Into Africa? Fossils suggest earliest anthropoids colonized Africa

[DavidDvorkin]

Today in the journal Nature, a new discovery described by a team of international scientists, including Carnegie Museum of Natural History paleontologist Christopher Beard, suggests that anthropoids—the primate group that includes humans, apes, and monkeys—"colonized" Africa, rather than originally evolving in Africa as has been widely accepted. According to this paper, what is exceptional about these new fossils—discovered at the Dur At-Talah escarpment in central Libya—is the diversity of species present: the site includes three distinct families of anthropoid primates that lived in North Africa at approximately the same time.

This suggests that anthropoids underwent diversification, through evolution, previous to the time of these newly discovered fossils, which date to 39 million years ago. The sudden appearance in the African fossil record of diverse anthropoid families can be answered in one of two ways, the paper's authors say. It could be the result of a striking gap in the African fossil record prior to this period. This is unlikely to be the case as Northern Africa's Eocene sites have been well sampled over the past century, and no diversity of anthropoid fossils has yet been discovered that predates the new Libyan specimens. Therefore, the paleontologists suggest, it is more likely that several anthropoid species "colonized" Africa from another continent 39 million years ago—the middle of the Eocene epoch. Since diversification would have occurred over extreme lengths of time, and likely leave fossil evidence, the new fossils combined with previous sampling in North Africa leads the paper's authors to surmise an Asian origin for anthropoids, as proposed by Beard and his colleagues in earlier work, rather than a gap in the fossil record.

http://www.eurekalert.org/pub_releases/2010-10/cmon-iaf102510.php

[DavidDvorkin]

1. I assume this doesn't undermine the standard picture

Olduvai Gorge, etc. Our ancient ancestors, I guess, migrated down the continent, and then the evolution to human took place as already established.

[Viva_La_Revolution]

2. more details from ScienceDaily..

http://www.sciencedaily.com/releases/2009/09/090915101355.htm
In Egypt, the presence of more than a dozen fossilized anthropoid primates dating from 30 to 38 million years ago had long been known. This recent Franco-Algerian discovery thus advances the first true appearance of anthropoid primates on the African continent by more than 15 million years. With its major consequences on the evolutionary history of African anthropoid primates, this observation further strengthens the alternative hypothesis of an Asiatic origin for anthropoids. Furthermore, this paleontologic research reveals a hitherto unsuspected diversity and great antiquity of the first crown strepsirhines in Africa.


so.. you are correct. :)

on edit: another find in Myanmar 2009..

New Fossil Primate Suggests Common Asian Ancestor, Challenges Primates Such As 'Ida'

ScienceDaily (July 1, 2009) — A new fossil primate from Myanmar (previously known as Burma) suggests that the common ancestor of humans, monkeys and apes evolved from primates in Asia, not Africa as many researchers believe.
http://www.sciencedaily.com/releases/2009/06/090630202125.htm

[starroute]

5. Not quite -- there are also gaps in the later picture

In particular, it isn't clear when or how the transition from the Australopithecines to Homo erectus took place.

The 1.8 million year old skulls found in former Soviet Georgia -- which range from very Australopithecine-like to fully evolved Homo erectus -- suggest the transition may have taken place there or somewhere nearby. http://news.bbc.co.uk/2/hi/science/nature/2645183.stm

The earliest dates for Africa also cluster around 1.7 or 1.8 million years ago, but there Homo erectus appears in the fossil record suddenly, with no transitional forms.

In addition, China claims to have Homo erectus tools and remains that are 1.7 million years old or more. Those in Malaysia and Java also date to 1.7 or 1.8 million years ago. Even a recent French find is dated at 1.57 million years ago.

So although there is still no definite conclusion, evidence is piling up that Homo erectus evolved somewhere in Asia before returning to Africa to undergo the further evolutionary leaps that led to our own ancestors.

[Kurt_and_Hunter]

3. Reasonable enough

I don't think anyone believes life first emerged on land in central western Africa so our ancestors traveled there at some point along the line.

If it was at the anthropoid level then that's what it was.

[Xithras]

4. Every species comes from everywhere, if you go back far enough.

Technically, all mammals appear to be descended from Hadrocodium, which evolved in Sinemurian Asia (present-day Yunnan Province, China, to be exact).

[muriel_volestrangler]

6. You can't be that precise

Hadrocodium may be the earliest animal yet found with certain mammal features, but it's still possible that all mammals are actually descended from an as-yet-undiscovered 'sibling' species, and that those mammalian features first developed in another as-yet-undiscovered ancestor of them both.