the devastation. If so this would mean there was something about the situation in Africa that allowed the human population to survive there and not elsewhere. If so it would behoove us to spend some time and attention trying to figure out what is was as watch the sensors at Yellowstone with a wary eye.

    January 28, 2011 at 11:00 am | Report abuse |
  4. Philip

    If mankind has been here for over 100,000 yrs., we would have found thousands of fossilized human skeletons by now just like we have with other animal species. And please stop confusing what the church says with what the bible says. Today's religions make a mockery of God and make him appear to be foolish and mean. The bible does NOT say the universe was created in a few days, and does NOT teach that god would allow his disobedient children to be burned alive. Those lies are spouted by preachers who fleece their flocks, and priests who stalk boys. Even those who do not believe in God believe quote these liars rather than the bible. very peculiar behavior.

    January 28, 2011 at 12:19 pm | Report abuse |
  5. Philip

    @goat...Moses didn't build the ark. Noah did. It took him over 50 years to complete, and was bigger than Yankee Stadium. He didn't need 2 of every single type of lizard, he just need a few who would eventually crossbreed over time and give us the diversity of lizards we see now. And even science agrees that there was a worldwide deluge. Fossilized ocean life can be found virtually everywhere, except the fossilized skeletons of humans wh scientists say may have lived 100,000 yrs ago. Millions of complete fossilized skeletons of every single animal species except one: humans of the species.

    January 28, 2011 at 12:27 pm | Report abuse |
  6. Cesar

    @Philip: How old was Noah when he completed the ark? What did he do for wages? What was the cost of the ark by today's American dollars. I'm asking because I was just wondering.

    January 28, 2011 at 3:31 pm | Report abuse |
  7. Philip

    Cesar, the answers to your questions have been available for you to read for thousands of years. I invite you to read your bible for the answers. Why take mine or some preachers word on it? The account recorded in the bible concerning Noah and how the world was back then is a fascinating read. As you read, think of how things back stack-up to how things in the world are today. The similarities are amazing. Thanks for being interested enough to ask, and happy reading!

    January 28, 2011 at 5:15 pm | Report abuse |
  8. nepawoods

    God to leave a little early in case you hit traffic.

    February 9, 2011 at 8:28 am | Report abuse |
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