Hidden Species May Be Surprisingly Common Reports of cryptic species have increased dramatically over the past two decades with the advent of relatively inexpensive DNA sequencing technology.Markus Pfenninger and Klaus Schwenk,of the Goethe-Universitat,in Frankfurt1,Germany,analyzed all known data on cryptic animal species and discovered that they are found in equal proportions throughout all major branches of the animal kingdom and occur in equal numbers in all biogeographieal regions. Im extremely surprised by their results, says Alex Smith of the University of Guelph2 in Ontario3,Canada.Its a call to arms to keep doing the broad kind of genetic studies that we are doing. Examples of cryptic species include the African elephant. A 2001 study found the elephants were actually two genetically distinct,non-interbreeding species,the African bush elephant and the African elephant. The species are currently listed as vulnerable and threatened,respectively,by the World Conservation Union 4. In the early 1900s misidentification of mosquito species based on morphology confused attempts to control malaria in Europe.Ultimately,what was thought to be a single species was actually made up of six sibling species,only three of which transmitted the disease.The basic unit in biology is always the species,and you have to know what you are dealing with, Pfenninger says.Much previous research is now no longer used,he says,because it is not clear what species was being studied. the Goethe-Universitat in Frankfurt:德国法兰克福大学,即Johann Wolfgang Goethe- Universitat Frankfurt am Main,位于美因和莱茵两河汇流处的法兰克福。 Ontario:安大略。加拿大中东部的一个省。 练习: is NOT true? B The restllts of the research can help the development of biodiversityestimates. D The results of the research can help our understanding of survival of thefittest. A They occurred in equal numbers in all biogeographical regions. C They were likely to be in tropical rather than temperate regions. Do scientists know how many cryptic species exist? B Yes,they do. D They will never know the answer. A The WCU are interbreeding those elephants. C They are two genetically distant species. People were confused in their attempts to control malaria in Europe in the early1900s,because scientists B thought only three mosquito species transmitted disease. D did not know what species was being studied. 2. D 短文的第二段第二句描述的是科学家目前的研究结果,第三段描述的是科学家在这之前对于cryptic species的理解。本题用的是过去式,问的是过去的状况,因此,答案在第三段中,B和C是答案,所以D是正确选择。 C 答案在第六段中。该段举了非洲大象为例,说明什么是cryptic species。第六段的句子A 2001 study found the elephants were actually two genetically distinct,non- interbreeding spemes是选择C的依据。选项A不对,the WCU并没有杂交繁殖这两种象。选项B不对,短文说这两种象是非杂交物种。选项D的内容短文中找不到。
从A到Z畅谈美国流行文化:an arm and a leg
从A到Z畅谈美国流行文化:Backseat driver
双语美文:让自己成为自己的那道光
从A到Z畅谈美国流行文化:Get it over with
你知道如何更高效地学习吗?
从A到Z畅谈美国流行文化:Catch-22
英美文化节日:汤姆索亚日的来历故事
从A到Z畅谈美国流行文化:all over
从A到Z畅谈美国流行文化:Dutch
西方的“拥抱文化”,你了解多少
从A到Z畅谈美国流行文化:Eight-six86
从A到Z畅谈美国流行文化:Excuse my French
5.8欢舞节日,让你一次跳到痛快
揭秘五个奇怪却实用的健康小贴士
植树节的来历故事简介
中外文化谈:如何做个有礼貌的旅行者(下)
英美文化史:圣诞节的故事
从A到Z畅谈美国流行文化:Eat crow
美国的恶搞资讯文化,你受得了吗?
中外文化大不同,盘点十个极容易发生的误会(上)
接吻的5大妙处,你知道是什么吗?
从A到Z畅谈美国流行文化:Fair
十件你不知道的感恩节的事(下)
从A到Z畅谈美国流行文化:Bark up the wrong tree
51国际劳动节的来历故事简介
英国文化介绍:英式下午茶的前世今生
从A到Z畅谈美国流行文化:been there
从A到Z畅谈美国流行文化:Bells and whistles
男朋友一定喜欢的五大经典礼物盘点
从A到Z畅谈美国流行文化:Drop-dead gorgeous
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |