If you're wondering why beavers teeth are orange, it isn't staining from their environment--it's actual iron in their tooth enamel. As you might expect, that iron makes their teeth stronger and better able to cut through wood.

Using its webbed hind feet for propulsion and its flat tail as a rudder, a beaver can swim up to 6 miles an hour. It can also hold its breath underwater for up to 15 minutes, helping it to avoid predators.

Beavers create dams to slow the flow of a river or stream, which results in the formation of a pond, their favorite place to live.

Domelike beaver homes, called lodges, are constructed of branches and mud. In order to protect themselves from predators, beavers strategically locate their lodges in the middle of ponds and make them accessible only by underwater entrances.

Perhaps the most distinctive feature of the beaver is its flat, scaly tail, which acts as a rudder when swimming and maneuvering underwater. On dry land, the tail acts as a prop, allowing the beaver to sit upright, or as a counterbalance so he doesn't tip over while carrying heavy supplies in his teeth. If a beaver feels threatened, it will slap its tail on the surface of the water to warn other beavers in the area. Contrary to popular belief, beavers do not use their tails to pack or carry mud.

Castoreum is a yellowish exudate from the castor sacs of mature beavers. It is secreted as a brown slime that's about the consistency of molasses and smells like musky vanilla. Although it is no longer widely used in vanilla extract, it is still an FDA-approved natural flavoring.

Beavers have large teeth that never stop growing. Chewing on tree trunks and branches helps keep their teeth from getting too long.

Beaver dams typically range in length from a few meters to perhaps 100 meters (330 ft), but the world's largest beaver dam, located at the lip of Wood Buffalo National Park in Alberta, Canada, is at least 850 meters (2,790 ft) long. It is so large that it can be seen from space. Ecologists believe beavers built the dam over the course of three decades.

Beavers form monogamous pairs and usually live in family groups of up to 8 related individuals called colonies. The younger siblings stay with their parents for up to 2 years, helping with infant care, food collection, and dam building.

Most beaver lodges have two rooms, called dens. The first room is used for drying off after using the underwater entrance. The second, drier room is where the beaver family lives and socializes.