Sex-Related Comparisons: Theory 145interactionistic (Confer et al., 2010). The
environment influences the mechanisms
that evolve. All evolved mechanisms require
some kind of environmental input. Behav-
ior that evolved for survival reasons can be
influenced by the culture, such as the ex-
ample of the influence of birth control pills
on sexual behavior. The goal of evolution-
ary theory is to understand the evolutionary
forces that shape behavior. One limitation of
evolutionary theory is the inability to explain
behaviors that do not maximize reproductive
success, such as homosexuality, adoption of
children, and suicide. A second limitation is
that evolutionary theory does not account
for individual differences or cultural differ-
ences in behavior.TAKE HOME POINTS
■ Because males and females face different challenges
in ensuring the survival of their genes, sex differ-
ences in sexual behavior have evolved. Males prefer
to have sex with as many fertile women as possible,
and females prefer to have sex with a male who can
provide economic resources to ensure the survival of
their children.
■ Because men are in competition with one another over
women, men behave in aggressive ways especially
when trying to establish dominance or when competing
with rivals.
■ Women’s greater investment in children could
be one explanation for the evolution of the hunter-
gatherer society. The structure of that society has
been linked to some sex differences in social behavior
and cognition.
■ Evolutionary theory has a deterministic tone but is
really interactionistic, as evidenced by the fact
that cultural factors can override earlier evolved
tendencies.The Hunter-Gatherer Society
Evolutionary theory suggests that the hunter-
gatherer society developed from women’s
stronger investment in children compared to
men. With women caring for children, men
were left to hunt. The hunter-gatherer soci-
ety has been linked to sex differences in both
social behavior and cognition (Ecuyer-Dab &
Robert, 2004). In terms of social behavior,
men behave aggressively because aggression
was required to hunt and feed the family;
women evidence nurturance because nurtur-
ance was required to take care of children.
Women became emotionally expressive and
sensitive to the emotions in others because
they were the primary caretakers of chil-
dren. Men learned to conceal their emotions
because a successful hunter needed to be
quiet and maintain a stoic demeanor to avoid
being detected by prey. In terms of cognition,
men’s greater spatial skills and geographic
knowledge could have stemmed from their
venturing farther from the home than
women when hunting. Women’s greater
ability to locate objects could be linked to
their having to keep track of objects close
to home; foraging for food, in particular,
required women to remember the location
of objects.A Final Note
Some people find sociobiology and evo-
lutionary theory distasteful as an explana-
tion for sex-related differences in cognitive
and social behavior, in part because these
theories make sex-related differences seem
unchangeable and view traditional roles
as “natural.” The concern is that wom-
en’s and men’s different roles must have
been—and still are—desirable if they led to
survival. However, others suggest that evo-
lutionary theory is not deterministic butM05_HELG0185_04_SE_C05.indd 145 6/21/11 8:03 AM