As feathers became larger over time, flapping flight evolved and birds finally became fully air-borne.

随着时间的推移，羽毛变得越来越大，扑翼飞行逐渐发展，鸟类最终完全可以在空中飞行。

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As we've discussed, birds are apparently descendants of dinosaurs and shared many commonalities with some dinosaur species, like feathers and maybe even flight and of course egg laid.

正如我们讨论过的，鸟类显然是恐龙的后代，与一些恐龙物种有许多共同之处，比如羽毛，甚至飞行，当然还有产卵。

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And of course they aid flight-but not always, as ostriches and penguins, which have feathers but do not fly, demonstrate.

当然，羽毛还能辅助飞行——但这也并非绝对，鸵鸟和企鹅虽然也拥有羽毛，但却不会飞行。

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Found only in these woods, the large bird is a beautiful sight, with its distinctive green and blue colouration, crested head feathers and, when in flight, the red flash of its wings.

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But Dr Dial wanted to be sure, so he compared the accomplishments of normal partridges with birds that had their wing feathers clipped to half their normal surface area, and to even less fortunate fowl whose main flight feathers were entirely plucked.

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