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鸟类的飞行活动,是它们适应环境和维持生命的重要手段,飞行功能本身就是进化的结果。鸟类能够飞行,是由于它们有一个特殊构造的身体。从一只鸟的外形来看,它有四个组成飞行能力的部分:翅膀、尾巴、鸟腿和鸟身。翅膀的作用可以生产飞行动力,尾巴的作用可以使鸟儿飞得平稳机动,鸟腿是起飞和着陆的工具,鸟身除了把各个部分连成一个整体外,附在身上的飞行肌肉可以扇动翅膀,产生力量。
The flight of birds is an important means for them to adapt to the environment and maintain their life. Flight function itself is the result of evolution. Birds can fly because they have a specially constructed body. From the appearance of a bird, it has four parts that make up the flying ability: the wings, the tail, the bird’s legs and the bird’s body. The role of wings can produce flying power, the role of the tail can make the birds fly smoothly, the legs are taking off and landing tools, in addition to the bird body to connect the various parts as a whole, attached to the body’s flying muscles can flap wings , Produce strength.