What key feature differentiates amphibians from reptiles in freshwater environments?

Amphibians are distinguished from reptiles primarily by their unique life cycle, which involves metamorphosis and transitions between aquatic and terrestrial environments. During their early development, amphibians such as frogs and salamanders begin life as aquatic larvae, often possessing gills for breathing underwater. As they mature, these organisms undergo metamorphosis, transforming into adults that can live on land and breathe through lungs, skin, or both.

This dual life cycle provides amphibians with adaptability to different habitats, allowing them to exploit ecological niches in both freshwater and terrestrial environments. The ability to thrive in both settings is a critical aspect of their biology and reproductive strategy. Reptiles, in contrast, have a more straightforward life cycle that does not include aquatic larval stages, and they generally reproduce by laying eggs on land, which is a significant aspect of their adaptation to terrestrial life.