HUMAN FOSSILS


New-found skull could sink our current ideas about human evolution July 2002 - Nature Magazine

After a decade of digging through the sand dunes of northern Chad, Michel Brunet found a skull 6-7million years old. He named it Touma�. Touma� is thought to be the oldest fossil from a member of the human family. It's a dispatch from the time when humans and chimpanzee were going their separate evolutionary ways.

Oldest fossil footprints on land - May 2002 - Nature
Hint that animals may have beaten plants out of the primordial seas


Recently discovered skeleton may prove early man, Neanderthals interbred

Reuters - April 20, 1999 - St Louis

A 24,500-year-old skeleton found in Portugal with characteristics found in both early modern humans and Neanderthals shows the two groups interbred and may be ancestors of modern man, a scientist said Monday.

The hybrid skeleton of what was likely a 4-year-old boy refuted the widely held theory that early humans emigrated from Africa and displaced the Neanderthal population without interbreeding, Washington University anthropologist Erik Trinkaus said.

The hybrid skeleton was the first evidence ever found that populations of early modern humans and Neanderthals interacted and interbred, Trinkaus said. "This skeleton shows a mixture of features that are features of modern man," he said in a telephone interview.

Many anthropologists support the so-called "Out of Africa" theory of human origins that says modern humans evolved in Africa and spread across the world about 100,000 years ago.

There is considerable evidence that Cro-Magnon people, who became modern humans, lived side-by-side with and interacted with Neanderthals, which died out about 30,000 years ago.

"This find refutes strict replacement models of modern human origins -- that early modern humans all emerged from Africa and wiped out the Neanderthal population," Trinkaus said.

Radiocarbon dating of the skeleton excavated in December showed it lived about 24,500 years ago, or 4,000 years after the time that early modern humans migrated across the Pyrenees and into the Iberian Peninsula where Neanderthals were already living, he said.

"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," Trinkaus said. He said the skeleton could not be dismissed as just a product of some unlikely, rare affair between members of the two groups.

"This is not a love child," he continued. "The results of admixture were there in the population 4,000 years after Neanderthals and early modern humans first met on the Iberian Peninsula."

A study published in 1997 of DNA taken from the Neanderthal skeleton discovered in Germany's Neander valley in 1856 indicated it was too distant genetically to have been an ancestor of modern humans. But Trinkaus said that merely proved that Neanderthals were not modern man, which was already known.

Though the skeleton's skull was crushed when a farmer bulldozed the then-undiscovered site six years ago, Portuguese archaeologists led by Portugal's director of antiquities, Joao Zilhao, subsequently found the well-preserved body and the intact lower jaw preserved in red ochre a few inches below the surface.

The prominent chin was characteristic of early modern humans while the stocky trunk and short limbs reflected its Neanderthal origins, Trinkaus said. Other arm bones pointed to early modern human parentage.

The skeleton was found when an archaeologist stuck his hand down a rabbit hole and pulled out the well-preserved skeleton's left forearm. The body was buried in red ochre, with a pierced shell, indicating a ritual burial, Trinkaus said.

The site is on a hillside near Leiria, Portugal, in the Lapedo Valley 80 miles north of Lisbon and 19 miles off the Atlantic Coast.


Researchers uncover fossil believed to be of human ancestor in Ethiopia

Addis Ababa, Ethiopia -January 10, 1999

Fossils of an apparent human ancestor believed to have lived 5 million years ago have been discovered in Ethiopia, a newspaper reported Sunday. A team of researchers representing 13 countries found the fossils in the Awash Valley, where the 3.2 million-year-old partial skeleton of an early hominid called Lucy, and known scientifically as Australopithecus afarensis, was discovered in 1974.

One of the researchers, Professor Tim White of the University of California at Berkeley, described the latest find as "extraordinary." Dr. Berhane Asfaw, an Ethiopian member of the team, said the fossil skull of a hominid believed to be 2 1/2 million to 3 million years old was also found at the site. Berhane said further tests would determine the significance and age of the fossils. The results will be available in about two years, he said.


3.6 million-year-old ape-man found in South Africa

Johannesburg--December 9, 1998 - Reuters

South African researchers said on Wednesday they had discovered the world's first near-complete skull and skeleton of an ape-man estimated to be 3.6 million years old. The four-foot-tall fossil was unearthed at Sterkfontein on the outskirts of Johannesburg and is estimated to be 3.6 million years old.

The oldest previous skeleton was 3.2 million year-old "Lucy," found in Ethiopia, while older specimens recovered from East Africa yielded only fragments of the whole frame. "The new find at Sterkfontein is, therefore, the oldest hominid skeleton yet discovered anywhere in the world," said Tim Partridge. He, together with the Geomagnetism Laboratory of the University ofLiverpool, assessed the age of the fossil.

Professor Phillip Tobias said the age of the fossil would also help to provide clues to the debate on when some apes had evolved into humans. "We're getting down nearer to the critical parting of the ways between apes and us -- perhaps five to seven million years," Tobias said. Ron Clarke, director of excavations at Sterkfontein, said preliminary evidence showed that the ape-man not only walked upright, but was also a tree climber.

"We are at a time where humankind was experimenting with two-legged motion and we really do need full information on how they moved and ultimately that tells us what their lifestyle was," said Professor Hilary Deacon at Stellenbosch University. "We need to know what these first stages in becoming human were about and I think it's a very exciting find in those terms. The full significance of the find would emerge once it was recovered from a 45-foot-deep limestone shaft. What we already know is it will reveal a very great deal about the anatomy and evolution of an earlyape-man."

"Just one bone would be exciting but this is apparently the whole skeleton -- the secret to knowing how the creature functioned. This eliminates any speculation," said Tobias. "It is the most important find out of South Africa since the Taung skull was found in 1924 this probably exceeds that in importance," he said. Past finds of ape-man fossils, including the oldest hominid bones in East Africa, have only been partial skeletons.

Professor Deacon said the South African discovery linked southern Africa with East Africa -- which has long been believed to be the cradle of modern man --and underscored the importance of sub-Saharan Africa to the study of the origins of humankind.

"I think it's a very notable achievement. One needs to know how these creatures moved and having more of the skeleton is extremely important," Deacon said. The discovery followed three years of work after Clarke chanced on four hominid footbones while looking in a box labelled "animal bones" which were collected from a cave at Sterkfontein on the outskirts of Johannesburg. The footbones led him to believe that the rest of the skeleton must be fossilized in the cave. Clarke's assistants, Nkwane Molefe and Stephen Motsumi, spent a year in the dark, wet cavern chipping away at the limestone looking for the skeleton. Clarke said there were signs of further hominid fossils at Sterkfontein, site of more than 600 other fossil discoveries which South Africa has nominated as a World Heritage site.

"Up to now Australopithecus of that antiquity have only been found in east and central Africa so it's really thrilling that they came down this far," said Dave Roberts, a geologist with the Council for Geoscience. "It does increase the possibility that the first modern humans arose in southern Africa and they may have migrated north" he said. Roberts said the age of the new ape man tied in with the footprints discovered in northern Tanzania which provided the first conclusive evidence of ape-like creatures walking upright.



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