小站备考
托福
托福听力
Official20听力真题

托福official20听力lecture4 Snowshoe Hare原文解析+翻译音频

展开
Tip:单击查看句义;划选/双击查生词

[00:00.00]Narrator: Listen to part of a lecture in a biology class.
[00:05.57]Female Professor: Now James, you said you've been to the state of Maine, right?[00:09.98]Male Student: Yeah, actually, I lived in western Maine till I was about 16.[00:13.82]Female Professor: Great. So why don't you tell everybody what it's like there in the winter.[00:18.16]Male Student:  In the winter? Well, it's cold … [00:21.37]and there's lots of snow. You wouldn't believe how much snow we used to get.
[00:25.34]Female Professor: Actually, I would. [00:26.85]I did field research up there a couple of winters, [00:29.41]and it really is an incredible environment. [00:32.18]And to survive in that sort of environment, animals have to adapt … to evolve in response to their surroundings.
[00:39.86]As you'll recall, an adaptation is any feature—uh, physical or behavioral feature—of a species that helps it survive and reproduce. [00:50.36]And in adapting to extreme climates—like Maine in the wintertime—animals can evolve in pretty interesting ways.[00:58.04]Take, for example, the snowshoe hare.
[01:01.41]OK, the snowshoe hare—and of course that’s “H-A-R-E,” like a rabbit … [01:08.47]though I probably should mention that technically a hare is not exactly the same as a rabbit, even though it is very similar. [01:16.83]The primary difference is that a rabbit’s young are born blind and without fur, while a hare’s babies are born with a full coat and able to see.[01:26.83] Now, this snowshoe hare … tell me … what sort of adaptations do you think it's developed that help it survive the Maine winters? [01:36.96]I’ll give you a hint. [01:38.40]Food isn't an issue. [01:40.65]The hare actually has abundant food in the small twigs it finds.[01:44.52]Male Student: Well, I don't know. [01:45.95]I mean, I know we used to try to look for those rabbits, … uh hares, when we went hiking in the winter, but it was often hard to find them in the snow.[01:54.05]Female Professor: Yes, that's exactly right. [01:56.30]The major concern of the snowshoe hare in the winter is predators, [02:00.61]and now that includes humans. [02:02.96]So one of its adaptations is basically camouflage. [02:06.93]In other words, its coat—its fur—turns from brown in the summer to white in the winter, which makes it harder for the hare’s predators to see it against the white snow.
[02:18.53]Male Student: Yeah, but I could swear I remember seeing rabbits in the snow a couple of times … I mean hares … that were brown.
[02:25.04]Female Professor: Well, you may very well have. [02:27.07]Timing is really important, but the snowshoe hare doesn’t always get it exactly right. [02:32.71]Its chances for survival are best if it turns white about the time of the first snowfall. [02:37.81]And, it’s the amount of daylight that triggers the changing of the hare’s coat. [02:42.66]As the days get shorter—that is, as the Sun is up for a shorter and shorter time each day—the snowshoe hare starts growing white fur and shedding its brown fur.
[02:53.27]The hare does a pretty good job with its timing, but sometimes—when there’s a really early or late snow—it stands out. [03:01.86]Plus, it takes about a month for the snowshoe hare's coat to completely change color, [03:07.04]so if there's a particularly early snowfall, it's very likely that the hare’s fur would not yet be totally white. [03:13.75]And that would make this a particularly dangerous time for the hare. [03:17.85] OK, what else? Other adaptations? Susan?
[03:23.34]Female Student: Well, it’s called a hare. So are its feet somehow protected from the cold?[03:29.87]Female Professor: Well, this animal's name does have to do with an adaptation of its feet, [03:34.67]though not like it has warm furry boots or something, to keep its feet from getting cold. [03:40.11]You’ve probably never needed to wear snowshoes, [03:43.41]but … well, snowshoes are not like thick furry shoes designed to keep the feet warm. They’re actually quite thin, but very wide.
[03:52.75]What they do is spread out the weight of the foot coming down on the snow. [03:57.13]See, the problem with walking on snow is that you sink in with every step. [04:01.83]But with snowshoes, you don't sink in, you walk on top of the snow. [04:06.49]It makes walking through the Maine countryside in the winter much easier.[04:10.40]Anyway, the snowshoe hare has an adaptation that plays on this same idea—[04:15.43]it has hind feet that act like snowshoes. [04:18.59]I mean, its paws are wide, and they allow the hare to hop and run just at the surface of deep snow. [04:25.01]And this is a huge advantage for the snowshoe hare, since, by contrast, the feet of its predators usually sink right down into the snow.[04:33.78]Now, another advantage related to this is that, unlike many animals in winter, snowshoe hares can stay lean and lightweight—[04:43.66]they accumulate essentially no body fat. [04:46.69]Can anyone guess why this is so?[04:48.92]Female Student: They don't eat very much?[04:50.48]Female Professor: Well, yes. But not because there isn't enough food around. [04:54.37]It's because, like I said, food is almost always within reach and they don't have to store up a lot of food energy for the harsh winters.

1.What is the lecture mainly about?

你的答案:
正确答案:C
题目解析:
 后才能查看题目解析,还没有账号? 马上注册
And in adapting to extreme climates, like Maine in the winter time, animals can evolve in pretty interesting ways. Take, for example, the snowshoe hare. 通全篇能看出本文主要讲述一种动物,通过特性适应恶劣环境。

学习页面

Medi

terr

anean

加强 + 政府 + 名词后缀

加强的政府——管理

原文例句

加入生词

本文生词 0

色块区域是你收藏过的生词;

查询次数越多,颜色越深哦~

显示文中生词

登录后才能收藏生词哦,现在登录注册>

本文重点词 45

文中加粗单词为本文重点词;

根据词频与核心词范围精心挑选,托福考试必掌握词汇。

显示文中重点词
学习本文词汇

文中划选/双击的生词、加粗重点词已收纳至词盒

可随时点击词盒查看哦~

只有在词句精学模式下才能开启词盒功能哦~

我知道了

词盒
收藏
笔记
我的笔记
5000
保存
反馈