Where do swallows hibernate and where do butterflies appear from in spring? The mystery of where some animals disappear to each year puzzled early naturalists. Show more
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Where do swallows hibernate and where do butterflies appear from in spring? The mystery of where some animals disappear to each year puzzled early naturalists. Show more
BBC Two is a lively channel of depth and substance, carrying a range of knowledge-building programming complemented by great drama, comedy and arts.
