Posted on 08/31/2005 11:35:50 AM PDT by PatrickHenry
Palaeontologists digging in the dusty wastelands of East Africa have discovered the first known chimpanzee fossil. The modest haul of just three teeth is the first hard evidence of the evolutionary path that led to today's chimpanzees.
As well as shedding light on chimps, the find throws up new questions about human evolution; it seems that chimpanzees may not have been physically separated from humans as was once thought.
That no one had previously found a chimpanzee fossil had long been a frustrating puzzle, comments Sally McBrearty, an anthropologist at the University of Connecticut, who made the find near Lake Baringo, Kenya, with her colleague Nina Jablonski. Set against the many human fossils found in East Africa, the lack of specimens documenting the chimp's evolutionary story was exasperating.
Part of the problem, McBrearty explains, is that chimps tend to live in hot, wet jungle conditions that are not good for the preservation of remains. Humans, on the other hand, are thought to have lived for millennia on the savannah, where bones are less likely to rot.
The great divide
Previous theories suggested that chimps never crossed east of the Rift Valley, but instead stayed in the jungles of western and central Africa. Some even suspected that this physical separation was what set the earliest chimp and human ancestors on contrasting evolutionary voyages. But now McBrearty has stumbled on chimp remains east of this divide.
This means we need a better explanation of why and how chimps and humans went their separate evolutionary ways, McBrearty says. The discovery that chimps were living in semi-arid conditions as well as in the jungle seems to blow apart the simplistic idea that it was the shift to savannah that led to humans walking upright.
The teeth are around 500,000 years old, McBrearty and Jablonski report in Nature1. So far it is impossible to say whether they belonged to the same species as modern chimps, Pan troglodytes, or to some unnamed, now extinct ancestor. "It wouldn't surprise me if there are lots of extinct chimp species," McBrearty says.
If the teeth do belong to the same species as modern chimps, this would mean the species is quite long-lived. In contrast, modern Homo sapiens has been around for only some 200,000 years. But the earlier human species H. erectus is thought to have lasted around a million years.
Finding the ancestor
The fossils are not old enough to tell us about the common ancestor of chimps and humans, which lived between five and seven million years ago, points out anthropologist Daniel Lieberman of Harvard University in Cambridge, Massachusetts. "But this raises hope that we can find older stuff," he adds.
McBrearty suspects that although there may have been more chimps living in the jungles of western Africa, there are probably more fossils in the dry eastern savannah. It's just that "no one was looking for them" she says.
McBrearty hopes to return to Kenya in December to resume the search. In spite of the baking equatorial heat, December's dryness makes it the best time to probe for delicate remains.
Thank you.
Maybe it mutated and evolved into another species of ping. Perhaps by a virus or spyware.
......;^) (/pro-evo satire)
Cheeta the Chimp says "Ooga, Ooga!"
Sure. Your example is good. This chimp could have been brought from far away as somebody's pet for all we know.
By what method were the teeth dated?
Article doesn't say.
I presume, they were dated by the surrounding strata.
Not enough material for lab testing?
Bipedalism occured at least 4 million years ago. It's a simplistic idea to suggest that a chimp passing through 3 1/2 million years later somehow blows away the "shift to savannah" hypothesis!
Ceasar was supposed to overthrow the humans in 1991. Were over due!!
1. Fossil of first chimp, orGotta get that adjective first positioned next to its noun, with no room for misinterpretation.
2. First fossil of chimp.
I bet you burned out your PhotoShop with this one, LOL!
Thanks for adding to my browser's "block images from" list.
Helen hasn't looked that good in 500,000 years.
1. Fossil of first chimp, or
2. First fossil of chimp.
Neither. It is unlikely that this specimen was the first chimp, or the first chimp to be fossilized, but it is the first fossilized chimp to be found. Door number 3, Monty:
3. First discovery of a fossilized chimp.
Well, it's only an adverb.
Only, well, it's an adverb.
It's only a well adverb.
It's only an adverb well.
Only, it's an adverb well.
Only, it's a well adverb.
Man-eating shark killed.
Man eating shark killed.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.