Geography, Temperature, and Water: Interaction Effects in a Small Native Amphibian

Area of Science:

• Zoology
• Ecology
• Physiology

Background:

• Amphibian locomotor capacity is influenced by temperature and hydration.
• Environmental factors often covary, necessitating studies on their interactive effects.
• Geographic variation can lead to population-specific adaptations.

Purpose of the Study:

• To evaluate the thermal and hydric sensitivities of locomotor performance in *Pleurodema thaul*.
• To compare these sensitivities between populations from contrasting thermal and precipitation environments.
• To understand the potential for geographic variation in physiological responses.

Main Methods:

• Selected two populations of *Pleurodema thaul* from contrasting environments.
• Assessed locomotor performance under varying temperature and hydration conditions.
• Analyzed the sensitivities and potential interactive effects of these factors.

Main Results:

• Locomotor performance increased with both temperature and hydration, plateauing between 25°C and 30°C.
• The impact of dehydration on performance was consistent across tested temperatures.
• The population from the warmer environment exhibited reduced sensitivity to dehydration.

Conclusions:

• Temperature and hydration are key determinants of amphibian locomotor performance.
• Geographic variation may lead to adaptive differences in physiological responses to environmental stress.
• Further research is needed to fully elucidate the mechanisms of thermal adaptation in *Pleurodema thaul*.