What is the diet of a captive reindeer?
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
Reindeer is both the singular and plural. This is because of the English language's Germanic origin. Germanic languages have neuter nouns where the singular and plural are exactly the same. To give a Germanic to English example:: ett hjort = one deer tre hjort = three deer The modern English language has retained some of its Germanic features like this, especially when it comes to animals (sheep, fish, deer, etc).
For about the first 45 days of life, the caribou babies only drink their mother's milk, as do all mammals. After this time, they will beign to adopt the adults' diet: lichens (especially reindeer moss), leaves, sedges, and grasses. They will continue to suckle alongside the adult diet until the fall (they are born in late spring). Then, they eat only the adults' diet.