古爬行动物如何适应水生环境
文章来源:未知 文章作者:enread 发布时间:2011-11-18 03:05 字体: [ ]  进入论坛
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Extinct animals hide their secrets well, but an exceptionally well-preserved fossil of an aquatic1(水生的) reptile2(爬行动物) , with traces of soft tissue present, is providing scientists a new window into the behavior of these ancient swimmers. According to the study published in PLoS ONE's Nov. 16 issue, the fossil, characterized by a team led by Johan Lindgren of Lund University in Sweden, is from the mosasaur(沧龙) family, a group of reptiles3 that lived between 65 and 98 million years ago.

The fossil was found in Western Kansas, and was submerged under a shallow sea at the time of the mosasaur's existence. Previous analysis of mosasaur locomotion4 had been limited by a lack of soft tissue fossils, which was crucial for the scientists to truly understand the degree of aquatic adaptation that the creature had achieved. The new findings, which include scales and skin impressions, suggest that the mosasaur was able to minimize its frictional drag(摩擦阻力) in the water. Additional features suggest that it held the front of its body somewhat rigid5 during swimming, leading it to depend on the rear of its body and tail for propulsion(推进) .

According to Dr. Lindgren, this study provides "unique insights into the biology of an extinct group of marine6 lizards7 that became adapted to aquatic environments in a fashion similar to that of the preceding ichthyosaurs ('fish-lizards') and succeeding whales." Thus, these results may have implications for understanding how this group ultimately transformed from land-dwellers to pelagic(浮游的) cruisers in a relatively8 short period of geological time.



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1 aquatic mvXzk     
adj.水生的,水栖的
参考例句:
  • Aquatic sports include swimming and rowing.水上运动包括游泳和划船。
  • We visited an aquatic city in Italy.我们在意大利访问过一个水上城市。
2 reptile xBiz7     
n.爬行动物;两栖动物
参考例句:
  • The frog is not a true reptile.青蛙并非真正的爬行动物。
  • So you should not be surprised to see someone keep a reptile as a pet.所以,你不必惊奇有人养了一只爬行动物作为宠物。
3 reptiles 45053265723f59bd84cf4af2b15def8e     
n.爬行动物,爬虫( reptile的名词复数 )
参考例句:
  • Snakes and crocodiles are both reptiles. 蛇和鳄鱼都是爬行动物。 来自《简明英汉词典》
  • Birds, reptiles and insects come from eggs. 鸟类、爬虫及昆虫是卵生的。 来自《现代汉英综合大词典》
4 locomotion 48vzm     
n.运动,移动
参考例句:
  • By land,air or sea,birds are masters of locomotion.无论是通过陆地,飞越空中还是穿过海洋,鸟应算是运动能手了。
  • Food sources also elicit oriented locomotion and recognition behavior patterns in most insects.食物源也引诱大多数昆虫定向迁移和识别行为。
5 rigid jDPyf     
adj.严格的,死板的;刚硬的,僵硬的
参考例句:
  • She became as rigid as adamant.她变得如顽石般的固执。
  • The examination was so rigid that nearly all aspirants were ruled out.考试很严,几乎所有的考生都被淘汰了。
6 marine 77Izo     
adj.海的;海生的;航海的;海事的;n.水兵
参考例句:
  • Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
  • When the war broke out,he volunteered for the Marine Corps.战争爆发时,他自愿参加了海军陆战队。
7 lizards 9e3fa64f20794483b9c33d06297dcbfb     
n.蜥蜴( lizard的名词复数 )
参考例句:
  • Nothing lives in Pompeii except crickets and beetles and lizards. 在庞培城里除了蟋蟀、甲壳虫和蜥蜴外,没有别的生物。 来自辞典例句
  • Can lizards reproduce their tails? 蜥蜴的尾巴断了以后能再生吗? 来自辞典例句
8 relatively bkqzS3     
adv.比较...地,相对地
参考例句:
  • The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
  • The operation was relatively painless.手术相对来说不痛。
TAG标签: water reptile aquatic
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