Members of this school think that powered flight developed as a natural extension of gliding (such controlled falling is used as a way of travelling from tree to tree by several arboreal species today).

• 这个学派的成员认为，这让鸟的滑行能力自然而然地进化到飞行能力（今天的一些树栖物种从一棵树到达另一颗树就使用了这种能自控的下滑能力）。