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。
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