Locomotor performance of cane toads differs between native-range and invasive populations

Area of Science:

• Ecology
• Evolutionary Biology
• Animal Physiology

Background:

• Invasive species present unique opportunities to study adaptation to new environments.
• Locomotor performance is crucial for dispersal and invasion success, and is influenced by environmental factors like temperature and hydration.
• Understanding these factors is key to predicting and managing invasive species spread.

Purpose of the Study:

• To investigate geographical variation in locomotor performance of invasive cane toads (Rhinella marina).
• To assess how thermal and hydric constraints affect cane toad populations across native and invasive ranges.
• To determine if invasive populations have evolved enhanced locomotor abilities and resilience.

Main Methods:

• Studied cane toads from native Brazil, invasive Hawai'i, and multiple invasive Australian populations.
• Measured locomotor performance on a circular raceway under varying temperature and hydration conditions.
• Compared performance metrics across populations to identify geographical divergences.

Main Results:

• Cane toad locomotor performance was significantly affected by temperature and hydration, with population-specific differences.
• Toads from the native range showed lower performance and greater sensitivity to environmental extremes.
• Invasive populations, particularly in southern Australia, displayed enhanced performance and resilience to dehydration and cold.

Conclusions:

• Geographical variation in locomotor performance highlights the adaptability of invasive species.
• Invasion success may be linked to evolved enhancements in locomotor performance and environmental tolerance.
• Cane toads demonstrate significant adaptive capacity when facing novel abiotic challenges in new environments.