May 06, 2005

Neanderthal femur from France

In a new paper, researchers report on a recently discovered Neanderthal femur from France. Part of the mitochondrial sequence was retrieved, and it matches other ancient Neanderthal specimens in having specific substitutions which are lacking in modern humans.

I often wonder why the study of ancient DNA from Neanderthals seems to be proceeding at a fast pace, but with the exception of two Italian Cro-Magnons there seem to be little published research on modern humans of Pleistocene age. These two specimens were similar to modern humans genetically and different from Neanderthals, but it is possible that other ancient specimens may turn out to be more similar to Neanderthals, or even completely different. This might signify that human mtDNA has changed over the ages due to selection, which has eliminated some mtDNA clades in favor of others which survive today. If that turns to be true, then the distinctiveness of Neanderthal mtDNA compared to modern humans may be due to its antiquity, and not because Neanderthals belonged to a different species.

Proc. Natl. Acad. Sci. USA
(Published Online)

A late Neandertal femur from Les Rochers-de-Villeneuve, France

Cédric Beauval et al.

In 2002, a Neandertal partial femoral diaphysis was discovered at Les Rochers-de-Villeneuve (Vienne, France). Radiocarbon dated to {approx}40,700 14C years before present, this specimen is one of the most recent Middle Paleolithic Neandertals. The diaphysis derives from an archeological level indicating alternating human and carnivore (mostly hyena) occupation of the cave, reinforcing the close proximity and probable competition of Middle Paleolithic humans with large carnivores for resources and space. Morphological aspects of the diaphysis and ancient DNA extracted from it indicate that it is aligned with the Neandertals and is distinct from early modern humans. However, its midshaft cortical bone distribution places it between other Middle Paleolithic Neandertals and the Châtelperronian Neandertal from La Roche-à-Pierrot, supporting a pattern of changing mobility patterns among late Middle Paleolithic Neandertals on the eve of modern human dispersals into Europe.


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