摘要：摊开手掌，将掌心面向自己，然后使劲儿握拳，有没有发现，你的手腕中间绷起一条5mm左右的“筋”？
摊开手掌，将掌心面向自己，然后使劲儿握拳，有没有发现，你的手腕中间绷起一条5mm左右的“筋”？
就像图中这样：
这条“筋”实际上是一块肌肉，名为“掌长肌”，英文名为long palmar(手掌的) muscle。
如果你没有在自己手腕处发现它，说明你属于独特的1%左右的中国人。
为什么有的人有掌长肌，有的人却没有？
目前一般认为，掌长肌是人类在进化过程中慢慢被“放弃”的一块肌肉。
很久很久以前，当人类始祖还在树上活动时，掌长肌作为抓握攀爬所用到的关键肌肉，曾经非常发达。
但当人类走出森林，开始直立行走后，掌长肌便失去了它的作用，变得越来越弱。
而那些早早从树上下来的早的群体，也就抢先放弃了掌长肌。
所以，如果你没有这块肌肉，说明在远古的人类起源年代，你们家的始祖比别人先爬下树，学会了直立行走。
说到这里，不得不讲讲muscle这个词。
看到muscle时，有没有人会联想到mouse（老鼠）？
虽然这两者如今大不一样了，可在最开始，muscle因小老鼠而得名。
爱健身的古罗马人发现，上臂弯曲时的肌肉很像跑动的小老鼠，于是将其叫作musculus（小老鼠mus）。该词传入法国后又进入英国，最终演变成今天的muscle。
muscle 常见释义有：
1
肌肉
strengthen / build up muscles 增强肌肉
When you walk you exercise your leg muscles.
走路能锻炼腿部肌肉。
2
muscle labour 力气活
提到muscle，最后再讲一下读后续写中常常用到的“动作描写”。
很多同学在动作描写中得不到高分，不妨试试：
TOP 01
用精准动词代替笼统动词
1. 笼统动词：look
精准动词：glance, gaze, stare, peer,
原句：He looked at the painting.
改写：He gazed at the painting, fascinated by its beauty.
2. 笼统动词：say
精准动词：whisper, shout, murmur, scream, declare
原句：She said something to him.
改写：She whispered something to him, her voice barely audible.
3. 笼统动词：go
精准动词：rush, stroll, sprint, wander, march
原句：He went to the store.
改写：He rushed to the store, eager to buy the last ticket.
4. 笼统动词：take
精准动词：grab, seize, capture
原句：She took the book from the table.
改写：She grabbed the book from the table, her eyes scanning the pages.
5. 笼统动词：move
精准动词：shift, slide, stroll, stride, wander
原句：He moved in the seat.
改写：He shifted a little in his seat, feeling uncomfortable.
6. 笼统动词：put
精准动词：place, set, drop, throw, arrange
原句：He put the vase on the table.
改写：He carefully placed the vase on the table, ensuring it was centered.
7. 笼统动词：feel
精准动词：touch, caress, pat, squeeze
原句：She felt the soft fur of the cat.
改写：She gently caressed the soft fur of the cat, feeling its warmth.
8. 笼统动词：make
精准动词：construct, create, assemble, prepare
原句：He made a model airplane.
改写：He meticulously constructed a model airplane, paying attention to every detail.
9. 笼统动词：do
精准动词：perform, execute, accomplish, complete, fulfill
原句：She did her homework.
改写：She diligently completed her homework, double-checking her answers.
10. 笼统动词：see
精准动词：notice, observe, glimpse, stare at, watch
原句：He saw a bird in the tree.
改写：He noticed a bird perched on a branch, its feathers shimmering in the sunlight.
TOP 02
用恰当短语代替普通动词
1.普通动词run
短语：dash out
例句：He dashed out of the house to catch the bus.
2.普通动词start/begin
短语：get down to doing
例句：We need to get down to solving this problem before it gets worse.
3.普通动词 decide
短语：make up one’s mind
例句：They made up their minds to travel around the world before they got too old.
4.普通动词 cry
短语：burst into tears
例句：He burst into tears when he saw the surprise his friends had prepared for him.
5.普通动词 remember
短语：keep...in mind
例句：My teacher told me to keep in mind the importance of time management.
6.普通动词tired
短语：worn out
例句：After a long day at work, she felt completely worn out.
7.普通动词 attract
短语：appeal to
例句：The idea of traveling around the world really appeals to me.
8.普通动词 smile
短语：grin from ear to ear
例句：When she saw her surprise gift, she grinned from ear to ear.
你的掌长肌还在吗？
来源：维词