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Euclides
Friday, July 9th, 2004, 12:45 AM
Proc Natl Acad Sci U S A. 2003 Jun 10;100(12):6926-9. Epub 2003 May 21. Related Articles, Links


The shape of the Neandertal femur is primarily the consequence of a hyperpolar body form.

Weaver TD.

Department of Anthropological Sciences, Stanford University, 450 Serra Mall, Building 360, Stanford, CA 94305-2117, USA. tweaver@stanford.edu

Neandertal femora are distinct from contemporaneous near-modern human femora. Traditionally, these contrasts in femoral shape have been explained as the result of the elevated activity levels and limited cultural abilities of Neandertals. More recently, however, researchers have realized that many of these femoral differences may be explained by the cold-adapted bodies of Neandertals vs. the warm-adapted bodies of near-modern humans. This study explicitly tests this proposed link between climate-induced body proportions and femoral shape by considering the entire hip as a unit by using geometric morphometric methods adapted to deal with articulated structures. Based on recent human patterns of variation, most contrasts in shape between the femora of Neandertals and near-modern humans seem to be secondary consequences of differences in climate-induced body proportions. These results, considered in light of hip mechanics during growth, highlight the importance of developmental and functional integration in determining skeletal form.

Agrippa
Friday, July 9th, 2004, 01:42 AM
Together with the other posts very good articles to discuss the Neandertal physical overspecialization vs. the modern sapiens mental-cultural and moderate physical specialization to the new climate.

morfrain_encilgar
Sunday, January 23rd, 2005, 03:01 AM
Together with the other posts very good articles to discuss the Neandertal physical overspecialization vs. the modern sapiens mental-cultural and moderate physical specialization to the new climate.

Early Upper Paleolithic modern Europeans had longer limbs thn neanderthals but were still adapted to a cool climate in their pelvis and femur, and at least some late neanderthals from the early Upper Paleolithic of Western Europe seem to be more in the direction of Early Upper Paleolithic moderns. This could be through adaptation to the climate, or else this could be because of mixing between populations.

SouthernBoy
Sunday, January 23rd, 2005, 05:00 AM
Together with the other posts very good articles to discuss the Neandertal physical overspecialization vs. the modern sapiens mental-cultural and moderate physical specialization to the new climate.
Is there such a thing as overspecialization? I thought specialization was the primary means by which populations evolve and speciate. :)

Dr. Solar Wolff
Sunday, January 23rd, 2005, 07:10 AM
Once I held a cast of a Neanderthal femur in my had. It was a real eye-opener. This thing was like the leg bone of a cow. It was so thick and the heads (ends) were so large as compared to a sapiens leg that it was simply stunning.

I think I have told this story to Atlanto-med and probably bored her to death but perhaps it is worth repeating in this context. Once, I did a study of human heel bones and bone density. It was a failure due to minerialization which we could not control for but had one interesting unexpected result. We found we could tell the sex on a individual by the volume. Two distinct groups formed within this population (American Indians) the difference was sex. I am sure this applies to other bones, especially the larger bones like the femur.

One Anthropologist came around whining that he wanted to be able to tell, for certain, if the Neanderthal femur was a male, even though we all knew it was. This was because only males, or alleged males as in this femur, had been found in certain Neanderthal stone cultures. The Neanderthal femur, in my mind, was outside the range of all sapiens in terms of volume and if enough Neanderthal femurs could have been found, I am sure they would have formed a seperate cluster, statistically, outside that of all sapiens in terms of volume.

What I am trying to say is that I don't think much of the study under consideration because the two hominids had radically different leg bones and no amount of confusion, using the hip, should be allowed to hide this fact.

morfrain_encilgar
Sunday, January 23rd, 2005, 12:14 PM
Is there such a thing as overspecialization? I thought specialization was the primary means by which populations evolve and speciate. :)

He means that adaptations to a certain location at a certain time, prevented them from adapting to new conditions later.