hummingbird
The smallest bird in the world is a hummingbird. Its largest species lives in the Ang mountains of South America and its size reaches only 22 cm.
The smallest representative lives in the islands of Cuba, and has a length of 6 cm from the tip of the beak to the tip of the tail. Even if it is, such a length is recorded due to its beak and tail. Imagine the weight is 2 grams. There is no other dwarf bird on earth.