Found: The Genes Behind Big Human Brains

Human brains are three times bigger than those of our ancestors. Researchers behind a pair of new studies think they've found the genes responsible. (Credit Fiddes et al) With a new pair of studies on a handful of genes unique to the genus Homo, researchers took a big step toward solving one of the most important questions about our evolution — why and how human brains got so big. Understanding why the Homo brain became significantly larger than the gray matter of any other primate has been a dominant question in the field ever since we first turned our big human brains toward the topic of evolution. In just the last week, separate teams of researchers have released models for the environmental conditions that may have driven our ancestors' brains to triple in size over the past 3-4 million years. Based on different mathematical models, one team concluded ecological challenges ...