454
idiosyncrasies. The twins like spicy foods and sweet liquors, are absent-minded,
fall asleep in front of the television, think it is funny to sneeze in a crowd of
strangers, flush the toilet before using it, store rubberbands on their wrists, read
magazines from back to front, and dip buttered toast in their coffee (Trivers, 1985,
100)
Human beings inherit a propensity to acquire behavior and social structures, a
propensity that is shared by enough people to be called human nature. The
defining traits include division of labor between the sexes, bonding between kin,
incest avoidances, other forms of ethical behavior, suspicion of strangers,
tribalism, dominance orders within groups, male dominance over-all, and
territorial aggression over limiting resources. Although people have free will and
the choice to turn in many directions, the channels of their psychological
development are nevertheless (…) cut more deeply by the genes in certain
directions than in others. While cultures vary greatly, they inevitably converge
toward these traits. (Wilson, 1994, in: Laland & Brown, 2002, 88)
Time and again, my sociobiological colleagues have upbraid me as a turncoat,
because I will not agree with them that the ultimate criterion for the success of a
meme must be its contribution to Darwinian ‘fitness’. At bottom, they insist, a
‘good meme’ spreads because brains are receptive to it, and the receptiveness of
brains is ultimately shaped by (genetic) natural selection. The fact that animals
imitate other animals at all must ultimately be explicable in terms of their
Darwinian fitness. (Dawkins, 1999, 110)
Cosmides and Tooby (1987) characterize the difference between the standard
social science view and their perspective as representing a choice between two
models of the mind, one that lays emphasis on a small number of domain-general
processes versus another stressing a large number of domain-specific modules.
(Laland & Brown, 2002, 182).
They expected one object when added to another to result in two objects and not
one or three, and that one object removed from an initial display of two should
result in one object, not two or none at all. (Plotkin, 2004, 133)
human reasoning changes depending on the subject matter about which one is
reasoning (Laland & Brown, 2002, 168).
The costs, measured in terms of the energy needed to fly to a specific height and
the number of times that a whelk must be dropped before it is smashed open, can
be traded against the benefits, the calorific value of each whelk. Observation of
actual behavior, of the height from which the whelks are dropped and the average
frequency for which this must be done when they are dropped from different
heights, can be compared with the predictions of a simple model that computes
what the optimal behavior which yields the greatest benefits against the least cost
is. (Plotkin, 2004, 119)
The principal goal of human behavioural ecology is to account for the variation in
human behaviour by asking whether models of optimality and fitness-