Description | Description:Beavers are brown or grey nocturnal animals which build dams in rivers, using sticks, leaves, and mud. They are great in the water, but slow on land, and will slap their flat tails on the water as a sign and warning of distress. | Description:Mexican Prairie dogs live only in the grassland valleys of Mexico. They have mouse-like ears and blunt noses, and usually develop and thicken their fur during winter. Their large auditory glands can pick up sounds ranging from 29 to 26,000 Hz. |