Posted on 03/20/2008 10:58:20 AM PDT by blam
Skulls Of Modern Humans And Ancient Neanderthals Evolved Differently Because Of Chance, Not Natural Selection
The approximate locations of the cranial measurements used in the analyses are superimposed as red lines on lateral (A), anterior (B), and inferior (C) views of a human cranium. (Credit: National Academy of Sciences, PNAS (Copyright 2008))
ScienceDaily (Mar. 20, 2008) — New research led by UC Davis anthropologist Tim Weaver adds to the evidence that chance, rather than natural selection, best explains why the skulls of modern humans and ancient Neanderthals evolved differently. The findings may alter how anthropologists think about human evolution.
Weaver's study appears in the March 17 issue of the Proceedings of the National Academy of Sciences. It builds on findings from a study he and his colleagues published last year in the Journal of Human Evolution, in which the team compared cranial measurements of 2,524 modern human skulls and 20 Neanderthal specimens. The researchers concluded that random genetic change, or genetic drift, most likely account for the cranial differences.
In their new study, Weaver and his colleagues crunched their fossil data using sophisticated mathematical models -- and calculated that Neanderthals and modern humans split about 370,000 years ago. The estimate is very close to estimates derived by other researchers who have dated the split based on clues from ancient Neanderthal and modern-day human DNA sequences.
The close correlation of the two estimates -- one based on studying bones, one based on studying genes -- demonstrates that the fossil record and analyses of DNA sequences give a consistent picture of human evolution during this time period.
"A take-home message may be that we should reconsider the idea that all morphological (physical) changes are due to natural selection, and instead consider that some of them may be due to genetic drift," Weaver said. "This may have interesting implications for our understanding of human evolution."
Weaver conducted the research with Charles Roseman, an anthropologist at the University of Illinois at Urbana-Champaign, and Chris Stringer, a paleontologist at the Natural History Museum in London.
Adapted from materials provided by University of California, Davis.
I believe the Neandertals died out because their chicks were fugly.
The title was modified due to FR software requirements.
The Neandertal EnigmaFrayer's own reading of the record reveals a number of overlooked traits that clearly and specifically link the Neandertals to the Cro-Magnons. One such trait is the shape of the opening of the nerve canal in the lower jaw, a spot where dentists often give a pain-blocking injection. In many Neandertal, the upper portion of the opening is covered by a broad bony ridge, a curious feature also carried by a significant number of Cro-Magnons. But none of the alleged 'ancestors of us all' fossils from Africa have it, and it is extremely rare in modern people outside Europe." [pp 126-127]
by James Shreeve
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Thanks Blam. |
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What was it before?
It has to many words...
What he proposed was that Ancient Neanderthals were antediluviansAnother hypothetical construct offered by a person highly skilled
in the growth of skulls and teeth.
who lived approximately 900 years, hence the change in increase in
skull size and changes in teeth.
IBTF Placemarker
Oh, I see... doncha hate when that happens?
International Bikini Team Federation?
Expecting the creationists to come by to put their ignorance on full glorious display in 5...4...3...
Knock it off.
antediluvians? Does that mean they never took baths?
*sigh* Okay...
The word antediluvian (syn.Prediluvian) (Latin for "before the deluge") is used to describe a period of time that preceded the Great Flood of Noah as related in the Book of Genesis in the Bible.
I could have gone all day without that particular visual.
Oh sure, pile on. ;’)
You’ve got piles? TMI!
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