Posted on 11/11/2006 8:19:11 AM PST by Lessismore
Patrick D. Evans *, Nitzan Mekel-Bobrov *, Eric J. Vallender *, Richard R. Hudson , and Bruce T. Lahn *¶ *Howard Hughes Medical Institute, Departments of Human Genetics and Ecology and Evolution, and Committee on Genetics, University of Chicago, Chicago, IL 60637
Edited by Henry C. Harpending, University of Utah, Salt Lake City, UT, and approved October 5, 2006 (received for review August 10, 2006)
At the center of the debate on the emergence of modern humans and their spread throughout the globe is the question of whether archaic Homo lineages contributed to the modern human gene pool, and more importantly, whether such contributions impacted the evolutionary adaptation of our species. A major obstacle to answering this question is that low levels of admixture with archaic lineages are not expected to leave extensive traces in the modern human gene pool because of genetic drift. Loci that have undergone strong positive selection, however, offer a unique opportunity to identify low-level admixture with archaic lineages, provided that the introgressed archaic allele has risen to high frequency under positive selection. The gene microcephalin (MCPH1) regulates brain size during development and has experienced positive selection in the lineage leading to Homo sapiens. Within modern humans, a group of closely related haplotypes at this locus, known as haplogroup D, rose from a single copy 37,000 years ago and swept to exceptionally high frequency (70% worldwide today) because of positive selection. Here, we examine the origin of haplogroup D. By using the interhaplogroup divergence test, we show that haplogroup D likely originated from a lineage separated from modern humans 1.1 million years ago and introgressed into humans by 37,000 years ago. This finding supports the possibility of admixture between modern humans and archaic Homo populations (Neanderthals being one possibility). Furthermore, it buttresses the important notion that, through such adminture, our species has benefited evolutionarily by gaining new advantageous alleles. The interhaplogroup divergence test developed here may be broadly applicable to the detection of introgression at other loci in the human genome or in genomes of other species.
Pingski
An archaic Homo? I thought that they couldn't breed!
< /sarcasm >
Only if you believe in "evolution." Personally, I do not believe that I am related to, or a descendant from a monkey. Are these the same professional pointy heads that tried to get everyone to believe that oil was the product derived from dead and decaying dinosaurs?
Microcephalin gene? Does this result in pinheads?
This explains liberalism!
There are no scientists now, or ever, that have ever said oil is from dead dinosaurs.
They've said (accurately) for a long time that oil comes from fossil marine microscopic plankton (largely diatoms and algae.)
There has never been a scientific theory that oil comes from dinosaurs.
For whatever reason, people think there was for three reasons:
1) When you say, "fossil" people think "dinosaurs" though only a tiny, tiny, tiny portion of the fossils on earth are dinosaurs. And the average person has such limited scientific knowledge they don't know what a diatom or plankton is.
2) An oil company developed an amusing cartoon and billboard campaign linking oil to dinosaurs, which remained fixed in people's brains
3) A collection of idiots led by the moronic Jerome Corsi, in arguing for abiogenic oil, have created an imaginary strawman to argue against, that "scientists" claim oil is from "dinosaurs."
"from an archaic Homo"
Old homos are strange.
The dominant theory is that oil and coal come from plant matter, not dinosaurs.
Phytoplankton are technically plants, of course, but it's important to note again we're talking about plankton in water, not land plants (which forms coal.)
And like I said, there is not now, and never has been, a scientific theory that oil comes from dead dinosaurs.
Nothing like a good Neanderthal woman on a cold night.
Diggity
Look at a picture of a monkey or ape face, then look at a human. If you deny there is no similarity, there is no hope for you.
***2) An oil company developed an amusing cartoon and billboard campaign linking oil to dinosaurs, which remained fixed in people's brains***
ESSO or HUMBLE OIL.
So it sounds like 70% of us are descended from a single common ancestor who lived 37,000 years ago?
Our muzzi friends think we came from monkeys and pigs. Hmmm, maybe this ass is in the tank with them.
Haplogroup D is Japanese, Tibetans, Tajiks, and Andaman Islanders.
Scientists are trying to PROVE something they know can never be proved. It's the road to 'GRANTS FOREVER'.
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