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Avian Semen Collection by Cloacal Massage and Isolation of DNA from Sperm
Published on: February 5, 2018
Distinct evolutionary patterns of morphometric sperm traits in passerine birds
Simone Immler1, Alejandro Gonzalez-Voyer, Tim R Birkhead
1Department of Animal and Plant Sciences, University of Sheffield, , Western Bank, Sheffield S10 2TN, UK. mone.immler@ebc.uu.se
Proceedings. Biological Sciences
|August 17, 2012
Summary
Sperm traits like head, midpiece, and flagellum length are strongly correlated in birds. This suggests that selection acting on sperm performance, rather than just genetic links, drives their coordinated evolution.
Area of Science:
- Evolutionary biology
- Reproductive biology
- Animal morphology
Background:
- Sperm shape diversity is significant but poorly understood.
- Postcopulatory sexual selection influences sperm evolution.
- Morphometric sperm traits (head, midpiece, flagellum length) show strong positive correlations.
Purpose of the Study:
- Investigate the evolution of phenotypic correlations between sperm traits.
- Analyze allometric relationships and evolutionary trajectories of sperm traits in passerine birds.
Main Methods:
- Employed comparative methods for analyzing trait evolution.
- Compared allometric relationships and evolutionary trajectories of head, midpiece, and flagellum length.
- Focused on passerine birds.
Main Results:
- Sperm traits exhibit strong phenotypic correlations.
- Allometry of these traits varies across avian families.
- Midpiece and flagellum length share similar evolutionary trajectories; head length differs.
Conclusions:
- Phenotypic correlations between sperm traits are likely driven by concerted responses to selection.
- Selection on sperm performance and mechanistic constraints may explain correlated evolution.
- Genetic correlation and simultaneous selection are less likely explanations.
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