Thursday, July 15, 2010

Fossils May Reveal When Humanity's Ape Ancestors Split from Monkeys

fossilsFossils unveiled on Wednesday reveal that the last ancestor shared by monkeys and humans lived most likely between 24 and 28 million years ago, which is several million years later than previously assumed.

A partial skull of an unknown species was found in western Saudi Arabia that rewrites the timeline of primate evolution and fills in a vast gap in the fossil record, researchers said.

Previous genome-based analysis put the split between hominoids (apes and humans) and cercopithecoids (Old World monkeys) at 35 to 30 million years ago.

But now, the new species, dubbed Saadanius hijazensis, has been precisely dated to nearly 28 million years ago, and may have endured even longer before the split occurred.

The unique features of the fragment show that the last common ancestor of monkeys, apes and humans existed further up the evolutionary tree than the genetic approach had originally suggested.

The new discovery makes it possible for scientists, for the first time, to identify the mysterious fossil of another primate that lived four million years later as clearly belonging to a post-split ape.

Full story here.

No comments: