The phrase "amphibious rodent" can refer to a unique animal that can live both on land and in water. Some synonyms for this type of creature include "aquatic rodent," "water-loving rodent," and "semi-aquatic mammal." Examples of amphibious rodents include the beaver which lives mainly in water and the nutria which lives both on land and in water. Other synonyms for these creatures include "marsh rats," "swamp rodents," and "wetland mammals." These animals have adapted to living in wet environments and have evolved unique physical characteristics to help them in their watery habitats, such as webbed feet and waterproof fur.