ScienceShot: A Complex Brain Inside a Very Big Skull

Elephants are famous for having a good memory, but they also have complex communication skills and rich social lives. Unfortunately, scientists know virtually nothing about the 5-kilogram brain responsible for these talents. This week, in a presentation at the annual meeting of the Society for Neuroscience and in a paper in Brain Structure and Function, scientists present the first microscopic study of neurons in the cerebral cortex of the African elephant. The cortex is the thin layer of cells on the surface of the brain that governs many functions, and in elephants it contains a greater variety of cell types (such as the extensively branched neuron pictured above) than is found in more frequently studied animals such as rodents and primates. How this complexity contributes to an elephant's smarts isn't known, but the authors say their findings suggest that evolution has found multiple ways to build a complex brain—and an intelligent beast.