梁龙头骨随着成长而发生形变-凯发k8官网

梁龙头骨随着成长而发生形变
文章来源:未知 文章作者:meng 发布时间:2010-04-02 00:28 字体: [ ] 
(单词翻译:双击或拖选)

the 1 of a 2(青少年的,幼稚的) sauropod(蜥脚类动物) 3, rediscovered in the collections of pittsburgh's carnegie museum of natural history, 4(阐明,说明) that some sauropod species went through drastic(激烈的,猛烈的) changes in skull shape during normal growth. university of michigan paleontologists(古生物学者) john whitlock and jeffrey wilson, along with matthew lamanna from the carnegie museum, describe their find in the march issue of the journal of vertebrate paleontology.

the fossil offers a rare chance to look at the early life history of diplodocus, a 150 million-year-old sauropod from western north america.

"adult sauropod 5 are rare, but juvenile skulls are even rarer," said whitlock, a doctoral candidate in the u-m museum of paleontology. "what we do know about the skulls of sauropods like diplodocus has been based 6 on adults so far."

"diplodocus(梁龙) had an unusual skull," said wilson, an assistant professor in the department of geological sciences and an assistant curator at the u-m museum of paleontology. "adults had long, square snouts(鼻子) , unlike the rounded or 7 snouts of other sauropods. up until now, we assumed 8 did too."

the small diplodocus skull, however, suggests that major changes occurred in the skull throughout the animal's life.

"although this skull is plainly that of a juvenile diplodocus, in many ways it is quite different from those of the adults," whitlock said. "like those of most young animals, the eyes are proportionally larger, and the face is smaller. what was unexpected was the shape of the snout—it appears to have been quite pointed(锐利的,突出的) , rather than square like the adults. this gives us a whole new perspective on what these animals may have looked like at different points in their lives."

the researchers believe these changes in skull shape may have been tied to feeding behavior, with adults and juveniles eating different foods to avoid competition. young diplodocus, with their narrower snouts, may also have been choosier 9, selecting high quality plant parts.

the discovery also highlights the importance of museum collections for paleontological(古生物学的) research.

"fossils like this are a great example of why natural history museums like ours put so much time and effort into caring for our collections, said lamanna, an assistant curator(馆长,监护人) of vertebrate(脊椎动物的) paleontology at carnegie museum of natural history. "this little diplodocus skull was discovered in 1921, and more than 80 years passed before we recognized its significance. if the carnegie museum hadn't preserved it for all that time, the important insight it has provided into the growth and ecology of this dinosaur would have been lost."

the actual juvenile diplodocus skull, as well as a 10 restored, mounted skeleton of an adult, is on display in carnegie museum of natural history's "11 in their time" exhibition.



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1 cetyo     
n.头骨;颅骨
参考例句:
  • the skull bones fuse between the ages of fifteen and twenty-five.头骨在15至25岁之间长合。
  • he fell out of the window and cracked his skull.他从窗子摔了出去,跌裂了颅骨。
2 okey2     
n.青少年,少年读物;adj.青少年的,幼稚的
参考例句:
  • for a grown man he acted in a very juvenile manner.身为成年人,他的行为举止显得十分幼稚。
  • juvenile crime is increasing at a terrifying rate.青少年犯罪正在以惊人的速度增长。
3 xusxp     
n.恐龙
参考例句:
  • 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。
4 a03402300df9f3e3716d9eb11aae5782     
给…加插图( illustrate的第三人称单数 ); 说明; 表明; (用示例、图画等)说明
参考例句:
  • this historical novel illustrates the breaking up of feudal society in microcosm. 这部历史小说是走向崩溃的封建社会的缩影。
  • alfred adler, a famous doctor, had an experience which illustrates this. 阿尔弗莱德 - 阿德勒是一位著名的医生,他有过可以说明这点的经历。 来自中级百科部分
5 d44073bc27628272fdd5bac11adb1ab5     
颅骨( skull的名词复数 ); 脑袋; 脑子; 脑瓜
参考例句:
  • one of the women's skulls found exceeds in capacity that of the average man of today. 现已发现的女性颅骨中,其中有一个的脑容量超过了今天的普通男子。
  • we could make a whole plain white with skulls in the moonlight! 我们便能令月光下的平原变白,遍布白色的骷髅!
6 entirely     
ad.全部地,完整地;完全地,彻底地
参考例句:
  • the fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
  • his life was entirely given up to the educational work. 他的一生统统献给了教育工作。
7 il8zb4     
adj.尖的,直截了当的
参考例句:
  • he gave me a very sharp pointed pencil.他给我一支削得非常尖的铅笔。
  • she wished to show mrs.john dashwood by this pointed invitation to her brother.她想通过对达茨伍德夫人提出直截了当的邀请向她的哥哥表示出来。
8 257c9101f917ec8748aa5fc520c6a9e3     
n.青少年( juvenile的名词复数 );扮演少年角色的演员;未成年人
参考例句:
  • do you think that punishment for violent crimes should be the same for juveniles and adults? 你对暴力犯罪的惩罚对于青少年和成人应一样吗? 来自生活英语口语25天快训
  • juveniles should we not exactly in need of such strength and conviction? 少年的我们难道不正是需要这种力量和信念吗? 来自互联网
9 b559db93c279b7e4886705cb45f7ca9c     
浏览器
参考例句:
  • three-layer architecture is a model made up of browser, web server and background database server. 这种体系结构是由browser、web server、database server组成的浏览器/web服务器/后台数据库服务器三层模型。 来自互联网
  • another excellent approach is to abandon the browser entirely and, instead, create a non-browser-based, internet-enabled application. 另一个非常好的方法是干脆放弃浏览器,取而代之,创建一个不基于浏览器,但却是基于互联网的应用。 来自about face 3交互设计精髓
10 gfuzd     
adv.完全地,全部地,彻底地;充分地
参考例句:
  • the doctor asked me to breathe in,then to breathe out fully.医生让我先吸气,然后全部呼出。
  • they soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。
11 87f9c39b9e3f358174d58a584c2727b4     
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 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》
tag标签: species dinosaur
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