Why do larvae and adult amphibians often use different habitats and foods?

Amphibians undergo a process called metamorphosis, which involves an abrupt and radical transformation in their physiology, anatomy, and behavior to facilitate a shift from an aquatic to a terrestrial mode of life.1

This transition necessitates changes in habitat and diet for several reasons:

• Respiratory Requirements: Larvae are typically fully aquatic and rely on gills and skin for gas exchange. As they develop into adults, gills degenerate and lungs develop, allowing them to breathe air and inhabit terrestrial environments.21
• Feeding Adaptations: Larval stages, such as tadpoles, are often herbivorous, consuming algae and plant matter in their aquatic surroundings. During metamorphosis, the digestive tract is remodeled—for instance, the intestine shortens—and adult mouthparts replace larval ones. These structural changes enable adults to transition to a carnivorous diet, typically consisting of insects and other small invertebrates.31
• Physiological Shifts: The transformation also includes changes to the urogenital system, shifting from the excretion of dilute ammonia to concentrated urea, which is better suited for life on land.1