Not only does the male Bird of Paradise have fantastic colorful plumage, he dances, poses and completely changes his shape to woo the less exotic-looking females.

雄性天堂鸟不但拥有奇妙多彩的羽毛，它们还会通过舞蹈，摆造型甚至完全改变自己的外形来博取雌性(雌性天堂鸟往往不那么漂亮)的欢心。

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However, plumage, size and shape were primarily used to identify species until the late 1970s when vocalizations were added.

NPR: Brown-And-White Whistling Owl ID'd As New Species