Thermal biology of genus Liolaemus: A phylogenetic approach reveals advantages of the genus to survive climate change

Abstract

The trends of body temperatures in the field (Tb) and preferred body temperatures in the laboratory (Tpref) of the genus Liolaemus relative to reproductive mode, air temperature (Tair), precipitation, latitude, and elevation were studied using phylogenetic comparative analysis. Results were discussed in the framework of the evolution of thermal physiology and vulnerability to global climate change. Reproductive mode affects Tb but not Tpref. Whereas Tb and Tpref showed a significant association with Tair, there was no relationship with latitude or elevation. In most liolaemids, Tpref is significantly higher than Tair and Tb pointing to a primitive condition of Tpref, probably related to earlier Miocene environments. Phylogenetic trends in the evolution of liolaemid thermal physiology provide a physiological explanation for the lowest rates of observed contemporary climate-forced extinctions and those forecasted under climate warming scenarios up to 2080. Liolaemids have a much higher Tpref than is expected for their environments, especially for viviparous members of the genus, in contrast to other viviparous taxa in the sister family the Phrynosomatidae, which have evolved much lower Tb (and Tpref) and currently experience a much higher rate of climate-forced extinction.