Reindeer, also known as caribou, are the largest species of deer. Males can weigh up to 400 pounds, while females weigh up to 200 pounds. Their antlers can grow up to five feet wide and are shed each year. Reindeer also have a distinctive coat that changes colors seasonally. During the summer, their coats are brown or reddish-brown, while in the winter, they turn white for camouflage against the snow. Reindeer are also known for their ability to travel long distances without rest and can run up to 50 miles per hour.