The smallest bird in the world is the bee hummingbird¹ (Mellisuga helenae), native to Cuba. Males measure about 5-6 cm (2-2.4 inches) in length and weigh just 1.6-2 grams (less than a dime). Females are slightly larger. Known for their iridescent² feathers and rapid wing beats (80 times per second), they feed on nectar and insects. Their tiny size and high metabolism³ require them to consume half their body weight daily.

世界上最小的鸟类是吸蜜蜂鸟（Mellisuga helenae），分布于古巴。雄鸟体长仅5-6厘米（2-2.4英寸），体重1.6-2克（比一枚硬币还轻）。雌鸟稍大。它们以花蜜和昆虫为食，羽毛具彩虹光泽，每秒振翅80次。因体型极小且新陈代谢极快，每天需消耗自身体重一半的食物。