Oldest known human ancestor discovered.

Researchers in Ethiopia have discovered the oldest-known human ancestor. The partial skeleton, a female Ardipithecus ramidus nicknamed “Ardi,” is the oldest known hominid, dating to about 4.4 million years ago.

The closest modern human relative, the Chimpanzee, is thought to have diverged genetic lines with humans some 6 to 7 million years ago, which suggests that while Ardi is an astounding find, she is not the missing link. This fact has been stressed by researchers.

“Ardi” is clearly a human ancestor and her descendants did not grow up to be chimpanzees or other apes, the researchers report in the journal Science.

She had an ape-like head and opposable toes that allowed her to climb trees easily, but her hands, wrists and pelvis show she strode like a modern human and did not knuckle-walk like a chimp or a gorilla.

“People have sort of assumed that modern chimpanzees haven’t evolved very much, that the last common ancestor was more or less like a chimpanzee and that it’s been … the human lineage … that’s done all the evolving,” White said.

But “Ardi” is “even more primitive than a chimpanzee,” White said.

Ardi is about a million years older than Lucy, a female Australopithecus afarensis who represents the best-known human ancestor.