Swift
Nearly 20, see text.
The swifts are a family, Apodidae, of highly aerial birds. They are superficially similar to swallows, but are actually not closely related to passerine species at all; swifts are in the separate order Apodiformes, which they share with hummingbirds. The treeswifts are closely related to the true swifts, but form a separate family, the Hemiprocnidae.
The resemblances between swifts and swallows are due to convergent evolution, reflecting similar life styles based on catching insects in flight.
The family scientific name comes from the Ancient Greek απους, apous, meaning "without feet", since swifts have very short legs and never settle voluntarily on the ground, clinging instead to vertical surfaces. The tradition of depicting swifts without feet continued into the Middle Ages, as seen in the heraldic martlet.
Read more about Swift: Description, Systematics and Evolution
Famous quotes containing the word swift:
“And, is not Virtue in Mankind
The Nutriment that feeds the Mind?”
—Jonathan Swift (1667–1745)
“The broken ridge of the hills
was the line of a lover’s shoulder,
his arm-turn, the path to the hills,
the sudden leap and swift thunder
of mountain boulders, his laugh.”
—Hilda Doolittle (1886–1961)
“Come, agree, the law’s costly.”
—Jonathan Swift (1667–1745)