Apes, Old World Monkeys May Have Split Later Than Thought

[Ignis]

A slope-faced, big-toothed creature from the distant past has inspired scientists to recalibrate the ancient evolutionary split between apes and Old World monkeys.

sciencenewsDiscoverers of a partial apelike skull in western Saudi Arabia say that it now appears that a poorly understood parting of major primate groups occurred between 29 million and 24 million years ago. A 2004 analysis of DNA from living apes and monkeys in Africa and Asia had estimated an earlier divergence, between 34.5 and 29.2 million years ago.

An intriguing mosaic of features on the newly unearthed fossil, which dates to between 29 million and 28 million years ago, suggests that it lived shortly before a common ancestor that gave rise to hominoids — a primate lineage that includes apes and humans — and the monkeys of Africa, Asia and Europe. A team led by anthropology graduate student Iyad Zalmout of the University of Michigan in Ann Arbor reports the find in the July 15 Nature.
(...snip...)
But a few critical anatomical features, including a long, tube-shaped ear canal, distinguish Saadanius from its primate predecessors, the scientists say. And unlike Old World monkeys and hominoids that evolved after about 24 million years ago, Saadanius — which Zalmout’s group identifies as a male based on dental characteristics — lacked nasal sinuses and large canine teeth typical of later ape and monkey males.

For that reason, the researchers use 24 million years as the most recent estimate of when Old World monkeys diverged from apes.

-- Wired @ http://www.wired.com/wiredscience/2010/07/ape-monkey-split/

This is really interesting to those who follow hominid ancestry in physical anthropology. The shift in this date of divergence needs more data, of course, but the fossil does fit into the record in the way it "should." It will be interesting to see how researchers will use this new divergence date to re-examine existing DNA evidence from monkeys and apes.

[Judi Lynn]

1. Thanks for the info. Interesting. Hope more will follow soon.

:kick: :kick: :kick: :kick:

[Ignis]

2. Thanks, Judi.

I'm proud to be posting my first OP in the Judi Lynn forum.

:hide:

I kid! I kid! :D Thanks for all the great links.

[Judi Lynn]

3. When I started posting things here it was the L. Coyote forum, with fascinating material.

A look through earlier posts will provide some great reading!