Posted on 06/27/2002 3:31:49 PM PDT by blam
Man casts first stone
Stockpiling rocks as weapons may have preceded sculpting them into tools.
21 June 2002
JOHN WHITFIELD
A thrown rock can carry the force of a revolver bullet.
Our instinctive feel for the ideal projectile could explain the design of hand-grenades, the collecting habits of geologists, the size of handballs and the weight of the imperial pound, says an engineer.
Understanding that instinct could illuminate the lives of prehistoric hominids, believes Alan Cannell, who lives in Curitiba, Brazil. He thinks that selecting and stockpiling rocks as weapons may have preceded sculpting them into tools1.
For millennia, a thrown rock - which can carry the force of a revolver bullet - was probably our ancestors' most potent weapon against predators or competitors. But the rock needs to have the right mass: too light, and it won't do any damage; too heavy, and it can't be thrown with much force.
Cannell gave a group of young men a choice of rocks weighing between 180 and 1,900 grams, and told them to throw one at a target with the intention of causing maximum damage.
They all chose a rock weighing 480 grams. A mechanical analysis, based on arm length and strength, showed that this is very close to the weight that a man can throw with the most force.
Cannell also weighed the samples that had been picked up by geologists and deposited in his local museum. They averaged about 500 grams - this weight 'felt right', some of the researchers told him.
Most hand-grenades, he found, weigh just below 500 grams. And a men's handball weighs 455 grams. Our seemingly ingrained love of approximately half-kilogram weights may even explain the pound: it is 454 grams.
A women's handball weighs 365 grams. In Cannel's rock-choice experiment women liked 320-gram lumps - the weight they can lob with maximum force.
Rock steady
Many sites that were inhabited by humans' forebears are littered with rocks that seem to have been carried there but not turned into tools. These might have been hoarded for throwing, Cannell suggests.
"I can imagine hominids doing that," comments archaeologist Robin Dennell, of the University of Sheffield, UK. "For defensive purposes it makes a lot of sense."
I can imagine hominids hoarding rocks for throwing Robin Dennell, University of Sheffield
If prehistoric hominids did indeed select weapons from stony ground, the masses of the rocks at the places they lived should be similar, rather than a random selection. This mass would also tell us how big the hoarders were.
Cannell now wonders whether our brains might bear the marks of our rock-throwing past. He is teaming up with neuroscientists to see what happens when a person hurls a rock.
"We are looking for something hardwired that recognizes the ideal mass and is involved in throwing," he says. "This would show that throwing was, at some stage of our evolution, of vital importance."
References Cannell, A. Throwing behaviour and the mass distribution of geological hand samples, hand grenades and Olduvian manuports. Journal of Archaeological Science, 29, 335 - 339, (2002).
We have known this for years, if not forever. Our upright posture and our brains evolved so we could throw rocks and hunt, mainly for rabbits.
Yup. I read somewhere that a batter does 200 million calculations before swinging at a baseball.
In artillery terminology it is called; "Solving for the Target Solution". Simply put, it is hitting what you aim at.
The computer used for the Nike Hercules Missile was the size of three refrigerators that did the computations for intercept at supersonic speeds. The laptop that I input this post on is many times more powerful than the Nike computer.
Prometheus
Some theorize that man first walked erect,
To carry simple tools, or throw a spear,
The fossil record proves this incorrect:
Walking predates tools, two million years.
Others think that walking freed the hands,
To gather and to carry precious food,
But this selects the group and not the man,
And won't select at all when times are good.
I think 'twas fire that taught the ape to stand,
It's fearful, but it's pretty, warm and bright,
One stoopéd ape picked up a fire-brand,
And banished cold, and predators, and night.
Encumbered, thus unfettered, torch in hand,
An ape, tempered by fire, became a man.
Granted, I can't rule out that they were carrying rocks around as weapons, but it seems unlikely that they could carry enough rocks to represent a huge advantage over simply picking up whatever rocks were lying around. Throw one or two rocks and you've shot your wad. A stockpile is a big help, but there's no strong need to walk upright in order to make one; chimps could do it, if they had a mind for it.
Actually it uses rules of thumb. No calculations involved, just lots of practice and an ability to learn quickly what works, what doesn't, and refine it.
If we had to use math every time we did anything it is likely we would not be able to cross the street without being run over. Our brains simply cannot calculate quickly enough.
Read "The Society of Mind" by Marvin Minsky for an interesting analysis of how the mind works.
But it was nothing more than looking direct
Over tall grass, to judge if game were near.
Hmm. Hominids had not yet invented meter...
It seems that most men look upon a pile of rocks and see a realy neat collection of deadly weapons. Man's rise and affinity for weapons are intimately intertwined.
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