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。墨尔本文波雅思PTE培训学校专门为墨尔本，悉尼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。废话少说，下面开始
60秒科学：Biggest Mass Extinction Was Fastest, Too
听力内容：
60秒科学节目（SSS）是科学美国人网站的一套广播栏目，英文名称：Scientific American – 60 Second Science,节目内容以科学报道为主，节目仅一分钟的时间，主要对当今的科学技术新发展作以简明、通俗的介绍，对于科学的发展如何影响人们的生活环境、健康状况及科学技术，提供了大量简明易懂的阐释。
It was the largest of the five major mass extinctions in Earth’s history—well before the dinosaur-killer 66 million years ago. What’s called the End Permian extinction, 252 million years ago, wiped out 96 percent of aquatic species and 70 percent of species on land. Scientists have been trying to gauge the time frame of the extinction, in the hopes of determining its causes.
Now researchers say it’s the fastest mass extinction known.
Using new tools and models—including a fresh analysis of rock formations in China—the researchers determined that the extinction took only about 60,000 years. That’s incredibly quick by geological standards, and is more than 10 times faster than previous estimates.
The report is in the Proceedings of the National Academy of Sciences. [Seth D. Burgess, Samuel Bowring and Shu-zhong Shen, High-precision timeline for Earth’s most severe extinction]
Study author Samuel Bowring from M.I.T. says they can’t yet compare the speed of the previous extinction to the extinction rates caused by human activities today. But, he says, their research is starting to help reveal how past environmental changes that influenced extinctions—such as levels of carbon dioxide in the atmosphere—compare to the changes in those levels seen today. In the midst of what many call the sixth extinction.
—Cynthia Graber
