評論
打印
Now listen to part of a lecture in a biology class.
請聽生物課上的部分內容。
OK, so let's talk about what happened to a certain type of insect, a moth, a red-and-black moth that lives in Europe.
好了，我們來講講某種昆蟲的遭遇，這是一種蛾子，一種生活在歐洲的紅黑色飛蛾。
These moths eat a plant called Ragwort and they live in fields where the Ragwort plants grow.
這種蛾子以狗舌草為食，生活在狗舌草生長的田野里。
Now, there was a group of moth that lived in one of these fields and, for many years, there was a lot of Ragwort growing there.
現在，有一群飛蛾就生活在其中一片這樣的田野里，多年以來，那里的狗舌草都生長得十分旺盛。
So the moth had plenty to eat and the total number of moth in the field stayed pretty much the same.
所以飛蛾有大量的食物可以食用，那片田野里的飛蛾總數也基本保持不變。
But then one year it rained a lot less than usual and the Ragwort didn't grow as well.
然而，有一年降雨較之往年少了許多，狗舌草的長勢也不好。
The result was that the moth didn't get enough to eat and many didn't survive but even the ones that did survive didn't lay as many eggs as before.
結果導致飛蛾食物不足，許多蛾子無法存活，即使有些飛蛾得以幸存，它們所產的卵也不如往年多。
So that year the moth population in the field was quite a bit smaller.
所以那一年那片田野的飛蛾總數減少了許多。
The next year, though, the amount of rainfall returned to normal again, many more Ragwort plants grew and, once again, there was a lot available for the moth to eat.
不過，下一年降雨量還是恢復到了正常水平，狗舌草也長勢喜人，飛蛾也再次有了足夠的食物。
So that year the moth population increased and the female moth laid many more eggs than the year before.
于是那一年飛蛾總數有所增加，母蛾產卵量也比前一年多了許多。
And now, after all that rainfall and plant growth, there were just as many moth in the Ragwort field as there were before.
現在，多虧了這些降雨和茂盛的狗舌草，那片狗舌草地里的飛蛾數量恢復到了從前的水平。
