Intralocus sexual conflict and offspring sex ratio

Ecol Lett. 2012 Mar;15(3):193-7. doi: 10.1111/j.1461-0248.2011.01725.x. Epub 2012 Jan 8.


Males and females frequently have different fitness optima for shared traits, and as a result, genotypes that are high fitness as males are low fitness as females, and vice versa. When this occurs, biasing of offspring sex-ratio to reduce the production of the lower-fitness sex would be advantageous, so that for example, broods produced by high-fitness females should contain fewer sons. We tested for offspring sex-ratio biasing consistent with these predictions in broad-horned flour beetles. We found that in both wild-type beetles and populations subject to artificial selection for high- and low-fitness males, offspring sex ratios were biased in the predicted direction: low-fitness females produced an excess of sons, whereas high-fitness females produced an excess of daughters. Thus, these beetles are able to adaptively bias sex ratio and recoup indirect fitness benefits of mate choice.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Size
  • Coleoptera / physiology*
  • Female
  • Male
  • Sex Ratio*
  • Sexual Behavior, Animal*