• The caribou is the only deer in which females also have antlers.
• Caribou eat shed and other deer antlers to compensate for a lack of lichen in their bodies, especially young caribou often chew the antlers of adults.
• The animals can see in ultraviolet light, which helps them find lichens in winter.

The species has soft, thick brown fur that protects young caribou from the cold, and their wide hooves aid in preventing them from sinking into snow. Adult caribous possess a dense two-layered coat; it is light and very warm in winter, and shorter and darker in summer, protecting them from frost and insects. The adults have large, branched antlers which are used for fighting other males and defense, and these antlers are shed annually and regrown. They also have wide and strong hooves that allow them to walk on deep snow, dig for lichens, and swim effectively. Furthermore, the species has a large nose lined with thick fur, which warms the cold air before it reaches the lungs.