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Parasitism, host immune function, and sexual selection
1Laboratoire d'Ecologie, CNRS URA 258, Université Pierre et Marie Curie, Paris, France. AMOLLER@HALL.SNV.JUSSIEU.FR
The Quarterly Review of Biology
|March 19, 1999
Summary
Parasite load negatively impacts male sexual traits, influencing mate choice. Immune function measures reveal stronger effects than parasite counts, highlighting parasite resistance in sexual selection.
Area of Science:
- Evolutionary Biology
- Behavioral Ecology
- Parasitology
Background:
- Sexual selection is influenced by parasites, with females potentially avoiding infected males or seeking parasite resistance genes.
- Existing studies present mixed evidence regarding parasite-mediated sexual selection hypotheses.
Purpose of the Study:
- To meta-analyze the relationship between parasite load and male secondary sexual character expression.
- To investigate factors influencing the strength of parasite-mediated sexual selection, including parasite type and host characteristics.
Main Methods:
- A meta-analysis synthesized data from existing studies on host-parasite systems.
- Studies were categorized by methodology (experimental vs. observational), parasite type (ecto- vs. endoparasites), and measurement (parasite load vs. immune function).
Main Results:
- A significant negative correlation was found between parasite load and male secondary sexual character expression.
- Experimental studies and ectoparasite data showed stronger negative relationships.
- Measures of host immune function revealed stronger effects than direct parasite load measurements.
Conclusions:
- Parasite resistance is a key factor in parasite-mediated sexual selection.
- Future research should prioritize immune function assessments for a clearer understanding of these dynamics.
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