Snake poison

原文

How it came about that snakes manufactured poison is a mystery. Over the periods their saliva, a mild, digestive juice like our own, was converted into a poison that defies analysis even today. It was not forced upon them by the survival competition; they could have caught and lived on prey without using poison, just as the thousands of non-poisonous snakes still do. Poison to a snake is merely a luxury; it enables it to get its food with very little effort, no more effort than one bite. And why only snakes? Cats, for instance, would be greatly helped; no running fights with large, fierce rats or tussles with grown rabbits -- just a bite and no more effort needed. In fact, it would be an assistance to all carnivores though it would be a two-edged weapon when they fought each other. But, of the vertebrates, unpredictable Nature selected only snakes (and one lizard). One wonders saliva into why Nature, with respect from that of others, as other on the blood.

In the conversion of saliva into poison, one might suppose that a fixed process took place. It did not; some snakes manufacture a poison different in every respect from that of others, as different as arsenic is from strychnine, and having different effects. One poison acts on the nerves, the other on the blood.

The makers of the nerve poison include the mambas and the cobras and their venom is called neurotoxic. Vipers (adders) and rattlesnakes manufacture the blood poison, which is known as haemolytic. Both poisons are unpleasant, but by far the more unpleasant is the blood poison. It is said that the nerve poison is the more primitive of the two, that the blood poison is, so to speak, a newer product from an improved formula. Be that as it may, the nerve poison does its business with man far more quickly than the blood poison. This, however, means nothing. Snakes did not acquire their poison for use against man but for use against prey such as rats and mice, and the effects on these of viperine poison is almost immediate.

--JOHN CROMPTON The snake--

译文

蛇产生毒液的过程是一个谜。 在漫长的岁月里,它们那类似于我们自己的温和消化液——唾液,转化成了至今难以分析的毒液。这并非生存竞争所迫使;它们本可以不靠毒液捕获并食用猎物,正如成千上万的无毒蛇至今仍那样做。对于蛇来说,毒液不过是一种奢侈;它让它们只需轻轻一咬,便能毫不费力地获取食物。为什么只有蛇呢?例如,猫若有毒液,将大有助益;不再需要与凶猛的大鼠展开追逐,或与成年兔子纠缠——只需一咬,一切就结束了。事实上,这对所有肉食动物都是一种帮助,尽管在它们相互搏斗时,这武器将是双刃的。然而,在脊椎动物中,难以预料的大自然只选择了蛇(以及一种蜥蜴)。人们不禁要问,为什么大自然会让蛇的唾液转化为毒液,与其他动物的不同,有的针对神经,有的针对血液。

在唾液转化为毒液的过程中,人们或许会以为有一个固定的过程。其实不然;有些蛇制造的毒液在各方面都与别种蛇的迥然不同,就如砒霜与马钱子碱的差异一般,而且效果各异。其中一种毒液作用于神经,另一种则作用于血液。

制造神经毒液的蛇包括曼巴蛇和眼镜蛇,它们的毒液被称为神经毒性毒液。毒蛇(蝰蛇)和响尾蛇则产生血液毒液,也称溶血性毒液。这两种毒液都令人不快,但远为难受的还是血液毒液。据说,神经毒液是两者中较为原始的一种,血液毒液则可说是从改良配方中产生的新产品。不管怎样,神经毒液对人作用得远比血液毒液迅速。然而,这并不意味着什么。蛇获得毒液并非为了对付人类,而是为了捕猎如鼠类和鼠目动物这样的猎物,而蝰蛇毒液对这些猎物的效果几乎是即时的。

--JOHN CROMPTON The snake--

词汇表

mystery

名词
英:/ˈmɪst(ə)ri/
美:/ˈmɪstəri/
定义
1. 谜团 - Something that is difficult or impossible to understand or explain.

例子: The origin of the universe remains a mystery to scientists.

例子: How the ancient Egyptians built the pyramids is still a mystery.

近义词
enigma: 更强调复杂且难以解决的问题,常用于智力谜题,而 'mystery' 更泛指未知事件。
puzzle: 更口语化,常指需要解决的难题,'mystery' 则带有更深的未知感。
riddle: 通常暗示一个谜语或问题需要解答,'mystery' 更侧重于自然或事件的不可解性。
反义词:
solution, explanation, clarity
用法
常用于描述未知现象或事件,常出现在科学、侦探或哲学语境中;如 'mystery novel' 表示侦探小说。
形式:
复数: mysteries

关键句型 "as [adjective] as A is from B"

定义

此句型用于表达两个事物之间的显著差异或比较,强调一种强烈的对比关系。结构为:as + [adjective](形容词)+ as + [A is from B],其中 A 和 B 是名词或名词短语,表示两个实体间的区别。根据《剑桥英语语法手册》,这种句型是英语中高级比较结构的变体,常用于描述程度或本质上的差异,类似于 "as...as" 的扩展形式,但更侧重于分离或对比。

例如,在文章中,“as different as arsenic is from strychnine” 清晰地展示了这种用法,突出两种毒素的根本不同。

用法

此句型主要用于正式写作或描述性语言中,强调事物的独特性或对比强度。规则:它通常出现在主句前或作为从句,as [adjective] 后跟 as [A is from B],其中 [A is from B] 提供具体对比点。

在语法体系中,此句型属于比较结构家族,与基本 "as...as"(表示相等)相关,但更进阶,因为它引入了分离的概念。横向比较:与 "as...as"(如 "as tall as",表示相等高度)相比,此句型强调差异,而非相似;与 "more...than"(如 "more dangerous than")相比,它更诗意和正式,常用于文学或科学描述,而 "more...than" 更直接。

跨语法联系:它常与形容词和名词短语结合,还可链接到其他比较工具,如 "like" 或 "unlike",帮助学生构建更复杂的句子。例如,学生可以扩展到 "not as [adjective] as" 以表示不如。

此句型在文章如 "as different as arsenic is from strychnine" 中增强了表达的精确性,适合科学或解释性文本。

注意事项

学生易犯的错误包括:错误放置 "as",导致句子混乱(如说 "as arsenic is different from strychnine",改变了结构);或使用不恰当的形容词,使对比不成立。纠正建议:始终确保 [adjective] 准确描述差异,并提供具体例子以强化。另一个常见偏误是遗漏 "is from" 部分,使句子不完整(如 "as different as arsenic from strychnine"),这会让表达显得草率。

错误示例:The two poisons are as toxic as each other is from.
正确示例:The two poisons are as different as arsenic is from strychnine.

在口语中,学生可能简化过度,失去正式感;练习时,强调保持完整结构。

练习

原创例子:假设在讨论动物特征时,你可以说:“The behavior of wolves is as aggressive as a lion is from a deer.” 这句强调狼的攻击性和狮子与鹿的差异。学生可以替换关键词,如将 [adjective] 改为 "unique",并调整 A 和 B,例如:“The taste of this fruit is as sweet as honey is from vinegar.” 这样,学生能在日常对话中应用,例如在品尝食物时说:“This coffee is as strong as espresso is from tea.”

通过替换练习,学生能加深对句型的灵活性,逐步从简单对比过渡到复杂描述。

额外内容

背景知识:这种句型源于英语的拉丁语影响,常在19世纪文学中出现,如达尔文的作品,用于进化论讨论。文化对比:与中文的 "像A一样不同于B" 类似,但英语更结构化。相比法语的 "aussi différent que A est de B",英语版本更简洁,有助于初学者。学习此句型能丰富学生的表达,帮助他们在科学文章中自信使用,同时对比其他语言的结构(如日语的比喻表达),加深对英语独特性理解。

关键句型 "It would be [adjective/noun phrase]"

定义

此句型用于表达假设、建议或潜在结果,结构为:It + would be + [adjective/noun phrase],表示某种情况的可能性或益处。根据《牛津现代英语语法》,这是一种情态动词句型,常用于礼貌或假设语境,would be 软化语气,强调条件性结果。

在文章中,如 "Cats, for instance, would be greatly helped",它展示了毒液对动物的潜在优势。

用法

此句型常用于讨论假设场景、建议或推测未来,常在非正式到正式的语境中出现。规则:It 作为形式主语,would be 表示条件或虚拟,[adjective/noun phrase] 提供描述,如 "greatly helped" 或 "an assistance"。

在语法体系中,它属于情态动词结构,与条件句相关。横向比较:与 "It is [adjective]"(直接陈述)相比,would be 更委婉,适合表达不确定性;与 "It could be" 相比,would be 暗示更可能的假设,而 "could be" 强调可能性。跨语法联系:它可与条件从句结合,如 "If cats had poison, it would be helpful",帮助学生连接到虚拟语气或假设句。

此句型在文章中增强了讨论的逻辑性,适合科学或推测性写作。

注意事项

学生常犯错误是混淆 wouldwill,如说 "It will be helpful",这会使语气更强硬而非假设。纠正建议:练习时,强调 would 用于虚拟或礼貌语境,并避免省略 be,如直接说 "It would helpful"(错误)。另一个偏误是使用不当的形容词短语,导致句子不自然。

错误示例:It would greatly help cats without any effort.
正确示例:It would be greatly helpful for cats without any effort.

口语中,学生可能忘记 "It",直接说 "Would be helpful",这会使句子不完整。

练习

原创例子:在日常对话中,你可以说:“If I had more time, it would be easier to learn a new language.” 学生可以替换 [adjective/noun phrase],如改为 "challenging",并调整语境,例如:“Buying that car would be a luxury for me.” 这能帮助他们在购物或规划时应用,如对朋友说:“Going on vacation now would be refreshing.”

替换练习鼓励学生探索不同场景,强化句型的实际使用。

额外内容

背景知识:would be 起源于古英语的条件表达,常见于现代英语的礼貌语言中。文化对比:与西班牙语的 "sería"(would be)类似,但英语更灵活。相比中文的 "会是",此句型通过结构体现假设性。学习它能帮助学生在辩论或写作中表达 nuanced 观点,同时对比其他语言(如德语的 Konjunktiv),提升跨文化理解。