Evolutionary Ethics 227rational choice, is increasingly clear. Altruism co-exists with self-favouring and kin-
favouring tendencies, automatic and emotional mechanisms co-exist with rational
calculation, the latter depending heavily on social learning and formal instruction.
The premise that human beings are basically selfish never actually licensed the in-
ference that our economic systems ought to give free rein to selfishness, but it was
assuredly taken to do so in many textbooks of economics. Depriving proponents
of that view of their descriptive premise can accordingly stimulate or even force
a re-evaluation of existing norms. Similar remarks apply to the discovery that
strategies for pacification, conflict mediation and reconciliation are prominent in
our near primate relatives [Flack and DeWaal, 2000]. The inference that major
conflicts are best resolved by force of arms because that is the human way to do
things is not only unlicensed, but ill-founded. The recognition that we may be
endowed with an innate responsiveness to peace-making gestures, provided suit-
able signals are forthcoming from our opponent, can only encourage moralists who
hope for a less violent world.
4 REPRODUCTIVE STRATEGIES AND THE TWO NORMS THEORYThe theory of evolution posits different dispositions, competencies, and prefer-
ences for males and females. Some theorists offer to derive the necessity of female
subordination and exclusion from challenging, honourable, and lucrative pursuits
from these differences. Interestingly, in much of the literature on Evolutionary
Ethics, practices such as racial segregation and discrimination are regarded as the
products of arbitrary prejudice, based in ignorance and harmful to persons and
the community, while practices such as occupational segregation by sex are argued
to be scientifically well-grounded and overall good for society, on the grounds that
men and women are intrinsically more different from each other than members of
different ethnic populations. The notion that human beings are a species that has
evolved in such a way that its females lack the physical, cognitive and emotional
resources that would enable them to attain male levels of political, intellectual
and artistic expression, or that the species has evolved in such a way as to deny
women opportunities for such expression, and that this state of affairs is desirable
or inevitable, needs in any event critical examination.
Humans are physically dimorphic, though less so than are many ape species:
gorilla males are twice as large as gorilla females, for example, and human males
have lost the large canines possessed by male apes, suggesting that encephalisation
is associated with a less combative mode of life. Human females are about 90% as
tall as males on average, weigh about 80% as much, and have 30% less upper-body
strength. Women have more fat and less muscle, differently structured immune
systems, and accordingly different susceptibilities to disease. Hormones and neu-
rotransmitters are secreted in different proportions. It is commonly assumed that
not only reproductive efficiency but sexual selection has played some role in shap-
ing the anatomies and appearances of the two sexes [Darwin, 1990; Cronin, 1991].
Cross-cultural differences between men and women that are generally agreed on in-