INIBIOMA   20415
INSTITUTO DE INVESTIGACIONES EN BIODIVERSIDAD Y MEDIOAMBIENTE
Unidad Ejecutora - UE
artículos
Título:
How and when melanic coloration is an advantage for lizards: the case of three closely-related species of Liolaemus
Autor/es:
PEROTTI, MARÍA GABRIELA; ARCOS, NAYAN ANDALUZ; MORENO AZÓCAR, DÉBORA LINA; CRUZ, FÉLIX BENJAMÍN
Revista:
ZOOLOGY
Editorial:
ELSEVIER GMBH
Referencias:
Año: 2020
ISSN:
0944-2006
Resumen:
Body temperature affects various aspects of ectotherm biology. Reptiles, as ectotherms, gain and control theirtemperature mainly through behavioural adjustments, although some body traits may also be advantageous. Accordingto the thermal melanism hypothesis (TMH) dark colour may be thermally advantageous in cold environments.Additionally, differences in thermoregulatory capacity may also affect performance. We analysed therole of melanism in the thermoregulation and sprint speed performance of three species of Liolaemus lizards fromArgentinean Patagonia. Liolaemus shitan, L. elongatus and L. gununakuna are phylogenetically close, with similarbody sizes and life history traits, but differ in their melanic colouration, L. shitan being the darkest and L. gununakunathe lightest species. We estimated sprint speed performance curves and heating rates, and recordedfinal body temperature and sprint speed achieved after a fixed heating time, from two different initial body temperatures,and with and without movement restriction. Performance curves were similar for all the species, butfor L. gununakuna the curve was more flattened. Darker species showed faster heating rates, ran faster after fixedheating trials at the lowest temperature, and reached higher body temperatures than L. gununakuna, but this wascompensated for by behavioural adjustments of the lighter lizards. Similarity of sprint speed performance may bedue to the conservative nature of this character in these species, while variation in heating ability, particularlywhen starting from low temperatures, may reflect plasticity in this trait. The latter provides support for the TMHin these lizards, as melanism helps them increase their body temperature. This may be especially advantageousat the beginning of the day or on cloudy days, when temperatures are lower.