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Updated: Jan 6, 2026

Assessing Differences in Sperm Competitive Ability in Drosophila
Published on: August 22, 2013
Digest: Does sexual conflict complicate a trade-off between fecundity and survival?
1Department of Ecology and Evolutionary, University of Chicago, 1101 E 57th St, Chicago, Illinois, 60637.
Abstract:
Why do some species exhibit apparently suboptimal combinations of life history traits? In a comparative study of lizard species, Reedy et al. test the idea that variation in the trade-off between fecundity and survival can be explained by sexual conflict. Their results show that degree of sexual conflict alone cannot explain this variation, and they found a positive correlation between trade-off optimality and the size of males relative to females. These findings suggest a more complicated picture of the fecundity-survival trade-off, possibly involving a third, unknown source of selective pressure.
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