The Human Body: Life Story 生命物语-9

Millions of years ago, the embryo¹ of a distant ancestor of ours would have shared with us many of these features. As well as giving rise to us, it gave rise to all sorts of other creatures. And in those creatures, these features we're looking at here have evolved quite differently. We can actually see it happening with the ear bones, because those very same grooves² that in us would have become our ear bones, in this creature become something else entirely³. This is the embryo of a fish. Here is its heart. And it too has a curved spine⁴ and the tiny grooves here, just a fraction of a millimeter long, have evolved to become not ear bones, but supports for its gills.

So, sometime long, long ago, this sort and I shared a common ancestor. And like them it too had little bones around its gills which helped it to breathe. But as we evolved, these little bones were adapted for an entirely different job purpose to become the intricate mechanism⁵ of our ears.

And our ear bones are not the only things to have been transformed in this way. Such apparent miracles are in fact all around us. The rest of our ears that allow us to balance and walk upright as well as hear, our limbs and hands, our whole body has been shaped by the process of evolution.

Everything about the human body has been inherited and adapted from something our ancestors had a long time ago. Even though they may have used it for something entirely different, we are recycled from the past.

Once we begin to understand the source from which our bodies are derived, the way we look at ourselves can never be quite the same again. So every part of the human body bears a shadow from our distant past. Evolution has adapted our bodies from those of our ancestors, all the way back since life was as simple as that in the steaming pools of three billion years ago. It is incredible...

words and expressions

derive:To issue from a source; originate.起源于，来自

1 embryo   

n.胚胎，萌芽的事物

参考例句：

• They are engaging in an embryo research.他们正在进行一项胚胎研究。
• The project was barely in embryo.该计划只是个雏形。

2 grooves   

n.沟( groove的名词复数 )；槽；老一套；（某种）音乐节奏v.沟( groove的第三人称单数 )；槽；老一套；（某种）音乐节奏

参考例句：

• Wheels leave grooves in a dirt road. 车轮在泥路上留下了凹痕。 来自《简明英汉词典》
• Sliding doors move in grooves. 滑动门在槽沟中移动。 来自《现代汉英综合大词典》

3 entirely   

ad.全部地，完整地；完全地，彻底地

参考例句：

• The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
• His life was entirely given up to the educational work. 他的一生统统献给了教育工作。

4 spine   

n.脊柱，脊椎；(动植物的)刺；书脊

参考例句：

• He broke his spine in a fall from a horse.他从马上跌下摔断了脊梁骨。
• His spine developed a slight curve.他的脊柱有点弯曲。

5 mechanism   

n.机械装置；机构，结构

参考例句：

• The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
• The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。

6 derived   

vi.起源；由来；衍生；导出v.得到( derive的过去式和过去分词 )；（从…中）得到获得；源于；（从…中）提取

参考例句：

• Many English words are derived from Latin and Greek. 英语很多词源出于拉丁文和希腊文。 来自《简明英汉词典》
• He derived his enthusiasm for literature from his father. 他对文学的爱好是受他父亲的影响。 来自《简明英汉词典》