Interesting Facts about Reindeer
Reindeer are thought to be the only mammals that can see ultraviolet light. This helps them see things in bright snowy conditions as the ultraviolet light creates sharp contrast with objects other than snow. Their noses are also specialised and designed for increased internal surface area which allows cold dry air to moisten as they breath in.
There are very few reindeer which are truly wild, some roaming animals are escaped domestic stock, and even the reindeer on the Tundra (just below the North Pole) are owned by Saami herdsmen.