Codex on the Flight of Birds of a kite as seeking a wind current. When the winds are high, one will see the bird very high in the sky, but when the winds are low, the bird stays closer to the ground. Leonardo describes how a bird rests in the air, after flapping its wings to gain altitude, by gliding downward to the ground. Folio 6 contains multiple diagrams of birds flying and their bone structure, and all of the commentary is on flight and how birds fly the way that they do. Leonardo starts off by describing how a bird ascends or descends in different
Collared bush robin a white supercilium. The rufous upper breast, mantle and scapulars form a collar. The back is sooty-black, the wings are black and brownish-black, and the tail is black. The lower breast is buffish-yellow, and the belly varies from grey-white to buffish-olive. The beak and legs are black. The female has a less distinct supercilium. The upperparts are mostly dull olive-brown, and the wings and tail are dark brown. The underparts are variable. The throat and breast are warm brown, but the throat is sometimes blackish, and the breast can be pale yellow or yellowish-olive. The juvenile bird can be distinguished