Common swift ( Apus apus )
From wikipedia
The common swift ( Apus apus ) is a medium-sized bird , superficially similar to the barn swallow or house martin but somewhat larger , though not stemming from those passerine species , being in the order Apodiformes . The resemblances between the groups are due to convergent evolution , reflecting similar contextual development . The swifts ' nearest relatives are thought [ by whom ?] to be the New World hummingbirds and the Southeast Asian treeswifts . Its scientific name Apus is Latin for a swift , thought by the ancients to be a type of swallow with no feet ( from Ancient Greek α , a , " without ", and πούς , pous , " foot ").[ 2 ] Swifts have very short legs which they use primarily for clinging to vertical surfaces ( hence the German name Mauersegler , literally meaning " wall-glider "). They never settle voluntarily on the ground , where they would be vulnerable to accidents and predation , and non-breeding individuals may spend up to ten months in continuous flight .[ 3 ]
Taxonomy [ edit ] The common swift was one of the many species described by the Swedish naturalist Carl Linnaeus in 1 758 in the tenth edition of his Systema Naturae . He introduced the binomial name Hirundo apus .[ 4 ] The current genus Apus was erected by the Italian naturalist Giovanni Antonio Scopoliin 1 777 based on tautonymy .[ 5 ][ 6 ] The word apus is the Latin word for a swift . It is derived from the Ancient Greek α , a , " without ", and πούς , pous , " foot ", based on the belief that these birds were a form of swallow that lacked feet .[ 2 ] The predecessor of the Central European subspecies which lived during the last ice age has been described as Apus apus palapus .
Description [ edit ] Common swifts are 1 6 – 1 7 cm ( 6.3 – 6.7 in ) long with a wingspan of 38 – 40 cm ( 1 5 – 1 6 in )[ 7 ] and entirely blackish-brown except for a small white or pale grey patch on their chins which is not visible from a distance . They have a short forked tail and very long swept-back wings that resemble a crescent or a boomerang .