Recordings of the low grunts of a vervet who spotted an eagle led other vervets to look up into the sky; recordings of the high-pitched chutters emitted by a vervet upon noticing a python caused them to scan the ground.

一只长尾发现一只老鹰时发出低哝声，记录其他长尾抬头仰望天空声音。长尾在注意到蟒蛇时发出高音调叫声，记录了它们扫描地面情况。