Anthropologist Finds Explanation for Hominin Brain Evolution in Famous Fossils

ScienceDaily (May 7, 2012) — One of the world's most important fossils has a story to tell about the brain evolution of modern humans and their ancestors, according to Florida State University evolutionary anthropologist Dean Falk.

The Taung fossil -- the first australopithecine ever discovered -- has two significant features that were analyzed by Falk and a group of anthropological researchers. Their findings, which suggest brain evolution was a result of a complex set of interrelated dynamics in childbirth among new bipeds, were published May 7 in the Proceedings of the National Academy of Sciences.

"These findings are significant because they provide a highly plausible explanation as to why the hominin brain might grow larger and more complex," Falk said.

The first feature is a "persistent metopic suture," or unfused seam, in the frontal bone, which allows a baby's skull to be pliable during childbirth as it squeezes through the birth canal. In great apes -- gorillas, orangutans and chimpanzees -- the metopic suture closes shortly after birth. In humans, it does not fuse until around 2 years of age to accommodate rapid brain growth.

Read on:  http://www.sciencedaily.com/releases/2012/05/120507154025.htm