Monday, March 31, 2014
Next lab meeting: WIP presentation
Next lab meeting I will present my thesis for the coming defence on Thursday. It would be really nice to hear your comments so I can make some final changes. Also, here is a short fly paper about sexual antagonistic selection on gene expression in Drosophila melanogaster. I think both the topic and method should be of interest in our group.
Evolution under monogamy feminizes gene expression in Drosophila melanogaster
Many genes have evolved sexually dimorphic expression as a consequence of divergent selection on males and females. However, because the sexes share a genome, the extent to which evolution can shape gene expression independently in each sex is controversial. Here, we use experimental evolution to reveal suboptimal sex-specific expression for much of the genome. By enforcing a monogamous mating system in populations of Drosophila melanogaster for over 100 generations, we eliminated major components of selection on males: female choice and male–male competition. If gene expression is subject to sexually antagonistic selection, relaxed selection on males should cause evolution towards female optima. Monogamous males and females show this pattern of feminization in both the whole-body and head transcriptomes. Genes with male-biased expression patterns evolved decreased expression under monogamy, while genes with female-biased expression evolved increased expression, relative to polygamous populations. Our results demonstrate persistent and widespread evolutionary tension between male and female adaptation.