Dynamic dichromatism and effects of high temperatures on male coloration plasticity in an ectotherm model

ROSSI, NICOLA; CHIARAVIGLIO, MARGARITA; CARDOZO, GABRIELA

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2024

0024-4066

Climatechange is increasing the temperatures of wild environments but theimpacts onevolutionaryecological processes like sexual selection are still understudied. Inectotermic tetrapods, male coloration is a pivotal trait in socialcontexts. Indeed during the reproductive season, males can enhancethe dichromatic colouration of certain body regions. However, it isunknown how reproductive dichromatism might interact with theincreasing temperatures that cause body temperatures to fall withinthe upper set of preferred temperatures. We hypothesize that sexualdichromatism could be dynamic, i.e. show changes, being reinforcedduring the reproductive period of the species. However, hightemperatures associated to climate change could disrupt reproductivecolour patterns by inducing plastic changes. We test this in thesocial lizard species Tropidurusspinulosus byapplying in a laboratory setup three thermal treatments, onereproducing current thermal condition and two simulating scenarios ofclimate change. Our results highlight that male colouration isenhanced during the reproductive season in key body regions forsocial displays. At the preferred temperature of the species, malescould darken their ventral colouration, however no such change wasobserved at high temperatures. Therefore, increasing temperaturescould impact on males capacity to plastically adjust theircolouration during the reproductive season.