经济学人精读 The Economist [41]
选自December 232017 Science and Technology 科技版块
更多英语阅读听力口语内容，请关注
微信公众号MyEnglishTrip
我是Eva💭
一个认真学英语的美少女😘
Evolutionary biology[进化的生物]
Hard to swallow[难以吞咽]
#Eva💭说#
在自然界，明亮鲜艳的颜色是有毒的警告。但是，最近一个实验证明了，不是所有的有色信号都是有毒的警告，虽然这一想法早在150年前就被人曾提出，但至今才得以验证。实验对象是象鼻虫，实验结果显示，这些颜色艳丽的象鼻虫并不是有毒的警告，而是它们坚硬外壳的警告。它们坚硬的外壳使捕食者难以将它们下咽。同时，研究人员还发现了，幼年象鼻虫，虽然还没有长出坚硬的外壳，但是它们会模仿成年象鼻虫的颜色，发出自己也有坚硬外壳的假信号。
#以上，个人总结和理解，欢迎批评指正，欢迎留言讨论#
#有输出才有进步#
Not all warning colouration signals toxicity[不是所有有色信号都是有毒的警告]
Bright colours in the natural world are often a warning[在自然界明亮的颜色通常都是一个警告]. In the case of tiger snakes, blue-ringed octopuses, arrow-poison frogs, hornets and many other species, the warning is that the animal carries toxins that will sicken or kill[像虎蛇，蓝环章鱼，箭毒蛙，大黄蜂和许多其他物种，它们的警告是这些有毒的动物将会生病或者死掉]. Thus it was that Alfred Russel Wallace, co-inventor of the theory of natural selection and an avid[热衷的]insect collector, proposed that the beautifully colouredPachyrhynchus[鞘翅目] weevils[象鼻虫] of eastern Asia and Australia were dangerous[因此，ARW，自然选择理论的共同提出者，也是一个狂热的昆虫收集者，提出东亚和澳大利亚色彩斑澜的鞘翅目象鼻虫是危险的].
Yet, after spending hours trying to pin the weevils onto wooden boards in his collection and eventually having to use a drill[钻孔机] for the chore[家庭杂物], he suggested that the threat the beetles were warning of with their colours was not poison, but the presence of body armour[铠甲]that would be impossible for predators to chew[但是，在他花了好长时间试图将象鼻虫钉在他的收集木板上，最终不得不使用做杂物使用的钻孔机之后，他认为这些甲壳虫颜色所警告的威胁不是有毒，而是，它们身体的铠甲是让捕食者无法嚼碎的]. Now, 150 years after Wallace proposed this idea, Chung-Ping Lin and Lu-Yi Wang of the NationalTaiwan Normal University, in Taipei, have tested it[现在，在W提出这个想法的150年后，来自台北国立台湾师范大学Lin和Wang，测试了这个想法]. They show, in a paper in theJournal of Experimental Biology, that Wallace was right[他们在实验生物学期刊中发表的论文显示，W是正确].
Dr Lin knew of Wallace’sidea and was surprised, when he conducted a literature review, to discover that it had never been testedformally[当Dr Lin做文献综述是，了解到了W的想法，并且意外的发现这个想法一直没有被正式检验]. He and Ms Wangtherefore collected from the wild sixPachyrhynchus weevils and 78 specimens of an insectivorous[食虫的] lizard called Swinhoe’s japalure[因此，他和Wang收集了6只野生P属象鼻虫和78只叫做Sj的食虫蜥蜴样本]. They then ran an experiment[之后他们便做了一次实验]. They used the weevils to found a breeding colony[他们利用这些象鼻虫找到了一个培育基地]. The lizards came from a place uninhabited[无人居住的] byPachyrhynchus weevils, so that the reptiles could have had no prior experience of such beetles[这些蜥蜴是来自没有P属象鼻虫的地方，因此这种爬行动物对这种甲壳虫没有以前的经验].
Each lizard was kept without food in a plastic cage for three days[每一只蜥蜴都被放在一个塑料笼子里禁食三天]. It was then presented with a weevil[之后，将象鼻虫放在它们面前]. The lizard had three minutes to attempt to eat the beetle before it was taken away again[这些蜥蜴在这些象鼻虫被拿走之前，有三分钟的时间尝试吃掉它们]. In some cases the weevils were two months old, an age at which their armoured exoskeleton is fully developed and hardened[其中有一些象鼻虫2个月大，它们的外壳的外骨骼已经完全发育并变得坚硬]. In others, they were newly hatched[孵出，出壳] from theirpupae[蛹] and their exoskeletons were still soft[另一些象鼻虫，是刚刚破蛹而出，他们的外骨骼仍旧是软的]. A spectroscopic[分光镜的] analysis showed, however, that all were precisely the same hue[色彩][然而，分光镜分析显示，他们全部有着完全一样的色彩].
Half of the lizards attacked the weevil soon after it was introduced into the arena[竞技场，舞台][有一半的蜥蜴在象鼻虫被放进去不久就袭击的它们].Those that attacked a two-month-old took only one bite before spitting the insect out[那些袭击了2个月大象鼻虫的蜥蜴在只咬了一口以后就将它们吐了出来]. All weevils so rejected survived the encounter and went on to live out the remaining two months of their lives in the comfort of Dr Lin’s laboratory[那些被冷落而存活下来象鼻虫（指被蜥蜴吐出）继续在Dr Lin舒适的实验室中度过了剩余的两个月的生命]. In contrast, all of the newly hatched beetles that were attacked were crushed by the lizards’ jaws and eaten[相比之下，所有那些被袭击的刚刚孵出的甲壳虫，被蜥蜴咬碎并吃掉了]. That showed the weevils did not taste noxious[这说明这些象鼻虫是没有毒的]. Nor did any of the beetle-consuming lizards show any subsequent signs of having beenpoisoned[那些吃了象鼻虫的蜥蜴也没有表现出任何中毒后的症状].
These findings suggested that the tough[坚硬的] carapace[甲壳] was the defensive mechanism that the weevils were warning of with their colours[这些结果说明，坚硬的甲壳是象鼻虫用它们的颜色警告的防御武器]. However, the researchers theorised that the claws the insects have at the ends of their legs, which sharpenas their body armour hardens, might also force lizards to spit them out[然而，研究人员提出了这样的理论，这些昆虫腿末端的爪子，随着它们身体甲壳的变硬也变得锋利，也可能使蜥蜴将它们吐出]. To check, they offered lizards weevils that had had their claws removed[为检测这一理论，它们给蜥蜴提供了去掉了爪子的象鼻虫]. It made nodifference[结果没有不同]. If the weevil was a two-month-old, it got spat out[如果象鼻虫两个月大，它就被吐出来]. If it was a juvenile, it was devoured[吞食][如果是刚孵化出的象鼻虫，就被吞食].
Dr Lin and Ms Wang did also consider the possibility that mature weevils, unlike newly hatched ones, might contain or be coated by a toxic or noxious compound[Lin和Wang也同样考虑这样的可能性，成年的象鼻虫，不像那些刚孵化出来的，可能含有或是在外壳中含有有毒或有害成分]. To find out, they ground[grind过去式，磨碎] some up and analysed the compounds there in using mass spectrometry[质谱法] and gas chromatography[气相色谱法][为了一探究竟，它们磨碎了一些象鼻虫，并用质谱法和气相色谱法分析成分]. This revealed nothing known to be poisonous or irritating[刺激性的][结果显示没有一种是有毒或刺激的成分].
Theupsum[小编没有查到这个单词的意思，猜测为“综上”实验结果], then, is that Wallace seems to have beencorrect[综上实验结果显示，W的想法是正确的]. But the story does not end there[但是，这并不是故事的结束]. Since both edible[可以吃的] and inediblePachyrhynchus sport the same warning patterns, the newly hatched, soft-bodied beetles are actually sailing under false colours[既然可食用和不可食用的鞘翅目被发现了相同的警告模式，那么新孵化出的和软壳的甲壳虫事实上在用错误颜色]. They are, in essence, mimicking their elders[事实上，它们在模仿那些成年甲壳虫]. Mimicry of a dangerous animal by a harmless one is a well-knownphenomenon[无害的动物模仿那些危险的动物是一种广为人知的现象]. But this is the first known case in natural history where a harmless animal benefits from mimicking its future self[但是，这是自然历史中，第一个被发现的，无害的动物受益于模仿未来的自己].
20171230 689 words
更多英语阅读听力口语内容，请关注
微信公众号MyEnglishTrip
我是Eva💭
一个认真学英语的美少女😘
网友评论