A Map of the Dolphin Mind

Fifteen years ago, the dolphin brain got no respect. Despite dolphins’ obvious intelligence and social aptitude, anatomical studies of their gray matter revealed an indistinct muddle of neurons, nothing like the specialized, refined structures found in human brains. The animals lack a layer of neurons considered essential to information processing, and many parts of their brains—especially the frontal lobe, the site of higher cognition in people—looked underdeveloped.