Mate Assessment and Non-Independent Mate Choice by Female Japanese Quail

Abstract

<p>The body of this thesis is comprised primarily of two published papers (Chapters 2 and 3) and a third paper (Chapter 5) accepted for publication. All three investigate the influence of social information on mate choice in female Japanese quail, Corturniz japonica.</p> <p>In Chapter 1, I review the theoretical and empirical literature on mate choice and eavesdropping that are relevant to the main topics with which this thesis is concerned. I demonstrate, in Chapter 2, that female Japanese quail use information garnered from video images of males interacting with other females when subsequently choosing between the live males that appeared in the videos. The results of this experiment provide evidence of the utility of a technique to investigate social influences on the behavior of Japanese quail, and possibly, other avian species as well.</p> <p>In Chapter 3, I show that females use social information acquired by observing inter-male aggression to select mates, and provide evidence that the threat of injury posed by aggressive males influences females to select less aggressive males as mates. In Chapter 4, I provide a control for the possibility that females were not actually choosing to stay near less aggressive males in the experiments described in Chapter 3, but were preferring locations where those males had been seen engaged in agnostic interaction. Finally, in Chapter 5, I examine the role of sexual experience in determining whether when selecting a mate female quail copy the mate choices of other females or attend to the relative aggressiveness displayed by males engaged in intra-sexual competition when selecting a mate. I report that prior sexual experience is necessary for females to avoid the more aggressive of two males but not for expression of mate-choice copying. Taken together, the results of Chapters 3, 4 and 5 are consistent with the hypothesis that the relative costs and benefits of associating with dominant and submissive males may determine which type of male females will prefer as a partner. The view that females should invariably prefer dominant males because such males are likely to be a source of superior genes or can provide females with greater resources considers only the benefits and not the potential costs to females of consorting with relatively aggressive males.</p> <p>In Chapter 6 I summarize the major findings of the thesis, and then briefly describe a failed experiment to determine whether the technique developed in Chapter 2 could be used to examine effects of female observation of inter-male aggression on subsequent mate choice in the absence of audience effects, and discuss the conflicting selection pressures that Japanese quail of either sex may face.</p>