南极蓝鲸的生物多样性奇高-凯发k8官网

南极蓝鲸的生物多样性奇高
文章来源:未知 文章作者:enread 发布时间:2012-03-08 03:33 字体: [ ] 
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more than 99 percent of antarctic blue whales were killed by commercial whalers during the 20th century, but the first circumpolar(极地附近的) 1 study of these critically endangered whales has found a surprisingly high level of diversity among the surviving population of some 2,200 individuals. that, says lead author angela sremba of oregon state university, may 2 well for their future recovery.

results of the study have just been published in the open-access journal, plos one. as part of the study, the researchers examined 218 biopsy samples collected from living antarctic blue whales throughout the southern ocean from 1990 to 2009, through a project 3 by the international whaling commission.

the genetic survey revealed a "surprisingly high" level of diversity that may help the population slowly 4 from its catastrophic decimation(大批杀害) by whalers.

"fewer than 400 antarctic blue whales were thought to have survived when this population was protected from commercial hunting in 1966," 5 sremba, who conducted the research as part of her master's degree with the 6 mammal institute at osu's hatfield marine science center. "but the exploitation period, though intense, was brief in terms of years, so the whales' long lifespans and 7 generations may have helped retain the diversity."

"in fact," she added, "some of the antarctic blue whales that survived the genetic 8 may still be alive today."

prior to whaling antarctic blue whales were thought to number about 250,000 individuals -- a total that dwindled(减少,变小) to fewer than 400 animals by 1972 when blue whales were last killed by illegal 9 whaling. blue whales are thought to be the largest animals ever to have lived on earth, said osu's scott 10, associate director of the marine mammal institute and an author on the study -- and the antarctic blue whales were even larger than their cousins in other oceans.

"these animals are very long-lived -- maybe 70 to 100 years -- and they can grow to a length of more than 100 feet and weigh more than 330,000 pounds," he said. "there is a jawbone(颚骨) in a museum in south africa that takes up most of the lobby. this is one reason they were so intensively exploited; they were the most valuable whales to hunt."



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1 pgixp     
adj.遗传的,遗传学的
参考例句:
  • it's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
  • each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。
2 twoz8     
v.预示
参考例句:
  • these figures do not bode well for the company's future.这些数字显示出公司的前景不妙。
  • his careful habits bode well for his future.他那认真的习惯预示著他会有好的前途。
3 72452d15f78aec5878c1559a1fbb5383     
adj.协调的
参考例句:
  • the sound has to be coordinated with the picture. 声音必须和画面协调一致。
  • the numerous existing statutes are complicated and poorly coordinated. 目前繁多的法令既十分复杂又缺乏快调。 来自英汉非文学 - 环境法 - 环境法
4 yatz1     
v.弹回;n.弹回,跳回
参考例句:
  • the vibrations accompanying the rebound are the earth quake.伴随这种回弹的振动就是地震。
  • our evil example will rebound upon ourselves.我们的坏榜样会回到我们自己头上的。
5 5n4zxc     
adj.著名的,知名的
参考例句:
  • the local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
  • jim is noted for arriving late for work.吉姆上班迟到出了名。
6 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 gmqz4t     
adj./n.交迭(的)
参考例句:
  • there is no overlapping question between the two courses. 这两门课程之间不存在重叠的问题。
  • a trimetrogon strip is composed of three rows of overlapping. 三镜头摄影航线为三排重迭的象片所组成。
8 urfyn     
n.瓶颈口,交通易阻的狭口;妨生产流程的一环
参考例句:
  • the transportation bottleneck has blocked the movement of the cargo.运输的困难阻塞了货物的流通。
  • china's strained railroads already become a bottleneck for the economy.中国紧张的铁路运输已经成为经济增长的瓶颈。
9 sw9wr     
adj.苏联的,苏维埃的;n.苏维埃
参考例句:
  • zhukov was a marshal of the former soviet union.朱可夫是前苏联的一位元帅。
  • germany began to attack the soviet union in 1941.德国在1941年开始进攻苏联。
10 wytz62     
n.面包师
参考例句:
  • the baker bakes his bread in the bakery.面包师在面包房内烤面包。
  • the baker frosted the cake with a mixture of sugar and whites of eggs.面包师在蛋糕上撒了一层白糖和蛋清的混合料。
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