Male courtship behaviors and female choice reduced during experimental starvation stress

Mating behaviors may exhibit trade-offs with survival because the energy allocated and time devoted to survival may reduce those available for mating behaviors that are important for reproduction. Long-term selection experiments for survival in stressful conditions are valuable for understanding how survival traits may trade-off with other traits, such as reproduction. We investigated how courtship behaviors and female choice may vary under stressful conditions in Drosophila melanogaster by mating females and males from starvation–selected lines with unselected-control lines. Males from starvation-selected lines had reduced courtship behaviors with fewer wing bouts per minute and shorter duration of wing bouts compared to control males, regardless of female pairing. These results are consistent with increased survival in starvation conditions showing trade-offs in males. Female mate selectivity also showed significant evolutionary changes with unselected-control females exhibiting differential courtship durations: shorter courtship durations when paired with males from unselected-control lines and longer courtship durations with males from starvation-selected lines. In contrast, starvation-selected females showed no significant differences in courtship duration between unselected-control and starvation-selected males despite the reduction in starvation–selected male courtship behaviors. We discuss how these results may indicate that starvation selection altered the interaction between females and males for mating ability and preferences in a complex manner consistent with life-history trade-off models.