Biologists have studied animal intelligence for years, but primatologist Frans de Waal believes we underestimate exactly how smart they are. He believes humans tend to observe animal behavior with their own exceptionalism in mind. He bridges the dividing line between humans and animals in his new book "Are We Smart Enough to Know How Smart Animals Are?

"We have simplified animals far too much... There are so many capacities in the animal kingdom that we do not know at all," primatologist and Emory University professor Frans de Waal on human understanding of animal intelligence.

We speak with de Waal about his research into the evolution of animal intelligence.