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HeleneMorlon_EnvironmentalDNA_2021E-_dna_能否告诉我们一切？_
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| For years, scientists have been staking out this remote forest in Montana for an animal that’s notoriously tricky to find. |
多年以来,科学家们一直致力于 在蒙大拿州的这片偏僻的森林里 追踪一种难以寻觅的动物。 |
| Camera traps haven’t offered definitive evidence , and even experts can't identify its tracks with certainty . |
红外相机的拍摄并不能提供确切的证据。 甚至连相关专家也无法确定它的踪迹。 |
| But within the past decades, researchers have developed methods that can detect even the most elusive species . |
然而在过去的几十年里, 研究者们已经开发出了 许多监测那些最为神出鬼没的物种的方法。 |
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staking:v.(就某事)以…打赌,拿…冒险;用桩支撑;(stake的现在分词) remote:adj.偏远的;偏僻的;遥远的;久远的; Montana:n.蒙大纳(美国州名); notoriously:adv.众所周知地;声名狼藉地;恶名昭彰地; tricky:adj.难办的;难对付的;狡猾的;诡计多端的; traps:n.陷阱,捕捉器; v.使落入险境; (trap的第三人称单数和复数) definitive:n.限定词;adj.决定性的;最后的;限定的; evidence:n.证据,证明;迹象;明显;v.证明; identify:v.识别:鉴定:确认:发现: tracks:n.小道;足迹;车辙;轨道;v.追踪;跟踪;(track的第三人称单数和复数) certainty:n.必然;确实;确实的事情; detect:vt.察觉;发现;探测; elusive:adj.难懂的;易忘的;逃避的;难捉摸的; species:n.[生物]物种;种类;
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| And so, in 2018, these scientists took a sample from some conspicuous snow tracks. |
因此在 2018 年,这些科学家们从那些 显而易见的雪地足迹中提取了相关样本。 |
| Lab tests showed conclusive results: the Canada lynx was indeed present in the area. |
检测的结果确切地表明: 加拿大猞猁的确曾在这片区域内活动。 |
| Without seeing the cat, scientists had proof it was there because of environmental DNA or eDNA. |
在没有肉眼观测到其出现的情况下, 科学家们仍能断定它的存在, 归功于环境 DNA,也就是 eDNA。 |
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conspicuous:adj.显著的;显而易见的; conclusive:adj.决定性的;最后的;确实的;确定性的; lynx:n.猞猁;山猫; proof:n.证据;证实;adj.能抵御;可防护;
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| Using a technique called DNA metabarcoding, researchers can take a sample from the environment and learn which organisms are in it or have recently passed through it. |
通过使用 DNA 复合条形码这技术, 研究者们可以通过检测从环境中所收集到的样本, 进而得知该样本中包含哪些物种 或是近期哪些物种经过此地。 |
| The world is covered in DNA. |
世界上遍布着 DNA。 |
| on the ground, at the bottom of the ocean, and up in the clouds . |
在陆地上,深海里,还是云霄之上,都存在。 |
| Multicellular organisms are constantly shedding cells. |
多细胞生物的细胞不断地脱落。 |
| But until recently, eDNA wasn’t very useful to us. |
但是环境 DNA 直到最近方为我们所用。[01:14] |
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technique:n.技巧,技术;手法; organisms:n.[生物]生物体(organism的复数);[生物]有机体; recently:adv.最近;新近; in the clouds:心不在焉;在云层中; Multicellular:adj.[生物]多细胞的;多空隙的; constantly:adv.不断地;时常地; shedding:v.去除;摆脱;使落下;掉落(货物);(shed的现在分词)
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| Traditional scientific techniques couldn’t parse environmental samples containing mixed genetic material from multiple species. |
传统的技术无法解析环境的样本, 如果样本混合了多种生物的遗传物质。 |
| But DNA metabarcoding can. |
幸运的是,“DNA 复合条形码” 可以帮我们解决这个难题。 |
| DNA begins to degrade once it’s exposed to the environment. |
一旦暴露在环境中,DNA 会自行开始降解。 |
| In the ocean, for example, it may only persist for a few days. |
例如,在海洋中,只需几天时间就降解了。 |
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Traditional:传统的,惯例的, scientific:adj.科学的,系统的; techniques:n.技巧;技艺;工艺;技术;(technique的复数) parse:vt.解析;从语法上分析;vi.理解;从语法上分析;n.从语法上分析;分列; genetic:adj.基因的;遗传学的; multiple:adj.数量多的;多种多样的;n.倍数; degrade:v.降低…身份;使受屈辱;(使)退化,降解;分解;降低; exposed:adj.无遮蔽的; v.暴露; (expose的过去分词和过去式) persist:v.保持;持续存在;维持;顽强地坚持;
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| So in many contexts , eDNA is useful for telling us about the recent past. |
因此,在多数情况下,环境 DNA 对我们了解近期活动起到十分重要的作用。 |
| The process of DNA metabarcoding starts with an environmental sample like a core of soil, a vial of water, some feces , an insect trap, or even the blood from leeches’ stomachs. |
在使用 DNA 复合条形码之前, 我们需要收集相关环境样本。 像是一份核心土壤,一小瓶水, 一些排泄物,一个捕虫器, 甚至是来自水蛭胃里的血液 都能作为很好的样本。 |
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contexts:n.环境,[计]上下文(context复数); process:v.处理;加工;列队行进;n.过程,进行;方法,adj.经过特殊加工(或处理)的; core:n.核心;要点;果心;[计]磁心;vt.挖...的核; vial:n.(用于盛装香水、药物等的)小瓶; feces:n.排泄物;渣滓;
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| Researchers then sift out everything aside from DNA by blending the sample up and using enzymes that break down cellular proteins and release DNA, which they purify . |
研究者接着混合样本, 排除里头不是 DNA 的物质。 用酶分解细胞中的蛋白质释出 DNA, 将其纯化。 |
| The result is a “soup” of all the DNA in the sample. |
最终得到一份包含所有 DNA 样本的 “汤”。 |
| Scientists then apply the polymerase chain reaction or PCR, which uses artificial DNA strands called universal primers . |
接着科学家们应用聚合酶链式反应,简称 PCR, 使用一种被称为通用引物的人工合成 DNA 链。 |
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sift:vt.筛选;撒;过滤;详查;vi.筛;详查;撒下;细究; blending:v.使混合;掺和;混合;融合;(使)调和,协调(blend的现在分词) enzymes:n.[生化]酶(enzyme的复数);酶类,酵素; proteins:n.[生化]蛋白质(protein复数); release:v.释放;发射;让与;允许发表;n.释放;发布;让与; purify:v.使(某物)洁净;净化(心灵);提纯;精炼; apply:v.申请;涂,敷;应用;适用;请求; polymerase:n.[生化]聚合酶; chain reaction:连锁反应; artificial:adj.人造的;仿造的;虚伪的;非原产地的;武断的; strands:n.线; v.搁浅; universal:adj.普遍的;全体的;全世界的;共同的; primers:n.[生化]引物;[生化]引子;引信;启蒙书(primer的复数形式);
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| These primers bind to DNA sequences that are similar across species, then amplify genetic barcodes that are species-specific. |
这些引物会结合不同物种间相似的 DNA 序列, 然后扩增出具有物种特异性的基因条形码。 |
| High-throughput sequencing then reads millions of these DNA fragments , simultaneously . |
高通量测序随即读取 数以百万计 DNA 片段的信息, 并行运作。 |
| And finally , researchers compare them to reference databases and identify how many and which species are present— or if they’ve found entirely new ones. |
最后,研究者们会将这些信息 与参考数据库中的数据进行比较, 辨识出有多少已知的存在物种, 抑或发现了全新的物种。 |
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bind:v.结合;装订;有约束力;过紧;n.捆绑;困境;讨厌的事情;植物的藤蔓; sequences:n.[数][计]序列,顺序;继起的事(sequence的复数形式); amplify:vt.放大,扩大;增强;详述;vi.详述; barcodes:n.条形码;条码技术; High-throughput:高通量; sequencing:n.[计]排序; v.[计]定序(sequence的ing形式); fragments:n.碎片(fragment的复数);片断;[计]分段;v.破碎(fragment的三单形式);打碎; simultaneously:adv.同时地; finally:adv.终于;最终;(用于列举)最后;彻底地; compare:v.比较;对比;n.比较; reference:n.参考,提及;参考书目;证明书;v.引用;
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| This method has led to the discovery of tens of thousands of species over the past decade. |
这个方法已帮助我们发现了数以万计的物种, 在过去的十几年中。 |
| While metabarcoding can detect elusive animals like the Canada lynx, it can also help scientists identify invasive species. |
DNA 复合条形码不仅可以帮助科学家 监测像加拿大猞猁这样行踪不定的动物, 也帮助科学家识别那些入侵的物种。 |
| In Yosemite , researchers used eDNA to track and remove invasive bullfrogs . |
在优胜美地国家公园,研究者用环境 DNA 来追踪和清除入侵的牛蛙物种。 |
| Once no trace of these amphibians remained, they reintroduced a threatened native species, California red-legged frogs, which had disappeared from the area some 50 years prior . |
一旦这些两栖动物的踪迹不复存在, 他们重新引入一种已濒临绝种的 本地物种,加州红腿蛙。 该物种在大约 50 年前从该地区消失了。 |
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invasive:adj.侵略性的;攻击性的; Yosemite:n.约塞米蒂国家公园(位于美国加利福尼亚州中部); bullfrogs:n.[脊椎]牛蛙;菜蛙; trace:追溯,追踪 amphibians:n.两栖动物;[古生]两栖类; reintroduced:vt.再引入;再提出;再介绍; native:adj.本国的;土著的;天然的;与生俱来的;天赋的;n.本地人;土产;当地居民; disappeared:adj.消失的;消失了的;v.消失,失踪;(disappear的过去式和过去分词) prior:adj.先前的; n.(小隐修院)院长; v.居先;
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| Likewise , DNA metabarcoding can be used to monitor biodiversity . |
同样地,DNA 复合条形码 还能用于监测生物多样性。 |
| For example, using traditional approaches , categorizing all of the insects in a hectare of rainforest can take decades. |
例如,若是使用传统的方法 来对一公顷左右雨林中的所有物种分类, 可能会需要耗费长达数十年的时间。 |
| But DNA from insect traps could yield these results in just a few months. |
但是用来自昆虫诱捕器的 DNA 仅需几个月就可以收获结果。 |
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Likewise:adv.同样地;也; biodiversity:n.生物多样性; approaches:v.靠近,接近; n.方式,方法,态度; categorizing:n.分类;分类题;v.分类(categorize的ing形式); hectare:n.公顷(等于1万平方米); rainforest:n.(热带)雨林; yield:n.产量;产出;利润;v.屈服;让步;放弃;提供;
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| One study compared insects from adjacent forest and plantation sites within China’s Yunnan province. |
目前,已有一项研究比较邻近森林 和种植园内昆虫物种的不同, 地点在中国云南省内。 |
| It quickly found that not only were plantations less diverse , but deforestation affected insect groups unequally . |
研究很快发现,不仅种植园内的多样性较差, 而且毁林对不同的昆虫种群有着不同的影响。 |
| Grasshoppers thrived in cleared areas while specialist forest beetles declined . |
蚱蜢可以在清理过的区域内茁壮成长, 而森林甲虫的数量却在逐渐下降。 |
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compared:adj.比较的,对照的; v.相比; (compare的过去式和过去分词) adjacent:adj.邻近的,毗连的; plantation:n.种植园;木材林地;人造林; sites:n.网站(site的复数);遗址,举办地点;v.使...位于(site的单三形式); plantations:n.[农]种植园(plantation的复数形式); diverse:adj.不同的;多种多样的;变化多的; deforestation:n.采伐森林;森林开伐; unequally:adv.不相等地;不均匀地;不公平地; Grasshoppers:n.草蜢; v.像蚱蜢似地跳; thrived:v.兴盛,繁荣(thrive的过去式和过去分词形式); beetles:n.甲虫;v.快速移动;(beetle的第三人称单数和复数) declined:v.减少;下降;衰弱;婉言拒绝;(decline的过去分词和过去式)
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| Using eDNA, scientists are able to investigate complex ecosystem interactions . |
通过使用环境 DNA,科学家们能够调查 复杂的生态系统之间的相互作用。 |
| Tracking thousands of insects as they visit flowers is impossible. |
想要追踪数以千计接近花朵的昆虫几乎不可能。 |
| Instead, researchers can study the DNA left on flowers and insects to map pollination networks. |
取而代之,研究者可以通过检测 留在花和昆虫身上的 DNA, 进而绘制它们授粉的网络图。 |
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investigate:v.调查;研究;审查; complex:adj.复杂的;合成的;n.复合体;综合设施; ecosystem:n.生态系统; interactions:n.[计]交互,相互作用;相互交流;干扰;(interaction复数) Tracking:n.追踪,跟踪;v.跟踪;(track的现在分词) pollination:n.[农学]授粉(作用);
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| Before these techniques were available, we didn’t really know how much pollination was happening at night because we couldn’t observe it. |
未有这些技术之前,我们并不清楚 有多少夜间授粉活动, 因为我们无法直接观察。 |
| Now scientists understand that moths are important nocturnal pollinators . |
如今科学家已能确定飞蛾种群 是十分重要的夜间传粉者。 |
| eDNA can even tell stories of long extinct species. |
环境 DNA 甚至可以告诉我们 关于那些早已灭绝的物种的故事。 |
| Cold, dry, and low oxygen conditions are perfect for preserving genetic material, |
寒冷,干燥和低氧的环境 是保存遗传物质的完美条件。 |
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observe:v.观察;看到;庆祝;监视; moths:n.飞蛾,蛾(moth的复数); nocturnal:adj.夜的;夜曲的;夜间发生的; pollinators:n.[植][农学]传粉者(pollinator的复数); extinct:adj.灭绝的,绝种的;熄灭的;vt.使熄灭; preserving:n.保留,保存;
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| By digging deep into the Arctic permafrost , researchers found 50,000 year old DNA, which they matched to the nutrient-rich plants found in the stomachs of woolly mammoths . |
通过深入挖掘北极的永久冻土层, 研究人员发现了大约 5 万年前的 DNA 物质, 发现其与具有极高营养价值的植物匹配, 是在长毛象胃中发现的（植物）。 |
| With eDNA, they also found that less nutritious grasses colonized the Arctic steppe during the last ice age, potentially contributing to the mammoth decline. |
通过环境 DNA,研究者还发现那些缺乏营养价值的草 在最后一个冰河时期内于北极草原上肆意生长, 极可能加速了长毛象种群数量的减少。 |
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Arctic:adj.北极的;北极地区的;极冷的;严寒的;n.北极;北极地区; permafrost:n.永久冻土,永久冻地;永久冻结带;永久冰冻; nutrient-rich:营养的; woolly:adj.羊毛的;模糊的;似羊毛的;n.羊;毛织衣服; mammoths:n.长毛象;猛犸象;庞然大物;adj.巨大的,庞大的;猛犸似的; nutritious:adj.有营养的,滋养的; colonized:vt.将…开拓为殖民地; vi.开拓殖民地; steppe:n.大草原,[地理]干草原(特指西伯利亚一带没有树木的大草原); potentially:adv.可能地,潜在地; contributing:v.捐献,捐赠(尤指款或物);捐助;增加;增进;(contribute的现在分词)
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| As we face another period of climate change— this time due to human activities— understanding our planet’s rapidly shifting biodiversity will be crucial to protecting it. |
鉴于我们正处于另一个气候变化的阶段, 而这一次却是由于人类活动所造成, 了解我们地球生物多样性正快速改变 将会是后续保护它的关键。 |
| Fortunately , eDNA and metabarcoding give us the tools to document rapid change in real time . |
值得庆幸的是,环境 DNA 和 DNA 复合条形码 赋予了我们实时记录变幻莫测的生物多样性的能力。 |
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shifting:adj.不断移动的;流动的;v.转移;赶快;快速移动;变换;(shift的现在分词) crucial:adj.重要的;决定性的;定局的;决断的; Fortunately:adv.幸运地; real time:adj.实时的;接到指示立即执行的;
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