Where does our tendency to cooperate come from? Is it natural for us to cooperate or is it the result of social learning? It’s tempting to think that we’re born as non-cooperative beasts that need to be tamed via education and other forms of cultural learning. The whole idea of ‘human civilization’ revolves around the assumption that humans have somehow risen above animals because they can cooperate, have morals and be kind to one another.But even a casual look at nature will convince you that cooperation is not exclusive to humans. Chimpanzees cooperate, bees cooperate, wolves cooperate, birds cooperate, ants cooperate… the list goes on and on. There are myriad species in nature that cooperate with their conspecifics.This leads one to think that cooperation in humans must also have its roots in natural selection- that cooperation may not be entirely the result of cultural conditioning but something that we’re born with.Evolution of cooperationCooperation is usually a good thing for species to possess because it enables them to do things efficiently. What an individual cannot do by itself a group can. If you’ve ever observed ants carefully you must’ve seen how they share the load of a particularly heavy grain that a single ant couldn’t possibly carry.Tiny yet fascinating! Ants building a bridge out of themselves to help others cross over.In us humans too, cooperation is something that should be favoured by natural selection because it’s beneficial. By cooperating humans can better their chances of survival and reproduction. Individuals who cooperate are more likely to pass on their genes.But there’s a flipside to the story. Individuals who cheat and don’t cooperate are also more likely to be reproductively successful. Individuals who receive all the benefits a group provides but don’t contribute anything have an evolutionary advantage over those who do cooperate. Such individuals lay their hands on more resources and hardly incur any costs. Since the availability of resources can be correlated with reproductive success, over evolutionary time, the number of cheaters in a population must increase.The only way in which the evolution of cooperation can happen is if humans have the psychological mechanisms to detect, avoid and punish cheaters. If cooperators can detect cheaters and interact with only like-minded cooperators, cooperation and reciprocal altruism can gain a toehold and evolve over time.Psychological mechanisms favouring cooperationIf you pause to think about all psychological mechanisms that we possess to detect and avoid cheaters, you’ll soon realize that a rather great part of our psyche is devoted to these ends.We have the ability to recognize many different individuals, not just by their names but also by the way they talk, walk and the sound of their voice. Identifying many different individuals helps us identify who is cooperative and who is non-cooperative.No sooner do new people meet than they form quick judgments about each other, mostly about how cooperative or non-cooperative they’re going to be.“She’s nice and very helping.” “He has a kind heart.”“She’s selfish.”“He’s not the type who shares his stuff.”Similarly, we have the ability to remember our past interactions with different people. If someone deceives us, we tend to remember this event vividly and vow never to trust that person again or demand an apology. Those who help us we put them in our good books.Imagine what chaos would ensue if you were unable to keep track of those who’ve been non-cooperative toward you? They’d continue to take advantage of you causing you tremendous loss.Interestingly, we not only keep track of those who’re good or bad to us but also how much they’re good or bad to us. This is where reciprocal altruism kicks in. If a person does x amount of favour upon us, we feel obliged to return the favour in x amount. If a person does a huge favour upon us, we feel obliged to repay in a big way (the common expression, “How can I repay you?”). If person does a not-so-big favour for us, we return them a not-so-big favour.Add to all this our capacity to understand each other’s needs, convey our own and feel guilty or bad if we’re disappointed or if we disappoint others. All these things are in-built in us to promote cooperation.It all boils down to cost v/s benefitsJust because we’re evolved to cooperate does not mean non-cooperation does not happen. Given the right circumstances, when the benefit of not cooperating is greater than the benefit of cooperating, non-cooperation can and does happen.The evolution of cooperation in humans only suggests that there is a general tendency in the human psyche to cooperate with others for mutual benefit. Generally, we feel good when cooperation that is beneficial to us happens and feel bad when non-cooperation that is harmful for us happens.