DOLPHINS: SECOND-SMARTEST ANIMALS?

When human measures for intelligence are applied to other species, dolphins come in just behind humans in brainpower, according to new research. Dolphins demonstrate skills and awareness previously thought to be present only in humans.

New MRI scans show that dolphin brains are four to five times larger for their body size when compared to another animal of similar size, according to Lori Marino, a senior lecturer in neuroscience and behavioral biology at Emory University, and one of the world's leading dolphin experts. Humans also possess an impressive brain-to-body ratio.