Distribution and Viviparity in Liolaemus species: climate and when hypotheses need to be tested

Abstract

Cruz, F.B., Moreno Azócar, D.L., Bonino, M.F., Schulte II, J.A., Abdala, C.S., Perotti, M.G. 2014. Climate, geographic distribution and Viviparity in Liolaemus (Reptilia; Squamata) species: when hypotheses need to be tested. Ecosistemas 23(1):37-45. Doi.: 10.7818/ECOS.2014.23-1.06

Reptile’ distributions, under the light of their strong dependence on particular temperature requirements, may be constrained as a consequence of climate. The relationship between reptile viviparity and climate yielded two previously proposed hypotheses (the cold climate and the maternal manipulation hypotheses) that together with the climatic variability hypothesis; theoretically link climate and reproductive mode. The extensive variation in mean environmental temperature associated with changes in parity strategies has received much attention in this ectothermic group. Among Southamerican lizards, Liolaemus are distributed in cold and warm regions and more than 50 % of described species are viviparous. We studied 47 Liolaemus species considering climatic data where collected, preferred body temperature, its coefficient of variation and their thermal tolerance. Our results do not support the climate variability hypothesis, previously supported in other studies. We found a relationship between viviparity and elevation, but not between viviparity and thermal climatic variables. Finally, viviparous Liolaemus species showed more precise thermoregulatory behavior than oviparous ones, supporting the maternal manipulation hypothesis.