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Updated: Jun 20, 2026
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Stable Isotope In-Vivo Labeling for Mass-Spectrometry Identification of Paternal Metabolites Transferred from Sperm to Oocyte During Fertilization
Published on: June 17, 2025
Promiscuous females avoid inbreeding by controlling sperm storage
Amanda Bretman1, Devi Newcombe, Tom Tregenza
1Centre for Ecology and Conservation, University of Exeter, Cornwall Campus, Penryn, UK.
Molecular Ecology
|August 22, 2009
Summary
Polyandrous female field crickets avoid mating with relatives. Unrelated males fertilize more eggs by contributing more sperm to storage, ensuring higher paternity success and reducing inbreeding.
Area of Science:
- Evolutionary biology
- Behavioral ecology
- Genetics
Background:
- Polyandrous females in various species can bias paternity against relatives postcopulation.
- The mechanisms underlying this paternity bias remain largely unknown.
- Field crickets exhibit sibling mating but reduce inbred offspring when mating with unrelated males.
Purpose of the Study:
- To investigate the mechanism by which polyandrous female field crickets bias paternity against related males.
- To determine the relationship between sperm storage and paternity success in competitive mating scenarios.
Main Methods:
- Utilized a novel competitive microsatellite polymerase chain reaction (PCR) technique.
- Assessed the contribution of individual males to stored sperm.
- Quantified subsequent offspring paternity based on sperm contribution.
Main Results:
- Offspring paternity was almost entirely predicted by the amount of stored sperm from a specific male.
- Unrelated males contributed significantly more sperm to storage compared to related males.
- Higher sperm storage by unrelated males corresponded to greater paternity success.
Conclusions:
- Sperm competition and storage mechanisms are key factors in paternity bias.
- Female field crickets actively favor unrelated males during sperm competition, reducing inbreeding.
- This study elucidates a postcopulatory sexual selection mechanism in field crickets.
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