原文已被隐藏，你可用 快捷键 - 或点击 显示原文 按钮来查看原文
第一段
1 .For my project on invertebrates, I chose to study tardigrades. These are microscopic – or to be more precise – near-microscopic animals.
在我的无脊椎动物项目中，我选择了研究缓步动物。它们是微型动物，或者更准确地说，是接近微型的动物。
2 .There are well over a thousand known species of these tiny animals, which belong to the phylum Tardigrada.
目前已知有1000余种，属于缓步动物门。
3 .Most tardigrades range in length from 0.05 to 1 millimetre, though the largest species can grow to be 1.2 millimetres in length.
大多数水熊虫的长度在 0.05 到 1 毫米之间，最大的种类可以长到 1.2 毫米。
4 .They are also sometimes called ‘water bears’: ‘water’ because that’s where they thrive best, and ‘bear’ because of the way they move.
它们有时也被称为 "水熊"："水 "是因为它们在水里生长得最好，而 "熊 "则是指它们移动的方式。
5 .‘Moss piglet’ is another name for tardigrades because of the way they look when viewed from the front.
“苔藓小猪”是缓步动物的另一个代称，这得名于它们正面的形态。
6 .They were first discovered in Germany in 1773 by Johann Goeze, who coined the name Tardigrada.
它们最早是由约翰·戈泽于 1773 年在德国发现的，戈泽创造了“缓步动物”这个名字。
7 .As I say, there are many different species of tardigrade – too many to describe here – but,generally speaking, the different species share similar physical traits.
正如我所说的那样，缓步动物有许多不同的种类-这里就不一一介绍了-但一般来说，不同种类的缓步动物都有相似的身体特征。
8 .They have a body which is short, and also rounded – a bit like a barrel – and the body comprises four segments.
它们身体很短，像圆圆的桶状物-其身体由四节组成。
9 .Each segment has a pair of legs, at the end of which are between four and eight sharp claws.
每节都有一对腿，腿的末端有四到八只锋利的爪子。
10 .I should also say that some species don’t have any claws; what they have are discs, and these work by means of suction. They enable the tardigrade to cling on to surfaces or to grip its prey. Within the body, there are no lungs, or any organs for breathing at all.
我还应该说，有些种类没有爪子；它们有的只是吸盘，这些吸盘通过吸力工作。它们能让缓步动物紧紧抓住物体表面，或者抓住猎物。在缓步动物体内，没有肺，也没有任何呼吸器官。
11 .Instead, oxygen and also blood are transported in a fluid that fills the cavity of the body.
相反，氧气和血液由充满在体腔内的液体运输的。
12 .As far as the tardigrade’s head is concerned, the best way I can describe this is that it looks rather strange – a bit squashed even，
就缓步动物的头部而言，我所能做的最好描述就是它看起来相当奇怪-甚至有点扁，
13 .though many of the websites I looked at described its appearance as cute, which isn’t exactly very scientific.
尽管我看过的许多网站都把它的外观描述为可爱，但这并不完全科学。
14 .The tardigrade’s mouth is a kind of tube that can open outwards to reveal teeth-like structures known as ‘stylets’.
缓步动物的嘴是一种管状结构，可以向外张开，露出被称为“管心针"的牙齿状结构。
15 .These are sharp enough to pierce plant or animal cells.
这些结构非常锋利，足以刺穿植物或动物细胞。
16 .So, where are tardigrades found?
那么，缓步动物是在哪里被发现的呢？
17 .Well, they live in every part of the world, in a variety of habitats: most commonly, on the bed of a lake, or on many kinds of plants or in very wet environments.
它们生活在世界各地的各种栖息地：最常见的是在湖床、多种植物或非常潮湿的环境中。
18 .There’s been some interesting research which has found that tardigrades are capable of surviving radiation and very high pressure,
一些有趣的研究发现，缓步动物能在辐射和高压下生存，
19 .and they’re also able to withstand temperatures as cold as –200 degrees centigrade, or highs of more than 148 degrees centigrade, which is incredibly hot.
它们还能抵御零下 200 摄氏度的低温或超过 148 摄氏度的极端高温。
第二段
1 .It has been said that tardigrades could survive long after human beings have been wiped out, even in the event of an asteroid hitting the earth.
据说，即使在小行星撞击地球的情况下，缓步动物也能在人类灭绝后长期存活。
2 .If conditions become too extreme and tardigrades are at risk of drying out, they enter a state called cryptobiosis.
如果条件变得过于极端，缓步动物面临失水风险，它们就会进入一种叫做隐生的状态。
3 .They curl into a ball, called a tun – that’s T-U-N – by retracting their head and legs, and their metabolism drops to less than one percent of normal levels.
它们把头和腿缩成一团，进入所谓的“tun”状态，新陈代谢下降到正常水平的百分之一以下。
4 .They can remain like this until they are re-introduced to water, when they will come back to life in a matter of a few hours.
它们会一直保持这种状态，直到重新接触到水，之后缓步动物便会在几小时内就恢复生机。
5 .While in a state of cryptobiosis, tardigrades produce a protein that protects their DNA.
在隐生状态下，缓步动物会产生一种保护其 DNA 的蛋白质。
6 .In 2016, scientists revived two tardigrades that had been tuns for more than 30 years.
2016 年，科学家复苏了两只已处于“tun”状态30 多年的缓步动物。
7 .There was a report that, in 1948, a 120-year-old tun was revived, but this experiment has never been repeated.
有报道称，1948 年，一只处于“tun”状态120年的缓步动物复苏了，但这一实验再未开展过。
8 .There are currently several tests taking place in space, to determine how long tardigrades might be able to survive there. I believe the record so far is 10 days.
目前正在太空中进行几项测试，以确定缓步动物能在太空中存活多长时间。我想目前的记录是 10 天。
9 .So, erm, moving on. In terms of their diet, tardigrades consume liquids in order to survive.
那么，我们继续。在饮食方面，缓步动物会消耗液体以维持生存。
10 .Although they have teeth, they don’t use these for chewing.
虽然它们有牙齿，但并不用它来咀嚼。
11 .They suck the juices from moss, or extract fluid from seaweed, but some species prey on other tardigrades, from other species or within their own.
它们吮吸苔藓的汁液，或从海藻中提取液体。但有些种类会捕食其他种类的缓步动物或本种类的其它缓步动物。
12 .I suppose this isn’t surprising, given that tardigrades are mainly comprised of liquid and are coated with a type of gel.
我想这并不奇怪，因为缓步动物主要由液体组成，并且其表面附有一种凝胶。
13 .Finally, I’d like to mention the conservation status of tardigrades.
最后，我想提一下缓步动物的保护状况。
14 .It is estimated that they have been in existence for approximately half a billion years and, in that time, they have survived five mass extinctions.
据估计，它们已经存在了大约 5 亿年，在此期间，它们经历了五次大灭绝并存活至今。
15 .So, it will probably come as no surprise to you, that tardigrades have not been evaluated by the International Union for Conservation of Nature and are not on any endangered list.
因此，这可能并不让你感到惊讶,世界自然保护联盟并没有对缓步动物开展评估，也没有将它们列入任何濒危名单。
16 .Some researchers have described them as thriving.
一些研究人员称它们正在繁荣生长。
17 .Does anyone have any questions they’d like to ask?
大家有什么问题想问吗？