Effect of Temperature on the Oxygen Consumption of Lizards from different Climatic Regions

Abstract

AbstractOxygen consumption levels and metabolic rate temperature curves of various lizard species from three different climatic regions were examined in relation to ambient temperature. The species used in this research were as follows: Anguis fragilis, Lacerta vivipara, Lacerta agilis (cool temperate species); Blanus cinereus, Podarcis hispanica, Podarcis lilfordi brauni, Podarcis lilfordi lilfordi, Podarcis muralis, Psammodromus algirus, Tarentola mauritanica (warm temperate species); Chalcides ocellatus, Acanthodactylus opheodurus, Acanthodactylus schmidti (desert species). A double chamber volumetric closed system was used to measure the resting oxygen consumption of the lizards. Acute oxygen consumption determinations were made, that is the lizards were not allowed to acclimate to the test temperatures. Interspecific differences in levels of resting oxygen consumption and in the characteristics of the metabolic rate temperature curves were examined in relation to methods of thermoregulation and in relation to the ecology of the respective species. Evidence for "temperature dependent shifts" and "low thermal dependence" was found in the metabolic rate temperature curves of some species. A diminishing Q10 at or below the voluntary body temperatures suggests some degree of metabolic homeostatsis and energy conservation.