Data from: Ontogeny of aerial righting and wing flapping in juvenile birds

Mechanisms of aerial righting in juvenile chukar partridge (Alectoris chukar) were studied from hatching to 14 days-post-hatching (dph). Asymmetric movements of the wings were used from 1 to 8 dph to effect progressively more successful righting behaviour via body roll. Following 8 dph, wing motions transitioned to bilaterally symmetric flapping that yielded aerial righting via nose-down pitch, along with substantial increases in vertical force production during descent. Ontogenetically, the use of such wing motions to effect aerial righting precedes both symmetric flapping and a previously documented behaviour in chukar (i.e. wing-assisted incline running) hypothesized to be relevant to incipient flight evolution in birds. These findings highlight the importance of asymmetric wing activation and controlled aerial manoeuvres during bird development and are potentially relevant to understanding the origins of avian flight.

本研究针对孵化后至14日龄（days-post-hatching，下文简称dph）的石鸡（Alectoris chukar）幼雏的空中扶正机制展开探究。在孵化后1至8日龄阶段，个体通过翼部不对称运动，经身体翻滚逐步提升空中扶正行为的成功率。孵化8日龄后，翼部运动转变为双侧对称拍动，该运动可通过机头向下的俯仰动作实现空中扶正，同时在下降过程中的垂直力产出显著提升。从个体发育层面来看，利用此类翼部运动实现空中扶正的行为，早于对称拍动以及此前文献中记载的石鸡翼辅助爬坡运动（wing-assisted incline running）——该行为被推测与鸟类初期飞行演化相关。上述研究结果凸显了鸟类发育过程中翼部不对称激活与受控空中机动动作的重要性，且对理解鸟类飞行的起源具有潜在参考价值。