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Aim: Squamate fitness is affected by body temperature, which in turn is influenced by environmental temperatures and, in many species, by exposure to solar radiation. The biophysical drivers of body temperature have been widely studied, but we lack an integrative synthesis of actual body temperatures experienced in the field, and their relationships to environmental temperatures, across phylogeny, behaviour and climate. Location: Global (25 countries on six continents). Taxa: Squamates (210 species, representing 25 families). Methods: We measured the body temperatures of 20,231 individuals of squamates in the field while they were active. We examined how body temperatures vary with substrate and air temperatures across taxa, climates and behaviours (basking and diel activity). Results: Heliothermic lizards had the highest body temperatures. Their body temperatures were the most weakly correlated with substrate and air temperatures. Body temperatures of non‐heliothermic diurnal lizards were similar to heliotherms in relation to air temperature, but similar to nocturnal species in relation to substrate temperatures. The correlation of body temperature with air and substrate temperatures was stronger in diurnal snakes and non‐heliothermic lizards than in heliotherms. Body‐substrate and body‐air temperature correlations varied with mean annual temperatures in all diurnal squamates, especially in heliotherms. Thermal relations vary with behaviour (heliothermy, nocturnality) in cold climates but converge towards the same relation in warm climates. Non‐heliotherms and nocturnal species body temperatures are better explained by substrate temperature than by air temperature. Body temperature distributions become left‐skewed in warmer‐bodied species, especially in colder climates. Main Conclusions: Squamate body temperatures, their frequency distributions and their relation to environmental temperature, are globally influenced by behavioural and climatic factors. For all temperatures and climates, heliothermic species' body temperatures are consistently higher and more stable than in other species, but in regions with warmer climate these differences become less pronounced. A comparable variation was found in non‐heliotherms, but in not nocturnal species whose body temperatures were similar to air and substrate irrespective of the macroclimatic context. [ABSTRACT FROM AUTHOR]

Montane animals require different adaptations than lowland species because of more severe conditions. Proctoporus lizards of the Andes Mountains experience cold temperatures year‐round, which may affect their activity. Two species of this poorly known genus, P. unsaacae and P. sucullucu, have similar morphology and ecology, but had never been studied in detail. The purpose of this project was to compare the population biology of the two species and to ascertain whether they were more likely to share ecological similarities with phylogenetic relatives or with other unrelated lizards of the Andes. We established two permanent plots in the Sacred Valley of the Incas in Cusco region, Peru, and examined the thermal ecology, movement, sex ratio, longevity, population sizes, growth patterns, reproduction and other factors over a period of 4 years. Proctoporus unsaacae and P. sucullucu were similar in most aspects of their ecology except that P. sucullcu was larger, had smaller population sizes, and fewer recaptures. Both species live exclusively under rocks and are strict thermoconformers who do not actively thermoregulate their body temperatures by basking, as other high Andean lizards do. The two species have reverse sexual dimorphism with P. unsaacae having larger females and P. sucullcu having larger males. The species are highly philopatric with average movement of less than 7 m in a lifetime. Both appear to be relatively long‐lived with an individual P. unsaacae living longer than 2 years 8 months. At both sites, populations age structures had few juveniles and we detected a declining population of P. unsaacae in Urubamba. This project lays the groundwork for more in‐depth studies of the ecology of both species and their high‐elevation habitats. [ABSTRACT FROM AUTHOR]

A personal narrative is presented which explores the author's experience of being attended my first herpetological meeting in 1993 after completing my Bachelor's degree and before my Master's program had begun.