游走在边缘的生命Life on the edge

Hello and welcome to 6 Minute English. I’m Alice…
大家好，欢迎收听六分钟英语，我是爱丽丝。
And I’m Neil.So Alice, what’s your ideal place to be?
我是尼尔。爱丽丝，你最理想的地方是什么样子的？
Curled up on the sofa with a good book in front of a log fire.Last night it was very cold.
拿一本书缩在沙发里，坐在壁炉前。昨晚太冷了。
Well, for me, lying in a hammock under a palm tree on a tropical beach with a cool breeze. I don’t like when it’s too hot.
对我来说是躺在棕榈树下的吊床里，热带沙滩上吹来阵阵凉风。我不喜欢太热的时候。
Yes, true. Humans don’t cope well with extremes of temperature but some species do.The subject of today’s show is extremophiles– these are microorganisms that have adapted to live in what we would consider to be extreme conditions. For example, living in near boiling acidic water or frozen at the bottom of an Antarctic lake.
没错，人类不能应付极端的温度，但一些物种可以。今天节目的主题是极端微生物，是指可以适应我们所认为的极端环境的微生物。例如，存活于滚烫的酸性水中，或冰冷的南极湖底。
Those do sound like pretty extreme conditions.
这些听起来都是很极端的环境。
Yes. The thing is, what sounds hostile – or unfriendly – to us, are perfect environments for extremophilesand in fact they wouldn’t survive without them.Now, are you tough enough to face up to today’s quiz question, Neil?
没错，对我们来说充满敌意的环境，对极端微生物来说再完美不过。事实上没有这种环境，它们无法存活。你足够坚强来面对今天的问题吗？
I think so.
我觉得没问题。
Alright then, here goes: which US National Park is home to geysers – or hot springs that shoot hot water and steam into the air– which have extremophiles living in them? Is it…a) Grand Canyon?b) Death Valley National Park?Or c) Yellowstone?
好的，问题是：那个美国国家公园有间歇泉，也就是喷出热水，并冒有蒸汽的温泉，其中有极端微生物存活？a) 大峡谷？b) 死亡谷国家公园？还是c) 黄石公园？
That’s easy - it has to be c) Yellowstone.
很简单，一定是c) 黄石公园。
OK, well we’ll find out if you got the answer right later on in the show.But, moving on, now, Neil, did you know that extremophiles belong to an entirely different group of living things to other animals and plants?
好的，之后我们再看你回答得是否正确。现在我们继续说，尼尔，你知道吗，极端微生物和其他动植物相比，属于完全不同的生物群。
No. I imagined extremophiles would be like insects, because insects are pretty tough, aren’t they?
不知道。我以为极端微生物和昆虫一样，因为昆虫生命力很顽强，不是吗？
Yes, that’s true. But remember, extremophiles are microorganisms – they’re really tiny.Let’s listen to Ian Crawford, Professor of Planetary Science and Astrobiology at Birkbeck University of London.He tells us how in the 1970s a scientist called Carl Woese identified a new kingdom of living things that he called archaea– meaning ancient ones.The extremophiles belong to this group.
这没错。但要记住，极端微生物属于微生物，他们非常小。我们听听伦敦大学伯贝克学院行星科学和天体生物学教授 Ian Crawford的看法。他会讲述20世纪70年代，一位名叫Carl Woese的科学家如何发现他称之为古生菌的新生物王国。archaea 是指古代的生物。极端微生物就属于这个群体。
Well, the old tree of life idea basically talked about empires if you like, of plants, and animals, and things that we can see, essentially. We put a great deal of emphasis on large organisms and the traditional distinction in biology between botany and zoology.What it really did was say that’s all wrong– there’s really only three major groups in life:there’s the archaea, the bacteria, and the eukaryotes, which is all of this complex life;and so it kind of put humans into a small corner of the tree of life next to plants and whatever else.It kind of squashes us again after being the centre of the universe.
之前生命树基本上谈论植物王国、动物王国及我们能看到的事物。我们将重点放置于大的生物体，以及传统地将生物划分为植物学和动物学的观点。古生菌的存在说明之前的观点是错误的，生命有三大类：古生菌、细菌和真核生物，即所有复杂的生命。所以人类仅是生命树的一角，和植物等并列。这让自以为是宇宙中心的我们再次受挫。
So botany is the study of plant life, and zoology is the study of animal life.But maybe you can explain archaea, and eukaryotes, Alice.
所以 botany是研究植物的学科，zoology 是研究动物的学科。也许你应该解释一下古生菌和真核生物。
Archaea are a group of single-celled microbes similar to bacteria but different to all other known types. Eukaryote is the scientific term for organisms with a much larger and more complex type of cell– and this group includes all animals, plants, and fungi.
古生菌是指单细胞微生物，类似于细菌，但是和已知的细菌类型不同。真核生物是指具有更大更复杂细胞的生物体，这一类包括所有的动物，植物和真菌。
But why are archaea so important?Why do they need a whole biological domain to themselves, while we humans get squashed up in one domain with plants and fungi?
为什么古生菌如此重要？为什么它们会占据整个生物分支？然而我们人类要和植物、真菌挤在一个分类里？
Well, Neil, it’s likely they’ve have been living on our planet ever since the Earth became habitable– and that’s billions of years. And they are still living and thriving in a whole range of different environments today.
尼尔，似乎自地球成为宜居的星球起，它们就已经存在了。已经有几十亿的光景了。如今它们依旧在不同的环境中欣欣向荣。
And when something is thriving it means it’s doing well! So tell us about where they live, Alice.
thriving是指某物不错。爱丽丝，讲讲古生菌在哪里存活吧。
Some live in hydrothermal vents – holes in the ocean floor hundreds of metres down where there’s lots of pressure and no sunlight. And mineral-rich superheated water is coming out of the Earth’s crust and then flowing out through these holes.
一些存活于喷汽口，据海平面上千米以下的洞，那里压力很大，没有光照。矿物质丰富的过热水来源于地壳，然后从这些洞流出。
I see… Well, what about cold-loving extremophiles?
我明白了。那喜欢寒冷环境的极端微生物呢？
Well, scientists have found them in hidden lakes trapped beneath ice sheets hundreds of metres thick in Antarctica.It takes days to drill through the ice to reach the water.
科学家在隐藏于南极上千米厚的冰层下的湖水中发现了极端微生物。要花费好几天才能把冰打穿，够到湖水。
And how do they survive down there?
他们怎么存活的呢？
Well, these microbes have found a way of getting energy from certain minerals like iron and sulphur present in the water.
这些微生物会从水中的一些矿物质获取能量，如铁和硫磺。
That sounds clever for a microbe – how did they figure that out?
听上去微生物很聪明，他们怎么能辨认出呢？
It isn’t a question of cleverness - it’s a question of adaptation.Extremophiles are extremely well adapted to their environment and they appeared on Earth much earlier than more complex life forms.Let’s hear from Nick Lane, Reader in Evolutionary Biochemistry at University College London.
这不是聪不聪明的问题，而是适应能力的问题。极端微生物能够极好地适应环境，他们比更复杂的生命形式更早地出现在地球上。我们听听伦敦大学学院进化生物化学的学者 Nick Lane的看法。
The origin of the Eukaryotic cell, it seems to have happened once, it took about 2 billion years before that happened.Then there was kind of a great leap forward at the cellular level,but another billion years went by before we see animals.
真核细胞的起源，似乎是只出现过一次，花费了20亿年才出现。之后在细胞方面有了跳跃式的发展，但几十亿年后，我们才看到动物出现。
So, basically, the animal kingdom is much newer than the archaean kingdom.
所以，动物王国比古生菌出现的晚。
Indeed. And now it’s time for the answer to today’s quiz question, Neil.I asked: which US National Park is home to geysers that have extremophiles living in them?Is it… a) Grand Canyon, b) Death Valley National Park or c) Yellowstone?
没错，是时候公布今天问题的答案了。我问你：美国哪一个国家公园有间歇泉，其中生存着极端微生物？a) 大峡谷， b) 死亡谷国家公园，还是 c) 黄石公园？
And I said c) Yellowstone. I must be right.
我选黄石公园，一定是它。
Yes, Neil, you are right - it’s Yellowstone National Park.Every year, scientists discover remarkable new microbes in Yellowstone’s hot springs, with implications for medicine, agriculture and energy, as well as offering clues to the formation of the earliest life on Earth.
没错，尼尔，你答对了。是黄石国家公园。每年，科学家们会在黄石的温泉中发现新的微生物，对医药、农业和能源方面产生重大影响，同时也为地球上早先生命的形成提供了研究线索。
Very interesting. Now, here are the words we heard today:
很有意思。现在我们听听今天学到的单词。
extremophiles
极端微生物
hostile
敌对的，不友好的
geysers
间歇泉
microorganisms
微生物
botany
植物学
zoology
动物学
archaea
古生菌
eukaryote
真核生物，真核细胞
thriving
繁盛的，欣欣向荣的
hydrothermal vents
深海热泉，喷汽口
And that’s the end of today’s 6 Minute English. Don’t forget to join us again soon!
今天的六分钟英语就到这里。别忘了下次再会！
Bye!
再见！