What’s the smallest bird in the world? The answer is the hummingbird (蜂鸟). Even the largest one – the giant hummingbird of western South America – is only about 20 cm long. Its body weighs about 20 g, less than that of most sparrows (麻雀). The smallest species (种类) is the bee hummingbird, which is found only in Cuba, and measures slightly more than 5.5 cm long. Weighing about 2 g, this species is the smallest living bird. People often mistake them for bees.