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飞翔是鳥类生活中极重要的一种运动方式。除去属于古顎总目(Palaeognathae)为数不多的平胸鳥类外,所有屬于今顎总目(Neognathae)的突胸鳥类,极大多数都能飞翔。通常我們注意到的只是鳥类鼓动兩翼的飞翔。这是一种最普通也是最基本的飞行方式。另一种飞行方式是滑翔。在高空滑翔,常又称之为翱翔。鳥于滑翔时,用不着鼓动兩翼而却能作長时間的飞行。把身体維持在空气中不致墮落,或是于降落时,逐漸失去高度,緩緩着陆。这时,它的动能来源是鳥体以外的气流的动能。
Flying is a very important form of movement in bird life. Except for the small number of flat-breasted birds belonging to the Palaeognathae (Palaeognathae), most of the thigh-breasted birds belonging to Neognathae can fly. What we usually notice is only the flight of the wings of the birds. This is the most common and basic flight mode. Another way to fly is gliding. Glide in the sky, often referred to as soaring. When a bird is gliding, it can fly for a long time without needing to instigate the wings. Keeping the body in the air does not cause it to fall, or it gradually loses its height and lands slowly when it lands. At this time, its kinetic energy source is the kinetic energy of the airflow outside the bird body.