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A book by
William H. Calvin
The Throwing Madonna
Essays on the Brain
Copyright 1983, 1991 by William H. Calvin.

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Scanned, OCR'ed, and webbed -- but NOT proofread (14 Jan 97)


Did Throwing Stones Lead to Bigger Brains?

Modern evolutionists concentrate on what they can see and measure. This is good, but only up to a point. Some components of evolution that cannot yet be measured have probably been important too, and throwing may be one of them.
PHILIP J. DARLINGTON, JR, Evolution for Naturalists, 1980

What is now proved was once only imagined.


Friday Harbor Laboratories
San Juan Island, Washington

Lying on the beach and throwing stones at a log seems a natural sequel to a really low tide. Low tides mean hopping from one slippery rock to another as the waves gently lap the exposed seaweed, then bending over and peering under the rocks in search of intertidal creatures. Such unaccustomed exertion in the fresh salt air is best followed by finding a sandy stretch of beach and settling down with binoculars, or a good book, or a good pillow. For a break, throw a stone at a log.
      The knot in the driftwood log makes a good target. Throwing stones is such an unexpected pleasure. It brings back memories of three children having a contest to see who will be the frost to topple a pile of flat stones placed atop a distant log. And it isn't just children (and similarly playful types such as scientists) who like to throw rocks at targets. What is it that makes slinging a stone such an elementary pleasure? It almost seems in a class with responding to a baby's smile, or taking pride in one's handiwork -- as if it were one of those built-in human reinforcers. A pleasure that happens to have survival value for the species.
      That seems to be one of the things that have changed in recent evolution: while young monkeys playing together romp unmistakably like children, no one ever sees monkeys lobbing rocks at a log and cheering one another on. They do use projectiles: monkeys have been observed to drop coconuts from trees to crack them open. But then birds do that too, breaking open snail shells rather than coconuts.
      Chimps come a bit closer to humans in aiming and throwing things, as they have the same brachiator's shoulder joints that we do. They have been observed using both arms overhead to throw a stone down at the head of a dead monkey, trying to break open the skull. Also in aid of extracting a delicacy food (were brains the original piece de resistance?). But there is a big difference in accuracy and range between braining a stationary target and exhibiting the skills of a Little League pitcher.
      Actually, it isn't just late-afternoon-plus-fresh-air musings that generate all this fascination with throwing things. There is a good chance that the origins of language, no less, might be intimately tied up with the evolution of such throwing skills.
      What? Is this an academic justification for the importance of baseball? Is he an athlete about to propose that the progenitor of talking man was a star pitcher? To allay any fears, let me assure you that I have impeccable credentials: I never graduated from the Little League, I haven't watched a baseball game in twenty years, I don't even know whether the Yankees are still in New York City. And someone else usually knocks the stones off the log before I do. Honest. But I suspect that pitching and talking did have something important in common, not recently but back a few million years ago.
      It probably all started with the invention of one-armed rock throwing, handy for hunting prey without the usual long chase scene. Throwing possibly promoted the first important lateralization of a function to the left brain, an ability to rapidly orchestrate muscles in novel sequences. And I'll bet that this muscle-sequencing lateralization, most noticeable these days as handedness, was what started up not only toolmaking but language.

Where to begin? A boat drones by on a backdrop of sea haze. A seagull struts across the sand. Binoculars reveal a bald eagle perched in a distant tree, surveying its domain. The rabbits are out sampling the grass nearby.
      Rabbits. Strange as it may seem for beginning a discussion of language (or, for that matter, throwing), consider a dog chasing a rabbit. One often sees a dog trying his best to head off a rabbit in a spirited zigzag chase. Since the domesticated dog does not have quite the motivation or the practice of his wild canine counterparts, the chase usually ends with the rabbit disappearing down a hole. Though sometimes, at least on this island, the rabbit is intercepted by an opportunistic eagle, to the dog's horror.
      But the chase is the thing. And since it isn't taking place on a smooth racetrack, both hound and hare have a problem. There they are, running fast on all fours, but they cannot pick their way across the irregular terrain like barefooted bathers, deciding where to place each foot. No, they can only look ahead at where they'll be a second later and correct their more automatic four-legged gait away from the nearby tree or the imminent pothole. Essentially, they have to project their present position ahead in time, just as an astronaut computes the trajectory of a spacecraft.
      And they do it well. Even when the rabbit tries veering sharply to one side, the dog often cuts the corner to head him off, instead of following the rabbit's path. It's like the sheep dog's maneuver of trying to get in front of the straying animal. The dog is not only protecting himself ahead in time and space, but he is in effect "computing" the prey's trajectory as well--just as the astronaut computes the moon's orbital path and arranges things so that spacecraft and moon arrive at the same place at the same time.
      But the dog and the astronaut both can make little last minute corrections. If the dog doesn't turn as sharply as the sheep or the rabbit, he can perhaps correct this later. And the astronaut can engage in a little mid-course correction. Not as good as doing it right the first time, but fix-up-able.
      Throwing rocks is a different matter--no mid-course corrections are possible, unless you've got one of those wire-guided antitank missiles that an infantryman can steer toward the target after firing. But despite this shortcoming, throwing rocks has its distinct advantages over chasing a rabbit. It's faster and uses up less energy than a chase. But how did throwing rocks ever evolve from the usual prey-predator chase? If we are not to be Panglossian about things, what were the intermediate steps, and how did evolution come to reward them?
      Actually, maybe throwing didn't evolve out of the chase. Or even out of hunting. Think back to that chimp, trying to brain that dead monkey. Suppose the monkey wasn't dead: braining it would make it safe for eating. One doesn't want to get too close to a wounded animal thrashing around--one might get hurt, and that's a no-no for evolutionary fitness.
      So keeping a safe distance away and throwing stones at its head would have been a useful practice, keeping oneself healthy and one's offspring fed. Just move stone throwing up to the beginning, rather than waiting for dessert time. And the next logical step is to throw the rock in the first place, before the prey has already been brought down by other means.
      But throwing a big rock overhead with both hands, while forceful, does not allow for much range. It would have to be a stupid or sick rabbit to allow someone to get close enough for a two-handed overhead throw. The way to get range is to throw a smaller rock with one hand. Uncocking the elbow, the way one does in throwing a dart, is the most important part of throwing: it's a sling, nature's version of the one David used on Goliath. But you've got to release the rock at just the right time.
      (Want to know the physics behind why pitching is better? First of all, as the army discovered belatedly, bigger isn't always better. High velocity is better than massive weight--so the current M-16 army rifle now uses a small .22-caliber bullet but with lots of powder behind it. It's the kinetic energy packed by the projectile that does the damage--and while it is proportional to weight, it's also proportional to the square of the velocity. Thus the trick for throwing is to get a lot of velocity behind a smaller stone. There's a ninefold improvement when you triple the speed. But never mind--surely the hominid didn't understand the physics either, but still invented pitching.)
      The hominid that started pitching stones would have a considerable advantage. It could now prey on animals that were faster than it could run. And what animal runs faster than a good fast ball? The hominid could also avoid mixing it up with a prey, with all the attendant dangers of getting killed or maimed in the process. Lions do get gored occasionally by those wildebeest horns and elephant tusks. And throwing allowed larger prey to be taken on.
      Action at a distance. One of the better inventions of biological evolution since sex. I don't mean to suggest that humans evolved out of an impatient chimp trying to eat brains for an appetizer rather than waiting for dessert time, but it does illustrate one possible path of inventions that could have led to throwing, and from that to a whole new set of possible prey in varied habitats.
      But while this might be relevant to the origins of hominid hunting, whatever has it to do with language? Think back a few million years, to one of those walking-upright prehumans whose brains were one-third the size of ours. What set the stage for that rapid growth of the brain since the Pliocene? A rapid growth and remodeling which gave rise to a language specialization occupying a prominent chunk of the left hemisphere, and to parietal lobes which grew a lot beyond those of the chimpanzee. How did brain size lead to, or result from, such enhanced functions?
      This may seem like a chicken-and-egg, which-came-first question. But such rapid change is, by itself, highly suggestive of the rapid exploitation of a new resource, or perhaps a new feature of the brain that led to a more-than-modest success in feeding oneself and one's offspring. Or perhaps brain evolution acquired a two-for-the-price-of-one mechanism, the way the two-pants-suit doubled the longevity of the suit jacket.
      Maybe that new feature was not language per se but lateralization: avoiding the duplication of a function, just concentrating it in one hemisphere. While language skills might have been helpful for survival, maybe they were just a side effect of the lateralization of some other skill having more direct survival and reproduction benefits. Like maybe throwing.
      Like maybe something else, too. Other than the nice supply of egg-size rocks on the beach, why pick throwing? Because sequential-movement skills, like language, seem lateralized to the left hemisphere. Language is "lateralized" to the left brain in the sense that for every fourteen people who suffer language impairment, thirteen will have left-brain damage and only one will have a right-brain problem. Such 13: 1 odds are not matched by any other lateralized function. Visual-spatial skills are the specialization usually said to live in the areas of the right brain where language lives on the left. Damage to the right brain results in problems with getting dressed, or reassembling a flashlight when changing batteries, or reading a map. But spatial skills are impaired only two to five times as often by right-brain damage as by left-brain damage. So they are not lateralized as strongly as language.
      Yet neither language nor spatial skills are notably lateralized in chimps; although some suggestions are beginning to appear, it is the ratio that matters. Something must have gotten such lateralizations started, something useful at the time. Something exposed to natural selection pressures.
      So what is this about sequential-movement skills also being lateralized to the left brain? It was discovered that patients with left-hemisphere strokes had trouble fitting keys into locks, unlatching chains, and then turning doorknobs. With either hand. They could do each action separately, but doing them in the proper sequence was a problem. Right-hemisphere strokes don't usually create such problems. Doreen Kimura, a Canadian neuropsychologist, found it fascinating that such sequential-movement skills went along with the language skills of the left hemisphere-- patients who were aphasic also might have difficulty using either hand for such tasks.
      And then one of her doctoral students, Catherine Mateer, showed that aphasic patients also had analogous difficulties with facial movements. Again, the face was not paralyzed. Shown a color slide of Katy sticking out her tongue, the patient could mimic the action. But shown a three-part slide of Katy first sticking out her tongue, then pursuing her lips, and finally grinning, the patient couldn't act out the sequence in the correct order without making frequent mistakes.
      So the left hemisphere seems to have a specialization for muscle sequencing, not only for hand movements but for oral facial movements as well. Very interesting. Might that have something to do with language? Just because both skills are in the left hemisphere doesn't mean they are intimately related.
      But in fact they are: The core of the human left language cortex is an area specializing in oral-facial sequencing. Catherine Mateer went on to Seattle to work with my colleague George Ojemann, using electrical stimulation of the surface of the human language cortex to test patients during epilepsy operations under local anesthesia. They discovered a wide area, just above and below the Sylvian fissure, where stimulation temporarily disrupts the patient's ability to mimic the facial sequences. And the very same area also serves to help the patient recognize the individual sounds that make up speech, the phonemes. Surrounding this area is a patchwork of specialized regions for semantics, syntax, and short-term memory for words. But that is another story (and is recounted in Chapter 16).
      Maybe the sequencing lateralization is why language and right-handedness usually occupy the same left hemisphere. After all, what is handedness? It isn't fine movement control that distinguishes the good hand from the other. It is the skill in ballistic movements such as hammering. And throwing.
If movement sequencing is, literally, the core around which the rest of language is built, it raises a very interesting question, as Kimura, Mateer, and Ojemann have recognized: Which came first to the left brain, sequencing or language? Maybe the first lateralization wasn't language but rapid movement sequencing . . . ?
      Back to throwing rocks at a log on the beach of San Juan Island. Knowing that my overhand throw is far more accurate than that of other apes, and that my muscles are being orchestrated by a sequencing specialization which resides in my left brain, I begin to wonder if the progenitor of talking man really was a right-handed star pitcher. Maybe it was throwing rocks at prey that got the brain started on the road to lateralization and language. So maybe that's why throwing is so important to human evolution: advanced pitching is distinctly a one-handed operation.
      Unlike locomotion or the chimp's two-handed over-the-head throw, pitching requires using one side of the brain far more than the other during windup and throw. Any chance tendency for one hemisphere to be better than the other at rapidly orchestrating muscle sequences could make the animal better at throwing with the opposite hand. So pitching could have resulted in a strong selective pressure to permanently establish any lateralization tendencies for muscle sequencing that the genome might have randomly tried out (and, as noted in Chapter 1, maternal throwing success might have made that often than the right side).
      But why this emphasis on throwing? Surely toolmaking would have rewarded lateralization, surely social cohesion would have rewarded language, surely there are many factors? All true, but the issue here is what got lateralization started, not its subsequent elaboration. Throwing has the advantage that it is one-sided, that it stresses the system for speed in a way that toolmaking doesn't, and that it has a really major payoff--an immediate one, promoting the survival of your own offspring, not just some advantages later.
Missed again. I get up and try stacking three piles of flat rocks atop the log, then retreat back to my comfortable seat, picking up missiles along the way. Ten straight misses, then a hit. Funny how you can tell a good one even before the rock leaves your hand. Of course, after it leaves your hand, it's too late to change anything--you have to make all of the corrections during the throw, not continually during the chase as the dog can do. So my brain has to compute, in effect, the trajectory of the rock and arrange the arc through the air so that it will come down on the target. Not bad.
      But not too different (except for being compressed into a brief moment) from what the running hound and hare are doing projecting themselves ahead in time and space, arranging it so that their feet do not insert into an approaching gopher hole. But there's nothing predominantly one-sided in locomotion, nothing to ~reward" lateralization the way that throwing could have done by providing more survivors who carried its genes. Nor is projecting the prey's trajectory, when cutting corners during a chase, inherently one-sided. But maybe during throwing....
      Suppose I was throwing the rock at a moving target, as in one of those amusement arcades that dispense symbolic stuffed rabbits. Our ancestors weren't always throwing rocks at dead monkey skulls. Indeed, they probably developed a taste for rabbit and similar swift small animals. Rabbits are used to being chased. They worry about rapidly moving animals on the ground. They are also used to worrying about birds swooping down out of the sky. But they aren't used to having rocks thrown at them. Or at least the rabbits and hamsters of a few million years ago weren't, back before man became the first action-at-a-distance predator.
      Just move very slowly until you get into throwing range, as close as your experience tells you the animal will tolerate. Then cock your elbow behind you, so that your body blocks the animal's view of the first half of your throwing motion. When he does startle from seeing the rapid throwing movement, it may be too late it only takes about a half second for the stone to reach most targets, and he can't move very far in that time. The object is merely to stun the animal, to foul up his escape long enough for you to grab him.
      And the faster you can throw, the better. Not just to decrease the chance of the animal moving in the meantime. Faster is lots better. It means you can throw farther. And it means more stopping power. So that you can stun bigger animals, maybe bush pigs rather than just rabbits.
      So faster is better. But much more diff~cult for the poor brain. The launch window for your missile is already narrow. To hit a rabbit from a car length away, you need to let go of the rock within a time equal to the time the shutter of a camera stays open when set at 1/200 second. And if the rabbit is twice as far away, your launch window shrinks eightfold. There aren't too many cameras around that operate at 1/1600 second. But your brain can time things that precisely, letting the rock slip at just the right fraction of a millisecond, over a throwing time of many hundreds of milliseconds. Somehow. It has to, if you can hit such a target. So saith Newtonian physics.
      That's the sort of problem that motivates computer scientists to build bigger and better computers. But the human brain was getting bigger: if any random tendency in that direction resulted in better hunting, natural selection might have conserved those larger-brain genes, giving them a chance to try again.
Two targets down, one to go. At least children wasting an afternoon, throwing rocks at a log, would never bother trying to justify it. But now this throwing theory has a life of its own. It even makes the opposable thumb critically important--that's what lets the rock slip at just the right instant.
      But while faster is better, is a bigger brain faster? A faster throw requires more precise timing, bringing in each muscle at just the right instant with an orchestra conductor's split-second timing. Neurons are notably noisy things and great precision is not their forte. But more are better. Heart cells in isolation will beat, but somewhat irregularly. Clump a few together, and they'll exchange currents so as to all beat together--and the beat will be more regular. Forty cells linked together are even more rhythmic, ticking along like a clock. The timing precision depends on the square root of the number of cells, something called the Law of Large Numbers.
      A similar problem arose when analyzing the circadian rhythm of the sand flea: how did they manage to restart their internal clock within ten minutes of exactly twenty-four hours? No individual neuron is that accurate, being more like sixty minutes off. But a simple circuit of many redundant neurons, all doing the same job, is much more accurate because it averages the output of the many neurons. Four times the number of neurons will reduce the fluctuations by half. Thus one simple way to make a neural circuit much more precise is to duplicate it over and over, dozens of times. Bigger is faster, and faster is better, as we noted before. Hence bigger brains are better?
      Not bad. Now, if only I could just manage to reset the rhythms of all these local sand fleas, to make them think it was really the middle of the night rather than feeding time.
      You know -- oops, time to gather up more rocks -- this might solve one problem which has plagued evolutionary theory. Sure, language is a good thing, but just how did it provide enough survival advantage to make all of those changes step-by-step? That's the trouble with adaptation stories. Fertile (or febrile) minds can always come up with a rationale for why something was useful or harmful. But was it exposed to selection pressures? Talking on the telephone can be a survival skill in rare instances--but riding motorcycles really exposes one to natural selection (negatively, judging from the severe head injuries seen in our emergency rooms). Granted, language might have helped a band of hunters coordinate the capture of a woolly mammoth, but what rewarded the gradual steps which preceded that stage of speech? Little improvements in survival skills, or an important jump into an unfilled ecological niche?
      It is easy to see how such throwing improvements in hunting technique might have conferred an immediate selective advantage, perhaps of "new ecological niche" proportions. If our ancestors were anything like chimps, they lived in the tropics, gathering fruit and cracking nuts, grabbing some occasional meat--a way of life which doesn't work well outside the tropics.
      But suppose they invented a way of regularly, reliably eating small mammals and birds? Unlike fruit trees, that source of food is widespread, all over the earth, on the plains as well as in the woods, in colder climates as well as in the tropics. Hominids could have expanded their population to occupy new habitats. And then have gotten overextended, so that small groups were isolated by climatic changes and subjected to the environmental stresses which, in a small inbreeding population, may lead to a new species.
      Predators-at-a-distance would be a new gimmick on the ecological scene, conferring a new niche. The traditional reward for the species that discovers a new niche is a population explosion. Just imagine the population explosion that will occur in the bacterial species that first learns how to digest nylon. First it will colonize the trash dumps and the used-car lots, then take over the shopping plazas....
      But there's also the two-pants-suit gimmick. Improved throwing skills would be a reward for the left-hemisphere skills-- but surely the right half would be enlarged symmetrically at the same time. That enlargement would have gotten a free ride on the left hemisphere's accomplishment. The right-sided space corresponding to that occupied by the left-sided muscle sequencer would be sitting there, like an unfinished basement, just waiting to be put to good use.
      That's two for the price of one. If the right brain found a visual-spatial use for the extra space, say improved depth perception, it might have again improved hunting--further reinforcing those bigger-brain gene combinations, and thus housing muscle sequencing in bigger quarters during the next round.
      Another nice ratchet for evolution: Selective pressures that reinforce sequencing improvements in throwing also could provide extra space for visual-spatial, and vice versa. Thanks to lateralization, improvements go twice as fast? So perhaps the lateralization of throwing was what started the rapid enlargement of the brain. And perhaps "throwing genes" are little more than bigger-brain genes.
Undoubtedly humans are the outgrowth of a whole series of selective pressures which forced our predecessors to learn to eat new foods, live in new habitats, develop new reproductive strategies such as kinship. Each Ice Age has probably left behind a residue of skills which, like the boulders scattered across the landscape, remain after the vicissitudes have vanished. The generalized animal developed out of leftover specializations, just as the general-purpose computer developed out of such leftover special-purpose computers as the player piano and control systems for antiaircraft guns.
      So, did generalized human language evolve from specialized hunting "computational" skills? Bootstrapping language through better throwing? If oral-facial sequencing built upon the throwing-sequencing machinery of the left brain, then it would be natural for the expanding repertoire of verbal expressions to also settle alongside in the left brain--and so to set the stage for more sophisticated language, hence culture, and science, and all the rest.
      Is language, that sine qua non of humankind, merely a side effect of braining rabbits? Well, is that worse than its being an offshoot of the vocalizations used for threats and warning cries? Those species-specific vocalizations in monkeys might, of course, also have served as the scaffolding upon which language was built. Certainly they are a more obvious choice than throwing.
      But that seemingly logical proposition has one problem: the cortical specializations for those vocalizations in monkeys are not located anywhere near the Sylvian fissure, around which the human language area has come to reside. They are far away, near the midline of the brain, just in front of the motor area for the foot and just above the corpus callosum.
      So perhaps language was built on the scaffolding of sequencing rather than snarls. From gestures to grammar.... Suppose that's why chimps are better at sign language than spoken language? Or why modern human males, who are often more natural pitchers, have language more strongly lateralized than modern females (though this is hardly to be envied: males are far more likely than females to suffer aphasia after a left-hemisphere stroke).
Finally! It felt right, and a second later, the rock knocked the last target off the top of the log. Well, not a bad afternoon's reverie.
      So the key problem is a fast track for hominid evolution, whether throwing could have enlarged the brain faster than intelligence. Lateralization too is likely to lead to bigger brains, simply because of creating extra space opposite a successful specialization, the two-for-the-price-of-one ratchet.
      Of all the known lateralizations, sequential muscle control seems the most central to the others, such as language. And what could have resulted in sequential muscle control residing primarily on one side of the brain? Well, an important muscle sequence involving primarily the opposite side of the body, rather than both sides equally or alternately. Say, handwriting or throwing or grooming or tool use. Surely handwriting wasn't the first. And no one has ever discovered a cortical specialization for grooming.
      But what selective pressures conserved those useful gene combinations for sequencer lateralization and bigger brains, so that there would be even more in the next generation?
      Throwing has big advantages over the other candidates. First, the "new niche effect": an immediate and fairly dramatic payoff in improved life-style, enabling new prey to be eaten with minimal risk, and the consequent ability of the species to expand into new habitats such as plains with lots of rabbits but no fruit trees.
      Second is the "fast ball effect": the muscle sequencer should have had a tendency to operate faster and faster. That's because higher-velocity projectiles would result in greater throwing range, better stopping power, and less time for the prey to react to the approaching rock. But once a short computation time becomes important--and more efficient hunting selects for it-- you need some very fancy timing circuits. Maybe the brain reorganized itself to provide it, or maybe bigger brains in the next generation survived better.
      The other candidates for an earliest lateralization--including language itself--have only slow, indirect, often delayed effects on survivability and habitat, nothing to compete with the exposure to selection pressures which throwing has via the new niche and fast ball effects. And third, since throwing improvements could come from either left-sided sequencer or right-sided visual-spatial accomplishments, throwing would maximally utilize the two-for the-price-of-one ratchet by driving it from either side.
      If it all started with throwing, what were the following steps? Elaborating a hand-arm sequencer into an oral-facial sequencer could have come next. That should have been easy--borrow from thy neighbor. Remember the map of the body's muscles in motor strip, and how close the cortical neurons controlling face muscles are to those for the hand? They're next-door neighbors.
      Then comes language building upon oral-facial sequencing. What selective pressures encouraged that, or did language just get a free ride for a while and settle alongside? -- perhaps in some extra left-sided space, created by the most recent round of ratcheting having been a visual-spatial right-sided improvement in hunting. Surely the gradually increasing communication skills themselves provided a selective advantage for hand gestures and facial expressions, as well as speech.
      Just as improved tool use with the right hand, say for chipping rocks into scrapers and knives, could have resulted from the rapid movement sequencer in the left brain. Again expanding the choice of prey via using sharpened spears, expanding the possible Ice Age habitats via tools to skin animals and sew. And, of course, the sparks that fly while chipping hard rocks were probably the origin of fire on demand. Good old throwing, useful for explaining everything.
      But the capability for handwriting probably got the longest free ride off the throwing lateralization, until it got put to work a mere 5000 years ago. Whereupon the left brain and right hand created a written language, which allowed an accumulation of generation-jumping knowledge, and all that. Throwing strikes again.
      And besides explaining minor things, such as how humans got started and what made book-learning culture possible, the throwing theory even reveals the true origins of baseball, establishes it as the most elegant of all sports, the fast ball as the most fundamental of inventions.... Ouch! Sunburn.... Or is it sunstroke? Some daydream!
      But it's all too much. No one will ever believe it. Except maybe baseball fans.
The Throwing Madonna:
Essays on the Brain
(McGraw-Hill 1983, Bantam 1991) is a group of 17 essays: The Throwing Madonna; The Lovable Cat: Mimicry Strikes Again; Woman the Toolmaker? Did Throwing Stones Lead to Bigger Brains? The Ratchets of Social Evolution; The Computer as Metaphor in Neurobiology; Last Year in Jerusalem; Computing Without Nerve Impulses; Aplysia, the Hare of the Ocean; Left Brain, Right Brain: Science or the New Phrenology? What to Do About Tic Douloureux; The Woodrow Wilson Story; Thinking Clearly About Schizophrenia; Of Cancer Pain, Magic Bullets, and Humor; Linguistics and the Brain's Buffer; Probing Language Cortex: The Second Wave; and The Creation Myth, Updated: A Scenario for Humankind. Note that my throwing theory for language origins (last 3 essays) has nothing to do with the title essay: THE THROWING MADONNA is a parody (involving maternal heartbeat sounds!) on the typically-male theories of handedness.
Many libraries have it (try the OCLC on-line listing, which cryptically shows the libraries that own a copy), and used bookstores may have either the 1983 or the 1991 edition.

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