首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
In many parts of the world, alien species are harming the environment and causing other problems. An alien species is a species
In many parts of the world, alien species are harming the environment and causing other problems. An alien species is a species
admin
2021-12-31
40
问题
In many parts of the world, alien species are harming the environment and causing other problems. An alien species is a species of plant or animal that has moved from its original home to a new area. Sometimes people have intentionally introduced the new species; sometimes it arrives accidentally, as a side effect of international trade. In its new location, the alien species has no natural enemies, so it can grow and multiply without limit. Over time—sometimes decades, sometimes a few years—the new species takes living space and food away from the native plants and animals. The result can mean drastic change in the natural landscape and problems for people.
The tiger mosquito is an example of an alien species. This kind of mosquito is common in Asia, but in recent years it has moved to parts of southern Europe. Scientists believe that the eggs of this insect probably arrived inside some car tires that were filled with water. In a few years, the mosquitoes multiplied and spread over large areas of Italy and other countries. Tiger mosquitoes can reproduce faster than common European mosquitoes, so they quickly replaced a large percentage of the native mosquitoes. Though they don ’ t cause serious disease in humans, tiger mosquitoes are a serious nuisance. They are far more aggressive than common European mosquitoes, and the effects of their bites are worse.
Another example of a different kind of animal that has recently moved to another continent is the zebra mussel. This small shellfish was first discovered in the Great Lakes of North America in 1986. It may have come over from Rvrssia on a cargo ship. In a very few years, zebra mussels had spread over all the Great Lakes and into many important rivers. They have grown into thick masses, covering many areas of lakes or river bottoms. They have also covered and closed up pipes of power stations and water treatment centers.
Among the many examples of alien species of mammals that have caused damage is the Indian mongoose. This animal was brought to Hawaii in the 1800s to kill rats in sugarcane fields. Since then, they have grown in numbers so that today they are a major threat to bird life on the islands. One of the mongoose’ s favorite foods, in fact, is birds’ eggs. Thus, the mongoose has caused great damage to poultry farmers in Hawaii, and it has greatly reduced the numbers of many native bird species. Many of these species, which are unique to the islands, are now at risk of extinction.
Where was the zebra mussel first discovered?
选项
答案
It was first discovered in the Great Lakes of North America.
解析
文章第三段第二句提到,小型贝类最早于1986年在北美五大湖发现。由此可知本题答案。
转载请注明原文地址:https://kaotiyun.com/show/1EVK777K
本试题收录于:
D类竞赛(专科)题库大学生英语竞赛(NECCS)分类
0
D类竞赛(专科)
大学生英语竞赛(NECCS)
相关试题推荐
Televisioncanbeawonderfullearningtool.Thirty-oddyearsago,"SesameStreet,""TheElectricCompany"and"Mr.Rogers’Neig
(1)The35-year-oldBeijingwomaniswatchinganadshowingagianttelevisionmadebytheChinesecompanyHaier.Astreamofint
(1)The35-year-oldBeijingwomaniswatchinganadshowingagianttelevisionmadebytheChinesecompanyHaier.Astreamofint
PassageThreeWhatdobirdselovefrom,consideringArchaeopteryxatransitionalspecies?
(1)Becauseofcomputersandcabletelevision,themembersoftheaudiencewillsoonbemorethanwatchers.Theywillbeableto
Weallseeandhearaboutextraordinarypeoplearoundusandwonderwhywecan’tbemorelikethem.Sometimeswechuckthatnoti
Weallseeandhearaboutextraordinarypeoplearoundusandwonderwhywecan’tbemorelikethem.Sometimeswechuckthatnoti
Whales,severalspeciesofwhichfaceextinction,havebecomesubjectsofconsiderablesympathy.Thesearetherecordedvoiceso
Whales,severalspeciesofwhichfaceextinction,havebecomesubjectsofconsiderablesympathy.Thesearetherecordedvoiceso
Whales,severalspeciesofwhichfaceextinction,havebecomesubjectsofconsiderablesympathy.Thesearetherecordedvoiceso
随机试题
下列关于老年性阴道炎临床表现,不正确的是
A、雷尼替丁B、西咪替丁C、罗沙替丁D、尼扎替丁E、法莫替丁不易透过血脑屏障,中枢神经不良反应较少的药物是()
背景资料:2012年1月8日20时许,江面风大流急,某航道治理工程一碇泊式挖泥船正紧张施工。在进行调整船舶钢丝绳时,一名水手被钢丝绳反弹击中,落水失踪。事后经调查,该水手未穿救生衣,在调整钢丝绳作业时站位不对,违反甲板操作规程。以下不符合水上作业安全管
(2011年)热线风速仪的测量原理是()。
《银行业监督管理法》规定,银行业金融机构应当按照规定如实向社会公众披露()。
国际上通行的“骆驼评级制度”内容包括()。
注册会计师负责审计甲公司2012年度财务报表。在设计识别固定资产可能存在的错报风险时,拟向该公司管理层及内部员工询问。在向生产负责人询问固定资产的相关情况时,注册会计师最有可能了解到固定资产的相关事项是()。
中原大战
感觉阈限包括
元朝有一部由地方官吏自行编制的法律汇编,其名称是()。
最新回复
(
0
)