Hibernation in animals is an extremely fascinating phenomenon, one that biologists are not yet close to understanding fully. However, it is quite easy to understand why animals hibernate during the cold winter months. Usually, it is because their food is scarce during this time. Animals that are herbivores will find the winters extremely tough, because all of the vegetation will have died off by the time winter arrives. Hibernation is essentially a way of dealing with this food shortage. Animals like birds rely on seeds and small insects for sustenance. Obviously, these will also be quite scarce in the winter when the ground becomes covered and frozen. Many birds address their upcoming food shortage in a different way: they migrate to warmer areas where their sources of food will be plentiful.The main reason animals hibernate is

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