Hummingbird

Hummingbird
A variety of hummingbirds from Ernst Haeckel's 1904 Kunstformen der Natur (Artforms of Nature)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Trochiliformes or Apodiformes
Family:	Trochilidae Vigors, 1825

Hummingbirds are small birds of the family Trochilidae.

They are among the smallest of birds: most species measure 7.5–13 cm (3–5 in). The smallest living bird species is the 2–5 cm bee hummingbird. They can hover in mid-air by rapidly flapping their wings 12–80 times per second (depending on the species). They are also the only group of birds able to fly backwards.^[1] Their rapid wing beats do actually hum. They can fly at speeds over 15 m/s (54 km/h, 34 mi/h).^[2]

1. ↑ Ridgely, Robert S. and Paul G. Greenfield. 2001. The Birds of Ecuador, volume 2, Field Guide, Cornell University Press.
2. ↑ Clark and Dudley 2009. Flight costs of long, sexually selected tails in hummingbirds. Proceedings of the Royal Society of London.