Thermal biology of Liolaemus lizards from the high Andes: Being efficient despite adversity

VALDECANTOS MS; MARTINEZ V ; LOBO FJ; CRUZ FB

JOURNAL OF THERMAL BIOLOGY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2013 vol. 38 p. 126 - 134

0306-4565

We studied the efficiency of thermoregulation in four high elevation Liolaemus species in the Andes ofSalta, Argentina; Liolaemus irregularis, Liolaemus multicolor, Liolaemus albiceps and Liolaemus yanalcu.One of the species, L. irregularis, shows a broad distribution being in allopatry in some localities and insympatry with L. albiceps, L. multicolor and L. yanalcu at different sites. Together with this variation inassemblages, the degree of phylogenetic relatedness is different with L. irregularis being most closelyrelated to L. albiceps than to the other two species (L. multicolor and L. yanalcu). We measured body (Tb),microenvironmental (Ta, Ts), and operative temperatures (Te) in the field, and preferred bodytemperature (Tpref) in laboratory for each one of the species of assemblages. Three out of the fourspecies showed a high thermoregulatory efficiency except for L. yanalcu, a moderate thermoregulator.The species studied here show high Tb in the field compared to most of the recorded Liolaemus species.However, the Tpref values were similar to other Liolaemus species. No evidence of thermal nichesegregation between species in sympatry was observed. Our results suggest that the species studiedhere, despite living at high elevation and harsh climatic conditions are able to behaviorally orphysiologically thermoregulate to achieve Tbs close to their Tpref, probably because of low predationrisk and perhaps low levels of competition.