Brains show evolutionary designs
By Bruce Bower
Mammalian brains come in a variety of shapes, sizes, and organizations. Just how these neural disparities evolved remains mysterious.
Damon A. Clark of Princeton University and his colleagues are trying a new approach to this puzzle by comparing the proportions of nearly a dozen brain structures among many mammalian species. Like other related groups of species, mammals all share a basic arrangement of these structures. But in each species, these structures, as well as the overall brain, evolved to have specific sizes, the scientists report in the May 10 Nature.