The Family Castoridae consists of beavers, large, primarily nocturnal rodents known for their remarkable ability to build dams, lodges, and canals in freshwater habitats. Beavers have strong, chisel-like incisors for cutting wood and a broad, flat tail used for swimming, balance, and signaling danger by slapping the water. They are herbivorous, feeding mainly on bark, leaves, and aquatic plants. As ecosystem engineers, beavers create wetlands that support biodiversity, improve water quality, and influence hydrology, making them a keystone species in North American and Eurasian environments.