Evolutionary Ethics 225date, built under the influence of genes that were selected in some earlier era when
conditions were different” [ibid., 35]. Questions about the adaptive significance
of some currently-observed form of behaviour — based on the assumption that it
must be favourable for the animal practicing it under current conditions — are as
a result very often ill-posed. With this framework in place, the reader is invited
to consider some foci of current debates concerning the relevance of evolutionary
considerations to topics of particular interest to contemporary moral philosophers,
including altruism, reproductive strategies, and the control of aggression.
3 THE EVOLUTION OF ALTRUISMThe evolution of altruism presents a raft of theoretical and conceptual prob-
lems. Altruism and its relatives — co-operativeness, a disposition to fairness and
promise-keeping even under circumstances unfavourable to the agent, beneficence,
and benevolence — have traditionally occupied pride of place in moral theory.
To what extent can these dispositions be explained as adaptations and to what
extent are they maintained by other, non-genetic replicatory systems? The ob-
servation that many forms of human behaviour can reproduce themselves through
the mediation of beliefs and attitudes and spread through a population and its
descendants without contributing to fitness led Dawkins to introduce a separate,
ideational system of replicators, which he called “memes” [Dawkins, 1976, 206ff.].
The position ascribed to Huxley is that human moral behaviour, especially the
value it attaches to peace, justice, and fairness is entirely memetic; increasingly
however, this position has been questioned.
It is easy to show that the theory of rational choice does not predict rewards for
fair, altruistic, co-operative agents, but the introduction of “replicator dynamics”
in which the payoff is not in dollars or well-being but in copies of oneself, changes
the picture in some surprising ways. Sober and Wilson characterize altruism (in
the sense relevant to evolutionary theory) not simply as helping behaviour, or even
as helping behaviour involving certain risks to the altruist, but as “behaviour...
[that] involves a fitness cost to the donor and confers a fitness benefit on the recip-
ient” and they propose an evolutionary explanation for it. On initial inspection, it
seems logically impossible that such behaviour could be manifested in an organism
let alone explained: how can a trait that renders each of its possessors likely to
have fewer than the average number of offspring escape being driven to extinction?
To solve their paradox, Sober and Wilson revert to the Darwinian hypothesis that
altruism can be accounted for by competition amongst groups [Sober and Wil-
son, 1998]. Groups without any altruists die off; those with some proportion of
altruists persist. The counter-intuitive aspects of the Sober–Wilson hypothesis,
which does not satisfactorily explain how a low-reproducing altruist can invade
a population of egoists in the first place, nor why an altruistic population is not
subject to invasion by high-reproducing egoists, are somewhat mitigated by the
observation that individual organisms are groups too — federations of genes and
their products. Certain combinations are fortunate ones, even if some of their