Modern Mind

between two doves scores 50 but pays a penalty of – 10 for a long staring ritual, meaning he scores 40 in all. The loser is penalised —10 for also wasting time and staring. On average therefore any one dove, in competition with other doves, can expect to win half and lose half of his contests, so the average payoff is half the difference between +40 and – 10, which is +15. 42 Now assume a mutant, a hawk. He never backs down so wins every fight, at 50 a time. He enjoys a big advantage over doves whose average payoff is only +15. In such a world, there is a clear advantage to being a hawk. But now hawk genes spread through the population, and soon all fights will be hawk fights, where the winner scores +50 but the loser is so seriously injured that he scores —100. If a hawk wins half and loses half of his fights, the average payoff of all hawk fights is halfway between +50 and —100, which is —25. If, amid such society, a dove mutant arises, he loses all his fights but never gets injured, so his average payoff is o. This may not sound much, but it beats —25. Dove genes should now start to spread. Looking at the arithmetic in this way, communities of birds would eventually arrive at an evolutionary stable strategy (ESS) in which 5/12 are doves and 7/12 are hawks. When this point is reached, the payoff for hawks and doves is the same, and selection does not favour either of them. The point about this admittedly simple example is to show that a group of birds can take on a certain character while selection is taking place on an individual level.
    Now Dawkins moves on to a slightly more complex example. This time he asks us to assume that he is an animal who has found a clump of eight mushrooms – food. To these he attaches a value of +6 units each (again, these units are entirely arbitrary). He writes, ‘The mushrooms are so big I could eat only three of them. Should I inform anybody else about my find, by giving the “food call”? Who is within earshot? Brother
B
(his relatedness to me is ½ [i.e., he shares half my genes]), cousin C (relatedness to me = ⅛), and
D
(no particular relation: his relatedness to me is some small number which can be treated as zero for practical purposes). The net benefit score to me if I keep quiet about my find will be +6 for each of the three mushrooms I eat, that is +18 in all. My net benefit score if I give the food call needs a bit of figuring. The eight mushrooms will be shared equally between the four of us. The payoff to me from the two that I shall eat will be the full +6 units each, that is +12 in all. But I shall also get some payoff when my brother and cousin eat their twomushrooms each, because of our shared genes. The actual score comes to (1 × 12) + (½ × 12) + (⅛ × 12) + (0 × 12) = 19½. The corresponding net benefit for the selfish behavior was +18: it is a close-run thing, but the verdict is clear. I should give the food call; altruism on my part would in this case pay my selfish genes.’ 43 Dawkins’s overriding point is that we must think of the central unit of evolution and natural selection as the gene: the gene, the replicating unit, is ‘concerned’ to see itself survive and thrive, and once we understand this, everything else falls into place: kinship patterns and behaviour in insects, birds, mammals, and humans are explained; altruism becomes sensible, as do the relations of non-kin groups (such as races) to one another.
    Dawkins’s argument, eloquently made, and Wilson’s, together sparked a resurgence in Darwinian thinking that characterised the last quarter of the century. One remaining aspect of Dawkins’s and Wilson’s arguments is the link to Tom Wolfe, Christopher Lasch, John Rawls, and economics. They are yet another example of the way knowledge began to come together toward the end of the century. Wolfe’s book
The Me Decades,
Lasch’s
Culture of Narcissim,
and
The Selfish Gene
all reflect an emphasis on individuation and selfishness. They were quite different books, with ostensibly different aims, but the selfish theme common to them all was remarkable. The link to John Rawls’s
Theory of Justice
is that his ‘original position’ and ‘veil of ignorance’ describe what is essentially the very opposite of the position the selfish gene is in: no one knows their inheritance, and only by not knowing, Rawls is saying, can we ever hope to arrive at a true system of fairness, a way of living life together with selfishness