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Updated: May 25, 2026
09:34
Assessing Differences in Sperm Competitive Ability in Drosophila
Published on: August 22, 2013
Differential selection between the sexes and selection for sex
1CNRS, UMR 7144, Adaptation et Diversité en Milieu Marin, 29682 Roscoff, France. roze@sb-roscoff.fr
Evolution; International Journal of Organic Evolution
|January 27, 2012
Summary
Sexual reproduction
Area of Science:
- Evolutionary Biology
- Genetics
Background:
- Anisogamy, the difference in gamete size between sexes, incurs a twofold cost of sex.
- Differing selective pressures between males and females can impact the evolution of sexual reproduction.
- Intralocus sexual conflict may favor asexual reproduction, while male sexual selection might purge mutation load.
Purpose of the Study:
- To analyze the strength of selection on genes modifying sexual reproduction frequency when selection differs between sexes.
- To investigate the conditions under which costly sex is maintained or asexuality evolves.
Main Methods:
- A two-locus model was analyzed using quasi-linkage-equilibrium (QLE) analysis.
- Local stability analysis was employed.
- Predictions were verified through multilocus simulations.
Main Results:
- Costly sex can persist if selection is stronger in males than females but acts in the same direction.
- Complete asexuality evolves under all other forms of sex-specific selection.
- The study quantifies selection on modifier genes affecting sexual reproduction frequency.
Conclusions:
- Male-biased selection can maintain costly sex, but only under specific directional selection scenarios.
- Experimental fitness measurements can help elucidate sex-specific selection pressures on sexual reproduction.
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