职称英语考试理工类的AB级阅读理解精讲(3)

　　Hidden Species May Be Surprisingly Common 　　Cryptic species animals that appear identical but are genetically quite distant一may be much more widespread than previously thought. The findings could have major implications in areas ranging from biodiversity estimates and wildlife management，to our understanding of infectious diseases and evolution. 　　Scientists had previously speculated that cryptic species were predominantly found in insects and reptiles，and were more likely to occur in tropical rather than temperate regions. Species that are seemingly widespread and abundant could in reality he many different cryptic species that have low populations and are highly endangered, says Henninger. Until the genetic information of all species. in at least one texon is thoroughly studied, no one will know just how many cryptic species exist. It could be as high. as 30%，Pfenninger says 　　Sampling as many individuals as possible, scientists hope to complete work on all fish and birds in another 5 to 10 years. Once either of these taxonumic groups is completed. Pfenninger says researchers will be able to decide how many cryptic species exist throughout the animal kingdom. 　　The reclassifications are more than an academic exercise: They define populations that have evolved independently of each other and whom genetic differences that have evolved independently of each other and whose genetic differences can have significant consequences. 　　1，Which of the following about the significance of the research on cryptic species is NOT true? 　　B The results of the research can help the development of biodiversity estimates. 　　D. The results of the research can help our understanding of survival of the fittest. 　　A They occurred in equal numbers in all biogeographical regions 　　C They were likely to be in tropical rather than temperate regions 　　3, 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.