Clark wrote that maximising speed is an important component of the courtship display of Anna's hummingbirds, because of the loud sound generated as they dive. 克拉克认为，对于安娜蜂鸟来说，获取最大速度是其求爱演出里的一个重要剧目，因为当它们俯冲时，能随之生成巨大的啸声。
In previous research, Clark showed that male Anna's hummingbirds spread their outer tail feathers during dives and these vibrate like the reed in a clarinet. 在先前的研究里，克拉克指出雄安娜蜂鸟在俯冲时展开自己的外层尾羽，使之象笛子里的簧片一样随着气流震动。
