Supplementation of Male Pheromone on Rock Substrates Attracts Female Rock Lizards to the Territories of Males: A Field Experiment

José Martín,Pilar López,Graeme Clive Hays

doi:10.1371/journal.pone.0030108

Abstract

BackgroundMany animals produce elaborated sexual signals to attract mates, among them are common chemical sexual signals (pheromones) with an attracting function. Lizards produce chemical secretions for scent marking that may have a role in sexual selection. In the laboratory, female rock lizards (Iberolacerta cyreni) prefer the scent of males with more ergosterol in their femoral secretions. However, it is not known whether the scent-marks of male rock lizards may actually attract females to male territories in the field.Methodology/Principal FindingsIn the field, we added ergosterol to rocks inside the territories of male lizards, and found that this manipulation resulted in increased relative densities of females in these territories. Furthermore, a higher number of females were observed associated to males in manipulated plots, which probably increased mating opportunities for males in these areas.Conclusions/SignificanceThese and previous laboratory results suggest that female rock lizards may select to settle in home ranges based on the characteristics of scent-marks from conspecific males. Therefore, male rock lizards might attract more females and obtain more matings by increasing the proportion of ergosterol when scent-marking their territories. However, previous studies suggest that the allocation of ergosterol to secretions may be costly and only high quality males could afford it, thus, allowing the evolution of scent-marks as an honest sexual display.

Highlights

Many animals produce elaborated sexual signals, which in many cases are intended to attract potential mates [1]
Attraction of females to sexual signals of males may be mainly explained because these signals provide honest information about the characteristics of males [2], or because the signal exploits the sensory system of females that have a sensory bias for some traits [3,4]
Chemoreception is, the main sensory system used by many animals, and chemical signals play an important role in the intraspecific communication and sexual selection of many types of animals, including vertebrates [5,6,7]

Summary

Introduction

Many animals produce elaborated sexual signals, which in many cases are intended to attract potential mates [1]. Attraction of females to sexual signals of males may be mainly explained because these signals provide honest information about the characteristics of males [2], or because the signal exploits the sensory system of females that have a sensory bias for some traits [3,4]. In any case, these male sexual signals can evolve by sexual selection to increase their attractiveness to females. Lizards produce chemical secretions for scent marking that may have a role in sexual selection. It is not known whether the scent-marks of male rock lizards may attract females to male territories in the field

Methods

Results

Conclusion