Summary: The effect of sexually antagonistic selection on
adaptive sex ratio allocation
Suzanne H. Alonzo
* and Barry Sinervo
Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT and
Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, USA
Question: How is sexually antagonistic selection predicted to affect sex ratio allocation and
female mate choice?
Background: While extensive theory has examined adaptive sex allocation, no theory exists
to address the effect of sexually antagonistic selection on adaptive sex-ratio bias. We examine
this issue in the side-blotched lizard, Uta stansburiana, where females experience a trade-off
between producing high-fitness sons and high-fitness daughters.
Mathematical method: We find the evolutionarily stable female choice and sex ratio pattern
for individual females as a function of their own genotype, the genotype of their mate, and their
social environment. Data collected on the side-blotched lizard over the last decade were used to