
Elastic energy storage in the shoulder: evolution of high-speed throwing in Homo - bookofjoe
https://www.nature.com/articles/nature12267
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joe5150
Open access article:
[https://dash.harvard.edu/bitstream/handle/1/11879202/3785139...](https://dash.harvard.edu/bitstream/handle/1/11879202/3785139.pdf?sequence=1)

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sunstone
While throwing for hunting purposes would have been useful, throwing for
defensive purposes likely would have been the initial impetus for throwing
evolving to a fine art.

Imagine yourself alone on the plains of Africa and facing a lion or two. Your
odds are not good. Even a group of people on the plains of Africa facing a few
lions with no ability to throw stones looks like a losing proposition.

However a group of people in an outward facing circle facing lions and each
with a pile of stones to throw with deadly accuracy, now this is something
that even lions would think twice about.

The thing about defence is you don't have to move, the stones are prepared
before hand. The predator has to come to you and is therefore easier to hit,
preferably in the head. Sticks and stones will break their bones but names
will never hurt them.

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dkarl
I agree with your point, but I would expand on it to say that defense could
have even more important implications for scavenging than for surviving
predation. Being able to scare predators off a kill [1] makes scavenging a lot
easier. And then you can apply the same means to hunting, which is also more
fruitful because you can hold your own kills.

You wouldn't even need to be strong enough for lions to start with; every step
up the pecking order would be an advantage.

I don't envy paleontologists and archaeologists trying to make a case for
"why" an adaptation emerged when it has so many plausible advantages,
especially when cultural developments might have happened too fast or at too
great a distance in the past for us to have an accurate idea of their timing.

[1]
[https://www.youtube.com/watch?v=TBpu4DAvwI8](https://www.youtube.com/watch?v=TBpu4DAvwI8)

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sunstone
Some very good points here :)

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nickhalfasleep
And now I push a mouse around on a desk with this amazing arm.

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dkarl
Just don't reproduce, and you'll keep our evolutionary trajectory on track. In
a few generations we'll be able to throw the CO2 so far it never bothers us
again.

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defen
Interestingly enough, throwing is the human trait / behavior with the biggest
known measured disparity between the genders on average (this includes
physical, mental, and emotional abilities).

See Table 1
[https://www.apa.org/pubs/journals/releases/amp-606581.pdf](https://www.apa.org/pubs/journals/releases/amp-606581.pdf)

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xyzzyz
_The largest gender differences in Table 1 are in the domain of motor
performance, particularly for measures such as throwing velocity (d = 2.18)
and throwing distance (d = 1.98)_

The Cohen's d value here is difference in means between two populations,
normalized by the pooled standard deviation. What d = 2 means in concrete
terms is that an average man can throw faster and further than ~98% of women.

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b_tterc_p
It’s surprising to me that throwing isn’t more instinctual. If not taught how
to throw, people will generally throw things by extending their elbows from
their chest. This is “throwing like a girl” though it doesn’t really have
anything to do with gender except we teach boys how to throw things.

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sambroner
I wonder when the common overhand throw was first tried out. Presumably, it
was an evolution, but Id guess the first attempt was more of a fling...

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clairity
neat! i studied the related phenomenon of locomotion by swinging and we
postulated that elastic energy storage (and release) in the shoulder was an
important part of the energetics and efficiency of that form of locomotion.

