A new collaboration published in Plos One and led by Dr. Rudolf von May documents variation in thermal traits for nearly 60 species of frogs in a diverse lowland Amazonian community. There is a growing interest in investigating the vulnerability of tropical organisms to climate warming, yet little information is available for most species. Lowland species are thought to be at risk because they live in environments that are already hot.
We found substantial variation in tolerance to heat among species. Some species, such as the Pristimantis ockendeni of the photo, are very sensitive to temperatures just above 30°C, whereas most treefrogs and all narrow mouthed frogs (Microhylidae) tolerate much warmer temperatures. In addition to the effects of phylogeny, we assessed the contribution of life history traits and found that both critical thermal maxima and minima were correlated with species’ body size and microhabitat use. We included examination of critical thermal minima because our study system in southern Peru is exposed to cold fronts, which cause temperatures in these lowland Amazon forests to go as low as 10°C. Our data suggest that thermal physiological traits in lowland frogs are evolutionarily labile and exhibit similar rates of thermal physiological change.
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