From the Vault: Humans Throwing Stuff

in the previous episode. But also in the previous episode we ended up talking about the evolution of the human capacity for throwing, which we are particularly apt at Humans are very good at throwing, especially compared to our nearest primate relatives. So like a chimpanzee maybe on average three or four times stronger than a human, But a human, even without specialized training, can generally throw a lot more forcefully and a lot better than a chimpanzee can. So

why are we so specialized for throwing? Well, we took a look at some evolutionary hypotheses about where our capacity for throwing comes from. But there was another thing that I came across while researching this subject that I did not get into in the previous episode, and I wanted to come back to it here because I found it

really interesting. And this is the idea of what if the evolution of throwing was somehow a necessary precursor for the evolution of probably the most distinctly human trait language, So not just that humans are good at throwing and good at language, but that there is actually a neurobiological

link between the two one comes from the other. So to look at this question, I wanted to refer to a paper by William D. Hopkins, Jamie L. Russell, and Jennifer A. Schaeffer published in Philosophical Transactions of the Royal Society b Biological Sciences, published in twenty twelve, called the Neural and Cognitive Correlates of Aimed Throwing in Chimpanzees a magnetic, resonance, image, and behavioral study on a unique form of social tool use. So to begin, they cover some of the same ground

we did in the previous episode. You know how unusual he when throwing behavior is in a way, and despite all the interesting examples we've discussed in these episodes of animals throwing things for various reasons, whether trained by humans or just doing it as part of their natural instinctual behaviors, the authors here argue that in general, throwing remains unsystematic, in their words, in other animals, And I think this

is fair. No other animal practices the kind of generalized, skillful habitual throwing that we do, certainly not without training by humans.

even though we're not a baseball or softball family. But it was just kind of the thing that I guess was like nostalgic in the culture, but also very satisfying to do and something that even if you're not very practiced at you can do with some or at least I found that I could do with some degree of precision, despite being very rusty at the whole softball baseball thing.

favor forceful overhand throwing. I remember those changes. They're changes in the shoulder and the waist and the upper arm, all of which combined to allow for a more substantial wind up, sort of a pulling back of tension of the biomechanical bowstring to be released rapidly during the throw.

And we also talked about the argument that these changes appear to coincide with evidence of meat becoming a bigger part of the diet of these hominins, showing that throwing was likely useful for obtaining food, either through power scavenging like driving predators away from a kill in order to take the meat for yourself, or direct hunting, and either

way increasing the availability of food energy. Now, one very interesting thing about the adaptation for throwing is that it implies not only changes in the muscles and the skeletal system. Of course, you know, you can see all those changes around the scapula and the shoulder blade, changes in the waist, the arm, and so forth, But it also implies changes in cognition. An animal that can throw objects sourced from the environment is showing a specialized way of thinking, and

not just a specialized way of moving. Now what do I mean by this? Well, as one example, the authors reference a specific captive chimpanzee who came up in the last episode. Robie, remember the story of Santino, the chimpanzee who was in a zoo and I believe Sweden was it?

when the visitors arrive. That is a crafty chimp, and that is forethought. Adding to this, the authors throw in their own observations of similar pre planning behavior in chimpanzees in two other research environments, and they argue that the throwing quote, though often agonistic in function and consequence, agonistic meaningless confrontational aggressive behavior, is not part of the ape's

display behavior. Indeed, most instances of aimed throwing that we have observed occur without any accompanying display behavior such as pilo erection, hooting, and charging, further suggesting an element of

planning on the part of the individual ape. So I think that's interesting too if you understand what they're saying there, that there is a sort of standard display behavior algorithm, like when an ape is doing an agonistic display when trying to be dominant and aggressive and maybe scare you off. It includes all of these sub features like the pilo erection meaning the bristling of body hair, hair stands on end, hooting,

charging back and forth, all that stuff. And they say that when the apes throw stuff at people, they do it without all of these other features of a typical instinctual display. Another way that throwing is different from most other forms of tool use and apes. The most commonly observed types of tool use by wild chimpanzees are all things where the tool is used to extract otherwise unreachable food, often like from a hole or enclosure of some kind,

and then is eaten immediately. So examples here would be cracking of nuts with stones like nut cracking is an example of ape tool use, but also termite fishing with sticks, ant dipping, and so forth. All of these give rise to an immediate food reward for executing the behavior, meaning that these behaviors are subject to regular operant conditioning rules. You know, if a behavior leads to an immediate food reward, an animal can learn to repeat basically any arbitrary set

of actions. So you know, chimpanzee gets delicious termites every time it. Of course, if it dips for them, that's one thing. But maybe if it stands on one foot and gets termites every time, it may learn to stand on one foot to get the meat.

What appears to be the main reward for throwing is the simple ability to control or manipulate the behavior of the targeted individual ape or human, which, though you could consider it a goal, I mean that is much more complicated and ambiguous than a direct food reward.

physical properties of the projectile and so forth. But then the other thing is the sequential motor control. To throw an object, you have to precisely time a rapid sequence of muscular movements, and other authors have previously suggested that quote the increased selection for neural synchrony of rapid muscular sequencing. Routines associated with actions such as throwing are similar to the motor programming demands of language and speech, and therefore

engage similar neural systems, notably Broca's area. In other words, there are similarities between what the brain is doing and what parts of the brain are being used to coordinate a throw and to process language and speech. And one idea that gets wrapped up in this is the role of brain lateralization, segmenting of brain processes to one hemisphere

or side of the brain or the other. So in cultures where throwing behavior has been studied, the authors say the majority of people pretty much always prefer to throw with the right hand. Studies in chimpanzees also show a bias toward right handedness for throwing, and these right hand preferences suggest left hemisphere dominance in the brain in these majorities of both populations, because when it comes to controlling

the body's movements, of course, you know, the hemispheres are flipped. Generally, the left hemisphere links to the right hand, the right hemisphere to the left, and so forth. Some researchers have pointed this out in the context of the fact that the left hemisphere also contains the brain regions, notably Broca's area,

that dominate the production of speech. Broker's area is also known as the motor speech area, and one researcher who has focused on this is the American neurophysiologist William H. Calvin, who was actually, I think maybe still is a professor at the University of Washington at Seattle, who observing that eighty nine percent of people prefer to throw with the right arm, Calvin hypothesized that the left hemispher's capacity for language may have actually evolved from a pre existing adaptation

for right handed throwing. He apparently published a book that contained this hypothesis. In nineteen eighty three, it was called The Throwing Madonna.

stone of capacity for throwing. So the story goes like this, lateralization evolved for one handed throwing with the right hand, specifically so that parents, typically mothers, could cradle an infant on their left side and then they'd be free to

throw with the right hand if they needed to. So, I mean, obviously things like this are hard to prove for sure, but that is an interesting idea because I started thinking about how I recently became a father, and without thinking about it at all, I pretty much always when I hold my baby, hold her on the left side of my torso, and so if she like falls asleep against me, her head is going to be on the left side of my chest and from my point of view, which is also the side where the heartbeat

is closer. I never planned it that way, that that just sort of happened, and I was talking to my wife and she said, yeah, most often she's on the left side there too, So I don't know that that's kind of interesting. I mean, it could be totally unrelated, but I don't know.

is the real reason driving brain lateralization. I find it more compelling than some other hypotheses that seemed to be on offer at the time, one that cited I was reading a review of this book by Calvin that cited a previous hypothesis that the right handedness evolved because men in battle I guess prehistoric battle needed to hold a shield above their above their heart on the left side. I was like, I get out of here.

But she's standing here in some sort of a you know, a hide garment, and she has this heavy looking infant in her left arm, and then there's another child sort of hanging on to her left arm. In her right hand, she has uh like some sort of a stone weapon, like a wooden half with a with a stone blade, some sort of like you know, primitive acts or club.

And she's staring back into the shadows behind her with there's this kind of like cave environment, and there's clearly an animal lurking there or an animal emerging from the shadows. And I think this is supposed to be the other mother, the mother that is hunting her. And I have no

idea of this. This this piece has has any connection what we're talking about here, But it is interesting that we do see left arm cradling children, right arm brandishing a weapon to protect those children against some threat.

think of speech, and that could be the case. I think Calvin argued for a transitional state where the original language was more gesture based, like gesturing with the hands maybe, which would have then transitioned into speech production with the mouth. Again, like many things here, that's not something we know for sure, so we're in very speculative territory. But I do find

this really interesting. So again, if there's anything to this story, it would go that for some reason, there is an original right hand left brain motor lateralization for the majority of the population for throwing objects. Human ancestors get really good at throwing with that one hand, maybe cradling a

baby in the other arm or doing something else. And then you could argue that the lateralization for precise sequential motor activity and the left brain to power throwing eventually provides the neurological scaffolding for the left brain's capacity for language and speech. Now, what was the actual experiment in this study, Well, it was looking at our closest primate relatives to see if they could provide any insight on what might have been going on in the brains of

very distant human ancestors. So they were looking at chimpanzees. Now, again, chimpanzees don't throw nearly as well or as often as we do, but some throw sometimes, So what if anything is different in the brains of chimpanzees that reliably throw

versus those that don't. Specifically, the authors looked at the ratio of two different types of brain tissue, white matter and gray matter in the areas of chimpanzee brains that would be most similar to the areas of the human brain involved in motor control for throwing and for speech. And this would be quote the homologue to Broca's area. I remember again Broker's areas involved in speech production in humans.

And then they also say as well as the motor hand area of the precentral gyrus termed the knob, K and OB. And what they found was that in both of these areas, in the chimpanzee equivalent of Broker's area and in the knob. The ratio of white matter to gray matter was higher in chimpanzees that throw versus those that don't. Also quote, we further found that asymmetries in white matter within both brain regions were larger in the

hemisphere contralateral to the chimpanzee's preferred throwing hand. So what they're saying is it's not just that the ratio of white matter was higher in these regions on both sides of the brain. It's that whichever hand the chimpanzee liked to throw with those particular regions had a higher proportion

of white matter on the opposite side of the brain. Also, they assessed the chimpanzees in this study with what is called a Primate Cognition Test BATTERY or pct B, which is, you know, a sort of an SAT for chimpanzees, standard tests on all kinds of mental abilities, you know, tons of things, spatial memory, causality, inference, tool property, recognition, gaze following, and so forth. And they were looking at, well, are there any differences between apes that throw and apes that

don't throw? And out of this entire test battery generally not generally, there were no cognitive differences except in one area. There was only one aptitude where there was a significant difference, and it was that researchers found chimpanzees that were more inclined to throw were also better at social communication. So

the author's right quote. These results suggest that chimpanzees that have learned to throw have developed greater cortical connectivity that's correlating with the white matter between the primary motor cortex

and the Broca's area. Homologue, it is suggested that during hominine evolution, after the split between lines leading to chimpanzees and humans, there was intense selection on increased motor skills associated with throwing, and that this potentially formed the foundation for left hemisphere specialization associated with language and speech found in modern humans. So this is another case where I

think this is far from proven. We would need much more robust evidence before you could endorse this specific evolutionary story as likely. But I find this very intriguing and it does seem possible to me that the capacity for throwing gave rise to the capacity for language.

physically sin a message to another species via projectile. But then eventually that begins to get into this way to manipulate their behavior at range, especially in the case of power scavenging, and ultimately it could be used as a

way to hunt prey animals. Right, And as we were actually recording that episode, my mind kept turning to these images of some sort of prehistoric warfare scenario in which some you know, entirely too kubricky prehistoric people were employing various weapons and kind of probably also probably a slightly two table top war game manner where you have you know, units of bone wielding beaters moving forward to engage in some melee attacks, and then maybe you have some units

of rock throwers behind them, and you know this this felt kind of silly in my head, maybe even a little Gary Larson esque in my head, a little farside. But then I started looking into it more because, of course, you know, rock throwers were an important part of our history, and when you start looking at into the history of not only range weaponry, but hand range weaponry, it gets pretty fascinating.

multiple assailants even more dangerous. And of course we see this reflected in the use of stoning as a form of execution from ancient times through modern times. But I didn't want to dwell so much on that because that's more depressing subject matter. But I wanted to focus more on hand thrown stones and weapons in a hunting and warfare context. Okay, So I think for many of us, and this was me until just the other day, we tend to think of ranged weapons as this steady ascent

out of the Stone Age. So sure we threw stones at things then, and we greatly increased our ability to strategically employ those thrown stones, But then we got why, and then of coach, we probably got wiser about how we selected stones, granted, But then eventually we're gonna level up, right, You're gonna upgrade to using something like a sling, a spear, a spear thrower, a bow and arrow across bow, et cetera,

all the way up through the modern era. And I think it's easy to think of this as a linear progression, or like a video game skill tree, a situation where you could you're yelling at the screen, Hey, don't equip the throwing rock, you fool. You have a spear, Now equip the spear.

martial arts. The first thing I ran across was an interesting mention in the Coming of the Mallori Weapons, a nineteen forty nine text by New Zealand anthropologists and doctor Tae Rangi Heroa who lived eighteen seventy seven through nineteen fifty one, in discussing the prevalence for spears and clubs in Polynesian history. He also discusses the swing as a primary range weapon along with the spear, and then he

shares the following quote. Stones were also thrown by hand, and early European voyagers have reported this form of attack more than the use of the sling. The bow and arrow, while present in some groups, was used for sport but not as a weapon of war. In Samoa it was used to shoot pigeons, in Hawaii to shoot rats, and in the Society Islands it was a chiefly sport in which archers clad in special costume shot for distance from

raised stone platforms. Now, obviously this is an older source here, but instantly reading this he realized, well, this is true. It raises interesting possibilities about the dependability of thrown stones as weaponry even as other technologies come online.

not all hunter gatherers use the bow and arrow. He mentions Australian Aborigines as an example of a people who did not, despite some of them surely being aware of the technology via contact with the Tarres Strait Islanders who used bows. They were still people that retain the use of ranged weaponry that depended on hand thrown objects, and will come back to the most famous classification of hand thrown objects that they used in a bit. But where I really got fascinated with all of this was a

paper from twenty eleven. This was published in the Journal of the Polynesian Society by Barbara Isaac and Grenaria Isaac titled Unexpected Trajectories, a History of New Wayan Throwing Stones. The authors here describe the warstones of New Way. New Way is an island that's fifteen hundred miles or twenty four hundred kilometers northeast of New Zealand, and when Captain

James Cook visited the island in seventeen seventy four. He dubbed it the Savage Island, which may have had something to do with their consumption of the native banana species, which to understand had like a red peal and an orangeish interior, and if in the teeth or rubbed on the body, might look like blood. This also clearly reflects Cook's general attitude towards indigenous peoples as well. But he also certainly seemed to have encountered some difficulty in landing

on New Way. It's apparently difficult to land on the island anyway due to the surrounding coral reefs, but the people of New Way were also hostile to his landing attempts and his naturalists. The naturalist on this particular voyage, Andrews Sparman, was injured by a thrown stone. I believe it got him in the arm. The New Way here they were not just picking up random stones and throwing them either. This is where it gets really fascinating. They had a highly refined approach to the use of hand

thrown ranged stone weaponry. According to Isaac and Isaac, the warriors were reported at the time to each have spears on their person, to have a swing and also have a pouch of stones for throwing. But throwing stones and sling launch stones were not uncommon among other people who were encountered on islands from this vast region, so comparatively,

there wasn't much Western commentary on these throwing stones. But the throwing stones of New Way, according to Isaac and Isaac, were quite singular, and much of it would come out later through indigenous recollections, the work of later anthropologists and missionaries, as well as later analysis of stones that were subsequently taken off the island after Western contact.

that are harvested. They tended to weigh around three to four pounds each and they were largely spherical in shape. They were often compared to small cannon balls by Western commentators, but the difference is that they were elongated a little bit on the two opposing ends. You can look up pictures of these online and to me, if I was to compare them to a naturally occurring object, I would say they kind of look like like well crafted stone, lemons or limes.

indication of thought and design natural to this people. For it is not probable that the first inhabitants brought the ideas with them. But they found this limestone in the caves, saw the use to which it might be put, and designed the shape. It is therefore original on their part, and in this particular they anticipated the European science of the recent century. Now they don't note what he was referring to here on the European science thing. I'm thinking

maybe airships. I'm not sure. They kind of have an airship look to him, I guess. Now. On the limestone front, nineteenth and twentieth century anthropologists described other warstones that were sometimes used that might have been made of other materials of basalt of coral, for example. You definitely have examples.

and fish were hunted with nets. So these were exclusively

for dealing with human threats or perceived human threats. Warriors would carry them in bags or on belts, and if they ran out of ammo, it's mentioned that they would naturally make use of stones from the ground as well, so they weren't above you know, reaching down and grabbing whatever was available and throwing that after your special stones were extinguished, and then of course after a skirmish or battle, you would hopefully be able to go back and pick

up your AMMO retrieve them. Because other sources mentioned that they often they had names, they had histories, histories of violence, and so these particular stones would kind of resonate with importance to the individual who wielded it.

four fathoms in length. The third night before the war arrived, they wound the kafa around their stomachs and slept in

this manner during the night, neither eating or drinking. So in this paper, the authors here they point out that these new weeg In stones, these war stones, there were songs about them, and part of their importance also may have had to do with the fact that they were products of the caves, which were sacred sites with seems like connections to the afterlife, And of course this matches up with the way caves were viewed by peoples and

other parts of the world as well. The stones were used in ambush attacks, in skirmishes, but also sometimes in fights to the death would occur, but it seems like a lot of these battles, based on some of the commentaries, may not have been typically that lethal. So yeah, this does line up with this idea of communication. It's not necessarily about going out and absolutely murdering the competition, but driving them away from resources that you're looking to control.

And in the paper, the authors also mostly speculate on accuracy here, and part of this was based on accounts of other throwing techniques by other advanced stone or club throwing groups, but they speculate that high accuracy was likely within twenty yards or eighteen meters roughly, but greater distance accuracy was certainly possible. And I think this makes sense when you consider the likely scenarios in which these stones

are being used. So yeah, any kind of sort of tabletop gaming scenario that you have in your mind should probably set aside. It sounds like most of these the the encounters these battles would have involved like one individual against one another individual or one small group against another. It seems like skirmishes and small ambushes were sort of the typical encounter context for their usage. So anyway, it's a fascinating paper. It's available on jay Store if anyone

wants to read more. They really get in depth about the history of it and various mostly Western commentators who are looking at it, and also how the use of the stones was disappeared and then the stones went out throughout the world and then were to certain degrees brought back or studied. Now, this was certainly the most to me anyway remarkable account of stone throwing I came across,

but not the only account of specialized throwing stones. I ran across the work of Guy Steibel talking about archaeology finds in Jerusalem and the accumulated weapons and AMMO that they were finding. This was a paper that came out on twenty thirteen.

Quote three flint balls have a single flat face, unlike weights or grinding stones that frequently exhibit multiple flat surfaces. They were ideal for heaping on top of battlements, as modern experiments have demonstrated. In light of parallels from both Palestine and the Roman West, it appears that the use of hand thrown stones was much more prevalent than had been previously appreciated in modern scholarship.

a bow. You can just drop things on people underneath. And it was dropping things on your besiegers was a favorite tactic. Be that you could drop rock, you could drop various burning things, oils, et cetera, all manner of things, and again with lethal intensity. But this idea of not just having stones, but stones that had been to some degree altered or manufactured or crafted in order to just stack up there so they're ready to go, but they're also not rolling out of sight and posing a danger

to anyone who might just say, be working beneath. Now, there are also several interesting cases, probably many many more on top of what I'm going to highlight here of hand thrown clubs and throwing sticks. So you know, we've been talking about throwing rocks, but of course throwing sticks is just sort of the other side of the equation here, and you find example of these traditions just throughout the

world on various continents. The throwing stick was used as a hunting tool by prehistoric peoples, and we have examples of these going back at least some three hundred thousand years.

One of the problems that this is something that's pointed out in a paper I was looking at by Conrad at All in nature, ecology and evolution, is that a throwing stick is generally a wooden stick, and therefore it's not always going to survive to become an artifact that can be studied and interpreted, you know, hundreds of thousands of years later. But the practice of hunting with thrown

sticks certainly survived. The ancient Egyptians retained a practice of hunting with throwing sticks, and we see this commemorated both in their hieroglyphics but also in art. I included an image for you to look at here, Joe, where you see an individual clearly out by the water side. There are all these birds around and in one hand the individual was holding up this throwing stick.

Fiji Islanders used beautiful and ceremonial throwing war clubs. These were called ulahs, and you can look up examples of these. Some key African traditions of throwing clubs are notable as well, including the East African rungu as well as the knob carry of southern and Eastern Africa. And these were used for hunting in war, but also became highly symbolic social

signifiers as well. Yeah, but I feel like the idea that the thrown blunt weapon the throwing club is something that is often I guess glossed over in at least in the Western mindset, you know, just again coming back as always to things like Dungeons and Dragons, where we wrap all these fantasy scenarios around the use of ranged

in melee weaponry. It's easy to dismiss the idea that, yeah, that the club also is a potential range weapon, though of course, I think Dungeons and Dragons does at least have a boomerang in it, And the boomerang is probably the most famous, and I guess the most exceptional of the throne clubs that humans have developed over the ages.

The boomerang is exceptional because it's still essentially a throne club that kills or injures via blunt force, but it is also crafted to spin in just the right way and by virtue of its shape, to generate an aerofoil, which then increases the distance that it can be thrown. So it's not only you know, throne but it also begins to take on flight in a fascinating manner.

and their non returning boomerangs. Non returning boomerangs were primarily weapons, while returning boomerangs were I think more in the recreational and symbolic and mythological sphere of things, but could also be used apparently in hunting scenarios as some sort of decoy for I think, birds of prey, but also as a means of frightening and tended bird prey, So they

weren't without functional uses. And there are a lot of things similar to these boomerangs that we find in other cultures as well, like the Tamil people had a kind of non returning boomerang of their own called a valari, and you can look up various images of this as well. Has a slight boomerang shape, kind of a tusk like shape. Now going back to Thomas Coulett here, he points out that broadly speaking, the evolution of range weaponry was initially an evolution that had a lot to do with range.

Thrown weapons greatly increase the range at which human beings may inflict harm. But then additional throwing technologies extend that range, and this of course increases what we can do with them from a hunting standpoint, but also provides advantages over other human adversaries, at least under the right conditions. But I think these examples show that it's not just a

matter of abandoning the use of hand thrown projectiles. We retain the physical abilities as well as the basic skill sets, and we see this reflected in our sports as well as our weapon cultures. Hand thrown weapon traditions clearly survived the advent of other range weapon technologies and in many cases retained important cultural values as well. And there's one final wrinkle here too that I almost completely blanked on. I almost didn't have anything about this in the notes,

but then I of course remembered well. As we enter into the age of explosives, hand thrown weaponry remains important in the form of hand grenades. The more common variety of grenade is of course made to be thrown by hand, much like a throwing stone, more or less fits in the human palm, though we also have the example of the German stick hand grenade that was used in the first and Second World Wars, and I think adopted by

some other groups as well during this period. But as the name implies, this design features a long handle, and these were thrown end over end, much like a hunting stick or a thrown club. Now, in both cases, obviously, given that this is an item that will explode, you don't necessarily have to be as precise. It's not a situation where you have to hit somebody in the head with it or in the neck with it every time

for the weapon to be successful. Though I guess there would be situations where you were trying to throw said grenade into say a window or some sort of an opening and a tank, etc.

so I guess there is maybe a potential lag. There's this kind of gap between the high age of stone throwing and stick throwing as a viable weapon, and then the emergence of explosives, which kind of reignites the need to be able to throw precisely or at least with some degree of precision. You don't want to throw a hand grenade imprecisely, but we certainly see with hand grenades that like the need for individuals to throw these things

becomes all the more important. I mean, you look at images of say, modern soldiers training to throw hand grenades, and there's a definite form to how you do it, you know, like there's definite training in place, so precise throwing of handheld objects remains a seemingly important part of the modern military scenario.

don't know. I guess it felt like one step manufacturing or materially away from just throwing a stick or throwing a rock, So I didn't get into that, But obviously there's a lot one could additionally discuss involving hand thrown axes, hand thrown darts and knives and so forth. So I guess different aerodynamic properties come into play with at least

some of those weapon designs. All right, we're gonna go ahead and end it there, but we'd love to hear from everyone out there if you have thoughts, feedback, experience on anything we've discussed here in this episode or the previous episodes regarding animals throwing things, humans throwing things, the role that being able to throw something may have in the development of language, and also just the various weapons

cultures martial arts that have involved hand thrown objects. If you have anything to add about any of that, please write in we would love to hear from you. Just a reminder that Stuff to Blow Your Mind is a science podcast with core episodes publishing on Tuesdays and Thursdays. On Mondays we do a listener mail and that's where you can write in and we'll discuss some of the

mail that comes in. On Wednesdays we do a short form artifact or monster fact episode, and then on Fridays we set aside most serious concerns to just talk about a strange film on Weird House Cinema.