In various group‐living species, from time to time one of the group members acts as a sentinel and utters alarm calls when detecting a predator. Hearing these calls, other group mates usually react by quickly changing their behaviour. Uttering alarm calls is an anti‐predator mechanism with several possible functions. In this study our aim was to assess the function of alarm calls in the Arabian babbler Argya squamiceps, a cooperatively breeding songbird. We observed 10 groups in natural conditions and recorded 1000 reactions of 55 foraging group members to 268 sets of alarm calls uttered by the sentinels. The most frequent reaction of the group members to the sentinel's alarm calls was to stop foraging immediately, to fly up to the closest treetop and to start calling alarm calls. In all the recorded cases, the sentinel remained in place and continued to call. The alarm calls continued as long as the raptor could be seen, and then ceased gradually, after which babblers flew down and returned to foraging. We conclude that the main function of alarm calls in the Arabian babbler is pursuit deterrence. In particular, while foragers benefit from the information content of the sentinel's alarm calls and react on their basis, the raptor is the primary audience addressed by the calls uttered by the sentinel and the foragers who join it.

中文翻译：

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阿拉伯alarm叫器中的定点警报功能

在各种生活在物种中的物种中，其中一个群体成员有时会充当哨兵，并在检测到掠食者时发出警报。听到这些声音，其他队友通常会通过快速改变其行为做出反应。阻止警报呼叫是一种反掠食性机制，具有多种可能的功能。在这项研究中，我们的目的是评估阿拉伯说话人Argya squamiceps中的警报功能，一种合作繁殖的鸣禽。我们在自然条件下观察了10个小组，并记录了55个觅食小组成员对前哨发出的268组警报呼叫的1000次反应。小组成员对哨兵的警报呼叫最频繁的反应是立即停止觅食，飞到最近的树梢并开始呼叫警报呼叫。在所有记录的案件中，哨兵都留在原地并继续打电话。只要能看到猛禽，警报器就会继续鸣叫，然后逐渐停止，随后ba叫者飞下来并返回觅食。我们得出结论，阿拉伯the叫器中警报呼叫的主要功能是追求威慑力。特别是，虽然觅食者从前哨警报呼叫的信息内容中受益并做出相应反应，