雅思真题听力场景精练 第124期:模拟试卷(四) Section8
日期:2013-10-24 08:30

(单词翻译:单击)

Other organisms defend themselves directly with stings or bites,or with poisons or other noxious chemicals,and such organisms often assume bold,characteristic colors and markings-called warning coloration-that warns a predator,reminds it,that this creature can inflict pain or discomfort,or that it tastes very bad. The bold orange-and-black pattern of the common Monarch Butterfly is such warning colorations.
And sometimes,this warning coloration is so effective that another species,a species that doesn't have any of the protective devices of sting or poison or whatever,will adopt the same warning colors and pattern.This sort of mimicry is called "Batesian mimicry".The name comes from the early zoologist,HW Bates,who,back in 1862,first suggested an explanation for the origins of mimicry based on Charles Darwin's ideas to an unknown biological phenomenon.Now,Viceroy Butterflies taste good to many birds,but because they mimic the Monarch Butterflies model's color pattern,because Viceroy Butterflies look like Monarch Butterflies,they are avoided,just like the Monarch is.In the same way,many harmless fly species resemble the bumblebee model,and also in this way they avoid being eaten by the recipients,birds.So these are Batesian mimics.there are several conditions that must be fulfilled,though,for a Batesian mimic to be successful-the mimic must of course share the same general region and habitat as its model,but the mimic must also be less numerous than its model,which must be relatively abundant.That way,the odds are that the recipient predator will sample an unpalatable model first,which is very important for keeping the trick effective.

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重点单词
  • poisonn. 毒药,败坏道德之事,毒害 vt. 毒害,摧毁,中毒
  • mimicadj. 模仿的,假的 [计算机] 模拟的 vt. 模仿
  • unpalatableadj. 不适口的,不好吃的,让人不快的
  • inflictvt. 施以,加害,使遭受,折磨
  • resemblevt. 相似,类似,像
  • monarchn. 帝王,统治者,元首/nn. 君王斑点蝶
  • avoidvt. 避免,逃避
  • habitatn. (动植物的)产地,栖息地
  • characteristicadj. 特有的,典型的 n. 特性,特征,特色
  • effectiveadj. 有效的,有影响的