Consider two different, but similar situations. In the first, children are asked to pull ropes together. Candy cascades down, but in unequal distribution – three for one child and one for the other. In the second situation, the children come across the sweets but without joint labor, and again find an uneven distribution.

What usually happens next differs between the two situations. When the kids work together, they tend to willingly share the proceeds so everyone ends up with an equal share. But when the candy was discovered through individual serendipity, the children tend to accept the uneven outcome and don’t equalize shares.

The first situation involves what Mike Tomasello, the James F. Bonk Distinguished Professor of Psychology at Duke University, would call joint commitment; “When children produce sweets collaboratively they feel they should share them equally.” There’s no explicit promise of an equal share, but there is an implicit one that’s just as recognizable and genuine.

As Tomasello details to interviewer David Edmonds in this Social Science Bites podcast, “I can say I don’t like it when you keep all the sweets – that’s my personal opinion – but when I say ‘you shouldn’t do that, you mustn’t do that, you must do this, you have to do that,’ this is not my personal opinion. This is something objective.”

While this might be a normative bond that helps glue humans together, it’s not a bond he finds in our closest relatives. Tomasello points out that among chimps – with which the longtime co-director of the Max Planck Institute for Evolutionary Anthropology has a deep background researching - the dominant partner takes the spoils in almost all cases. The “we-ness” that can mark human behavior is replaced by the “me-ness” of other primates.

That difference between primates and people is the basis of much of Tomasello’s career (see the work of the Tomasello Lab at Duke: “studying the development and evolution of social cognition, communication, and cooperation“) and of his 2018 book, Becoming Human: A Theory of Ontogeny. Much of his effort has focused on great apes, our closest primate relatives, following a line of research that started with Jane Goodall learning that apes make and use tools. Great apes share many qualities with human beings – they understand causal relations, can work with the concept of quantities, can predict what others might do based on what they see and what their goal is, are good social learners, can communicate with gestures (and can learn new ones), and can work with one another in some cases.

But Tomasello notes a key area in which apes and people differ. “Humans put their heads together, as a general phrase, to accomplish things that neither one can do on his or her own. So if you look at all the things you think are most amazing about humans – we’re building skyscrapers, we have social institutions like governments, we have linguistic symbols, we have math symbols, we have all these things – not one of them is the product of a single mind. These are things that were invented collaboratively at the moment or else over time as individuals build on one another’s accomplishments.”

Great apes and other creatures – ants and bees do offer a limited counter-example -- don’t do that. Understanding this evolved capacity – Tomasello doesn’t like using terms like “hard-wired” or “innate” – isn’t just a matter for academic interest. While he shied away from talking about the normative implications of his research and theories, Tomasello noted the benefits of cooperation and collaboration (and also some of its less-welcome artefacts such as creating out-groups to discriminate against), whether in sports, or work, or society. While he wouldn’t develop public policies, “If you want a more cooperative society, I can tell you some things that would help.”