Flight reconstruction of two European enantiornithines (Aves, Pygostylia) and the achievement of bounding flight in Early Cretaceous birds

Intermittent flight through flap‐gliding (alternating flapping phases and gliding phases with spread wings) or bounding (flapping and ballistic phases with wings folded against the body) are strategies to optimize aerial efficiency which are commonly used among small birds today. The broad morphological disparity of Mesozoic birds suggests that a range of aerial strategies could have evolved early in avian evolution. Based on biomechanics and...