『新东方在线托福听力』为托福考生准备了ETS托福TPO/Official 1 Lec 4听力练习：What is the main topic of the lecture?原文题目答案解析，TPO/Official 1 Lec 4听力原文范文音频翻译。

托福TPO/Official 1 Lec 4听力原文What is the main topic of the lecture?-新东方托福官方网校手机版

Narrator: Listen to part of a lecture in a biology class.

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。

Professor: For today's discussion, we'll review the case study on how some animals have behaviorally adapted to their environments.

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。

Now you had to read about two animal species, the Eastern marmot and the Olympic marmot.

它们是大型的地松鼠，体形有一般家猫那样大。

They are large ground squirrels, about the size of an average house cat.

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。

And even though they spend the significant portion of the year hibernating, according to this case study, marmots are still considered excellent subjects for animal behavioral studies.

学生：是这样的，在非冬眠时期，你会在空旷地区看到它们。

Student: Well, when they are not hibernating, you can find them in open areas.

它们白天很活跃，这样发现它们就不是难事了，对吧？

And they are pretty active during the day, which makes them easy to observe, right?

教授：啊哈，我们首先讨论一下东部的土拔鼠。

Professor: Uh-ha, so first let's discuss the Eastern marmots.

它们的住所遍布北美东部地区，这里气候温和，全年有五个月以上的生长期，在这段时间里它们会进行交配，玩耍和觅食。

They reside throughout the eastern region of North America where there is a temperate climate, where the growing season lasts for at least five months of the year, which is when they do all their mating, playing and eating.

一开始仅凭阅读材料我并不知道生长期是什么意思,但我现在知道了。

At first I wasn't sure what growing season meant, just from the reading, but now I get it.

是它们用来生长的一段时间，对吧？

It's the amount of time it takes for them to grow, right?

教授：嗯？哦，不是的，不好意思。

不是跟东部土拔鼠用在生长的时间有关。

It's not about the time it takes for Eastern marmots to grow.

那时，地上没有冰雪覆盖，草木也没有结霜，嗯，土拔鼠喜欢吃的植物嫩芽和花蕾开始生长。

That is when it's not covered in snow and there is no frost covering the grass and, umm, vegetative parts of a plant's herbs and the flowers the marmots like to eat.

所以，生长期指的是它们所吃食物的可获得性，是不是？

So growing season refers to the availability of the food they eat, OK?

那么，你们如何描述东部土拔鼠的社会习性？

So now how would you describe the Eastern marmots' social habits?

学生：它们的区域所属感很强，而且独来独往，同时即便是与同类相处也表现出非常强的侵略性。

Student: Well, they are really territorial, and loners, and just so aggressive even with other Eastern marmots.

And their mating ritual is just so impersonal.

教授：啊哈？春天，当它们从冬眠中醒来出来活动时，交配过程就开始了。

Professor: Uh-ha? Now when they emerge in the spring from hibernation, the mating process begins.

它们聚到一块交配，随后各奔东西。

For them, well, they come together to mate and then they go their separate ways.

产仔后的六到八周，小土拔鼠们离开鼠妈妈。

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

Is that possible for the offspring to make it on their own so young?

教授：并不是因为它们太小而不能适应现实世界。

Professor: Well, it's not as if they aren't ready for the real world because they are.

记住，它们成熟很快，而且天气也不错。

Remember, they mature quickly and the weather's nice.

此外，它们住在盛产可食植被的空旷地区。

Also they live in open fields where there is lots of edible vegetation.

所以，大概出生后六周，东部土拔鼠能长到足以在这温暖的环境中一试身手。

So roughly six weeks after birth, Eastern marmots are just old enough to take their chances of surviving in the temperate environment.

那么，这又跟它们的行为有什么关系呢？

So how does this relate to their behavior?

因为气候还不错，东部土拔鼠没必要过于相互依赖，也没有必要以家庭为单位而存在。

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.

有没有与奥利匹斯山土拔鼠的对比？

学生：它们以家庭为单位过着群居生活，同时照顾幼鼠直到它们长到两岁。

Student: Well, they live together as a family and take care of their young until they are at least two years old.

我很看好的一点是它们见面还有招呼礼节。

And what I really like is that they even have greeting ceremonies.

此外，它们一点都不好斗，地域所属感也不强。

And they are not at all aggressive and territorial like the Eastern marmots.

这两点跟东部土拔鼠是大相径庭的。难道气候造成了它们迥异的社会习性？

So their social behavior is so different from Eastern marmots because of the climate where they live?

教授：事实上，奥林匹斯松土拔鼠栖息的草地在奥林匹克山脉的高地，那里的气候条件要恶劣得多。

Professor: Well, the Olympic marmots inhabit meadows high in the Olympic Mountains where the weather conditions are much harsher.

The growing season only lasts about two to three months.

在那相对短得多的时间里，所有的奥林匹斯松土拔鼠，不分雄雌，觅食，玩耍，劳作和养育幼鼠。

So in that much shorter period of time, all the Olympic marmots, male and female, eat, play, work and nurture the young together.

因为气候恶劣，协作能提高奥林匹斯松土拔鼠的存活率。

Because the climate is so harsh, cooperation increases the survival rate of the Olympic marmots.

它们抚育幼鼠直到幼鼠能自食其力。

They keep their young at home until they are physically able to survive on their own.

这能解释为什么奥林匹斯松土拔鼠的社会习性和东部土拔鼠的（社会习性）如此不同。

This could explain why the social behavior of the Olympic marmots is so unlike that of the Eastern marmots.

According to the case study, why are marmots ideal for observation?

What reason does the professor give for the differences in marmot behaviour patterns?

Narrator Listen to part of a lecture in a biology class. Professor For today’s discussion, we’ll review the case study on how some animals have behaviorally adapted to their environments. Now you had to read about two animal species, the Eastern marmot and the Olympic marmot. Marmots are rodents. They are large ground squirrels, about the size of an average house cat. And they live in a variety of habitats. And even though they spend the significant portion of the year hibernating, according to this case study, marmots are still considered excellent subjects for animal behavioral studies. Why is that? Student Well, when they are not hibernating, you can find them in open areas. And they are pretty active during the day, which makes them easy to observe, right? Professor Uh-huh, so first let’s discuss the Eastern marmots. They reside throughout the eastern region of North America where there is a temperate climate, where the growing season lasts for at least five months of the year, which is when they do all their mating, playing and eating. Student Oh, I see. At first I wasn’t sure what growing season meant, just from the reading. But now I get it. It's the amount of time it takes for them to grow, right? So it would be five months? Professor Umm? Oh, uh… I’m sorry but no. It has nothing to do with that. It's not about the time it takes for Eastern marmots to grow. It’s when the food is available. That is when it’s not covered in snow and there is no frost covering the grass and, umm, vegetative parts of a plant’s herbs and the flowers the marmots like to eat. So growing season refers to the availability of the food they eat, OK? So now how would you describe the Eastern marmots’ social habits? Student Well, they are really territorial, and loners, and just so aggressive even with other Eastern marmots. And their mating ritual is just so impersonal. Professor Uh-huh? Now when they emerge in the spring from hibernation, the mating process begins. For them, well, they come together to mate and then they go their separate ways. Then about six to eight weeks after birth, the offspring leave their mothers. Student Really? Just six weeks? Is that possible for the offspring to make it on their own so young? Professor Well, 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? Student Oh, 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. Professor Uh-ha. Any contrast, the Olympic marmots? What about them? Student Well, 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. Professor Well, 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. Student Oh, I see. At first I wasn’t sure what growing season meant, just from the reading. But now I get it. It's the amount of time it takes for them to grow, right? So it would be five months? Professor Umm? Oh, uh… I’m sorry but no. It has nothing to do with that. It's not about the time it takes for Eastern marmots to grow. It’s when the food is available. That is when it’s not covered in snow and there is no frost covering the grass and, umm, vegetative parts of a plant’s herbs and the flowers the marmots like to eat. So growing season refers to the availability of the food they eat, OK? Student Really? Just six weeks? Is that possible for the offspring to make it on their own so young? Professor Well, 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?