Multiple colour traits signal performance and immune response in the Dickerson’s collared lizard Crotaphytus dickersonae
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Conspicuous male coloration is often an honest signal of individual quality. In Dickerson’s collared lizard (Crotaphytus dickersonae), males are striking blue, have a black and white collar and have white spots on their bodies. In this study, we investigated whether this extravagant colour pattern is an indicator of male performance in variables related to resource-holding power (bite force, running speed and endurance) and immune condition (cellular response and ectoparasite load). Also, we assessed direct and indirect effects of testosterone levels and body temperature on colour traits. We found that males with bluer skin, and darker and bigger black collars performed better in variables related to resource-holding power. Also, the black colour of the collar was related to immune condition. Blue chroma was positively related to temperature, yet males with bigger and darker black collars had lower body temperatures. Testosterone had minor effects on immune response and colour traits. Our results suggest that multiple colour traits in the Dickerson’s collared lizard may honestly indicate physical and physiological performance.
KeywordsHonest signal Coloration Temperature Testosterone Immune condition Resource-holding power
We thank Víctor E. Argaez Márquez, Gala E. Castro Mejías, Abigail Vera Ortega, Paola Flores Mejía and J. Alberto Cruz Silva for their help in the field. Lorayne Meltzer facilitated accommodation and space for field experiments at Prescott College Kino Bay station. We thank Diego Carmona Moreno Bello for his enthusiastic advice with the pathway analyses, Laura García Rivera and Natalia Gañan for their help with the testosterone analysis, and Ricardo Paredes León for the determination of the ectoparasites. We thank Alejandro Córdoba Aguilar and Andrés García Aguayo for their comments on earlier drafts of this paper. Financial support was provided by the Universidad Nacional Autónoma de México (UNAM, PAPIIT IN206713). Specimens were captured and released under collection permit SGPA/DGVS/03365/12 granted by Secretaría del Medio Ambiente y Recursos Naturales to RT. M. Plasman thanks the Consejo Nacional de Ciencia y Technología (CONACyT) for her PhD studies grant. This paper is a partial fulfilment for MP’s doctoral degree, Posgrado en Ciencias Biológicas, UNAM.
The study complies with the current regulations of Mexico regarding animal welfare.
Conflict of interest
The authors declare that they have no conflict of interest.
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