"Human
evolution
Hidden charms
Oct 11th 2007
From The Economist print edition
Lap dancers earn more
when they are most fertile
“BECAUSE academics may be unfamiliar with the gentlemen's club sub-culture,
some background may be helpful to understand why this is an ideal setting for understanding real-world
attractiveness effects of human female oestrus.”
No doubt readers of The Economist are equally unfamiliar
with this sub-culture, but for Geoffrey Miller of the University of New Mexico, who penned the words above in a
paper just published in Evolution and Human Behaviour, such clubs are a field site as revealing of human biology as
the Serengeti is of the biology of lions and antelopes. Dr Miller is an evolutionary psychologist—and the author of
the theory that the large brains of humans evolved to attract the opposite sex in much the same way that a
peacock's tail does. His latest foray, into the flesh-pots of Albuquerque, is intended to investigate an orthodoxy
of human mating theory. This is that in people, oestrus—the outward signs of ovulation—has been lost, so that men
cannot tell when women are fertile.
This theory is based on the idea that in evolutionary terms it benefits
women to disguise when they are fertile so that their menfolk will stick around all the time. Otherwise, the theory
goes, a man might go hunting for alternative mating opportunities at moments when he knew that his partner was
infertile and thus that her infidelity could not result in children.
However, this should result in an
evolutionary arms race between the sexes, as men evolve ever-heightened sensitivity to signs of female fertility. Dr
Miller thought lap-dancing clubs a good place to study this arms race, because male detection of female fertility
cues would probably translate into an easily quantifiable signal, namely dollars earned. He therefore recruited some
of the girls into his experiment, with a view to comparing the earnings of those on the Pill (whose fertility was
thus suppressed) with those not on the Pill.
The results support the idea that if evolution has favoured
concealed ovulation in women, it has also favoured ovulation-detection in men. The average earnings per shift of
women who were ovulating was $335. During menstruation (when they were infertile) that dropped to $185—about what
women on the Pill made throughout the month. The lessons are clear. A woman is sexier when she is most fertile. And
if she wishes to earn a good living as a dancer, she should stay off the Pill."
