西伯利亚发现最古老的家犬化石
文章来源:未知 文章作者:enread 发布时间:2013-03-14 05:32 字体: [ ]  进入论坛
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Analysis of DNA1 extracted from a fossil tooth recovered in southern Siberia confirms that the tooth belonged to one of the oldest known ancestors of the modern dog, and is described in research published March 6 in the open access journal PLOS ONE by Anna Druzhkova from the Institute of Molecular2 and Cellular3 Biology, Russian Federation4, and colleagues from other institutions. Human domestication5 of dogs predates the beginning of agriculture about 10,000 years ago, but when modern dogs emerged as a species distinct from wolves is still unclear. Although some previous studies have suggested that this separation of domestic dogs and wolves occurred over 100,000 years ago, the oldest known fossils of modern dogs are only about 36,000 years old.
 
The new research published today evaluates the relationship of a 33,000 year old Siberian fossil to modern dogs and wolves based on DNA sequence. The researchers found that this fossil, named the 'Altai dog' after the mountains where it was recovered, is more closely related to modern dogs and prehistoric6 canids found on the American continents than it is to wolves.
 
They add, ""These results suggest a more ancient history of the dog outside the Middle East or East Asia, previously7 thought to be the centers where dogs originated."


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1 DNA 4u3z1l     
(缩)deoxyribonucleic acid 脱氧核糖核酸
参考例句:
  • DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
  • Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。
2 molecular mE9xh     
adj.分子的;克分子的
参考例句:
  • The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
  • For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时,分子的碰撞就停止了。
3 cellular aU1yo     
adj.移动的;细胞的,由细胞组成的
参考例句:
  • She has a cellular telephone in her car.她的汽车里有一部无线通讯电话机。
  • Many people use cellular materials as sensitive elements in hygrometers.很多人用蜂窝状的材料作为测量温度的传感元件。
4 federation htCzMS     
n.同盟,联邦,联合,联盟,联合会
参考例句:
  • It is a federation of 10 regional unions.它是由十个地方工会结合成的联合会。
  • Mr.Putin was inaugurated as the President of the Russian Federation.普京正式就任俄罗斯联邦总统。
5 domestication a412c94ddc4dddbce0e57281001e9ede     
n.驯养,驯化
参考例句:
  • The first was the domestication of animals. 第一个阶段是驯养动物。 来自《简明英汉词典》
  • In northwestern China, there is no evidence for endemic domestication of any animals. 在中国西北,没有任何当地动物驯化的迹象。 来自辞典例句
6 prehistoric sPVxQ     
adj.(有记载的)历史以前的,史前的,古老的
参考例句:
  • They have found prehistoric remains.他们发现了史前遗迹。
  • It was rather like an exhibition of prehistoric electronic equipment.这儿倒像是在展览古老的电子设备。
7 previously bkzzzC     
adv.以前,先前(地)
参考例句:
  • The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
  • Let me digress for a moment and explain what had happened previously.让我岔开一会儿,解释原先发生了什么。
TAG标签: dog fossil modern
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