Thermal Adaptations in Tropical Andean Amphibians: Exploring Spatial Variability and Global Change Impacts

In the tropical Andes, stable climatic zonations with elevation act as potential thermal barriers, limiting species’ vertical migration and fostering specialized thermal niches. This chapter provides comprehensive insights into the interplay of elevational gradients, microclimatic conditions, and biotic interactions, which shape the thermal niches determining the distribution ranges and climatic risk patterns of tropical Andean amphibians. Elevational patterns of thermal tolerances reveal that high-elevation species exhibit differential cold tolerances, yielding broader thermal niches due to greater thermal variability in minimum temperatures. Microenvironment matters, forest and stream frog communities have narrower thermal tolerance breadths compared to species in open and pond habitats, determining that thermally buffered forest microhabitats are particularly vital in regions experiencing rapid land-use changes. Moreover, biotic interactions, such as predation, are crucial in thermal physiology. For instance, predatory dragonfly larvae exhibit higher heat tolerances than their sympatric amphibian prey, which may lead to increased predation pressure as global temperatures rise. Regarding climatic risk, the static elevational pattern of heat tolerance poses a significant challenge, particularly for lowland species that are nearing their upper thermal limits. While high-elevation species may benefit from a warming climate due to inhabiting suboptimal thermal conditions, they could also face negative biotic interactions such as increased predation and the detrimental effects of current emergent fungal diseases, which could further constrain their distribution.