Mate choice and evolutionary genetics in Xiphophorus hybrid zones

Texas A&M Research Foundation, College Station TX

Investigators

Abstract

Choosing a mate is one of the most far-reaching decisions an animal can make. A female's mate choice can influence not only which male traits get passed on to the next generation, but also the formation of new species or the fusion of two species through hybridization. Mating preferences are complex, with females paying attention to numerous different male characteristics, and females often prefer male trait combinations never found in nature. How do complicated female mating preferences drive male trait evolution? This project takes advantage of remarkable natural hybrid zones between two species of swordtail fish in the Sierra Madre Oriental of central Mexico. Males of the two species are strikingly different in physical appearance, and females of the two species show strong differences in their preferences for male characters. Mating preferences for multiple male traits will be evaluated by presenting females with computer-animated clips of males. Genetic mapping will be used to identify which sets of genes are associated with male traits and female preferences. This genetic information will then be used to test how traits and preferences are associated in the wild. This project will directly connect the psychology of mate-choice decisions with the evolutionary consequences of these decisions. The project will sustain collaboration with Mexican researchers, mentoring of minority undergraduates, and conservation, sustainable development, and outreach efforts in rural Mexico.