Sexual selection can remove an experimentally induced mutation load

Evolution. 2014 Jan;68(1):295-300. doi: 10.1111/evo.12238. Epub 2013 Sep 6.


Sexual selection is argued to be important for the removal of deleterious mutations, promoting population fitness, accelerating adaptation, and compensating for the two-fold cost of sex. Here we induced mutations in the dung beetle Onthophagus taurus using ionizing radiation, and tested the efficacy of sexual selection in their removal. Mutations reduced male precopulatory (strength) and postcopulatory (testes mass) sexual traits. Two generations of sexual selection were sufficient to remove mutations that affected male strength, but not testes mass. Induced mutations did not affect female productivity, which was elevated by sexual selection. Our results provide empirical support for the hypothesis that condition-dependent traits offer a large target for mutational variation, and that sexual selection can purge the genome of deleterious mutations and promote population fitness.

Keywords: Fitness variation; mutations; sexual selection; sperm competition.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Coleoptera / anatomy & histology
  • Coleoptera / genetics*
  • Coleoptera / physiology
  • Female
  • Fertility
  • Genetic Load*
  • Male
  • Mating Preference, Animal*
  • Mutation*
  • Selection, Genetic*
  • Testis / anatomy & histology