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第1段
1 .<-NARRATOR:-> Now listen to part of a lecture on this topic in a biology class.
现在请听生物课上关于这个话题的部分内容。
第2段
1 .<-MALE PROFESSOR:-> OK, so we sometimes see this with animals that live in parts of the world where it gets very cold in the winter.
我们有时候会看见生活在冬天十分寒冷的地区的动物采用这种做法。
2 .For example, in the northeastern United States,
比如，在美国东北部，
3 .there's a species of squirrel that does this.
有一种松鼠就是这么做的。
第3段
1 .This squirrel, like many species of squirrel,
和其他种类的松鼠一样，
2 .loves to eat nuts;
这种松鼠也非常喜欢吃坚果。
3 .nuts are one of its primary sources of food.
坚果是它主要的食物来源之一。
4 .Now, nuts are very difficult to find in the winter,
不过，冬天很难找到坚果。
5 .but in the autumn, they're lying all over the place,
但是在秋天的时候，坚果遍地都是，
6 .because that's when they fall from the trees.
因为它们就是这个时节从树上掉下来的。
7 .So what this squirrel does is, in the autumn,
所以，这种松鼠的做法就是：秋天的时候，
8 .it spends a lot of time finding nuts.
它会花大量的时间去寻找坚果。
9 .After it finds a nut, it
找到坚果之后，
10 .prepares it-it takes off the outer shell, and cleans it.
就开始收拾它们，把外壳剥掉并清理干净。
11 .This preparation may in some way help preserve the nut
这种准备工作也许在某种程度上会有利于坚果的保存，
12 .and or may make it easier to eat later on.
或者方便之后食用。
第4段
1 .The squirrel then digs a little hole in the ground
接着松鼠会在地上挖一个小洞，
2 .and buries the nut.
把坚果埋起来。
3 .In one autumn, this squirrel may bury hundreds of nuts.
这种松鼠一个秋天能埋起来数百颗坚果。
4 .But it doesn't just dig a big hole and put all the nuts in it and cover them up.
但它并不是简单地挖一个大洞，把所有的坚果扔进去然后埋起来。
5 .No. It digs hundreds of holes, all over the place, and it puts just one nut in each hole.
它会挖上数百个小洞，到处都是。每个洞它只放一颗坚果。
第5段
1 .Now why would it do that?
那么，它为什么这么做呢？
2 .Well, probably primarily because,
也许主要是因为
3 .even if other animals happen to find some of the holes, some of the nuts,
即使别的动物碰巧发现了其中的一些洞，拿走了洞里的坚果，
4 .the squirrel will still have a lot of other holes with nuts in them,
松鼠仍有很多别的埋着坚果的洞，
5 .so it'll still have enough food to survive the winter.
所以它还是有充足的食物过冬。