Sexually transmitted disease and the evolution of mating systems
Författare
Summary, in English
Sexually transmitted diseases (STDs) have been shown to increase the Costs Of multiple mating and therefore favor relatively monogamous mating strategies. We examine another way in which STDs can influence mating systems in species in which female choice is important. Because more popular males are more likely to become infected, STDs can counteract any selective pressure that generates strong mating skews. We build two models to investigate female mate choice when the sexual behavior of females determines the prevalence of infection in the population. The first model has no explicit social structure. The second model considers the spatial distribution of matings under social monogamy, when females mated to unattractive males seek extrapair fertilizations from attractive males. In both cases, the STD has the potential to drastically reduce the mating skew. However, this reduction does not always happen. If the per contact transmission probability is low, the disease dies out and is of no consequence. In contrast, if the transmission probability is very high, males are likely to be infected regardless of their attractiveness, and mating with the most attractive males imposes again no extra cost for the female. We also show that optimal female responses to the risk of STDs can buffer the prevalence of infection to remain constant, or even decrease, with increasing per contact transmission probabilities. In all cases considered, the feedback between mate choice strategies and STD prevalence creates frequency-dependent fitness benefits for the two alternative female phenotypes considered (choosy vs. randomly mating females or faithful vs. unfaithful females). This maintains mixed evolutionarily stable strategies or polymorphisms in female behavior. In this way, a sexually transmitted disease can stabilize the populationwide proportion of females that mate with the most attractive males or that seek extrapair copulations.
Publiceringsår
2002
Språk
Engelska
Sidor
1091-1100
Publikation/Tidskrift/Serie
Evolution
Volym
56
Issue
6
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Wiley-Blackwell
Ämne
- Evolutionary Biology
Status
Published
Forskningsgrupp
- Theoretical Population Ecology and Evolution Group
ISBN/ISSN/Övrigt
- ISSN: 1558-5646