PTE听力口语-科学60秒:DNA Testing to Help Sharks

PTE考生目前最大的问题之一就是练习题缺乏。除了有限的基本官方书(PLUS,Testbuilder, OG)之外就没有题了。很多英语基础不是很扎实的同学很难找到练习材料。悉尼文波雅思PTE培训学校专门为澳洲,尤其是悉尼、墨尔本的PTE考生准备了适合PTE听力阅读练习的科学60秒。各位PTE同学可以练习PTE听力中的summarise spoken text和PTE口语中的retell lecture,练习记笔记技巧和复述。

DNA Testing to Help Sharks Keep Fins
In a study in the journal Endangered Species Research, shark fins on sale were shown to be from a specific region in which shark populations have collapsed, evidence that may help change fishing regulations. Cynthia Graber reports

I should start this podcast off with an admissionI have a serious problem with shark fin soup. Fishermen slice the fin off the shark and toss the creature back into the water to die. This happens to millions of sharks around the world, and some of those shark populations are endangered. Scientists have been trying to figure out which shark populations are most at risk by the slashandtoss. Now theres new DNA evidence thats aiding the effort.

Researchers used a tool calledgenetic stock identificationto test samples of 62 scalloped hammerhead shark finsan endangered speciesfrom the Hong Kong fin market. They analyzed the mitochondrial DNA, which is passed down from the mother and is traceable to the sharksbirth waters. Fiftyseven of those sharks came from Atlantic and IndoPacific waters, and 21 percent live in the western atlantic, where sharksnumbers have now collapsed. The results were published online in the journal Endangered Species Research.

Scientists will bring these results to the 2010 Convention on International Trade in Endangered Species meeting. A change in the sharks designation at that meeting could lead to better protection from commercial exploitation.

Cynthia Graber

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