Evolution Of Human Sex Roles More Complex Than Described
By Universal Theory
ScienceDaily (Apr. 27, 2009) — A new
study challenges long-standing expectations that men
are promiscuous and women tend to be more particular when it comes to choosing a mate.
The research suggests that human mating strategies are not likely to conform to a single
universal pattern and
provides important insights that may impact future investigations of
human mating
behaviors. In 1948, Angus J. Bateman's performed some
now famous studies in fruit flies that showed
that males exhibit greater variance in mating success (the number
of sexual partners) and in
reproductive success (the number of offspring) when
compared to females. In addition,
Bateman demonstrated that there was a stronger
relationship between reproductive success
and mating success in males than females.
Bateman concluded that, because a single egg is more
costly to produce than a single sperm,
the number of offspring produced by a female fruit fly was
mainly limited by her ability to
produce eggs, while a male's reproductive
success was limited by the number of females he
inseminated. These studies supported
the conventional assumption that male animals are
competitive and promiscuous
while female animals are non-competitive and choosy.
"The conventional view of promiscuous,
undiscriminating males and coy, choosy females has
also been applied to our own species," says lead study author
Dr. Gillian R. Brown from the
School of Psychology at the University of St.
Andrews. "We sought to make a comprehensive
review of sexual selection theory and examine data on mating behavior and reproductive
success in current human populations in order to further our understanding of human sex
roles."
Dr. Brown and colleagues examined the general
universal applicability of Bateman's principles.
To test one of Bateman's assumptions, they collated data on
the variance in male and female
reproductive success in 18 human populations. While
male reproductive success varied more
than female reproductive success overall,
huge variability was found between populations; for
instance, in monogamous
societies, variances in male and female reproductive success were
very similar.
The researchers also examined factors that might
explain variations across human populations
that are not in keeping with the prediction of universal sex
roles. "Recent advances in
evolutionary theory suggest that factors such as
sex-biased mortality, sex-ratio, population
density and variation in mate quality,
are likely to impact mating behavior in humans,"
concludes Dr. Brown. "The insights
gained
from this new perspective will have important
implications for how we
conceive of male and female sexual behavior."
Courtesy of
http://www.sciencedaily.com
|
