Antlers are the reindeer’s most memorable characteristic. In comparison to body size, reindeer have the largest and heaviest antlers of all living deer species. A male’s antlers can measure up to 130 centimeters long, and a female’s antlers can reach 50 centimeters.
Reindeer have two coat layers: an undercoat of fine, soft wool that stays right next to their skin, and a top layer of long, hollow guard hairs. The air trapped inside the guard hairs holds in body heat to keep the animal warm against wind and cold. The hollow hairs also help the reindeer float, allowing it to swim across a river, if needed.