Data from: Condition-dependent interaction between mating success and competitive fertilization success in Drosophila melanogaster

Dietary restriction during development can affect adult body size and
condition. In many species, larger (high-condition) males gain higher
mating success through male-male competition and female choice, and female
condition can affect the extent of both female mate choice and male
investment in courtship or ejaculates. However, few studies have examined
the joint effects and interplay of male and female condition during both
the pre- and the post-copulatory phases of sexual selection. We therefore
manipulated the larval diet of male and female Drosophila melanogaster to
study how body size variation in both sexes biases competitive outcomes at
different reproductive stages, from mating to paternity. We did not find a
difference in mate preference or mating latency between females of
different conditions, nor any interaction between male and female
conditions. However, large males were more successful in gaining matings,
but only when in direct competition, whereas mating latencies were shorter
for low-condition males in non-competitive settings. Small males also
transferred more sperm to non-virgin females, displaced a larger
proportion of resident sperm and achieved higher paternity shares per
mating than large males. In agreement with existing theory, we suggest
that small males might partially compensate for their low mating success
by strategically investing in larger sperm numbers and potentially other,
unmeasured ejaculate traits, when they do have a mating opportunity.