网站首页 | 关于我们 | 广告合作 | 设为首页 | 收藏本站 热点资讯:双语:小米与微软合作 预装微软 美国新任驻华大使博卡斯北京举行
热搜: 英语作文  英语话剧  影视
当前位置: 首页 > 英语考试 > 托福考试 >

托福听力练习之spiders

2012-06-17 12:27[托福考试] 来源: 浏览: 次 评论:0条


Vocabulary

arachnid: n. 蜘蛛类动物(包括蜘珠、蝎子、虱子等)
spider: n. 蜘蛛
species: n. 种类
consume: v. 吃
clutch: n. 一次产的或孵的蛋
eucalyptus: n. 桉树
catch: n. 捕获物
fatten: v. 养肥,使肥胖
nutrient: n. 营养物
unfertilized: adj. 未受精的
bloodstream: n. 血流
joint: n. 接合处
nourishment: n. 食物,营养品
cannibalism: n. 嗜食同类,自相残杀

【听力原文】

Before moving on to a new topic, I want to finish up our unit on arachnids by looking at what may seem a very unusual aspect of spider behavior—a species where the young spiders actually consume the body of their mother.

Unlike most other spiders, this species lays one, and only one, clutch of 40 eggs in her lifetime. The young spiders hatch in mid-spring or early summer,inside a nest of eucalyptus leaves. Their mother spends the warm summer months bringing home large insects, often 10 times her weight, for meal. The catch is always significantly more than her young spiders can eat. So, the mother fattens herself up on this extra prey and stores the nutrients in her extra unfertilized eggs. As the weather turns colder, there are fewer insect prey tohunt. That\'s when the nutrients stored in those extra eggs begin to seep into the mother\'s bloodstream. So, when there are no more insects to feed to the young spiders, they attach themselves to the mother\'s leg joints and draw nourishment by sucking the nutrient-rich blood.

After several weeks, the mother is depleted of all nutrients and she dies. But then how do the young get nourishment? They start to feed on one another. Now,if you recall our discussion of Darwin, you\'ll see the evolutionary value of this: Only the strongest spiders of the clutch will survive this"cannibalism," and the mother spider will have ensured that her genes have an increased chance of survival through future generations.

【看这里~】

如果大家有兴趣的话,请关注【 英语巴士网-托福考试 】栏目,英语巴士网整合了您可能感兴趣的相关英语学习资料,可以多看一下哦(^_^)

英语巴士公众号

欢迎扫描二维码关注英语巴士公众号!

(编辑:admin)

网友评论

网友评论仅供其表达个人看法,并不代表英语巴士网立场。

热门标签