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Same-sex sexual behaviour and selection for indiscriminate mating.
Brian A Lerch1, Maria R Servedio2
1Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. blerch@live.unc.edu.
Nature Ecology & Evolution
|November 10, 2020
Summary
Same-sex sexual behaviour (SSB) may be an optimal strategy, not an evolutionary puzzle. Our model shows indiscriminate mating is often the best approach, potentially explaining SSB
Area of Science:
- Evolutionary biology
- Behavioral ecology
- Genetics
Background:
- Same-sex sexual behaviour (SSB) presents an evolutionary paradox due to the reproductive costs incurred by participants.
- Limited research has explored SSB as a potentially optimal strategy, particularly if indiscriminate sexual behavior was ancestral.
Purpose of the Study:
- To develop a theoretical framework for the evolution of indiscriminate sexual behaviour.
- To test the hypothesis that SSB can be maintained by selection for indiscriminate mating.
Main Methods:
- Construction of a simple mathematical model of sexual reproduction.
- Analysis of conditions favoring indiscriminate sexual behavior as an optimal strategy.
Main Results:
- Indiscriminate mating is demonstrated to be the optimal strategy under a broad range of conditions.
- The model suggests conditions favoring indiscriminate mating likely existed at the origin of sexual behavior.
Conclusions:
- Selection for indiscriminate sexual behaviour provides a strong explanation for the maintenance of SSB.
- Findings offer insights into the evolutionary origins of both SSB and discriminate sexual behaviour in nature.
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