Frans de Waal has studied the behavior of primates for five decades. Some of his many important observations center around the evolution of morality and just how much we have in common with the animal kingdom.

The idea that animals are always in conflict with one another and competing for resources is “totally wrong,” de Waal says. 

Other primates, specifically chimpanzees and bonobos, have demonstrated a range of traits and tendencies typically regarded as human, including empathy, friendship, reconciliation, altruism, and even adoption.

FRANS DE WAAL: People sometimes describe nature as a dog-eat-dog world. Some of the biologists depict nature as a battlefield basically where selfish tendencies tend to prevail. And from morality, the evolution of morality there's very little room. What they mean is that all they see is competition. I win, you lose, winning is better than losing and so on. That's totally wrong. I fought against that sort of characterization of animal society all my life, because just like human society it is built on a lot of friendship and cooperation at the same time. We'd like to deny that connection that exists between us and animals. Certain tendencies, such as a sense of fairness, empathy, caring for others, helping others, following rules, punishing individuals who don't follow the rules, all of these tendencies can be observed in other primates. And they're saying these are the ingredients that we use to build a moral society.

The whole spectrum of both very positive behavior and very negative behavior can be seen in other animals. Animals can be heroic and they can be genuinely altruistic and we actively tested in our chimpanzees. We've done an experiment where a chimpanzee can choose between two options. One option rewards only himself, the other option rewards himself plus a partner who sits next to him. And our chimpanzees preferred the latter option. They prefer a task where they can reward the partner at the same time as themselves. The primates are a very cooperative society in general. The reason they live in groups is that on their own they cannot survive. So they have to have companions from whom they get support, with whom they live together, who help them find food, who warn them against predators. And they have long-term friendships in their society just like humans have. There's a lot of studies on how animals do favors for each other. And if you think about how this works it has to be based on gratitude. Like you do something for me, and I do something back to you. There must be some sort of emotional mechanism in there. And there's descriptions in the wild of people who, for example, who cut loose a whale who has been caught in a net, and they describe how the whale doesn't just swim away. The whale goes back to all these people and nuzzles them or lifts them up out of the water, and then he disappears, and they feel the whale is expressing his gratitude for whatever happened. So there's all sorts of signs that animals have that capacity.

In the '70s I discovered that chimpanzees reconcile after fights. Many animals have this process where a relationship is disturbed by fighting, but the relationship is still valuable to you, so you need to do something about what happened to it. When I saw in the chimpanzees that they sometimes kiss and embrace each other after fights, and later in bonobos, I saw that they have sex after fights. I immediately understood that reconciliation is common and then later of course, many other studies have found reconciliation not just in the primates, in elephants and dolphins, in wolves, in goats. And adoption is also typical. So for example, in Tai forest, in Ivory Coast, there is a documentation of 10 cases of adoption by males, adult males, who have adopted an orphaned chimpanzee. So the chimpanzee loses its mother, chimpanzees are dependent on their mother for at least eight years of their life. So if you lose your mother at three years of age, you may be able to survive on solid food, but you still need to be carried and protected. And someone needs to explain to you what to eat and what not to eat. And adult males are willing to do that. And so they spend an enormous amount of time and energy into individuals that they don't get much back from. And I find that very interesting cases, these cases of altruism that don't fit any evolutionary scenario but nevertheless occurred.

And so we look at prosocial tendencies and helping behavior, and animals can be truly altruistic, and I'm convinced of that. But animals can also of course be very mean to each other. Chimpanzees, for example, they are known in the field sometimes to kill their neighbors because chimpanzees are very hostile and very xenophobic. If they see strangers, they have very different reactions to them than when they see their familial members. For example, familial group members they have empathic reactions and we can test that in particular ways, but with strangers they certainly don't have that. So chimpanzees are very good model of tribal humans so to speak, but we have an equally close relative which is the bonobo, exactly as close to us as the chimp. And bonobos ,when the groups meet in the wild instead of killing each other the way chimpanzees will do, they mingle, they have sex, they groom each other. It looks more like a picnic than warfare between them. The bonobos has been called xenophilic meaning is actually attracted to strangers and has positive contacts with them.

In my work I sometimes contrast anthropomorphism as anthropodenial. Anthropomorphism is when we put, let's say, too much human characteristic into an animal. And that's of course not good. But anthropodenial is also not good where we sort of deny the connection that we have with animals. And the fact that we are animals. I look at humans basically as primates. 95% of what we do are primate tendencies and primate emotions and primate sociality. And there is a certain part that is uniquely human, obviously, for example, I'm talking here to a TV screen which is pretty unique I would say, but still I'm communicating and making facial expressions and gestures, I'm communicating, there's an audience, which is a very primate thing to do. And so we have this very interesting combination of our cultural and technical achievements, with our old primate heritage. But I always look more at the primate heritage than anything else.