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Updated: Jun 23, 2026
07:54
Manipulation of Ploidy in Caenorhabditis elegans
Published on: March 15, 2018
Differences between selection on sex versus recombination in red queen models with diploid hosts
1Department of Ecology & Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada. a.agrawal@utoronto.ca
Summary
Parasites may not favor genetic mixing (sex and recombination) in hosts as previously thought. Diploid models show parasites often select against both, with differing conditions favoring sex versus recombination.
Area of Science:
- Evolutionary Biology
- Genetics
- Parasitology
Background:
- The Red Queen hypothesis posits that parasites drive the evolution of sexual reproduction and genetic recombination in hosts.
- Previous models, often using haploid hosts, found sex and recombination to be equivalent.
- However, diploidy introduces complexities where sex and recombination are not equivalent due to segregation effects.
Purpose of the Study:
- To compare parasite-driven selection on modifiers of sexual reproduction versus recombination rate in diploid hosts.
- To investigate the distinct evolutionary pressures parasites exert on sex and recombination.
Main Methods:
- Theoretical modeling of parasite-host interactions in diploid organisms.
- Analysis of selection pressures on genes controlling sexual reproduction and recombination rates.
Main Results:
- Parasites generally select against both sex and recombination in diploid hosts.
- Recombination is favored more often than sex under parasitic pressure.
- Conditions favoring sex and recombination often diverge, with segregation effects significantly influencing selection on sex.
Conclusions:
- Parasite-driven selection on sex in diploids is influenced by segregation, not solely recombination.
- Short-term advantages often favor recombination, while sex may be favored by long-term benefits.
- Red Queen models focusing only on recombination may not accurately predict selection on sex in diploid hosts.
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