Hummingbirds Have the Fastest Heartbeat
A hummingbird's heart can beat more than 1,200 times per minute while the bird is flying. This rapid rate supplies enough oxygen to power wings that flap up to 80 times every second. When resting, the heartbeat slows dramatically to conserve energy.
💡 Fun detail:
Hummingbirds must eat roughly twice their body weight in nectar each day to fuel their metabolism.
Source: Cornell Lab of Ornithology