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Measuring Sperm Guidance and Motility within the Caenorhabditis elegans Hermaphrodite Reproductive Tract
Published on: June 6, 2019
By hook or by crook? Morphometry, competition and cooperation in rodent sperm
Simone Immler1, Harry D M Moore, William G Breed
1Department of Animal and Plant Sciences, University of Sheffield, Sheffield, United Kingdom. s.immler@sheffield.ac.uk
Plos One
|January 25, 2007
Summary
Rodent sperm hooks aid in sperm competition. Species with larger testes exhibit longer sperm hooks, suggesting sperm cooperation is common in rodents and influences sperm design evolution.
Area of Science:
- Evolutionary biology
- Reproductive biology
- Animal behavior
Background:
- Sperm design varies greatly across species, influenced by sperm competition.
- The functional significance of many sperm traits remains unclear.
- Murid rodent sperm typically have an apical hook, with varying degrees of reflection.
Purpose of the Study:
- To investigate the role of the apical sperm hook and sperm cooperation in rodent sperm competition.
- To determine if sperm cooperation is a widespread adaptation in rodents.
Main Methods:
- Comparative study of murine rodent sperm.
- Analysis of the relationship between testes size and apical sperm hook morphology.
Main Results:
- A longer, more reflected apical sperm hook is associated with larger testes, indicating more intense sperm competition.
- Sperm grouping (cooperation) was observed in rodent species beyond the European woodmouse.
Conclusions:
- Sperm cooperation appears to be a widespread adaptation in rodents, more common than previously thought.
- The findings underscore the significance of diploid versus haploid selection in shaping sperm evolution.
