No evidence for heritability of male mating latency or copulation duration across social environments in Drosophila melanogaster

PLoS One. 2013 Oct 14;8(10):e77347. doi: 10.1371/journal.pone.0077347. eCollection 2013.

Abstract

A key assumption underpinning major models of sexual selection is the expectation that male sexual attractiveness is heritable. Surprisingly, however, empirical tests of this assumption are relatively scarce. Here we use a paternal full-sib/half-sib breeding design to examine genetic and environmental variation in male mating latency (a proxy for sexual attractiveness) and copulation duration in a natural population of Drosophila melanogaster. As our experimental design also involved the manipulation of the social environment within each full-sibling family, we were able to further test for the presence of genotype-by-environment interactions (GEIs) in these traits, which have the potential to compromise mate choice for genetic benefits. Our experimental manipulation of the social environment revealed plastic expression of both traits; males exposed to a rival male during the sensitive period of adult sexual maturation exhibited shorter mating latencies and longer copulation durations than those who matured in isolation. However, we found no evidence for GEIs, and no significant additive genetic variation underlying these traits in either environment. These results undermine the notion that the evolution of female choice rests on covariance between female preference and male displays, an expectation that underpins indirect benefit models such as the good genes and sexy sons hypotheses. However, our results may also indicate depletion of genetic variance in these traits in the natural population studied, thus supporting the expectation that traits closely aligned with reproductive fitness can exhibit low levels of additive genetic variance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Animals
  • Copulation / physiology*
  • Drosophila melanogaster / genetics*
  • Drosophila melanogaster / physiology*
  • Female
  • Gene-Environment Interaction
  • Genetic Variation
  • Inheritance Patterns / genetics*
  • Male
  • Models, Biological
  • Phenotype
  • Social Environment*
  • Time Factors

Grants and funding

Funding for this work was provided by the Australian Research Council Discovery Projects and ARC fellowships) to JPE and FGG. During the preparation of the manuscript FGG was also supported by the the Spanish Ministry of Economy through the Ramon y Cajal program and grant (co-funded by the European Regional Development Fund) CGL2012-34685. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.