The Human Body: Life Story 生命物语-7

They haven't changed because their environment has stayed the same. The water they live in bubbles up from deep in the earth, and so it's always the same temperature. But just meters away the environment is very different, away from the thermal¹ vents² with the ebb³ and flow of the water, the temperature fluctuates. Billions of years ago, bacteria were living here too, but as their living conditions changed, they changed as well. From one generation to the next, there were minute alterations⁴. In themselves they were almost insignificant⁵, but these tiny changes started the most amazing process.

--Because if you add up enough tiny changes from generations through millions of generations, you can get a revolutionary transformation⁶.

From being simple bacteria the creatures in these pools became more complicated. Single cells became groups of cells, and groups of cells (became) early plants and animals, and the changes continued. Dozens of species became hundreds, and hundreds turned into tens of thousands. Parts of bodies were adapted to meet new challenges. Great leaps were made. A fish's fins⁷ over countless⁸ generations developed into legs and it became a reptile⁹. Some reptiles¹⁰ developed feathers and became birds. Others became mammals in every shape and size from blue whale to baboon¹¹, every creature we see on the earth today including ourselves. All these happened. It's the miracle of evolution. The human body is just one branch in the huge spreading tree of life that grew from those simple bacteria.

Yet we carry with us the remnants of what has gone before us in our strange past, and there is a place we can go to see just one of those remnants, shaped by one of evolution's truly incredible transformations¹². It's inside my own head. All we need to do is go and find it.

This is my eardrum, a thin skin stretched tight across my ear canal. But what I want to show you lies on the other side of my eardrum. This device can take me there. I'm inside a huge magnet with a field strong enough to lift a car clean off the ground. It's a magnetic resonant¹³ scanner and it can reveal layer by layer what's inside my head. Up to now, this has been the forefront of medical imaging, but we are about to take it one step further.

By putting the medical scans together, we've created a 3-dimensional picture of my own head and I can look at any part of it that I want.

words and expressions

thermal : Of, relating to, using, producing, or caused by heat.
热的：有关、用、产生热的或由热造成的

ebb and flow :潮的涨落,盛衰,消长

minute:Exceptionally small; tiny微小的, 异常小的，极细微的

baboon:狒狒

remnant:A surviving trace or vestige:
遗留下来的痕迹或者残余

eardrum:耳膜

field:magnetic field:磁场

resonant :Producing or exhibiting resonance:
共鸣的，共振的：产生或显示共鸣的

1 thermal   

adj.热的，由热造成的；保暖的

参考例句：

• They will build another thermal power station.他们要另外建一座热能发电站。
• Volcanic activity has created thermal springs and boiling mud pools.火山活动产生了温泉和沸腾的泥浆池。

2 vents   

（气体、液体等进出的）孔、口( vent的名词复数 )； （鸟、鱼、爬行动物或小哺乳动物的）肛门； 大衣等的)衩口； 开衩

参考例句：

• He always vents his anger on the dog. 他总是拿狗出气。
• The Dandelion Patch is the least developed of the four active vents. “蒲公英区”在这四个活裂口中是发育最差的一个。

3 ebb   

vi.衰退，减退；n.处于低潮，处于衰退状态

参考例句：

• The flood and ebb tides alternates with each other.涨潮和落潮交替更迭。
• They swam till the tide began to ebb.他们一直游到开始退潮。

4 alterations   

n.改动( alteration的名词复数 )；更改；变化；改变

参考例句：

• Any alterations should be written in neatly to the left side. 改动部分应书写清晰，插在正文的左侧。 来自《简明英汉词典》
• Gene mutations are alterations in the DNA code. 基因突变是指DNA 密码的改变。 来自《简明英汉词典》

5 insignificant   

adj.无关紧要的，可忽略的，无意义的

参考例句：

• In winter the effect was found to be insignificant.在冬季，这种作用是不明显的。
• This problem was insignificant compared to others she faced.这一问题与她面临的其他问题比较起来算不得什么。

6 transformation   

n.变化；改造；转变

参考例句：

• Going to college brought about a dramatic transformation in her outlook.上大学使她的观念发生了巨大的变化。
• He was struggling to make the transformation from single man to responsible husband.他正在努力使自己由单身汉变为可靠的丈夫。

7 fins   

[医]散热片；鱼鳍；飞边；鸭掌

参考例句：

• The level of TNF-α positively correlated with BMI,FPG,HbA1C,TG,FINS and IRI,but not with SBP and DBP. TNF-α水平与BMI、FPG、HbA1C、TG、FINS和IRI呈显著正相关，与SBP、DBP无相关。 来自互联网
• Fins are a feature specific to fish. 鱼鳍是鱼类特有的特征。 来自辞典例句

8 countless   

adj.无数的，多得不计其数的

参考例句：

• In the war countless innocent people lost their lives.在这场战争中无数无辜的人丧失了性命。
• I've told you countless times.我已经告诉你无数遍了。

9 reptile   

n.爬行动物；两栖动物

参考例句：

• The frog is not a true reptile.青蛙并非真正的爬行动物。
• So you should not be surprised to see someone keep a reptile as a pet.所以，你不必惊奇有人养了一只爬行动物作为宠物。

10 reptiles   

n.爬行动物，爬虫( reptile的名词复数 )

参考例句：

• Snakes and crocodiles are both reptiles. 蛇和鳄鱼都是爬行动物。 来自《简明英汉词典》
• Birds, reptiles and insects come from eggs. 鸟类、爬虫及昆虫是卵生的。 来自《现代汉英综合大词典》

11 baboon   

n.狒狒

参考例句：

• A baboon is a large monkey that lives in Africa.狒狒是一种生活在非洲的大猴子。
• As long as the baboon holds on to what it wants,it's trapped.只要狒狒紧抓住想要的东西不放手，它就会被牢牢困住。

12 transformations   

n.变化( transformation的名词复数 )；转换；转换；变换

参考例句：

• Energy transformations go on constantly, all about us. 在我们周围，能量始终在不停地转换着。 来自辞典例句
• On the average, such transformations balance out. 平均起来，这种转化可以互相抵消。 来自辞典例句

13 resonant   

adj.(声音)洪亮的，共鸣的

参考例句：

• She has a resonant voice.她的嗓子真亮。
• He responded with a resonant laugh.他报以洪亮的笑声。