托福听力TPO1原文 Lecture 4(2)

托福听力TPO1原文 Lecture 4

go their separate ways. Then about six to eight weeks after birth, the offspring leave their mothers.

StudentReally? Just six weeks? Is that possible for the offspring to make it on their own so young?

ProfessorWell, it’s not as if they aren’t ready for the real world because they are. Remember, they mature quickly and the weather’s nice. Also they live in open fields where there is lots of edible vegetation. So roughly six weeks after birth, Eastern marmots are just old enough to take their chances of surviving in the temperate environment. So how does this relate to their behavior?

StudentOh, I get it. Since the climate’s not too bad, the Eastern marmots don't have to rely on each other too much and they really don't need to stay together as a family to survive either.

ProfessorUh-ha. Any contrast, the Olympic marmots? What about them?

StudentWell, they live together as a family and take care of their young until they are at least two years old. They’re really friendly with each other. And what I really like is that they even have greeting ceremonies. And they are not at all aggressive and territorial like the Eastern marmots. So their social behavior is so different from Eastern marmots because of the climate where they live? That seems so bizarre.

ProfessorWell, the Olympic marmots inhabit meadows high in the Olympic Mountains where the weather conditions are much harsher. So there is a lot more wind and snow. The growing season only lasts about two to three months. So in that much shorter period of time, all the Olympic marmots, male and female, eat, play, work and nurture the young together. Because the climate is so harsh, cooperation increases the survival rate of the Olympic marmots. They keep their young at home until they are physically able to survive on their own. This could explain why the social behavior of the Olympic marmots is so unlike that of the Eastern marmots.

翻译独白：听一段生物课的讲座教授：在开始今天的讨论前，我们先回顾一下关于一些动物的行为是如何适应他们环境的案例研究。现在大家来了解一下这两类动物：东部的和奥林匹克山的土拔鼠。土拔鼠属于啮齿动物。它们是大型的地松鼠，体形有一般家猫那样大。它们栖息在不同的地方。即便是这样，据案例研究的材料显示它们也花相当多的时间冬眠，土拔鼠仍然被视为动物行为研究的绝佳对象。为什么会这样呢？

学生：是这样的，在非冬眠时期，你会在空旷地区看到它们。它们白天很活跃，这