Hummingbird
Hummingbirds are birds native to the Americas and constitute the biological family Trochilidae. They are among the smallest of birds, most species measuring in length. Indeed, the smallest extant bird species is a hummingbird, the bee hummingbird weighing less than .
Smallest organisms
The Etruscan shrew ("Suncus etruscus"), is the smallest mammal by mass, weighing only about on average. The bumblebee bat has a smaller skull size. The smallest mammal that ever lived, the shrew-like "Batodonoides vanhouteni", weighed only .