The beaver (genus Castor) is a large, primarily nocturnal, semiaquatic rodent. Castor includes Beavers continue to grow throughout their lives. Adult specimens weighing over 25 kg (55 lb) are not uncommon. Females are as large as or.
The coypu also known as the nutria, is a large, herbivorous, semiaquatic rodent. Classified for a Literally, therefore, the name Myocastor means "beaver rat". . Being one of the world's larger extant rodents, a mature, healthy coypu averages .
Beaver, (genus Castor), either of two species of amphibious rodents native to North Adult beavers and kits (Castor canadensis) in the Rocky Mountains.
The phrase "busy as a beaver" aptly describes these big-toothed rodents that can change the landscape and their environment.