School of Life Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China.
Princeton School of Public and International Affairs, Princeton University, Princeton, NJ 08540, USA.
Proc Biol Sci. 2022 Jul 13;289(1978):20220678. doi: 10.1098/rspb.2022.0678. Epub 2022 Jul 6.
Collisions between fast-moving objects often cause severe damage, but collision avoidance mechanisms of fast-moving animals remain understudied. Particularly, birds can fly fast and often in large groups, raising the question of how individuals avoid in-flight collisions that are potentially lethal. We tested the collision-avoidance hypothesis, which proposes that conspicuously contrasting ventral wings are visual signals that help birds to avoid collisions. We scored the ventral wing contrasts for a global dataset of 1780 bird species. Phylogenetic comparative analyses showed that larger species had more contrasting ventral wings than smaller species, and that in larger species, colonial breeders had more contrasting ventral wings than non-colonial breeders. Evidently, larger species have lower manoeuvrability than smaller species, and colonial-breeding species frequently encounter con- and heterospecifics, increasing their risk of in-flight collisions. Thus, more contrasting ventral wing patterns in these species are a sensory mechanism that facilitates collision avoidance.
快速移动的物体之间的碰撞通常会造成严重的破坏，但对于快速移动的动物的碰撞回避机制的研究还很不足。特别是鸟类可以快速飞行，而且经常成群结队，这就提出了一个问题，即个体如何避免潜在致命的飞行碰撞。我们测试了回避碰撞假说，该假说认为，明显对比的腹侧翅膀是帮助鸟类避免碰撞的视觉信号。我们为 1780 种鸟类的全球数据集记录了腹侧翅膀的对比度。系统发育比较分析表明，较大的物种比较小的物种具有更明显的对比腹侧翅膀，而且在较大的物种中，群居繁殖者比非群居繁殖者具有更明显的对比腹侧翅膀。显然，较大的物种比较小的物种的机动性更低，而群居繁殖的物种经常遇到同种和异种种群，增加了它们在飞行中碰撞的风险。因此，这些物种中更明显的对比腹侧翅膀模式是一种有助于避免碰撞的感觉机制。
