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.

一长尾黑颚猴发现一时发出低沉咕哝声，记录其他长尾黑颚猴抬头仰望声音。长尾黑颚猴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。