搜索关注在线英语听力室公众号:tingroom,领取免费英语资料大礼包。
(单词翻译)
Invasive species can decrease biodiversity and drive resident species to the brink1 of extinction2. But how do these interlopers fare so well in unfamiliar3 territory? One idea is that they’ve escaped their enemies, for example, the parasites5 that keep them in check on their home turf. But a study in the journal Biology Letters suggests that notion doesn’t always stand up. Because at least one kind of invasive shrimp6 is an even bigger pest when it has a parasite4 on board.
The scientists were studying a freshwater shrimp commonly found in England. Fishermen brought the shrimp to Northern Ireland in the 1950s as a tasty treat for local trout7. Well, the shrimp liked the new digs. So much that they’ve all but eliminated the native shrimp species. The strange thing is, they may have parasites to thank.
In some streams, 70 percent of the invaders8 are infected with an intestinal9 worm that doesn’t go for the native shrimp. But this gut10 worm doesn’t slow them down. In fact, infected shrimp eat 30 percent more prey11 than those that are parasite-free.
Which perhaps is not surprising. If you had a worm that constituted a quarter of your body weight, you’d eat more too.
Thanks for the minute for Scientific American's 60-Second Science. I'm Karen Hopkin.
1 brink | |
n.(悬崖、河流等的)边缘,边沿 | |
参考例句: |
|
|
2 extinction | |
n.熄灭,消亡,消灭,灭绝,绝种 | |
参考例句: |
|
|
3 unfamiliar | |
adj.陌生的,不熟悉的 | |
参考例句: |
|
|
4 parasite | |
n.寄生虫;寄生菌;食客 | |
参考例句: |
|
|
5 parasites | |
寄生物( parasite的名词复数 ); 靠他人为生的人; 诸虫 | |
参考例句: |
|
|
6 shrimp | |
n.虾,小虾;矮小的人 | |
参考例句: |
|
|
7 trout | |
n.鳟鱼;鲑鱼(属) | |
参考例句: |
|
|
8 invaders | |
入侵者,侵略者,侵入物( invader的名词复数 ) | |
参考例句: |
|
|
9 intestinal | |
adj.肠的;肠壁;肠道细菌 | |
参考例句: |
|
|
10 gut | |
n.[pl.]胆量;内脏;adj.本能的;vt.取出内脏 | |
参考例句: |
|
|
11 prey | |
n.被掠食者,牺牲者,掠食;v.捕食,掠夺,折磨 | |
参考例句: |
|
|
本文本内容来源于互联网抓取和网友提交,仅供参考,部分栏目没有内容,如果您有更合适的内容,欢迎 点击提交 分享给大家。