Download Rape: A Reproductive Strategy?

Animal
Behavior
Background
This looks like rape but it isn’t (for one thing this is a dead bird, ugh). The more
important point is that a male songbird cannot forceably mate a female – she
has to cooperate for insemination to occur. This is true for many animals,
including many mammals. Extra-pair mating is common in songbirds (all of the
4000 species so far studied anyway), but rape is not.
An animal example: Male bank swallow follows a ‘mixed’ reproductive strategy
– he mates monogamously but while mate is incubating the eggs, he pursues
promiscious (extra-pair) matings with other females (Beecher & Beecher 1979).
Rape:
A Reproductive
Strategy?
However, rape (forceable
insemination) does occur in many
animals, including these beetles
(Alcock chapt 14). Another well
known example is the mallard
duck. And, of course, humans.
Many evolutionary psychologists
think you can best understand
rape by starting with the
hypothesis that the ultimate
explanation relates to its potential
reproductive consequences.
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because he hated women
Why did
felt the need to dominate someone
had been abused as a child
had drunk too much
had too much testosterone circulating in his body
was compensating for feelings of inadequacy
had been raised in a patriarchal culture
had watched too much violence on television
was addicted to violent pornography
was sexually aroused
hated his mother
hated his father
had a rare violence-inducing gene
that man rape?
¾ These are all proximate-cause explanations of behavior. One or more of
them could be true, but none of them address the ultimate cause of the
behavior or of the underlying psychological mechanisms.
¾ Thornhill & Palmer consider various possible ultimate-cause (evolutionary)
explanations of rape in humans.
¾ Note: proximate-cause and ultimate-cause explanations are not competing
explanations, but that they do have to be consistent with each other.
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Thornhill & Palmer: Rape as a reproductive strategy
Since women are choosy, men have been selected for
finding a way to be chosen.
¾ One way to do that is to possess traits that women prefer
(e.g., symmetry).
¾ A second way that men can gain access to women is by
defeating other men in fights or other kinds of
competitions – thereby gaining power, resources and
social status, other qualities that women find attractive.
¾ Rape can be understood as a third kind of sexual
strategy: one more way to gain access to females.
These hypotheses make predictions that can be tested. For example, in contrast to the
‘rape as violence’ hypothesis, the evolutionary hypotheses predict that rape should be
directed selectively towards fertile females (in contrast to non-rape violent crimes).
Rape can be understood as a 3rd kind of sexual ‘strategy’:
one more way to gain access to females.
1. Men might resort to rape when they are socially disenfranchised, and
thus unable to gain access to women through looks, wealth or status.
(Alternative mating strategy, “Making the best of a bad situation”)
Over evolutionary time, some men may have succeeded in passing on
their genes through rape, thus perpetuating the behavior.
2. Alternatively, men could have evolved to practice rape when the costs
seem low – when, for instance, a woman is alone and unprotected
(and thus retaliation seems unlikely), or when they have physical
control over a woman. (Mixed, conditional mating strategy)
Over evolutionary time, some men may have succeeded in passing on
their genes through rape, thus perpetuating the behavior.
3. It is also possible, however, that rape evolved not as a reproductive
strategy in itself but merely as a side effect of other adaptations, such
as the strong male sex drive and the male desire to mate with a variety
of women. [Note: in this case rape is not actually considered a
‘strategy’ or an adaptation, instead it is viewed as a deleterious side
effect of otherwise adaptive mechanisms relating to male sexuality.]
Evolutionary hypotheses 1 (alternative mating strategy) and 3 (by-product) predict that
incidence of rape should be higher when mating opportunities are fewer (degree of
polygyny greater). In modern society, divorce and remarriage of older men with
younger women leads to greater reproductive variance in men (effective polygyny).
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