锐刺大口虫奇异的交配习惯
文章来源:未知 文章作者:enread 发布时间:2015-07-02 06:04 字体: [ ]  进入论坛
(单词翻译:双击或拖选)
Failing to find a mating partner is a dent1 to the reproductive prospects2 of any animal, but in the flatworm species Macrostomum hystrix it might involve a real headache. Zoologists3 from the Universities of Basel and Bielefeld have discovered the extraordinary lengths to which this animal is willing to go in order to reproduce - including apparently4 injecting sperm5 directly into their own heads. The academic journal Proceedings6 of the Royal Society B has published their findings. The absence of a mate usually spells disaster for sexually reproducing animals. However, some simultaneous hermaphrodites - animals who have both male and female sex organs at the same time - have developed an escape route for this scenario7: self-fertilization. It is an imperfect solution, as any offspring produced by so-called "selfing" are bound to be inbred, but still better than not reproducing at all.
 
In previous studies, it had been established that the flatworm species Macrostomum hystrix is capable of switching to just such selfing behavior when isolated8 from mating partners, a behavior found in many but not all simultaneous hermaphrodites. In their new study, Dr. Lukas Schärer from the University of Basel and his team now show the bizarre, yet remarkable9 mechanisms10 Macrostomum hystrix has developed that make this possible.


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1 dent Bmcz9     
n.凹痕,凹坑;初步进展
参考例句:
  • I don't know how it came about but I've got a dent in the rear of my car.我不知道是怎么回事,但我的汽车后部有了一个凹痕。
  • That dent is not big enough to be worth hammering out.那个凹陷不大,用不着把它锤平。
2 prospects fkVzpY     
n.希望,前途(恒为复数)
参考例句:
  • There is a mood of pessimism in the company about future job prospects. 公司中有一种对工作前景悲观的情绪。
  • They are less sanguine about the company's long-term prospects. 他们对公司的远景不那么乐观。
3 zoologists f4b4b0086bc1410e2fe80f76b127c27e     
动物学家( zoologist的名词复数 )
参考例句:
  • Zoologists refer barnacles to Crustanceans. 动物学家把螺蛳归入甲壳类。
  • It is now a source of growing interest for chemists and zoologists as well. 它现在也是化学家和动物学家愈感兴趣的一个所在。
4 apparently tMmyQ     
adv.显然地;表面上,似乎
参考例句:
  • An apparently blind alley leads suddenly into an open space.山穷水尽,豁然开朗。
  • He was apparently much surprised at the news.他对那个消息显然感到十分惊异。
5 sperm jFOzO     
n.精子,精液
参考例句:
  • Only one sperm fertilises an egg.只有一个精子使卵子受精。
  • In human reproduction,one female egg is usually fertilized by one sperm.在人体生殖过程中,一个精子使一个卵子受精。
6 proceedings Wk2zvX     
n.进程,过程,议程;诉讼(程序);公报
参考例句:
  • He was released on bail pending committal proceedings. 他交保获释正在候审。
  • to initiate legal proceedings against sb 对某人提起诉讼
7 scenario lZoxm     
n.剧本,脚本;概要
参考例句:
  • But the birth scenario is not completely accurate.然而分娩脚本并非完全准确的。
  • This is a totally different scenario.这是完全不同的剧本。
8 isolated bqmzTd     
adj.与世隔绝的
参考例句:
  • His bad behaviour was just an isolated incident. 他的不良行为只是个别事件。
  • Patients with the disease should be isolated. 这种病的患者应予以隔离。
9 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。
10 mechanisms d0db71d70348ef1c49f05f59097917b8     
n.机械( mechanism的名词复数 );机械装置;[生物学] 机制;机械作用
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。 来自《简明英汉词典》
  • He explained how the two mechanisms worked. 他解释这两台机械装置是如何工作的。 来自《简明英汉词典》
TAG标签: species flatworm mating
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