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2014年职称英语理工类教材学习部分内容及解析 13. Hidden Species May Be Surprisingly Common (替换2013年用书理工类阅读理解第四十八篇：Shrinking Water Supply Poses Threat to Peace) Cryptic speciesanimals that appear identical but are genetically quite distantmay 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. 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 biogeographical regions. 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 be many different cryptic species that have low populations and are highly endangered, says Pfenninger. Until the genetic information of all species in at least one taxon is thoroughly studied, no one will know just how many cryptic species exist.It could be as high as 30%, Pfenninger says. | 
