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Sexually antagonistic polymorphism in simultaneous hermaphrodites.

Crispin Y Jordan1, Tim Connallon

  • 1Ashworth Laboratories, Institute of Evolutionary Biology, The University of Edinburgh, Kings Buildings, West Mains Road, Edinburgh, EH9 3JT, United Kingdom. crispin.jordan@ed.ac.uk.

Evolution; International Journal of Organic Evolution
|October 15, 2014
PubMed
Summary
This summary is machine-generated.

Sexually antagonistic selection in hermaphrodites is influenced by self-fertilization, which reduces genetic polymorphism and alters allele invasion dynamics. This contrasts with predictions for separate-sex (dioecious) species.

Keywords:
Adaptationbalancing selectionfitness trade-offgenetic hitchhikingintralocus sexual conflictsexual dimorphism

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Area of Science:

  • Evolutionary genetics
  • Population genetics
  • Reproductive biology

Background:

  • Sexually antagonistic (SA) selection arises from genetic trade-offs between male and female reproductive functions.
  • Existing SA selection theory is primarily developed for species with separate sexes (dioecious), not hermaphrodites.

Purpose of the Study:

  • To generalize the theory of SA selection to simultaneous hermaphrodites.
  • To investigate the impact of self-fertilization, dominance, selection intensity, and population size on polymorphism maintenance.

Main Methods:

  • Development of population genetic models for SA selection in hermaphrodites.
  • Analysis of model predictions under varying biological parameters.

Main Results:

  • Hermaphrodite models under outcrossing align with dioecious species predictions.
  • Self-fertilization significantly reduces stable polymorphism, diminishes dominance effects, and creates asymmetry in selection favoring female-beneficial alleles.
  • Selfing lessens genetic hitchhiking effects associated with SA alleles.

Conclusions:

  • Self-fertilization fundamentally alters SA selection dynamics in hermaphrodites compared to dioecious species.
  • These findings have implications for understanding the evolution of selfing syndromes and reproductive strategies.