Predictions of flight styles for fossil birds in different plots.

fprim, average primary feather length; ta, average total arm length (humerus+ulna+hand); PCA, principal component analysis; DFA, discriminant function analysis; CF, ‘continuous flapping’; FS, ‘flapping and soaring’; FG, ‘flapping and gliding’; PT, ‘passerine-type flight’.

fprim：初级飞羽平均长度；ta：翼总长度均值（肱骨+尺骨+翼手部）；PCA：主成分分析（principal component analysis）；DFA：判别函数分析（discriminant function analysis）；CF：持续振翅（continuous flapping）；FS：振翅与翱翔（flapping and soaring）；FG：振翅与滑翔（flapping and gliding）；PT：雀型飞行（passerine-type flight）。