《科学英语：大型恐龙为何不在热带地区生活》由会员分享，可在线阅读，更多相关《科学英语：大型恐龙为何不在热带地区生活（4页珍藏版）》请在金锄头文库上搜索。
1、For more than 30 million years after dinosaurs1 first appeared, they remained inexplicably2 rare near the equator, where only a few small-bodied meat-eating dinosaurs made a living. The long absence at low latitudes3 has been one of the great, unanswered questions about the rise of the dinosaurs.Now
2、 the mystery has a solution, according to scientists who pieced together a detailed4 picture of the climate and ecology more than 200 million years ago at Ghost Ranch5 in northern New Mexico, a site rich with fossils.The findings, reported today in the journal Proceedings6 of the National Academy of
3、 Sciences (PNAS), show that the tropical climate swung wildly with extremes of drought and intense heat.Wildfires swept the landscape during arid7 regimes and reshaped the vegetation available for plant-eating animals.Our data suggest it was not a fun place, says scientist Randall Irmis of the Unive
4、rsity of Utah.It was a time of climate extremes that went back and forth8 unpredictably. Large, warm-blooded dinosaurian9 herbivores werent able to exist close to the equator-there was not enough dependable plant food.The study, led by geochemist Jessica Whiteside, now of the University of Southampt
5、on, is the first to provide a detailed look at climate and ecology during the emergence10 of the dinosaurs.Atmospheric11 carbon dioxide levels then were four to six times current levels. If we continue along our present course, similar conditions in a high-CO2 world may develop, and suppress low-lat
6、itude ecosystems, Irmis says.These scientists have developed a new explanation for the perplexing near-absence of dinosaurs in late Triassic the Triassic was between 248 million and 205 million years ago equatorial settings, says Rich Lane, program director in the National Science Foundations (NSF)
7、Division of Earth Sciences, which funded the research.That includes rapid vegetation changes related to climate fluctuations12 between arid and moist climates and the resulting extensive wildfires of the time.词汇解析：1 dinosaurs n.恐龙( dinosaur 的名词复数 )；守旧落伍的人，过时落后的东西参考例句：The brontosaurus was one of the
8、largest of all dinosaurs. 雷龙是所有恐龙中最大的一种。 来自简明英汉词典Dinosaurs have been extinct for millions of years. 恐龙绝种已有几百万年了。 来自简明英汉词典2 inexplicably adv.无法说明地，难以理解地，令人难以理解的是参考例句：Inexplicably, Mary said she loved John. 真是不可思议，玛丽说她爱约翰。 来自简明英汉词典Inexplicably, she never turned up. 令人不解的是，她从未露面。 来自辞典例句3 latitudes 纬度参考
9、例句：Latitudes are the lines that go from east to west. 纬线是从东到西的线。It was the brief Indian Summer of the high latitudes. 这是高纬度地方的那种短暂的晚秋。4 detailed adj.详细的，详尽的，极注意细节的，完全的参考例句：He had made a detailed study of the terrain.他对地形作了缜密的研究。A detailed list of our publications is available on request.我们的出版物有一份详细的
10、目录备索。5 ranch n.大牧场，大农场参考例句：He went to work on a ranch.他去一个大农场干活。The ranch is in the middle of a large plateau.该牧场位于一个辽阔高原的中部。6 proceedings n.进程，过程，议程；诉讼(程序)；公报参考例句：He was released on bail pending committal proceedings. 他交保获释正在候审。to initiate legal proceedings against sb 对某人提起诉讼7 arid adj.干旱的；(土地)贫瘠的参
11、考例句：These trees will shield off arid winds and protect the fields.这些树能挡住旱风,保护农田。There are serious problems of land degradation in some arid zones.在一些干旱地带存在严重的土地退化问题。8 forth adv.向前；向外，往外参考例句：The wind moved the trees gently back and forth.风吹得树轻轻地来回摇晃。He gave forth a series of works in rapid succession
12、.他很快连续发表了一系列的作品。9 dinosaurian adj.恐龙的，似恐龙的 n.恐龙参考例句：Those who having dinosaurian body is medium grain is in its local the muscle that aardwolf. 有着恐龙身躯的中粮在它的局部显出了土狼的肌肉。 来自互联网10 emergence n.浮现，显现，出现，（植物）突出体参考例句：The last decade saw the emergence of a dynamic economy.最近 10 年见证了经济增长的姿态。Language emerges a
13、nd develops with the emergence and development of society.语言是随着社会的产生而产生，随着社会的发展而发展的。11 atmospheric adj.大气的，空气的；大气层的；大气所引起的参考例句：Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。12 fluctuations 波动，涨落，起伏( fluctuation 的名词复数 )参考例句：He showed the price fluctuations in a statistical table. 他用统计表显示价格的波动。There were so many unpredictable fluctuations on the Stock Exchange. 股票市场瞬息万变。更多英语学习方法：企业英语培训 http:/
