Data from: Stalk-eyed flies carrying a driving X chromosome compensate by increasing fight intensity

Exaggerated ornaments provide opportunities for understanding how
selection can operate at different levels to shape the evolution of a
trait. While these features aid their bearer in attracting mates or
fending off competitors, they can also be costly and influenced by the
environment and genetic variation. Eyestalks of the stalk-eyed fly,
Teleopsis dalmanni, are of interest because eyestalk length is the target
of both intra-and intersexual selection and is also reduced by loci on a
highly-diverged sex ratio X chromosome (XSR), a meiotic driver accounting
for up to 30% of wild X chromosomes. Male stalk-eyed flies fight to
control access to females and over food using a combination of low
intensity displays and high intensity physical fights. We staged, filmed
and scored contests among eyespan-matched male pairs to evaluate whether X
chromosome type impacts the behavior and outcome of aggressive
interactions. While our results broadly match expectations from previous
studies, we find that XSR males used more high intensity behaviors than
males carrying a non-driving, standard X chromosome (XST), in particular
when their eyestalks were of similar size or smaller than their opponents.
Additionally, we find that when XSR males use high intensity behaviors
they win more bouts than when they use low intensity behaviors. Taken
together these results suggest that XSR impacts male aggressive behavior
to compensate for the shorter eyestalks of XSR males, and may help to
explain how this selfish chromosome is maintained.