『新东方在线托福口语』为托福考生准备了ETS托福TPO/Official 33 Task 3口语练习：Carrying Capacity &nbsp;
An animal species needs to h原文题目答案解析，TPO/Official 33 Task 3口语原文范文音频翻译。

托福TPO/Official 33 Task 3口语原文独立/综合口语题目答案解析-范文音频翻译-新东方托福官方网校手机版

现在听一下生物课上的一节课。

Narrator: Now listen to part of a lecture in a Biology class.

教授：好的，让我们来谈谈在某种类型昆虫身上发生了什么，

Professor: Okay, so let's talk about what happened to a certain type of insect,

就来说一种蛾子，一种生活在欧洲的红黑蛾。

a moth, a red and black moth that lives in Europe.

这些蛾子吃一种叫千里光的植物，

它们生活在千里光生长的地方。

and they live in fields where the Ragwort plants grow.

有一群蛾子曾经生活在这些田野里，

Now there was a group of moth that lived in one of these fields,

很多年来，那里都有很多的千里光生长。

and for many years there was a lot of Ragwort growing there.

这个区域的蛾子总数基本保持不变。

and the total number of moths in the field stayed pretty much the same.

但有一年，雨下得比平时少了很多，而千里光的生长也没有那么好。

But then one year it rained a lot less than usual and the Ragwort didn't grow as well.

结果是，这些蛾子没有得到足够的食物，很多没有活下来。

The result was that the moths didn't get enough to eat and many didn't survive.

即使是那些幸存下来的蛾子也没有像以前那样产下那么多的卵。

But even the ones that did survive didn't lay as many eggs as before.

所以那一年，这个区域的蛾子数量要小得多。

So that year, the moth population in the field was quite a bit smaller.

the amount of rainfall returned to normal again.

更多的千里光生长，有很多可供蛾子吃的东西。

Many more Ragwort plants grew and once again there was a lot available for the moths to eat.

So that year the moth population increased,

and the female moths laid many more eggs than the year before.

在经历了所有的降雨和植物的生长之后，

And now, after all that rainfall and plant growth,

就像以前一样，在千里光草场里有同样多的蛾子。

there were just as many moths in the Ragwort field as there were before.

Carrying Capacity &nbsp;
An animal species needs to have enough resources, like food and water, to survive in any given environment. However, because resources are limited, only a certain number of animals of a particular species are able to survive in a given habitat. The greatest number a habitat can support is known as the carrying capacity. If nothing happens to disrupt or unbalance the relationship between the animal and its habitat, the carrying capacity will remain stable. However, a carrying capacity is not fixed. If there is a significant disruption, such as an environmental event that alters the amount of available resources in the habitat, the carrying capacity will change.
 
<img src="/upload/ti/2427000-2428000/2427241/65098017d50242d5bcd16f15da376567.jpg">
Explain the concept of carrying capacity using the example of the moth and Ragwort.