Reproductive Phenology, Distribution and Climate Change in Viviparous Phrynosoma: Implications for the Future Thermal Refugia
Mendez de la Cruz, Fausto R.
Arenas-Moreno, Diego Miguel
Instituto de Biología
UNAM Rafael Lara Resendiz CIBNor
Distribution of viviparous lizards are restricted to México or close to the Mexican borders, the only viviparous lizards that reach north of USA and south of Canada belongs to Elgaria or Phrynosoma. Phrynosoma lizards from the tapaja clade presented a northern to central distribution and are considered spring-summer breeders, whereas the brevicauda clade presents a southern distribution and were considered fall breeders. In this study we analyze the reproductive phenology, thermal quality and vulnerability to climate change (Mapinguari R package). We found that P. sherbrookei (brevidcauda clade) is spring-summer breeder, which is related to thermal quality of the environment. The pregnancy period could last from 2.5 months to 10-11 depending on the thermal quality of the environment. As pregnant females of Phrynosoma may reach temperatures higher than 35ºC, they may develop the embryos faster (2.5 months or slower (10-11 months), depending on the thermal quality of the environment, and unrelated to the phylogeny. Therefore are the only viviparous lizards that could deal with 6-7 months of activity per year in USA or Canada. On the other hand, populations that are closer to the Equator are considered more vulnerable to climate change, in this study we found that northern populations presents a lower thermal quality due to high temperatures and are more vulnerable to climate change, whereas the southern populations presents lower thermal quality due to low temperatures, in fact must be active at suboptimal temperatures. The mountains of Mexico represent thermal refugia in the future scenarios of climate change.