Bio3520
Chapter 6
Sexual Selection
Darwin outlined a model of
selection in many animals as a consequence of the
different
produced by the two sexes, resulting in
and
selection.
Intrasexual
selection
often occurs when males
for females.
Male-male
involves
behaviors such as
fighting,
interference,
and
cuckoldry.
Intersexual selection (or
choice
) often occurs when females are choosy about their male
mates.
models of mate choice can be broken down into three
classes.
benefits
such
as
gifts
and
removal
provide tangible evidence of male fitness.
Good
, indicated by
phenotypes
such as
body
coloration,
odor,
and
symmetry,
provide
benefits of favorable traits to the offspring.
selection
occurs when a male trait is linked to the gene for mating preference in females.
Mate choice may also be
via mechanisms such as
Pavlovian
conditioning
and
sexual
.
Cultural transmission may lead to
mate
-
choice
behaviors,
especially among females.
Mate choice may also occur by
bias
when females possess a preexisting neurobiological
bias
for a novel trait.