Data from: Sexual selection, environmental robustness and evolutionary demography of maladapted populations: a test using experimental evolution in seed beetles

Whether sexual selection impedes or aids adaptation has become an
outstanding question in times of rapid environmental change and parallels
the debate about how the evolution of individual traits impacts on
population dynamics. The net effect of sexual selection on population
viability results from a balance between genetic benefits of “good genes”
effects and costs of sexual conflict. Depending on how these facets of
sexual selection are affected under environmental change, extinction of
maladapted populations could either be avoided or accelerated. Here, we
evolved seed beetles under three alternative mating regimes to disentangle
the contributions of sexual selection, fecundity selection and male-female
coevolution to individual reproductive success and population fitness. We
compared these contributions between the ancestral environment and two
stressful environments (elevated temperature and a host plant shift). We
found evidence that sexual selection on males had positive genetic effects
on female fitness components across environments, supporting good genes
sexual selection. Interestingly, however, when males evolved under sexual
selection with fecundity selection removed, they became more robust to
both temperature and host plant stress compared to their conspecific
females and males from the other evolution regimes that applied fecundity
selection. We quantified the population-level consequences of this
sex-specific adaptation and found evidence that the cost of socio-sexual
interactions in terms of reduced offspring production was higher in the
regime applying only sexual selection to males. Moreover, the cost tended
to be more pronounced at the elevated temperature to which males from the
regime were more robust compared to their conspecific females. These
results illustrate the tension between individual-level adaptation and
population-level viability in sexually reproducing species and suggest
that the relative efficacies of sexual selection and fecundity selection
can cause inherent sex-differences in environmental robustness that may
impact demography of maladapted populations.