Sequential mate choice by multiply mating smooth newts: females become more choosy

In some species, females sequentially mate with different males within a single mating period, store sperm until the eggs are eventually fertilized, and gain no other resources from the males. Halliday hypothesized that, for such species, a female could ensure fertilization of her eggs by mating with the first male that she encounters; thereafter, she can maximize the quality of her progeny by sampling further males and by mating only with males of higher quality than previously mated males. This hypothesis predicts that females ' choosiness will increase as the breeding season progresses. We tested this prediction of Haffi-day's hypothesis by examining mate choice by female smooth newts (THturui vuigaris vuigaris). Males of this species develop a dorsal crest during the courtship season. Crest height varies between males and is potentially an indicator of male quality. Initially, female smooth newts were equally willing to mate with males with low or high crests. However, in their second mating, females remated only with high-crested males. These results support our prediction and are consistent with HaOiday's hypothesis. If crest height in smooth newts is an indicator of quality, this change in females ' mate choice criterion allows females both to initiate egg-laying very early in the season and, subsequently, to mate preferentially with higher quality mates. Kty toords: female choice, multiple mating, sequential mate choice, sexual selection, smooth newts, THturui vuigaris. [Behav Ecd 8:162-16