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Animal lifespan is determined by extrinsic and intrinsic factors causing mortality. According to the evolutionary theories of senescence, when mortality pressures are low, animals delay reproduction. This enables species to grow more slowly and, consequently, natural selection can act against harmful mutations in adulthood, thereby increasing lifespans. To test predictions of these theories we assembled a dataset on the maximum longevities and relevant ecological variables of 1320 reptilian species. Correcting for phylogeny, we modelled the link between reptile longevity and factors such as body size, microhabitat, activity period, insularity, annual temperature, temperature seasonality, elevation and clutch size that we hypothesized will affect extrinsic mortality rates and hence lifespan. Body mass explained a small proportion of the variance in reptile longevity. Species living on islands, and in colder and more seasonal environments, lived longer. Observed maximum longevity was positively associated with the number of individuals used to estimate it. Our results suggest that species exposed to reduced extrinsic and intrinsic mortality pressures (lower predation, lower metabolic rates and shorter activity periods) live longer. Sampling more individuals increases the chances of finding older specimens and should be corrected for when studying maximum longevity. [ABSTRACT FROM AUTHOR]

Aim: Longevity is a critical life‐history trait of organisms. Multiple abiotic and biotic factors are thought to exert different selection pressures, resulting in a great variation in species longevity. We examined factors that, according to evolutionary theories of senescence, are thought to be related to extrinsic and intrinsic mortality rates, and thus shape the variation in longevity among amphibians. Location: World‐wide. Time period: Present. Major taxa studied: Amphibia. Methods: We collected literature data on the maximum longevities of 527 amphibian species. Correcting for phylogeny and sample size, we modelled the relationship between amphibian longevity and body size. We also examined the effects of chemical protection, activity period, microhabitat preferences and annual temperature on amphibian longevity. Results: In general, members of larger amphibian species live longer. Body size, however, explained less of the variation in amphibian longevity than it does in mammals and birds. Nocturnal amphibians, species that use poison for defence and those inhabiting cold regions live longer, but microhabitat preferences had little effect. Main conclusions: Our results supported predictions of evolutionary theories of senescence. Large amphibians living in colder environments probably experience slower growth and metabolic rates, reducing intrinsic drivers of mortality and increasing longevity. Moreover, species that reduce extrinsic mortality pressures via chemical protection and nocturnality have increased longevity. Sampling captive animals and sampling more individuals of a species increases the chances of finding older individuals and should be corrected for when studying maximum longevity. [ABSTRACT FROM AUTHOR]