英语听力文摘 English Digest 536、缓慢的生存！！
时间：2018-12-31 作者：英语课 分类：英语听力文摘 English Digest
英语课
Silkworms have been bred over thousands of years to behave quite unlike their caterpillar 2 cousins in the wild. That’s because people purposely breed silkworms to fit this job description:
WANTED–Superlative silk producers. Benefits include housing, unlimited 3 food and protection from all predators 4. Wanderlust greatly discouraged. No opportunity for travel.
Obviously, what makes a good silk producer in captivity 5 is very different from what helps a caterpillar survive in the wild. Commercial silkworms are dynamos at silk production, and compared to their wild relatives, rather sluggish about everything else.
Outdoors, you’ve probably seen caterpillars 6 crawling to find food or hide from birds, but commercial silkworm caterpillars hardly move. For silk production, they’re kept on open trays because they’re content to stay put, as long as they have a steady supply of mulberry leaves. Even when they reach the moth 7 stage, commercial silkworms are surprisingly immobile. Wild moths 8 fly to evade 9 predators and to lay their eggs in different areas. However, commercial silkworm moths haven’t needed to do these things for thousands of years. They’ve completely lost the ability to fly, even though they still have wings!
Here’s another difference. In the wild, moths are often very particular about where they’ll lay eggs. This ensures that baby caterpillars can chomp 10 their favorite leaves as soon as they hatch. Commercial silkworm moths have lost that instinct too. They’ll even lay eggs on a sheet of paper, where it’s easy for humans to keep track of them.
adj.懒惰的，迟钝的，无精打采的
- This humid heat makes you feel rather sluggish.这种湿热的天气使人感到懒洋洋的。
- Circulation is much more sluggish in the feet than in the hands.脚部的循环比手部的循环缓慢得多。
n.毛虫，蝴蝶的幼虫
- A butterfly is produced by metamorphosis from a caterpillar.蝴蝶是由毛虫脱胎变成的。
- A caterpillar must pass through the cocoon stage to become a butterfly.毛毛虫必须经过茧的阶段才能变成蝴蝶。
adj.无限的，不受控制的，无条件的
- They flew over the unlimited reaches of the Arctic.他们飞过了茫茫无边的北极上空。
- There is no safety in unlimited technological hubris.在技术方面自以为是会很危险。
n.食肉动物( predator的名词复数 )；奴役他人者（尤指在财务或性关系方面）
- birds and their earthbound predators 鸟和地面上捕食它们的动物
- The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》
n.囚禁；被俘；束缚
- A zoo is a place where live animals are kept in captivity for the public to see.动物园是圈养动物以供公众观看的场所。
- He was held in captivity for three years.他被囚禁叁年。
n.毛虫( caterpillar的名词复数 )；履带
- Caterpillars eat the young leaves of this plant. 毛毛虫吃这种植物的嫩叶。
- Caterpillars change into butterflies or moths. 毛虫能变成蝴蝶或蛾子。 来自辞典例句
n.蛾，蛀虫
- A moth was fluttering round the lamp.有一只蛾子扑打着翅膀绕着灯飞。
- The sweater is moth-eaten.毛衣让蛀虫咬坏了。
n.蛾( moth的名词复数 )
- The moths have eaten holes in my wool coat. 蛀虫将我的羊毛衫蛀蚀了几个小洞。 来自《简明英汉词典》
- The moths tapped and blurred at the window screen. 飞蛾在窗帘上跳来跳去，弄上了许多污点。 来自《现代英汉综合大词典》
vt.逃避，回避；避开，躲避
- He tried to evade the embarrassing question.他企图回避这令人难堪的问题。
- You are in charge of the job.How could you evade the issue?你是负责人，你怎么能对这个问题不置可否？