Beavers

Beavers inhabit ponds and streams in wooded areas from Alaska to northern Mexico. Their bodies are ideally constructed for their varied activities on land and the water. A beaver’s large hind feet are webbed for swimming. His broad, flat tail is scaly and naked, except for a few bristles. It seves as a prop when he stands up to gnaw on tress; it becomes an alarm signal when slapped against the water; it is rudder and an oar when he is swimming.
Though air breathers, beavers are troughly at home in the water. They can remain submerged for 15 minutes at a time. When a beaver dives, flap-like valves in his ears and nostrils close, shutting out the water. Except for his tail, the beaver is clothed in a shiny coat of soft, thick underfur; this is overlaid with longer, coarser guard hairs. Glands on either side of the tail supply oil, which keeps the coat waterproofed and glistening. The two inner claws of the beaver’s hind feet are grooved; they make efficient combs for grooming the coat and spreding the oil through it.