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Updated: Aug 5, 2026
09:34
Assessing Differences in Sperm Competitive Ability in Drosophila
Published on: August 22, 2013
Does competitive divergence occur if assortative mating is costly?
1Department of Mathematics, University of Vienna, Wien, Austria.
Journal of Evolutionary Biology
|April 8, 2006
Summary
Assortative mating costs can prevent sympatric speciation. Moderate choosiness costs allow divergence, but high costs and strong assortment reduce genetic variation, hindering speciation.
Area of Science:
- Evolutionary Biology
- Population Genetics
Background:
- Sympatric speciation models often ignore assortative mating costs.
- Choosiness costs can impede speciation, contrary to some models.
Purpose of the Study:
- Investigate how assortment strength and choosiness costs affect speciation.
- Analyze a genetic model of a 'magic' trait influencing competition and mating.
Main Methods:
- Analytical and numerical investigation of a haploid population model.
- Examined parameters: selection, competition, assortment, and choosiness costs.
- Studied trait determination by a single locus with multiple alleles.
Main Results:
- No polymorphism or strong divergence can occur depending on parameters.
- Reproductive isolation is likely with intermediate/strong competition and very strong assortment.
- Divergence is weakly affected by costs unless they are high.
Conclusions:
- High choosiness costs, combined with strong assortment, deplete genetic variation and prevent divergence.
- Speciation likelihood depends on the interplay between competition, assortment strength, and choosiness costs.
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