Other than insects, while they are in flight hummingbirds have the highest metabolism of all animals. They must consume their bodyweight in nectar each day to survive. Their hearts are capable of reaching at an astonishing 1,260 beats per MINUTE.
In order to survive the night hummingbirds must enter into a hibernation like state called torpor, when the metabolism is significantly reduced. Their heart rate slows and their body temperature goes from 104 F to a mere 54 F.
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