With their bright plumage and eye-catching mode of flight, hummingbirds are some of the most enchanting bird in existence. Yet a hummingbird's life is precarious: their fast-moving wings and faster metabolisms burn through calories at a ferocious rate. If a hummingbird went as little as an hour without drinking nectar, it would starve to death. To survive during their sleep, they enter a state of torpor, with heartbeat and body temperature turned way down to diminish the need for food.

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