Animal Brainiacs: The World's Smartest Animals

3. Dolphins

If size matters, then dolphins are geniuses; their brains, as a percentage of their body mass, are among the biggest on the planet. They are the only non-human creatures that seem to have individual names that they choose themselves. Even more interestingly, dolphins understand much about us — including gestural language, pictures, and emotions — and yet we don’t really know much about them. Fifty years of research still can’t decode their communications of clicks and whistles or understand how their giant brains work.