英语新闻听写 科学家发现左撇子的真正原因

About 10% of the population is left-handed.

大约10%的人口是左撇子。

There have been several theories over the years about why some people favour their left hand.

为什么有些人喜欢用左手，关于这个问题，多年来已经有不少理论。

A study from last year has shown that it might be nothing to do with your brain.

去年的一项研究表明，这可能与大脑无关。

Rather, it could be determined¹ by your spinal² cord while you are in the womb.

相反，这可能在出生前就由脊髓决定了。

Research which was led by scientists from the Netherlands and South Africa found that gene³ activity in the spinal cord is already asymmetrical⁴ in the womb, and this could be what causes left or right-handedness.

荷兰和南非的科学家们研究发现，脊髓中的基因活动在子宫中已经不对称，这可能是导致左或右利的原因。

While the baby is growing in the womb, up until about 15 weeks, the motor cortex and the spinal cord are not yet connected, but right or left-handedness is already decided⁵.

胎儿在子宫里生长的时候，直到大约15周，运动皮质和脊髓才相互连接，但是这时喜欢用哪只手已成定局。

1 determined   

adj.坚定的；有决心的

参考例句：

• I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
• He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。

2 spinal   

adj.针的，尖刺的，尖刺状突起的；adj.脊骨的，脊髓的

参考例句：

• After three days in Japan,the spinal column becomes extraordinarily flexible.在日本三天，就已经使脊椎骨变得富有弹性了。
• Your spinal column is made up of 24 movable vertebrae.你的脊柱由24个活动的脊椎骨构成。

3 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

4 asymmetrical   

adj.不均匀的，不对称的

参考例句：

• Most people's faces are asymmetrical.多数人的脸并不对称。
• Folds may be gentle and symmetrical,or sharp and asymmetrical.褶皱可以是平缓而对称的，也可以是陡峭而非对称的。

5 decided   

adj.决定了的，坚决的；明显的，明确的

参考例句：

• This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
• There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。