科学美国人60秒 SSS 2014-2-24
时间：2018-12-24 作者：英语课 分类：2014年Scientific American(二)月
It was the largest of the five major mass extinctions in earth's history, well before the dinosaur 2 killer 3 66 million years ago. What's called the end Permian extinction 1 252 million years ago, wiped out 96% of aquatic 4 species and 70% of species on land. Scientists have been trying to gauge 5 the time of the extinction and they hope to determine its causes. Now researchers say it's the fastest mass extinction known. Using new tools and models, including a fresh analysis of reference in China, the researchers determined 6 that the extinction took only about 60,000 years. That's incredibly quick by geological standards, and it's more than ten times faster than previous estimates. The report is the preceding of the national academy sciences. Study author Simuel Aron from MIT says they can't yet compare the speed of the previous extinction to the extinction rates raised by human activities today. But he says there are researchers studying to help reveal how past environmental changes that influence 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 called the sixth extinction.
- The plant is now in danger of extinction.这种植物现在有绝种的危险。
- The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。
- Are you trying to tell me that David was attacked by a dinosaur?你是想要告诉我大卫被一支恐龙所攻击？
- He stared at the faithful miniature of the dinosaur.他凝视著精确的恐龙缩小模型。
- Heart attacks have become Britain's No.1 killer disease.心脏病已成为英国的头号致命疾病。
- The bulk of the evidence points to him as her killer.大量证据证明是他杀死她的。
- Aquatic sports include swimming and rowing.水上运动包括游泳和划船。
- We visited an aquatic city in Italy.我们在意大利访问过一个水上城市。
- Can you gauge what her reaction is likely to be?你能揣测她的反应可能是什么吗？
- It's difficult to gauge one's character.要判断一个人的品格是很困难的。
- I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
- He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。