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morfrain_encilgar
Thursday, February 17th, 2005, 01:26 AM
Two skulls originally found in 1967 have been shown to be about 195,000 years old, making them the oldest modern human remains known to science.
The age estimate comes from a re-dating of Ethiopian rock layers close to those that yielded the remarkable fossils.

The skulls, known as Omo I and II, push back the known presence of Homo sapiens in Africa by 40,000 years.

The latest dating work is reported in the science journal Nature.

It puts the specimens close to the time expected for the evolutionary emergence of our species. Genetic studies have indicated Homo sapiens arose in East Africa - possibly Ethiopia or Tanzania - just over 200,000 years ago.

"These are the earliest known examples of our own species and that suggests they lived earlier still," commented Nature senior editor Dr Henry Gee.

"But I am not sure how much further back you could go and still have Homo sapiens - before they graded into some other, earlier species," he told the BBC News website.

Dig return

The skulls were first brought to the attention of the world by the famous fossil hunter Richard Leakey, whose team unearthed the specimens in sediments along the Omo River in southernmost Ethiopia, near the town of Kibish.

They found the skull (minus the face) and partial skeleton (parts of arms, legs, feet and the pelvis) of Omo I, and the top and back of the skull of Omo II.

Now, a three-man Australian-US team - Ian McDougall, Frank Brown and John Fleagle - has re-evaluated the Leakey finds.

The team even returned to the original excavation area, using old scientific reports, photographs and film to identify the precise dig co-ordinates.

"Omo I actually has the better information on it," explained co-author Professor Brown, from the University of Utah's College of Mines and Earth Sciences.

"[The records and maps] are correct and we actually went back and found a few more pieces of the skeleton and some of them glue on to the pieces that were found in 1967."

Climate clincher

The original dating in 1967 found the fossils to be 130,000 years old.

This was based on the decay rate of radioactive uranium atoms contained in oyster shells found near the skulls - "but that date should always have been taken with a pinch of salt", Professor Brown told BBC News.

"Molluscs are not really very good for that kind of thing."

The new results, though, are regarded as far more robust. They depend on the known decay rate of radioactive atoms of potassium-40 into the gas argon-40 in feldspar mineral crystals.

These crystals were retrieved from chunks of pumice in volcanic ash layers above and below the skulls.

They suggested the specimens must be between 104,000 and 196,000 years old - but with some additional climate evidence on ancient flooding in the region, the team was able to show the Omo finds were actually very close to the 196,000-year mark.

The previous oldest Homo sapiens skulls were uncovered in sediments near a village called Herto in the Afar region in the east of Ethiopia. These were dated to between 154,000 and 160,000 years old.

To be human

Although researchers are pushing at the evolutionary base of our species, they still have much to discover in terms of these early people's behaviour.

Professor Brown explains: "...the cultural aspects of humanity in most cases appear much later in the record - only 50,000 years ago - which would mean 150,000 years of Homo sapiens without cultural stuff, such as evidence of eating fish, of harpoons, anything to do with music (flutes and that sort of thing), needles, even tools.

"This stuff all comes in very late, except for stone knife blades, which appeared between 50,000 and 200,000 years ago, depending on whom you believe."

Professor John Fleagle, of New York state's Stony Brook University, adds: "There is a huge debate in the archaeological literature regarding the first appearance of modern aspects of behaviour such as bone carving for religious reasons, or tools, ornamentation (bead jewellery and such), drawn images, and arrowheads.

"They only appear as a coherent package about 50,000 years ago, and the first modern humans that left Africa between 50,000 and 40,000 years ago seem to have had the full set.

"As modern human anatomy is documented at earlier and earlier sites, it becomes evident that there was a great time gap between the appearance of the modern skeleton and 'modern behaviour'."

Agrippa
Thursday, February 17th, 2005, 01:55 AM
"As modern human anatomy is documented at earlier and earlier sites, it becomes evident that there was a great time gap between the appearance of the modern skeleton and 'modern behaviour'."

I would suggest that mainly new areas, new biotops, were responsible for the furthere sapiens evolution. As long as they lived in the Savannah from which they were from, they were like animals in their own biotop without too much need for revolutionary adaptations.

Triglav
Thursday, February 17th, 2005, 02:02 AM
Great. What is your source, atlanto-med?

morfrain_encilgar
Thursday, February 17th, 2005, 02:07 AM
Great. What is your source, atlanto-med?

Its BBC news for this one, Triglav.

Triglav
Thursday, February 17th, 2005, 02:15 AM
Its BBC news for this one, Triglav.
Thank you.

Do you happen to have a link to the source? I googled for it but couldn't find it.

Triglav
Thursday, February 17th, 2005, 02:25 AM
Pictures.


Omo I:

http://www.modernhumanorigins.com/hominids/omo1front.jpg

http://www.modernhumanorigins.com/hominids/omo1rside.jpg



Omo II:

http://www.modernhumanorigins.com/hominids/omo2lside.jpg

morfrain_encilgar
Thursday, February 17th, 2005, 02:30 AM
I would suggest that mainly new areas, new biotops, were responsible for the furthere sapiens evolution. As long as they lived in the Savannah from which they were from, they were like animals in their own biotop without too much need for revolutionary adaptations.

Are you suggesting that sapiens migrated back into Africa? In moderns, the tropical populations of Africa and Asia certainly retained the most archaic features when theyre compared to northern Eurasian races.

Agrippa
Thursday, February 17th, 2005, 02:53 AM
I would say that even the tropical rainforest regions were a new challenge for the archaic sapiens.

If its about the African Europids and partly the Aethiopids, I'm quite sure they came back from outside of Africa.
Because the primitive sapiens of the Savannah were the (more primitive) ancestors of the modern Khoisanids, as you know.

I thought about back migration of Negrids as well, it might be possible, but I wouldnt favour such an explanation at the moment.

Dr. Solar Wolff
Thursday, February 17th, 2005, 05:27 AM
All very old sapiens I know of were found near the ocean. This find mentions association with oyster shells. It seems to me that sapiens did not differentiate itself on the savannah but on the beach. It also seems that sapiens lived as Blacks live in Africa today rather than as even Neanderthals lived until they entered Europe at least Asia. In other words, there is no cultural difference between sapiens and non-sapiens in Africa for a long time, if ever.

Bismark
Thursday, February 17th, 2005, 08:33 AM
Interesting article.

We can discuss human evolution all day, but the fact is the innovation, the intelligence, and the ambition that makes humans humans is not nearly as old as the human species. 175 thousand years ago we have evidence of the existence of modern humans, but only 50 thousand years ago do we have evidence of humans acting human. That means for a 125 thousand years, or more than 2/3rds of our existence as a species although anatomically human we behaved very much like animals (probably much like today’s primates).

Then something happened. Something changed. A profound change that affected all humans for the next 50 thousand years, and only be came more rapid as time went on. But what was the change? What led us from beginning ceremonial burial, crude art, and musical instruments 50 thousand years ago, to farming, making pottery, and forming city's 8 thousand years ago, to developing a written language, creating the wheel, and sailing 4 thousand years ago, to beginning to understand science and, developing medicine 2 thousand years ago.....to developing computers, and television 60 years ago? Answer those questions and you'll answer the question ‘what is humanity, what is it to be human?'

morfrain_encilgar
Thursday, February 17th, 2005, 11:32 AM
We can discuss human evolution all day, but the fact is the innovation, the intelligence, and the ambition that makes humans humans is not nearly as old as the human species. 175 thousand years ago we have evidence of the existence of modern humans, but only 50 thousand years ago do we have evidence of humans acting human. That means for a 125 thousand years, or more than 2/3rds of our existence as a species although anatomically human we behaved very much like animals (probably much like today’s primates).

The biggest change in human ecology seems not to have been when humans started to think more like humans, but with food production. Until then sapiens functioned like other primates, but with their own ecological place, even after the earliest evidence for modern thought thats generally accepted to be evidence for modern thinking.

Edwin
Friday, February 18th, 2005, 06:45 AM
What could Neaderthal have had 50,000 years ago that we didn't, and could acceptance of that have been our event? What about something to do with the otherworld/divine which profoundly affected social structure?

Lidvick
Friday, February 18th, 2005, 06:56 AM
These are very interesting scientific finds however , a subject going thousands of years back will be very difficult to piece all things together.:) :thumbup


All we can do is theorize and make estimate guesses that is why I always think there is only so much as human beings we are allowed to know lol.;)

I think our creator is somewhere thinking I will not let you know everything only I your creator can know everything. ( crude joke probally not funny shrugs).

Dr. Solar Wolff
Friday, February 18th, 2005, 07:42 AM
Interesting article.

We can discuss human evolution all day, but the fact is the innovation, the intelligence, and the ambition that makes humans humans is not nearly as old as the human species. 175 thousand years ago we have evidence of the existence of modern humans, but only 50 thousand years ago do we have evidence of humans acting human. That means for a 125 thousand years, or more than 2/3rds of our existence as a species although anatomically human we behaved very much like animals (probably much like today’s primates).

Then something happened. Something changed. A profound change that affected all humans for the next 50 thousand years, and only be came more rapid as time went on. But what was the change? What led us from beginning ceremonial burial, crude art, and musical instruments 50 thousand years ago, to farming, making pottery, and forming city's 8 thousand years ago, to developing a written language, creating the wheel, and sailing 4 thousand years ago, to beginning to understand science and, developing medicine 2 thousand years ago.....to developing computers, and television 60 years ago? Answer those questions and you'll answer the question ‘what is humanity, what is it to be human?'

Polygenetic genes are additive. That means that the more genes one gets to be tall, the taller he is. This works for intelligence also. So, what happens if two different but intelligent species mate with different loci for genes of intelligence? They all become additive and the offspring is even more intelligent than would have otherwise have been predicted. Could this have happened 50,000 years ago when and if sapiens picked up some Neanderthal genes? With totally new genes for intelligence and ones differing from other sapiens, the resulting hybrids might have not only been intelligent but intelligent in ways never seen before.