The term for animals that can live both on land and in water is "amphibians." This class of vertebrates includes frogs, toads, salamanders, and newts. Amphibians typically undergo a life cycle that includes an aquatic larval stage, during which they breathe through gills (like tadpoles) and later transition to land as adults, developing lungs for breathing air. Their skin is permeable, allowing moisture to be absorbed; thus, they often require a moist environment to thrive. Amphibians play essential roles in ecosystems, serving as both predators and prey, and are indicators of environmental health.