Courtship dynamics and factors influencing female choice of mates in zebra finches

Abstract

Extensive studies have been conducted on mate-choice and courtship behaviour in animals. It has been established that certain traits have an evolutionary advantage in terms of getting selected by the opposite sex. Previous work with the model organism, zebra finch has shown that females tend to prefer male traits such as specific song features, bright beak colour and such like. But we don’t have much clarity on the exact dynamics of the courtship ritual. Though our study we address this very question of preference establishment in female zebra finches. We conducted preference assays using live males in a choice chamber setup to explore the events that occur during preference development, the parameters that can be used to judge this preference and the factors that could influence the same. Also, we tested the effect of varying the distance between participating females and introducing a peer on a female’s preference. We found multiple parameters that can be used to judge female preference, the most robust one being the time spent next to a certain male. Next we moved on to show that preference dynamics can be described in terms of female activity, male-female interactions and evolvability of preference. Lastly, we demonstrated that reducing the distance between participating individuals or, introducing a pair female led to an increase in female activity and delay in preference establishment. Also, we found that in the presence of males, any existent social hierarchy between the females is revealed, by one female being dominant over the other. But she need not necessarily have an influence on preferences of the submissive female. Collectively, our findings paint a picture of the details involved in the process of mate-choice decision making and the influence of external conditions on female preference in zebra finches.