A Short History of Evolution: Deconstructing the Promethean Spark (Part 3)

This article is part of Carl Coon’s ongoing “A Short History of Evolution” series. Click here to read all entries in this series.


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Last week we discussed language, that revolutionary adaptation that most distinctively separates us from the rest of life on our planet. Today we discuss altruism, the quality of doing good for others even at some personal cost. Our remote ancestors learned to talk and learned to be altruistic toward other members of their group at about the same time, and it is doubtful that either could have succeeded without the other.  

Altruism Appears to Contradict Natural Selection

Living things want to stay alive, at least until they've had a chance to reproduce. This is an essential property of life. According to natural selection theory, when there is a resource that individuals share, each individual will try to get as much as it can. When there is nothing to inhibit such selfish behavior, the most competent individuals will do best, and succeeding generations will reflect that success. When the resource is limited, the winners take all, and the rest are eliminated. There are exceptional situations where altruism occurs in nature despite the appearance that it contradicts natural selection. It appears in social insects, including some ants and termites, where only one individual in the colony, the queen, can reproduce. This means that her numerous sterile progeny can best ensure the survival of the collectivity's genes if they support and defend the queen, even at sacrifice of their lives. (The authors of Star Trek may have had this principle in mind when they created the Borg.) Another track has been altruism based on kinship. An animal can sacrifice its own interests if by so doing it enhances the prospects of another that shares much of the same genetic information. Mother bear may risk her life to save her cubs if it enhances the odds that her genes will survive, whether in her or in cubs that have half her genes. People today still feel compelled to act more altruistically toward close kin than toward others. We can ascribe this to 'family values' or to nepotism or to something in between, but it is there, a fact arising out of our genetic inheritance. The kind of altruism we need to explain here is the human ability to empathize and cooperate with humans other than close kin. Unlike the ants, and momma bear, this kind of altruism doesn’t have any obvious way of reconciling itself with the natural selection principle. And yet, altruism that involves more than kinship has prevailed in groups of humans ever since history began and earlier. It is the essential glue that enables us to cooperate with other humans. When and how did we acquire it? We need to distinguish between altruistic practices that evolved naturally and those that evolved culturally. In our own times, the failure to make that distinction has resulted in a lot of needless argument.[1] If we get embroiled in that argument here, this "short" history will be a lot longer. It's especially important at this juncture, therefore, to define our terms and stick with those definitions. Biological evolution is the framework within which life on our planet evolves. Natural selection is the process that governs how living things evolve. Cultural evolution is an offshoot of biological evolution that has emerged with the human introduction of intentionality and language. It is primarily concerned with cultural artifacts. Like its parent, its general direction is toward concentration of power and creating complexity out of simplicity. Group selection (including multilevel group selection or multilevel selection) is a subset of cultural evolution that refers specifically to evolutionary processes between groups.  

The Tragedy of the Commons

When there is a resource that individuals share, but it is only renewable over time and gets consumed so fast it gets used up, the individuals all lose, and both winners and losers suffer. This is the so-called tragedy of the commons, where a resource (grazing land held in commons) became overgrazed because there was no way to inhibit individual shareholders from taking as much as they could get, even though restraint would benefit all. In other words, cooperation favored every individual, but absent some outside force to get them cooperating, it didn't happen. This theme of the tragedy of the commons has been a core problem for our species ever since we became one, and its many variations still surface today. We constantly strive to devise restraints on individual selfishness that are strong enough to keep us enjoying the benefits of cooperation. Concepts of morality and justice evolved out of a sense that sometimes individuals had to go against their selfish interests if the group was to survive and prosper.  

The Prisoner’s Dilemma

This is a way to look at the tragedy of the commons that was cooked up at RAND in 1950, and has been analyzed in great depth since then.[2] Part of its beauty lies in the fact you can either play it with people or set it up as a computer game that can play through any number of repetitions more or less instantly. You start with a mixed population of people. You divide them into pairs such that no one is already acquainted with the person across from him. Everyone gets a card on which he or she votes either to cooperate or not. Voting is secret; the other person in the pair doesn't know you, hasn't talked to you, and has no prior knowledge of how you may be voting. The rules are that if both parties opt to cooperate, they each get a small reward. If one party votes to cooperate and the other one votes the other way, the cooperator loses his bet and the non-cooperator gets a reward greater than what he would get if they both cooperated. If they both opt against cooperation, nobody loses but nobody wins anything either. If you have an arena filled with such pairs, or set up a computer program that games this situation, and repeat the contest over multiple rounds, you find that the cooperators lose out. The winning strategy for the individual is non-cooperation, even though everyone would end up better off if everyone cooperated. Altruism has failed and selfishness prevails, and it all works out about the way Richard Dawkins' selfish gene theory says it should. The tragedy of the commons revisited. This is normally the way natural selection works. Progress occurs when selfish individuals combine for mutual advantage, not when individuals act against their own advantage. Mama bears and termite colonies are the exceptions, not the rule. But the whole picture changes when you introduce the human factors of intentionality and language. If a player can identify the fellow he happens to be paired with and expects to have a further round with him at some point, he is more likely to vote for cooperation the first time around, in the hope that even if the partner doesn't cooperate the first time he may later. In later rounds, if he remembers how his adversary behaved before, he will likely defect when dealing with a defector while cooperating when the other fellow is a recognized cooperator too. A computer game that incorporates this factor of reciprocity will produce a variety of outcomes depending on how the odds are set. If every player in the game knows how every other one voted in all the other person's encounters and not just with his, that reciprocity factor becomes strengthened to something like an absolute. Add this factor of reputation and the good guys will win every time. Reciprocity and reputation thus form a solid basis for group cooperation in societies small enough so that everyone can at least recognize everyone else in the group. This is how societies were organized in the period when our sapient ancestors were hunting and gathering, and it carried on for a while after the introduction of agriculture. There is no mystery here. We all live with a limited number of people we know and can trust, including both kin and friends and acquaintances. Back when we all actually lived in villages, altruism prevailed effortlessly, and naturally. It did not require any genetic modification—it was an effect intrinsic to our newly evolved mental capabilities. It co-evolved with language and culture. The further evolution of altruism is an integral part of the complex of behavioral changes and technological innovations that our ancestors used to bootstrap themselves out of the village level into more complex societies. We'll cover all that in the next chapter.

[1] Segerstrale, Ulrica, Defenders of the Truth, 2000.  We refer here to the great debate over sociobiology that raged within the scientific community during the latter part of the 20th century and still continues to misinform some scholars to this day. I have relegated the controversy, including this admirable reference, to a footnote because that's where it belongs.
[2] Nowak, Ibid., Pages 5-6  

This article is part of Carl Coon’s ongoing “A Short History of Evolution” series. Click here to read all entries in this series.