Some of the theories still face strong resistance.

For over 40 years, primatologist Frans de Waal has been debunking myths about differences between animals and humans. Animals emotions have long been ignored. But he says our emotions are more similar than we think — beginning with empathy. Studies show that primates have a similar sense of fairness. He believes the roots of morality are seen in the social behavior of monkeys and apes.

“What we should learn is that we are primates, we are not different really, we have bigger brains, we have no different brains. There's nothing in our brain that is not in a chimpanzee brain. Our need for social relationships, our need for affection and love, our ways of we resolve conflict between each other, all these things are extremely similar. The chimpanzee communicates all these shades of emotion that we have but we don't always see that. I noticed that for example chimpanzees have one chimpanzee has lost a fight, others will go over and embrace them and kiss them and try to calm them down. People didn't want to hear about empathy in animals. If animals kill each other we want to hear about that, because that's what animals are supposed to do, but empathy was not part of the concept that people had about animals.”

His research into the innate capacity for empathy among primates has led De Waal to the conclusion that non-human great apes and humans are simply different types of apes, and that empathic and cooperative tendencies are continuous between these species. The idea behind the animal origins of human characteristics was introduced by Charles Darwin in 1872. Some of the theories still face strong resistance. Often criticized for “anthropomorphism” — the attribution of human characteristics to animals — de Waal has shed light on the negative effects of denying this — or “anthropodenial.”

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