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.

一只现一只老鹰时出低沉的咕哝声，记录其他抬头仰望天空的声音。在注意到蟒蛇时出高音调的叫声，记录了它们扫描地面的情况。