Male mate choice based on female coloration in a lizard: the role of a juvenile trait

Female mate choice for male display traits is widely observed across animal taxa and is a well-established mechanism of evolution. However, males are increasingly seen to exhibit mate choice for female display traits, even in species with traditional sex roles, although this continues to be an understudied aspect of sexual selection. We evaluated the role of female coloration on male mate choice decisions in the spiny-footed lizard (Acanthodactylus erythrurus), a species in which adult females show red coloration as a retained juvenile trait. While both sexes show red tails as juveniles and subadults, only females maintain red colored tails when becoming adult; moreover, this coloration is only present at the beginning of female adulthood and becomes white after ovulation, suggesting a mating-related function. Male courtship preferences were investigated through an experimental approach, where they were offered pairs of females that differed in size (adult/subadult) and tail coloration ...雌性对雄性展示性状的配偶选择在诸多动物类群中被广泛观测到，是一项已得到充分证实的进化机制。然而，即便在具有传统性别角色的物种中，雄性也愈发频繁地表现出对雌性展示性状的配偶选择——尽管这一方向仍是性选择研究中未被充分探索的领域。本研究以棘趾蜥（Acanthodactylus erythrurus）为研究对象，评估了雌性体色对雄性配偶选择决策的影响。该物种的成年雌性会将红色体色作为幼态保留的性状：幼体与亚成体阶段的雌雄个体均长有红色尾部，但仅雌性在成年后仍保留红色尾部；此外，该红色体色仅存在于雌性成年初期，排卵后会褪为白色，提示其可能具备与交配相关的功能。研究通过实验范式探究雄性的求偶偏好，为雄性提供了在体型（成年/亚成体）与尾部体色上存在差异的雌性配对……