乌鸦有个习性:将吃剩下的食物藏起来,以备以后享用。奇怪的是,它们不仅藏食物,还藏其他不能食用的物品。一天,两个女性研究人员将一个小塑料玩具放在了离乌鸦不远的地方,然后远远地躲起来,观察乌鸦的动静。很快,乌鸦来到玩具跟前,先是用喙玩弄,然后叼起 The raven has a habit of hiding the rest of the food for later use. Curiously, they hide not only food but also other inanimate items. One day, two female researchers put a small plastic toy a short distance away from the raven and then farther away to observe the movement of the raven. Soon, the crow came to the toy, first with the beak playing, and then picked up