早期鸟类化石的性别鉴定
文章来源:未知 文章作者:enread 发布时间:2013-01-23 07:00 字体: [ ]  进入论坛
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In a paper published in Nature Communications on January 22, 2013, a team of paleontologists(古生物学者) including Dr. Luis Chiappe, Director of the Natural History Museum of Los Angeles County's (NHM) Dinosaur1 Institute, has discovered a way to determine the sex of an avian dinosaur species. Confuciusornis sanctus, a 125-million-year-old Mesozoic bird, had remarkable2 differences in plumage -- some had long, almost body length ornamental3 tail feathers, others had none -- features that have been interpreted as the earliest example of avian courtship. However, the idea that male Confuciusornis birds had ornamental plumage, and females did not, has not been proven until now. Chiappe and the team studied hundreds of Confuciusornis fossils unearthed4 from rocks deposited at the bottom of ancient lakes in what is today northeastern China and found undisputed evidence of the gender5 difference: medullar(骨髓的) bone.
 
Chiappe conducted the study with Anusuya Chinsamy of the Department of Biological Sciences, University of Cape6 Town, South Africa; Jesús Marugán-Lobón of Madrid's Universidad Autonóma, Cantoblanco; Gao Chunling and Zhang Fengjiao of the Dalian Natural History Museum in China.
 
"Our discovery provides the first case of sex identification in an ancient bird, an animal closely related to dinosaurs7, such as the famous Velociraptor," said Chiappe. "When people visit dinosaur exhibits, they often want to know if the skeletons are male or female. We have nicknames like Thomas and Sue, but of all the thousands of skeletons of dinosaurs or early birds found around the world, only the sex of a few has been determined8."
 
According to Chinsamy, the bone histologist(组织学家) on the team, "Just like modern hens, female Confuciusornis birds that lived 125 million years ago deposited this special bone inside their long bones, and then used it to make the calcium-rich eggshells." Finding such tissue -- present during a short period of time in reproductively active females -- in a specimen9 that lacked long feathers proved that those birds without ornamental plumage are females.
 
"This now permits us to assess gender differences in growth and development of this Mesozoic bird," she said.


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1 dinosaur 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。
2 remarkable 8Vbx6     
adj.显著的,异常的,非凡的,值得注意的
参考例句:
  • She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
  • These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。
3 ornamental B43zn     
adj.装饰的;作装饰用的;n.装饰品;观赏植物
参考例句:
  • The stream was dammed up to form ornamental lakes.溪流用水坝拦挡起来,形成了装饰性的湖泊。
  • The ornamental ironwork lends a touch of elegance to the house.铁艺饰件为房子略添雅致。
4 unearthed e4d49b43cc52eefcadbac6d2e94bb832     
出土的(考古)
参考例句:
  • Many unearthed cultural relics are set forth in the exhibition hall. 展览馆里陈列着许多出土文物。
  • Some utensils were in a state of decay when they were unearthed. 有些器皿在出土时已经残破。
5 gender slSyD     
n.(生理上的)性,(名词、代词等的)性
参考例句:
  • French differs from English in having gender for all nouns.法语不同于英语,所有的名词都有性。
  • Women are sometimes denied opportunities solely because of their gender.妇女有时仅仅因为性别而无法获得种种机会。
6 cape ITEy6     
n.海角,岬;披肩,短披风
参考例句:
  • I long for a trip to the Cape of Good Hope.我渴望到好望角去旅行。
  • She was wearing a cape over her dress.她在外套上披着一件披肩。
7 dinosaurs 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》
8 determined duszmP     
adj.坚定的;有决心的
参考例句:
  • 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。
9 specimen Xvtwm     
n.样本,标本
参考例句:
  • You'll need tweezers to hold up the specimen.你要用镊子来夹这标本。
  • This specimen is richly variegated in colour.这件标本上有很多颜色。
TAG标签: species dinosaur sex
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