Indiscriminate females and choosy males: within- and between-species variation in Drosophila.

The classic view of choosy, passive females and indiscriminate, competitive males gained theoretical foundations with parental investment theory. When females invest more in offspring than males, parental investment theory says that selection operates so that females discriminate among males for mates (i.e.

Mutual interest between the sexes and reproductive success in Drosophila pseudoobscura.

The pre-mating behavior of female Drosophila pseudoobscura has been considered passive and "coy" relative to more active, "ardent," and indiscriminate male behavior. To test whether this long-held view-the "received wisdom" about mating behavior in Drosophila-is really true we carried out observations on how often D. pseudoobscura females approached males prior to courtship and copulation.