Ecologia térmica de anuros de altitude na Mata Atlântica: avaliando efeitos da altitude, térmica do ambiente e da performance sob diferentes temperaturas

Abstract

Thermal ecology studies how ecosystems and their organisms can be influenced by environmental temperature. Temperature is a factor that affects all individuals, however, ectothermic organisms such as amphibians are more sensitive, since their body temperature depends on the environment temperature to which they are subjected. In order for these organisms to perform some physiological functions satisfactorily, they must have their body temperature within an optimal temperature range in which their physiological performance is potentiated. Among ectothermic vertebrates, although much attention has been given to reptiles in the last seven decades, very few studies and understanding exist when it comes to amphibians thermal ecology. In the present study, we sought to understand the thermal physiology aspects of anurans from mountainous regions of Atlantic Forest, seeking to know more about the aspects of the influence of environment temperature. In these regions, large temperature fluctuations occur daily and anurans are the most sensitive group to broad temperature shifts. Thus, the first chapter discussed about how the environment temperature and body mass influenced the body temperature of the studied individuals in the Itatiaia National Park and the Serra dos Órgãos National Park. The second chapter seeked to evaluate the thermal physiology of three species of the genus Ischnocnema, whose individuals were studied in the Serra dos Órgãos National Park, highlighting not only their body temperatures, but also other parameters of thermal physiology, such as their preferred temperature, minimum and maximal voluntary temperatures. In addition, a performance curve at different temperatures was designed for the three studied species in this chapter. In this study, the environment temperature was the greatest factor influencing on the body temperature of the studied anurans, and was suggested to be the key factor in the distribution of the species