Dance or disappear: Strategic sexual signalling in Peninsular rock agama

Abstract

Sexual signalling has largely been studied in the context of indirect competition among males through displays and mate choice by females. Historically, sexual signalling in females was expected to be of limited consequence. However, there is growing evidence of sexual signalling in females and its value in the context of sexual selection. Here, we test how females strategize the use of sexual signals in a socially polygynous lizard, Psammophilus dorsalis. We evaluated key hypotheses for how females should modulate their signalling, including male quality and mate availability. We simulate male quality using artificial male models to individually tagged, and intensely monitored wild female lizards, measuring their strategic investment in sexual signalling. We found that females invest more in signalling towards high quality males and increased their investment towards the later part of the only breeding season. Contrary to what is typically expected in a polygynous mating system, females not only invest in costly and elaborate sexual signals, they also modulate their usage to maximise their benefits and minimise their costs. Even in polygynous mating systems, dispersed distribution of individuals can result in females experiencing limitation in mate availability, resulting in costly sexual signalling.