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Updated: May 2, 2026

Assessing Differences in Sperm Competitive Ability in Drosophila
Published on: August 22, 2013
Covariance between testes size and substitution rates in primates
1Department of Biology, Carleton University, Ottawa, Ontario, Canada alex.wong@carleton.ca.
Abstract:
Understanding the causes of substitution rate variation is an important goal in the study of molecular evolution. It has been proposed that sperm competition intensity may affect genome-wide rates of substitution as a by-product of selection on sperm numbers. Here, I test this hypothesis by applying recently developed Bayesian methods to a data set consisting of approximately 35 kb of sequence data from 55 primate species. I find evidence for positive covariance between testes mass and the rate of substitution, independently of the potentially confounding effects of body mass and longevity.
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