Demography of Xenosaurus platyceps (Squamata: Xenosauridae): a comparison between tropical and temperate populations

Abstract

There appears to be variation in life-history strategies even between populations of the same species. For ectothermic organisms such as lizards, it has been predicted that demographic and life-history traits should differ consistently between temperate and tropical populations. This study compares the demographic strategies of a temperate and a tropical population of the lizard Xenosaurus platyceps. Population growth rates in both types of environments indicated populations in numerical equilibrium. Of the two populations, we found that the temperate population experiences lower adult mortality. The relative importance (estimated as the relative contribution to population growth rate) of permanence and of the adult/reproductive size classes is higher in the temperate population. In contrast, the relative importance for average fitness of fecundity and growth is higher in the tropical population. These results are consistent with the theoretical frameworks about life-historical differences among tropical and temperate lizard populations.

Ecología térmica de dos especies de lagartijas del género Xenosaurus (Squamata: Xenosauridae) en México

“…Keywords: Thermoconformer; Thermoregulation; Reproductive stage; Knob-scaled lizard; Puebla; Veracruz https://doi.org/10. 22201/ib.20078706e.2019.90.2650 Woolrich-Piña et al, 2012), demografía (Lemos-Espinal et al, 2003a;Rojas-González, Jones et al, 2008;Zamora-Ábrego et al, 2010), historia natural (Lemos-Espinal y Smith, 2005), crecimiento (Zúñiga-Vega et al, 2005), reproducción Zamora-Ábrego et al, 2007;Zúñiga-Vega, 2011), dieta, dimorfismo sexual (García-Rico et al, 2015), ecología térmica (Gadsden y Woolrich-Piña, 2017; García-Rico et al, 2015) y evolución (Bhullar, 2010(Bhullar, , 2011Canseco-Márquez, 2005;Nieto-Montes de Oca et al, 2017. Sin embargo, las poblaciones tienen una distribución fragmentada y se requiere con premura más información de la ecofisiología de las especies de este género, que permita el mejor entendimiento de las estrategias de termorregulación que presentan distintas especies en diferentes hábitats y épocas del año, de manera que este conocimiento oriente los planes sobre la conservación de poblaciones potencialmente vulnerables (Ballinger et al, 2000).…”