Neither. Reindeer live in the tundra primarily not in deserts.
run around to stay warm.
deers + cold
The legend says he lives in the north and reindeer are the only animals that can serve the purpose that far north. It would get too cold for horses but reindeer are made for cold weather. Also, they can be tamed.
Reindeer have two layers, one thick one, one thin one, they prefer cold areas like Greenland and St. Matthew's Island. A suitable environment for reindeer is a cold climate with constant winds.
Reindeer are mammals. Mammals are homeostatic animals which maintain a warm body temperature.
The reindeer has a coat with two layers, a dense undercoat to provide warmth in the cold weather and a longhaired overcoat that is weather-resistent.
A large reindeer particular to North America.
Reindeer probably cannot survive in warm climates because all there food sources only grow in cold climates. Also, each individual hair on a reindeer's back are hollow and trap air to keep them cool. If the hair traps hot air, the reindeer will overheat. But there's always the possibility that the reindeer will adapt to the warmer climates and change there diet :D
pretty much anything that's body temperature and a bit moist will steam if exposed to cold.
Like all deer, reindeer(or caribou) grow a longer pelt in winter. Being from a bitter cold climate, their coat is longer than white tail or mule deer.
There are no reindeer in Antarctica. No animal lives on the continent: it's too cold and there is no food chain.