The Selfish Nature of Human Cooperation

An optimistic anthropological perspective on human nature has emerged in the last two decades: the view that cooperation is the most essential human activity and that conflict, violence, and moral evil only recently developed in human history as a result of the emergence of agriculture over the past several thousand years. This position is not entirely unfounded, but its advocates often move beyond offering an interpretation of human behavior, ultimately ignoring crucial facts about the essential nature of human intentions for the sake of building their optimistic narrative.

For instance, at a recent lecture at my university’s philosophy department, a speaker argued as follows: Not only did humans share food and other essential items in our earliest hunter-gatherer societies; at our core, we enjoy sharing, and competition and cooperation can be disentangled from one another completely. The speaker emphasized the non-violent, sharing, and cooperative nature of modern hunter-gatherers and criticized chimpanzee-centric models of human evolution on the basis that modern humans are just as genetically similar to bonobos as they are to chimps. He stated that agriculture is the true inner demon of modern society and that we are essentially good.

Ideas like these are not new at all. They hearken back to Rousseau’s fable of the noble savage. In Marx’s views of the cycle of history they emerged as the primitive communists. And they’re ever-present in the new-age neoliberal sentiment of the shared inherent goodness of all human beings. Unfortunately, they are wrong. And in using anthropological data, proponents of this viewpoint have erased the harsh reality of man as a selfish, biological creature geared with a Machiavellian intelligence and urge to win. They have obscured the reality of cooperation as a necessity and have erased human intent from the equation.

It is clearly and universally evident, for example, that hunter-gatherers share meat even outside of their familial groups. This pattern can be mapped everywhere from the Arctic to the Amazon; meat sharing is a cultural universal. But why do they share? The optimists seem to evoke imagery like that of children exchanging toys on a playground, or of the Whos down in Whoville, finding themselves destitute and without gifts on Christmas morning but joining hands with one another in a defiant act of communitas against the wicked, selfish cheater Grinch.

But I believe we (by we, I also mean hunter-gatherers) do not entirely enjoy sharing. The ethnographic literature makes evident that hunter-gatherers share only what cannot be hidden, and ethnographic reports by anthropologists have notoriously shown that hunter-gatherers hide meat acquired during hunting expeditions from each other in an attempt to not be obligatorily “shared out” of the fruits of their labor (Peterson 1993). Shame, coercion, and obligation appear to be the modes by which hunter-gatherers are moved to share. Sharing is a necessity — often up to 65% of a hunter-gatherer’s diet consists of protein acquired on hunting expeditions, and every hunter is unsuccessful on some hunts. In an attempt to reduce variance for returns of a dietary essential, hunter-gatherers share with one another. Are these people cooperating? Yes, but to understand the nature of such cooperation we must take into account the actions of hiding, shaming, and coercing.

Experiments in game theory help illuminate this reality by subjecting humans, both agricultural and hunter-gatherer, to several monetary-based sharing games. In one study, fourteen authors conducted a cross-cultural study of what is known as a third-party punishment game (Henrich et al. 2006). In this game, three players are given the job of dividing their funds whichever way they see fit. The first player is given a monetary endowment of 100 units to share however they would like with a second player, who may only receive whatever the first player gives them. A third player is given a smaller endowment of 50 units, and upon seeing how much the first player has given to the second, is given the option to spend a portion of their smaller endowment to punish the first player. The authors found, cross-culturally, that players chose to punish those who did not share, and as offers between players increased to more equal distributions, the frequency of punishments decreased. Additionally, societies whose subjects punished more also exhibited higher rates of unrelated reciprocal altruism in the ethnographic record. (In reciprocal altruism, exchanges of essential goods between individuals are not immediate and the initial giver incurs a cost with the expectation that this cost will be repaid in the future.) It is true that the act of punishment incurs a cost to the punisher in these experiments, which means the punishment can be seen as an altruistic act. But given that it is also the result of a cultural system which has been selected for in previous millennia, this obligation to punish unfairness is probably better viewed as analogous to the necessary variance-reduction strategies enacted by most hunter-gatherer groups which share meat.

In another study, Fehr and Gächter (2002) found a powerful correlation between punishment and sharing in games involving large public shares. Players could contribute individual earnings to a public pot for an overall increase in earnings for everyone. Two versions of the game were played: in one game, players had to rely on cooperation without punishment; in the other, players could choose to spend their own funds to punish members who did not contribute to the pot. The results are shown below, and clearly illustrate the role of punishment in cooperative systems. In both of these examples, punishment is the strongest correlation for equal sharing within groups. The egalitarian result seen in these studies is only obtained through the willingness of individuals to punish other individuals when they observe them acting unfairly. The observation that societies with the highest levels of sharing also enact the strongest punishments yields two conclusions: being stingy is not an option in these cultures, and the drive to share is partially driven by scorn.

Within primate troops, kinship groups compete with one another through infanticide and feeding cooperation; between troops of most primate species, aggression is a common occurrence. Primate group sizes are limited by the number of resource patches in their environments. These patches can only provide a limited amount of food to a single group of animals with a specific metabolic requirement. This constraint leads to competition and the enforcement of territorial boundaries between primate groups; cooperation in primates does not take place to increase the productivity of environments, rather it’s the case that the productivity of environments determine the scale of cooperation. In any event, the dynamics of antagonism are much different than the dynamics of cooperation. It takes much more time to become another primate’s friend than to immediately cut ties through a scuffle. A single glance (something primates often avoid and something primatologists rarely record) can reinforce the hierarchy of the pecking order far cheaper energetically than a scuffle can. The finding that on an individual basis primates will cooperate more than they will fight one another should not surprise anyone though because the cost of fighting with the individuals you encounter in your daily life is far costlier than ensuring a stable food supply by enforcing boundaries with several other individuals. Yet competition with other primates is still taking place at an evolutionary and ecological level.

A view of cooperation as ever-important is also present in biological anthropology’s study of the primates. Many primatologists, wishing to distance themselves from Richard Dawkins’s neo-Darwinian evolutionary perspective which emphasizes competition at the genetic level, have sought to emphasize cooperation in their own theoretical approaches. In an essential and foundational paper for students of primatology, Sussman et al. (2005) measured rates of aggressive behaviors versus cooperative ones in a number of species across the Primate Order. Although this approach illustrated well that primates, like humans, are in any given moment cooperating more than they are fighting, it must be taken into consideration with several other factors.

In rejecting a chimp-centric model of human evolution, several mistakes have also been made. Recent evidence has supported the hypothesis that bonobos may be more similar* to the last common ancestor (LCA) of chimps and bonobos than chimpanzees are, but this information is irrelevant when attempting to reconstruct the behavior of the LCA of bonobos and chimpanzees. Why do bonobos behave the way they do? Environment can contribute to the facts of human behavior and the social variability we see today, and this is probably the case with bonobos as well. The predominant hypothesis was proposed by primatologists Frances White and Richard Wrangham in 1988. Their theory was that the peaceful nature of bonobos is largely influenced by lack of competition for resources. Bonobos, living in a separate environment, rely on ubiquitous, less patchy sources of food for their dietary needs. Unlike chimpanzees, bonobos need not wander to find food sources, and so competition between individuals is unnecessary. Given this hypothesis, shouldn’t there be lower rates of aggression amongst agricultural groups than hunter-gatherers, due to increased food availability? The evolutionary split between bonobos and chimpanzees occurred roughly 1 million years ago, and some authors have suggested that bonobos have undergone rapid aggressive behaviors since then (Hare et al. 2012). Recent work has shown that a gene linked to fight-or-flight expression, ADRA2c, missing from the bonobos and present in both humans and chimpanzees may provide at least one causal link for what has come to be known as the self-domestication hypothesis (Lee et al. 2018).

So, what is happening with agriculture that we are not seeing in hunter-gatherers? The anthropologists Leslie White and Robert Carneiro would argue that we are seeing amplification due to increased scaling in population size. In the case of agriculture and population growth, the true wicked nature of humanity is simply revealed and placed on a stage for all to see. Nothing new has happened. Hunter-gatherers, whose lifeways are currently restricted by the resources available to them in their environment, possess a resource holding potential (RHP) which is effectively zero. Despite this fact, by their means of shame, hiding, and coercion, they reveal certain truths about human agency. The anthropologist Sherry Ortner proposed that systems of dominance we observe in society are systems of separate individuals’ competing willful projects. She later goes on to define “agency” as the ability to pursue said projects. Often, although one may possess the desire to actively pursue a project, the structure of one’s environment and the projects of others will keep one’s own projects from being pursued. Just as in agricultural societies, the desire is there in hunter-gatherers, yet unrealized due to the necessities their environment and culture places on their lifeway patterns.

Unfortunately, many scholars continue to place cooperation in the framework of morality without fully considering the dynamics of cooperation. Do we have to commit scientific fallacies to reject biological essentialism? It is probably the case that humans are setting ourselves up for failure amidst blind positivity. If we are given the facts, we can better navigate our situation in the future, avoid missteps, and not set ourselves up for surprise in the recurring cycle of human nature. Ultimately, I do not believe an emphasis on cooperation is entirely misguided, but we must remember what cooperation really is. Although it is true that humans cooperate at a remarkable scale not seen outside of the eusocial insects, if we want to associate cooperation with morality, several factors need to be examined. These include who or what are we cooperating for or against, and which mechanisms encourage or enforce this cooperation. In many cases, the cooperative nature of humans is not catholic, it is exclusive. On a broader scale and in every society, cooperation as a collective project is to the benefit of the in-group and to the exclusion of the out-group. All forms of genocide and subjugation and all state-level systems more generally involve cooperation, and many forms of cooperation are inherently self-motivated. We each gain by cooperating. These motivations were present in our ancient past. Like the doctrine of uniformitarianism in geology, we should assume that behaviors we see present in humans today were present in humans yesterday and avoid moral-ethnocentric arguments by subjecting only agriculture to our scrutiny. To do so would be to commit a massive historical, anthropological, and philosophical fallacy.

*Edit – A previous version of this article said that evidence supported the hypothesis that bonobos were more closely related to the last common ancestor of chimps. This was a mistake.

Bibliography

Fehr E. and Gächter S. 2002. “Altruistic punishment in humans.” Nature 415(6868):137.

Hare B., Wobber V., and Wrangham R. 2012. “The self-domestication hypothesis: evolution of bonobo psychology is due to selection against aggression.” Animal Behaviour 83(3):573-585.

Henrich J., McElreath R., Barr A., Ensminger J., Barrett C., Bolyanatz A., Cardenas J. C., Gurven M., Gwako E., and Henrich N. 2006. “Costly punishment across human societies.” Science 312(5781):1767-1770.

Lee K. S., Chatterjee P., Choi E.-Y., Sung M. K., Oh J., Won H., Park S.-M., Kim Y.-J., Soojin V. Y., and Choi J. K. 2018. “Selection on the regulation of sympathetic nervous activity in humans and chimpanzees.” PLoS Genetics 14(4):e1007311.

Peterson N. 1993. “Demand sharing: reciprocity and the pressure for generosity among foragers.” American Anthropologist 95(4):860-874.

Sussman R. W., Garber P. A., and Cheverud J. M. 2005. “Importance of cooperation and affiliation in the evolution of primate sociality.” American Journal of Physical Anthropology 128(1):84-97.

White F. J. and Wrangham R. W. 1988. “Feeding competition and patch size in the chimpanzee species Pan paniscus and Pan troglodytes.” Behaviour 105(1):148-164.