Thursday, 1 October 2009
By Jonathan Amos
Science reporter, BBC News
An ancient ape-like creature that may be a direct ancestor to our species has been described by researchers.
The assessment of the 4.4-million-year-old animal called Ardipithecus ramidus is reported in the journal Science.
Even if it is not on the direct line to us, it offers new insights into how we evolved from the common ancestor we share with chimps, the team says.
Fossils of A. ramidus were first found in Ethiopia in 1992, but it has taken 17 years to assess their significance.
The most important specimen is a partial skeleton of a female nicknamed "Ardi".
The international team has recovered key bones, including the skull with teeth, arms, hands, pelvis, legs, and feet.
But the researchers have other fragments that may represent perhaps at least 36 different individuals, including youngsters, males, and females.
One of the lead researchers on the project, Professor Tim White from the University of California at Berkeley, said the investigation had been painstaking.
"It took us many, many years to clean the bones in the National Museum of Ethiopia and then set about to restore this skeleton to its original dimensions and form and then study it and compare it with all the other fossils that are known from Africa and elsewhere as well as with the modern age," he told the journal.
"This is not an ordinary fossil. It's not a chimp. It's not a human. It shows us what we used to be."
The fossils come from the Middle Awash study area in the Afar Rift, about 230km northeast of Addis Ababa, Ethiopia's capitol.
Some of the characteristics of the animal's skeleton are said to echo features seen in ancient apes; others presage traits seen in later, human-like species.
The scientists say Ardi was good at climbing trees but also walked on two feet. However she did not have arched feet like us, indicating that she could not walk or run for long distances.
What is surprising about the discovery is that the remains were found in a forested area. It had been thought that early human evolution was prompted by the disappearance of trees - encouraging our ancestors to walk on the ground.
"These creatures were living and dying in a woodland habitat, not an open savannah," said Professor White.
http://news.bbc.co.uk/1/hi/sci/tech/8285180.stm
Subscribe to:
Post Comments (Atom)
Posts
No comments:
Post a Comment
You only need to enter your comment once! Comments will appear once they have been moderated. This is so as to stop the would-be comedian who has been spamming the comments here with inane and often offensive remarks. You know who you are!