Genes Reveal Recent Human Brain Evolution.
Two important new papers
in the journal Science
) 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.
posted by Jason Malloy
on Sep 8, 2005 -