2 posts tagged with biology by Jason Malloy.
Displaying 1 through 2 of 2.
Neanderthal Lovin’! New research from evolutionary scientist Bruce Lahn suggests that humans and the now extinct Neanderthal species mixed, and humans snatched up a valuable brain gene in the process. (The gene, MCPH1, and Lahn, discussed last year on MeFi) This comes on the tails of yet another new study providing morphological evidence that there was nontrivial interbreeding between humans and Neanderthals in Eurasia, despite the fact that Neanderthals may have been genetically closer to chimps than humans. Contrary to popular imagination, though, the Neanderthal species had bigger brains and sophisticated intellects, at least roughly on par with that of human beings. The gene regulates brain size during development, but its exact utility to humans is still unknown (and controversial). The origin of this gene and the question of Neanderthal mixing will soon be answered more definitively by the, just launched, 2 year project to map the Neanderthal genome, headed by Svante Pääbo (profiled in recent Smithsonian and Wired articles). Pääbo calls Lahn’s study "the most compelling case to date for a genetic contribution of Neandertals to modern humans."
Genes Reveal Recent Human Brain Evolution. Two important new papers in the journal Science (available here) from the evolutionary geneticist and rising star, Bruce T. Lahn (see this recent profile from The Scientist), are potentially the tips of some very large icebergs. The papers document how two genes related to brain properties that underwent strong selection during the course of hominid evolution, have continued undergoing strong selection since the emergence of anatomically modern man. The papers wonderfully illustrate how biological evolution is an ongoing process as well as the artificial distinction between “micro” and “macro” evolution, and promise to be controversial for two reasons: First, the brain genes underwent the strongest selection during two periods of cultural and technological efflorescence (roughly 37,000 and 5,800 years ago). Second, the genes are distributed very differently in modern human population groups, existing at very high frequencies in some groups and being very rare in others, ensuring that the modern function of these genes will be a source of more research and much impassioned debate. More observations from anthropologist John Hawks.