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Birds are one of only four taxonomic groups to have evolved powered flight. A number of animals are capable of aerial locomotion, either by powered flight or by gliding. This trait has appeared by evolution many times, without any single common ancestor. Flight has evolved at least four times in separate animals: insects, pterosaurs, birds, and ...
Bird flight is the primary mode of locomotion used by most bird species in which birds take off and fly. Flight assists birds with feeding, breeding , avoiding predators , and migrating . Bird flight includes multiple types of motion, including hovering, taking off, and landing, involving many complex movements.
The WAIR hypothesis, a version of the "cursorial model" of the evolution of avian flight, in which birds' wings originated from forelimb modifications that provided downforce, enabling the proto-birds to run up extremely steep slopes such as the trunks of trees, was prompted by observation of young chukar chicks, and proposes that wings ...
Two clades of avemetatarsalians, pterosaurs and birds, independently evolved flight. Pterosaurs are the earliest vertebrates known to have evolved powered flight. Their wings are formed by a membrane of skin, muscle, and other tissues stretching from the ankles to a dramatically lengthened fourth finger. [9] Birds evolved flight much later.
The Cretaceous saw the rise of more modern birds with a more rigid ribcage with a carina and shoulders able to allow for a powerful upstroke, essential to sustained powered flight [citation needed]. Another improvement was the appearance of an alula , used to achieve better control of landing or flight at low speeds [ citation needed ] .
To achieve powered flight, forward flight birds must counteract drag forces that act opposite the direction of flight. Drag forces acting on a flying animal are composed of parasitic drag on the body fuselage and induced drag on the wings, both acting against the relative direction of flight.
An American Airlines flight departing New York's LaGuardia Airport on Thursday evening had to divert to nearby John F. Kennedy International shortly after takeoff after a reported bird strike ...
The only groups of living things that use powered flight are birds, insects, and bats, while many groups have evolved gliding. The extinct pterosaurs , an order of reptiles contemporaneous with the dinosaurs , were also very successful flying animals, [ 3 ] and there were apparently some flying dinosaurs (see Flying and gliding animals#Non ...