Summer 2005

What follows is the full text of the Faculty Address delivered at the 2005 MA Convocation by Marina Cords, Associate Professor and Chair of the Department of Ecology, Evolution, and Environmental Biology


I am honored to be here to congratulate you, the graduating Master's students in Columbia's Graduate School of Arts and Sciences. The diversity of interests, programs and trajectories in this room is enormous, and might lead you to think that you have little in common with your peers beyond the color of your robes and this momentary intersection of your schedules. But in fact, I want to focus on something that all of you have in common. Today you officially join a new community, a community of scholars who have struggled with advanced learning in whichever field you call your own, and having mastered some part of it, will go on to use that knowledge wisely. Like any community, this is one where individual members take on various roles, but where the success of all community members depends on their cooperation. The heart of communities is in fact cooperation --- and cooperation to make and apply knowledge is, I believe, a uniquely and wonderfully human venture.

However, it is not only those who study humans who have pondered the workings of communities. I would like to lead you through some reflections on the notion of community from the perspective of a behavioral biologist, by situating communal humans -- the species Homo sapiens -- in a broader comparative perspective.

It is an exciting time to make that comparison: there has been a real shift, stemming both from logical reconsiderations and new empirical results, to recognize the cooperative nature of humans and their relatives. This recognition stands in contrast to a long history in which behavioral biologists emphasized the 'darker side' of human nature. From Thomas Henry Huxley's emphasis on a literal and nasty struggle for existence at the turn of the last century, to the 1967 book On Aggression, by Nobel prize winner Konrad Lorenz, many portrayed human aggressiveness as inborn and inevitable, a drive that was hard or impossible to control, that found expression in anything from sports to gang violence. There were those who disagreed -- the Russian anarchist and geographer Peter Kropotkin in the early 1900's and the (Columbia trained) anthropologist Ashley Montagu, among them -- but, perhaps testimony to the sometimes thick walls between academic disciplines and the significance of transnational boundaries -- behavioral biologists continued their focus on the destructive and seemingly unavoidably aggressive nature of our species. But things are changing.

An evolutionary biologist sees humans as one of the approximately 1.5 million terminal twiglets on the grand tree of life, where each of those twiglets is a known species alive today. But we can situate them a little more precisely, knowing that they are animals, vertebrates, mammals, and more particularly primates. As such we humans are related through a joint history lasting about 60 million years to the living kinds of prosimians, monkeys and apes, of which there are about 300 plus.

In The Origin of Species, Charles Darwin founded evolutionary biology on two ideas: (1) that all species are related to one another through a history of common descent and (2) that the exquisite match between a species and its environment is explained by natural selection, a process in which individuals with beneficial mutations leave more offspring. An important and powerful research tool for the evolutionary biologist is thus the comparative method, in which one or more features are compared across species.

Comparative studies allow us to discern which characteristics are common to all members of a given group of species, and which vary among them. The commonalities and the variation are interesting, because they allow us to infer when particular characters arose in evolutionary time, and why they arose.

Studying the evolution of behavioral characteristics is an undertaking that especially relies on the comparative method. After all, behavior doesn’t leave much in the way of fossil remains. So to investigate the evolutionary basis of human social behavior, we really have few alternatives but to examine a set of related species existing today, and see what they do and under which conditions. In a comparative perspective of our closest living relatives, the primates, we view features found in all primates as evolutionarily old: it is more parsimonious to assume that such a common feature evolved once, in some ancestor of the species that share it, than to assume that it evolved independently multiple times.

I want to focus on a set of behavioral adaptations that are common to all primates, including humans, and which thus appear to be evolutionarily old. These behaviors relate to managing conflict, and I will argue that they are part of a primate-wide nature, and the basis for living socially, in communities, in these animals, which include our own species.

Let's begin with the observation that all primates are social. Of course I don't mean that they go to lots of parties and chat a lot on the phone. A biologist thinks of social animals as those who have interactions with one another that go beyond the bare necessity of reproduction, and whose interactions are mediated by evolved systems of communication. Often they live in groups.

Especially important in the social lives of primates -- and this will seem familiar to you human primates -- is the fact that they engage in social relationships: A particular pair of individuals has a particular way of interacting, and the members of this pair accumulate a unique history of past interactions that influences the course of future interactions. A typical primate engages in several social relationships at any one time, and these relationships vary in terms of the amount and kind of behavioral exchange that occurs. Perhaps they differ subjectively to the animals too -- but this is not something that science can measure, at least not yet.

All this may sound very familiar, even obvious, to all of us human primates. But, not all social animals engage in social relationships: this is something quite special! E.g., ants are highly social creatures, living in large colonies with an intricate division of communal labor, and specialized signals for communication, but there is no evidence that 2 particular ants "know" each other as individuals.

You can't have social relationships unless you can recognize individuals, unless have a good memory, and unless you meet repeatedly -- most animals, even social animals, do not do all these things. But primates do.

The fact that all primates engage in social relationships, completely without exception, suggests that there must be real evolutionary advantages to doing so. Biologists have thought a lot about the question of how social relationships are beneficial in an evolutionary sense (in terms of fostering survival and reproduction) and they have come up with a number of possible answers.

Generally, we view relationships as providing ways of knowing, predicting or influencing the behavior of other individuals, particularly those in the same social network. Other individuals in your network are potentially useful to you in multiple ways: may be tolerant of your feeding nearby, may provide protection against predators, help in raising the young, or may take your side in aggressive confrontations with other individuals or other groups. Of course this is usually a two-way exchange, so that both partners benefit in some way from their relationship, though perhaps not in the same way.

So, from an evolutionary perspective, we view social life as a cooperative solution to various challenges the environment poses to almost every animal -- feeding oneself adequately and efficiently, protecting oneself effectively, finding a suitable mate, and raising offspring. Forming and nurturing social relationships with a diversity of partners allows individuals to achieve these ends.

But maintaining social relationships is also difficult. Your own experiences are surely very similar to those we study in other social animals – and lead us to know that conflict between social partners is rife! This is not surprising! No matter what ultimate interests two individuals may have in common, they do not always agree in terms of their immediate goals, and sometimes they are competitive with each other and maybe even downright aggressive. Living together makes conflicts more likely to happen!

Conflicts are potentially a problem for animals committed evolutionarily to a social existence. For the individual, they are at least frustrating, often stressful, and maybe even physically dangerous. For the individual within a social network, they threaten to undermine the set of relationships upon which that individual ultimately depends for its well-being and survival.

And yet we do find among some social animals, and especially among the primates, enduring social relationships that last for years and even for lifetimes. The social networks of these animals are incredibly stable: in most cases, for example, either males or females remain in the group in which they were born throughout an entire lifetime, and have lifelong relationships with others doing the same thing.

How do they manage to stay together, when conflict is unavoidable, and threatens to drive them apart?

We have learned from studying our closest relatives that they have well developed behavioral mechanisms to manage conflict. Some of these work through the control of aggressive expression and others through conflict resolution.

Many conflicts are simply avoided when members of a society use conventions to settle potential disputes. A convention is a set of mutually accepted expectations (rules) that specifies behavior in particular situations. Knowing your dominance status, not being challenged for ownership, and using habitual travel routes are all examples of conventions that are used in monkeys and apes. Driving on one side of the road or taking turns in conversation are examples of conventions that humans use.

Another strategy is to anticipate conflict, and reduce its intensity. Monkeys and apes will do this by embracing, kissing, and grooming each other especially often in situations when conflict is likely to erupt. It's a bit like a team honing its coordination through a pre-game pep-rally.

If conflict does erupt, we find primates inhibiting violence. Though they come armed with saber like teeth, these are used very rarely, and other forms of physical aggression are similarly rare. Redirecting aggression on to others, and interfering in the interactions of others, are used by many primates to bring aggressive conflict to an early end.

Recently, we've learned a lot about the other part of conflict management, which is conflict resolution. It might seem odd to characterize aggression itself as a form of negotiation, but after decades of viewing aggression as anti-social, we are beginning to understand it better as way of negotiating: communicating your position, and at least threatening punishment are powerful tools in any negotiation process.

Reconciliation is a form of conflict resolution, that occurs after a conflict has been expressed. Reconciliation has been found in every non-human primate species that has been examined. In a typical case, one comes upon two individuals engaged in some kind of disagreement. May be violent, with screaming or biting, or (more usually) a relatively mild one.

What's remarkable is that usually in the first few minutes after the two opponents have separated, and their conflict appears to be over, they are very likely to get back together again, but not to continue their aggression. Their reunions are friendly, including hugging and kissing in chimpanzees, hand holding in leaf monkeys, grooming, or even just sitting near one another. After this reunion, the former opponents are relaxed, and relaxed with each other, and can interact without fear or hostility, as they did before conflict erupted in first place.

This is a rich set of social capabilities designed to maintain cooperative, communal life in the primate order. In emphasizing this cooperative part of our social nature, I don’t mean to imply that we (and our close relatives) are without the natural potential for aggression and violence – our media make that potential clear on a daily basis. My point is that cooperation in communal efforts is just as much a part of where we came from and who we are – a part of our evolutionary heritage, our fundamental nature as primates on the tree of life.

We, as humans, uniquely take this primate nature one step further, by belonging to multiple communities. Today you add one to your lives-- a community of scholars -- and so, no doubt, you will continue to add communities to your lives in the future. I could wish you nothing more natural! Congratulations to Class of 2005!