首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Once found almost entirely in the western United States and in Asia, dinosaur fossils are now being discovered on all seven cont
Once found almost entirely in the western United States and in Asia, dinosaur fossils are now being discovered on all seven cont
admin
2012-05-18
82
问题
Once found almost entirely in the western United States and in Asia, dinosaur fossils are now being discovered on all seven continents. A host of new revelations emerged in 1998 that promise to reshape scientists’ views of dinosaurs, including what they looked like and when and where they lived.
It is doubtful that Tyrannosaurus Rex had lips or that Triceratops had cheeks, says Lawrence Witmer, an assistant professor of anatomy at Ohio University in Athens, Ohio. He reached its conclusions by using high-tech computerized axial tomography (CT or CAT) scans along with comparative anatomy studies. For example, the theory that Triceratops and similar dinosaur species had cheeks was based on past comparisons with mammals such as sheep. But Winner’s careful analysis found the structure of the triceratops jaw and skull made it more likely that Triceratops had a beak like that of an eagle. Winner said that scientists should use birds and crocodiles as models when researching the appearance of dinosaurs.
In early October scientists announced that they had confirmed the discovery of a new type of ceratopsian dinosaur. The dinosaur’s bones, found in New Mexico in 1996, are forcing paleontologists to rethink their theories about when ceratopsians migrated to what is now North America.
Scientists previously thought that ceratopsians, the group that included the well-known Triceratops, arrived in North America from Asia between 70 million and 80 million years ago. During this time, the late Cretaceous Period, the earth’s two supercontinents—Laurasia in the north and Gondwanaland in the south—were in the process of pulling apart, cutting dinosaur populations off from each other and interrupting migratory patterns.
The fossilized bones, found by paleontologist Doug Wolfe of the Mesa Southwest Museum in Arizona, date to about 90 million years ago. This could mean that ceratopsians originated in North America and migrated to Asia rather than the reverse, paleontologists said.
An expedition from the Universities of Alaska in Anchorage and Fairbanks has discovered a region in remote northern Alaska so rich in fossilized dinosaur tracks that team members dubbed it the "dino expressway". The trampled area was found during the summer of 1998 on Alaska’s North Slope near the Brooks Range.
The team found 13 new track sites and made casts from the prints of five different types of dinosaurs. The rock in which the prints were found dates to more than 100 million years ago, or about 25 million years older than the previously discovered signs of dinosaurs in the Arctic region. Paleontologists said that the new findings provide important evidence that dinosaurs migrated between Asia and North America during the early and mid-Cretaceous Period, before Asia split off into its own continent.
Two rich fossil sites in the hills of Bolivia have been recently discovered, exciting paleontologists and dinosaur buffs. This discovery includes one of the most spectacular dinosaur trackways ever found.
The discovery of a large site in the mountain region of Kila Kila in southern Bolivia was announced in early October. Here scientists found the tracks of at least two unknown species of dinosaur. These included a large quadruped (four-footed) dinosaur that was probably about 20 m (about 70 ft) long.
The other site, located not far from the Bolivian city of Sucre, was uncovered in a cement quarry by workers several years ago but was not brought to paleontologists’ attention until the middle of 1998. The site features a vertical wall covered with thousands of dinosaur prints representing more than 100 different species. The tracks date back to between 65 million and 70 million years ago. Since dinosaurs are believed to have died out around 65 million years ago, the prints were likely made by some of the last dinosaurs on earth. Paleontologists hope to study the site and learn about the diet and physical characteristics of the dinosaurs that are represented there.
Witmer’s research leads people to believe______.
选项
A、Tyrannosaurus Rex had lips and Triceratops had cheeks
B、dinosaurs might have looked like mammals such as sheep
C、dinosaurs might not have looked like what we thought
D、dinosaurs must have looked like birds or crocodiles
答案
C
解析
细节题。根据第一段最后一句“new revelations…to reshape scientist’s views of dinosaurs,including what they looked like新的发现将改变科学家对恐龙长相的认识”即可基本判断C为答案,再结合第二、三段的主要内容可知,Witmer的研究表明恐龙的长相与过去科学家对恐龙长相的推测有很大差异。
转载请注明原文地址:https://kaotiyun.com/show/mAiO777K
0
专业英语八级
相关试题推荐
Ablindbabyisdoublyhandicapped.Notonlyisitunabletosee,butbecauseitcannotreceivethevisualstimulusfromitsenv
TheFutureofPCMarketThefirstDevelopersConferenceinChinamarksamajormilestoneforMicrosoft,becausethesuccesso
Whichofthefollowingisacompoundword?
A、theirmodelpermitsschooltoclustertheirresources,personnelandfundsB、theychargelowertuitionC、theyaresmallerD、th
A、blowupanapartmentbuildingintheU.S.B、gainaccesstosufficientnaturalgasandexplosivesC、prepareforaterroristat
Themagnetfortourists,thesymbolofthecity,Manhattanisprobablythemostdeceptiveoftheboroughstooutsiderswhogener
Accordingtothepassage,mostIcelandersviewlandassomethingof______.WhatisIceland’sold-agedadvocates’feelingtoward
A、willanswertheirshort-termneedsB、doesnotrequireimmediateinvestmentC、willhelptheirplanningproceduresD、focuseson
Sincethestartofthisyear,Google’ssharepricehasfallensteadilyasinvestorshavebeguntofretaboutitslonger-termpro
WhatcanweknowfromthenewsaboutMartinKippenberger?
随机试题
国际私法
对外宣布我国的对外政策加强中国与外国的信息交流这一外事行政管理内容的执行者是()
根据《测绘作业证管埋规定》,测绘人员遗失测绘作业证,应当立即向()报告并说明。
原建设部、国家工商管理总局联合颁发《建设工程设计合同(示范文本)》是在()。
外购固定资产的成本包括()。
某汽车厂商宣称,其新推出的汽车已经通过了各种撞击测试,当车祸发生时,乘车人的安全可以得到充分保障。但是也有人质疑,仅通过撞击测试不足以证明汽车是安全的。以下哪项如果为真,则不能支持这种质疑?()
国务院对公安部发布的不适当的命令、指示和规章有权()。
“手推磨产生的是封建主为首的社会,蒸汽磨产生的是工业资本家为首的社会”这句话是说()。
2013年我国60岁以上人口达2亿,本世纪30年代中将达4亿。面对严峻的人口形势.党的十八届三中全会决定将实施30多年的“一胎化”政策调整为“单独夫妻可生二胎”政策。这一调整的哲学依据是:
模块A的功能为:从数据库中读出产品信息,修改后存回数据库,然后将修改记录写到维护文件中。该模块内聚类型为(38)内聚。以下关于该类内聚的叙述中,正确的是(39)。(39)
最新回复
(
0
)