Literature

In 1998, Ian Tattersall wrote: "All of which brings us back to the question of whether Neanderthals had language. To which the answer is almost certainly no, at least in the form in which we are familiar with it." (Becoming Human: Evolution and Human Uniqueness, p172). He provided many other arguments to justify the conclusion that Neanderthals are really different from humans. However, in the following years, archaeological finds have chipped away at this position and today Neanderthals look a lot more like humans than they appeared then. But disputes continue over language.
A genetic link with language has been identified. "So the speculation was that [the FOXP2 variations] were unique to humans and not there in Neandertals," says evolutionary geneticist Svante Paabo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who traced FOXP2's ancestry. "If there was one single gene I really wanted to see in Neandertals, it was this one." Culotta writes:

"Paabo appears to have gotten his wish: His team extracted ancient DNA from two 43,000-year-old Neandertal bones found in a cave in northern Spain. Genetic analysis revealed that the FOXP2 sequence in both Neandertals matched that in living people. It harbored the two mutations that help set the human gene apart from those of all other animals. This doesn't necessarily prove that Neandertals could speak, because many other, unknown genes probably influence language ability. But "with respect to FOXP2, there's nothing to say that Neandertals could not speak just like we do," says Paabo. He now suggests that the gene was favored by selection much earlier, before Neandertals and modern humans had completely diverged, perhaps 300,000 or 400,000 years ago."

The recent controversy over the issue of contamination is one the authors claim to have addressed. Allowing that the genetic link is only one element of the language question, this new evidence can be used to trigger an alternative hypothesis about Neanderthals. Instead of a common ancestor of humans and Neanderthals, another possible hypothesis is that Neanderthals is a descendant species of humanity. They buried their dead and had a variety of aesthetic practices because they were human. They spoke because they were human. Surely we have now reached the stage where this hypothesis can be tested alongside evolutionary options?

The Derived FOXP2 Variant of Modern Humans Was Shared with Neandertals
Johannes Krause, Carles Lalueza-Fox, Ludovic Orlando, Wolfgang Enard, Richard E. Green, Hernan A. Burbano, Jean-Jacques Hublin, Catherine Hanni, Javier Fortea, Marco de la Rasilla, Jaume Bertranpetit, Antonio Rosas, and Svante Paabo.
Current Biology, online October 18 2007 | doi 10.1016/j.cub.2007.10.008

Summary: Although many animals communicate vocally, no extant creature rivals modern humans in language ability. Therefore, knowing when and under what evolutionary pressures our capacity for language evolved is of great interest. Here, we find that our closest extinct relatives, the Neandertals, share with modern humans two evolutionary changes in FOXP2, a gene that has been implicated in the development of speech and language. We furthermore find that in Neandertals, these changes lie on the common modern human haplotype, which previously was shown to have been subject to a selective sweep. These results suggest that these genetic changes and the selective sweep predate the common ancestor (which existed about 300,000-400,000 years ago) of modern human and Neandertal populations. This is in contrast to more recent age estimates of the selective sweep based on extant human diversity data. Thus, these results illustrate the usefulness of retrieving direct genetic information from ancient remains for understanding recent human evolution.

See also:

Culotta, E. Talk Like a Man, ScienceNOW Daily News, 18 October 2007