Sapiens Sapiens Evidence Evidence

October 19, 2007

Two new pieces of evidence were announced this week that should shed some light on hominid evolution. First, researchers at Arizona State University have shown that anatomically modern humans exhibited advanced behaviors earlier than expected.

“Our findings show that at 164,000 years ago in coastal South Africa humans expanded their diet to include shellfish and other marine resources, perhaps as a response to harsh environmental conditions,” notes Marean, a professor in ASU’s School of Human Evolution and Social Change. “This is the earliest dated observation of this behavior.”

Further, the researchers report that co-occurring with this diet expansion is a very early use of pigment, likely for symbolic behavior, as well as the use of bladelet stone tool technology, previously dating to 70,000 years ago.

There is a boundary between “anatomically modern humans” (Homo sapiens) and the modern humans that left Africa approximately 50,000 years ago (Homo sapiens sapiens). The question is whether there was a true speciation event at this boundary or whether there was simply a kind of cultural renaissance.

Those that support the idea of a speciation event believe that a change in the brain accounts for the difference and that the most likely brain change involved language.

The second major piece of evidence may rule out the language theory. The analysis of Neanderthal DNA has shown that Neanderthals possessed the same FOXP2 gene as modern humans (i.e. us).

Neanderthals, an archaic human species that dominated Europe until the arrival of modern humans some 45,000 years ago, possessed a critical gene known to underlie speech, according to DNA evidence retrieved from two individuals excavated from El Sidron, a cave in northern Spain.

The new evidence stems from analysis of a gene called FOXP2 which is associated with language. The human version of the gene differs at two critical points from the chimpanzee version, suggesting that these two changes have something to do with the fact that people can speak and chimps cannot.

So that really throws a wrench in things. If the modern FOXP2 gene is an accurate test for advanced language then everyone and their sister with an over-sized brow had language. Perhaps another change independent of language occurred that can account for the explosion of advanced behavior in Homo sapien sapien 50,000 years ago or maybe we should send the “sapiens sapiens” name back to the department of redundancy department.

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