The bear has no idea that its days are numbered unless it remains in the forest and hunts in the traditional way for its meals. But that bear was following the wisdom natural selection had programmed in its genes: food that is high in proteins and sugars is good for you, and the less energy you expend getting it, the better.
一只发现了美味的动物抵制不了再次轻易获得美味的诱惑，我们都会为它感到遗憾。除非待在树林里以传统的方式捕猎食物，否则它的生命就已经进入了倒计时，这一点黑熊并不清楚。可那头黑熊是按照自然选择在它基因中种下的智慧来采取行动：富含蛋白质和糖的食物非常有益，而且获取食物消耗的能量越少越好。