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  • Chimps can be three to five times stronger than humans.

  • That means a really strong chimp could, in theory,

  • lift around sixteen people over its head.

  • But, can eating bananas and swinging around in trees

  • really account for this difference?

  • After all, aren't we supposed to share 99% of our genes?

  • Studies have shown differences in the way our muscles are built

  • but muscle control may be a much more important factor

  • Chimps seem to have less control over how much muscle they use at once.

  • While this may sound counter-intuitive, this can account for the difference in strength.

  • Let's take a look at why.

  • Compared to humans, chimps have less gray matter relative to body weight.

  • Gray matter is the part of the nervous system

  • that contains the nerves responsible for controlling motion.

  • These branch out from the spine into the muscles

  • to control individual muscle fibers.

  • Some neurons can contact many muscle fibers at once.

  • Activating these neurons causes all of the muscle fibers that touches

  • to contract at once.

  • Creating a lot of force.

  • This combination of neurons and muscle fibers

  • is called the large motor unit.

  • And these are used for gross motor skills

  • like jumping and climbing.

  • Some neurons contact only a few fibers

  • making a small motor unit.

  • These don't have a lot of power

  • but they are a lot more precise.

  • Small motor units let us do delicate complex tasks

  • like playing a video game or plucking a ukulele.

  • Things that we can do and

  • chimps can't.

  • So chimps who have less gray matter

  • have fewer motor neurons.

  • Therefore, their motor neurons are more likely

  • to be dedicated to large motor units.

  • This means when they do engage their muscles

  • it's an all-or-nothing response which we see as strength.

  • Unlike chimps, our neurons control smaller bundles

  • so we have more specific muscle control.

  • So keep this in mind the next time you think of challenging a chimp in a pub;

  • You might want to try thumb wrestling instead.

  • For Scientific American, I am Yasmin Tayaq.

Chimps can be three to five times stronger than humans.

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黑猩猩为什么比人类更强大(Why Are Chimps Stronger Than Humans? - Instant Egghead #30)

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    joey joey 發佈於 2021 年 05 月 15 日
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