Thursday, October 1, 2009

Oldest Human Fossils

WASHINGTON – The story of humankind is reaching back another million years as scientists learn more about "Ardi," a hominid who lived 4.4 million years ago in what is now Ethiopia. The 110-pound, 4-foot female roamed forests a million years before the famous Lucy, long studied as the earliest skeleton of a human ancestor.

This older skeleton reverses the common wisdom of human evolution, said anthropologist C. Owen Lovejoy of Kent State University.

Rather than humans evolving from an ancient chimp-like creature, the new find provides evidence that chimps and humans evolved from some long-ago common ancestor — but each evolved and changed separately along the way.

"This is not that common ancestor, but it's the closest we have ever been able to come," said Tim White, director of the Human Evolution Research Center at the University of California, Berkeley.

Read the full report here and note the assumptions that Lucy and Ardi are somehow less than human when the reserachers have concluded that these were human and not apes.

Important facts about Ardi and the Ardipithecus ramidus:

These 30+ skeletal finds represent the earliest known skeletons from the human family. The team found dozens of bones scattered over an area of 33 to 49 feet. The teeth to fit the range of human dentition and are not the dagger-like canines in male chimps and gorillas.

Paleoanthropologists are largely in agreement that the "Apes of the South" (Johanson's term for Lucy's community) were humans who lived about 3.2 million years ago. Ethiopian Ardi pushes that back about one million years. Lucy was found only about 45 miles from where Ardi was found. At the time these populations lived in east Africa it was forested, as was much of Africa. The bones were found in a stretch of the Awash River, near the village of Aramis in Ethiopia.

Ardi walked upright and stood on 2 legs. She shared food with others in her community. These remains reveal human dentition, not that of apes. It has taken 17 years for scientists to reconstruct and analyze these Ardipithecus ramidus findings which included the bones of no less than 35 individuals.

Paleoanthropologist Tim White led the University of California at Berkeley research team.

Physical evidence indicates that humans appeared as humans and unheralded by sub-human ancestors more than 4 million years ago. Apes do not share food or hunt cooperatively.


Georgia said...

Just have three questions...

How do they know their dating tests are accurate?

How did they know these ancient gals names?

GA said...

Whoops, that was just two...the third was another joke I thought better of and deleted (Were they wearing nametags?)

Alice C. Linsley said...

:) "Were they wearing nametags?"

They are now. All remains have been tagged and numbered.

"How do they know their dating tests are accurate?"

More than one dating system is used and together these provide a reasonable range of accuracy. The bones are found at a strata of earth that is dated by radiocarbon dating. Bones and teeth are tested by various techniques including DNA testing. Radiometric and DNA dating of human remains is reasonably accurate. Were the dating off by a 10% margin we would still be looking at millions of years.