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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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The Lovable Cat:
Mimicry Strikes Again

My cat may manipulate me psychologically, but he'll never type or play the piano.
STEPHEN JAY GOULD, The Panda's Thumb

Dogs have masters.
Cats have staff.


Our cat is called "Cat," though that might have horrified T. S. Eliot, who said that each cat must have three different names. But at least our previous cat, Macavity, was named after a famous poem from Eliot's Old Possum's Book of Practical Cats, the original cat book. Cat has endeared herself to us, despite her lack of understanding of the human habit of reading (she prefers to sit on one's chest, between eyes and book; our Macavity at least consented to sit on one's shoulder).
      Given an evolutionary turn of mind, one cannot help wondering why cats can be so endearing. Perhaps they are the original Teddy Bear, taking advantage of the softness which human beings display toward human infants? Taking advantage of an emotional response is an old and honorable technique in the animal kingdom, though usually involving "protective mimicry," where predators avoid certain prey because they "taste bad." For example, Henry Bates noted in 1862 that some Brazilian butterflies have adopted the color and markings of poisonous species, but without the poison (rather like posting burglar alarm signs on your windows but not bothering to buy an alarm system). Mimicry is a fascinating trait in nature, demonstrating that natural selection sometimes operates on appearances rather than reality, that it isn't as specific as you might think, that indiscriminate "prejudice" is an important fact of life. All of which provides some clues to how the domestic cat became domesticated.
      T. S. Eliot intoned: "A CAT IS NOT A DOG." One's evolutionary suspicions are not aroused so easily by the domestic dog. After all, dogs can be working animals, the surrogate shepherd or the hauling husky. Cats are sometimes depicted in humor as working animals: I've always liked the story about the cat that ate cheese so that he could breathe down the mouse hole with baited breath. The usefulness of cats is, however, borderline at best. While Cat proudly presents us with shrews, mice, and the occasional bird (usually in the middle of the night), would anyone take the trouble to domesticate a wild cat for such a purpose? However useful farmers may find cats around the barn (and cats were valued for catching rats during the plague years), something else surely was responsible for the domestication of the cat from its wild ancestor, the Kaffir (or Cape) cat, Felis lybica (which still is found on the Mediterranean islands, in North Africa, and even in Indian deserts).
      One suspects that a cat adopts a human in the hopes of being adopted back-and thus fed. Certainly present-day cats play up to humans in a variety of ways. Consider the greeting ceremony. I am not thinking here of our cat's "Here I am, everyone" vocalizations upon entering the house, but of a feline behavior that few people realize is a greeting. It turns out that the characteristic rubbing up against furniture is mostly a greeting to people in the room; it doesn't often occur when a human observer is absent and a TV camera substituted. It is difficult to understand the function of this poorly appreciated greeting. Perhaps it is just another way of attracting attention? (Certainly when the cat rubs against me instead and I trip over it, attracts my attention.) Or is it just a feline superstition? But the cat's lap-loving behavior is more easily understood and may well be the key to their success as a species: it evokes far more than mere attention.
      One has only to observe a human holding a cat to realize what is going on: the pet is evoking the same reactions that a cuddly baby sets off. Their contented responses when cradled set off the same flood of emotion in us. Babies babble and nuzzle, cats purr and rub. Their not-quite-speech vocalizations cause us to respond with smiles and encouragement. They like being handled, and we like handling them. We like seeing them happy. There is something congenitally comfortable about cuddling.

(Cuddliness, defined? There is actually a rather pragmatic medical definition of cuddliness. Part of the neurological examination of a newborn infant is to cradle the baby and watch-and feel-to see if it begins to conform to the shape of the examiner's body, to nestle in. Babies with depressed function of the higher brain centers often fail to mold themselves in this fashion. Just try cradling a wide-eyed, alert cat that wants to be elsewhere: it too will seem hard and unyielding, even if not struggling to get down. Because newborns cannot talk and follow commands, there are few simple ways of testing their cortical functions -- among the others is the response to pacification maneuvers noted in Chapter I-and consistent lack of response on such tests can be a tip-off to the physician that more definitive tests may be in order.)

      Of course, a cat is not a baby. It doesn't even look like one, and babies certainly lack whiskers. So this is not the usual sort of protective mimicry based on appearances. Predatory birds learn to avoid snakes with the characteristic colored bands that adorn the coral snake; the birds presumably think that such snakes "taste bitter." Ingesting venom is almost as bad as getting bitten, so birds without the ability to avoid coral snakes may not reproduce very well. Other snakes with similar markings, poisonous or not, seem to be avoided by the birds as well-so they survive better and produce more little snakes with similar colors. The birds presumably have enough other prey to eat that they haven't made their color prejudice a little more discriminating. This Batesian mimicry is just another elegant example of natural selection, of the survival of those species with a good gimmick or an imperfect predator. Is the cat still another successful mimic, despite the lack of physical resemblance to babies? Using sweetness rather than bitterness? Playing on human psychological propensities rather than physical appearances?
      The evolution of Felis domesticus (also known as Felis catus) tells us something about the evolution of human reinforcers, about what we find sweet and pleasurable, and why. Although "sweet" has a specific meaning when looking at the neurophysiology of the tongue's taste buds, the concept of sweetness extends to other areas beyond food. There is a symbiotic relation between parent and offspring: the infant needs much assistance to survive, and the parent "needs" to propagate its genes. Genes which reinforce this symbiosis are to the benefit of both parties (and hence propagate the genes). Parents who respond to the sight of an infant by picking it up and cradling it are more likely to propagate their genes for doing so. Sweet is more than quick-energy food related to our ancestors' fondness for for trees: it is usually a selfish gene at work in a more global way.
      After all, nurturing an infant is not a universal trait: some species invest nothing in their offspring after birth. They just try for large numbers and leave them to fend for themselves (e.g., many fish and frog species). Other species invest a lot in a few offspring, the so-called "K selection." They had to evolve ties which bind parent and infant together psychologically for appropriate period of time. A gene leading to cooing can interact with a gene leading to cradling, to the benefit of both. Indeed, all of our elementary human pleasures probably have such a background. Anything that is sweet today is a clue to what was go for the species a long time ago.
      But the features which trigger such responses (Konrad Lorenz called them "innate releasing factors") need not be perfect imitation of the original object. While the selection process may have involved a human baby, the trigger feature may simply be anything about the right size which combined cradling and cooing (like the predatory birds and their snake nothing may have made us more discriminating in whom or wh we cuddle). If the cat's purr can substitute for the coo, the cat has lucked in to a good deal. Because it can become the recipient some of the affection usually reserved for babies, it will stand much better chance of receiving food and shelter. Cats with purring genes, or genes leading them to seek being cradled, will survive much better than those without. Over a long period time, wild cats in contact with humans will slowly develop some of those attributes which we humans find sweet, simply because we don't feel as compelled to feed and shelter the ones that are aloof. It probably started with orphaned kittens of Felis lybica being raised by some children playing house.
      This "lap-first" theory says that the cat was domesticated b mimicry of a trigger feature of the parent-infant symbiotic relationship. And what are those trigger features? Certainly not whiskers! But the ethologists studying ducks haven't had to use stuffed ducks -- something the right size and color, and maybe a little fuzzy, will work just fine to set off many behaviors in a real duck (indeed, for some ducks, Konrad Lorenz himself sufficed). For humans, one way to find out would be to use a stuffed animal and then subtract features until the cuddling response is lost. A do-it-yourself ethology assignment: Borrow some well-used stuffed animals with missing eyes, ears, or legs. Get some new versions, so that you have a full range of physical features. Now get a stopwatch and see how long people will hold each stuffed animal before laying it back down and selecting another. Soon you'll have a reasonable idea of the essential trigger features for this kind of sweetness. Alternatively, consult the doll manufacturers. Or the literature: Lorenz noted in 1950 that the animals for which humans feel affection have large eyes, bulging foreheads, chins that tuck in rather than jut out, and a springy elastic consistency -- all characteristic of human infants.
      They say travel is broadening, and this comfortable (cuddly?) view of cat evolution has been challenged by several encounters. The first involved a feral cat, a domestic cat gone wild. The Friday Harbor Labs are on a large nature reserve up in Washington's San Juan Islands near Victoria, British Columbia. The apartments for the researchers are in a sylvan setting: It's really a wonderland, where deer graze outside your window, where the rabbits don't even bother to interrupt mowing the grass when you walk past. At night, there is a parade of raccoons making the rounds of doors where they are likely to get handouts. Some are quite aggressive and will march indoors and stridently demand the food off your dinner table: real masked bandits. Others will hang back timidly.
      One night in the midst of this parade came a most impressive cat. It had the kind of large, bright, all-seeing eyes that one tends to associate with human geniuses. It was quite wild, in the sense that it would not approach humans. There was clearly a working understanding between this feral cat and the raccoons; the cat may have been outnumbered, but one sensed that it had won a few arguments. Now they shared the bounty. But unlike the aggressive raccoons, the cat wouldn't come anywhere near the door. Timid may have described the raccoons that held back, but one would hardly label this cat timid: it lived and breathed intelligent caution. It wasn't skittish; it was crafty and dignified, engaged in a war of wits with two other species simultaneously.
      Was this feral cat acting like the wild predecessor of the domestic cat? Was the cat originally a camp follower, staying on the outskirts of human habitation and living off the garbage pile, gradually becoming tame? Was the lap the final step, rather than the first step? Not quite like wild kittens being raised as infant surrogates.
      Later, during a sabbatical year in Jerusalem, came a massive exposure to "feral cats." The streets there were full of cats raiding garbage cans. And they were quite wary, never investigating an outstretched hand, much less a lap. I rather pride myself on my ability to make friends with any cat, but I was rebuffed every time. But the reason seemed rather clear: children threw rocks at them whenever possible. Adults cursed them-and not just the ones in competition for the same resource, such as the tramps who came around an hour in advance of the garbage truck, searching through the trash cans for anything edible or useful. Everyone seemed to treat cats as a pest, to be driven away.
      Had the symbiotic relationship between cat and man completely broken down? And, since one tends to think of the people there as being a bit closer to the land and the conditions under which the original domestication of the cat might have taken place, what did that say for my pet theory for cat domestication through infant mimicry?
      Might Israeli cats be a different subspecies than the North American cats, since they acted so differently and since no one seemed to treat them as pets? Most of the cats in North America are descendants of ones brought over from England or the Netherlands in the seventeenth century. Maybe, I surmised, the Jerusalem cats were closer to the cats that the Egyptians had worshiped; indeed, some of our earliest knowledge of cats comes from mummified cats dating back to at least 2500 B.C. Over 300,000 mummified cats were found a century ago; the study of their remains might have taught us much about the evolution of Felis lybica into Felis domesticus -- but these feline mummies no longer exist, as 19 tons of their remains were shipped back to England by some entrepreneur to be ground up for fertilizer. Alas. Lacking data, one can always speculate.
      Armed with my tentative theories about Middle Eastern cats, I consulted with an Israeli zoologist. She said that my data base was insufficient for another reason -- that I just hadn't been in an Israeli home yet that had a pet cat. Many Israeli homes turn out to have pet cats. Some of those cats on the streets are indeed strays, but many are also someone's pet. They act entirely differently indoors, just like normal cats, seeking out one's lap. But outdoors, they've learned to run at the sight of people. From which one might conclude that the North American cats have simply been more successful at making friends -- at adopting people, as it were.
      So was it lap-first or lap-last; did people adopt the cat or vice versa? Having had a whole family group of hominid fossils dug up in recent years, perhaps we will just have to hope that a suitably ancient hominid will be found with a cat skeleton cradled in its lap.
      The evolutionary analysis of the domestic dog, Canis familiaris, and the corresponding trigger features in human behaviors will be left as another exercise for the reader. (HINT. Dogs like to follow one around, gaze up admiringly, play catch, romp, be a good pal-all rather like a _____. The fundamental difference between "cat-people' and "dog-lovers" is therefore____________.


      As Harold Morowitz points out, it is axiomatic in the publishing world that essay books don't sell, especially books of science essays. Lewis Thomas's The Lives of a Cell made best-seller status, however, one hopes confounding whoever invents such axioms. The obvious solution is to mimic a successful strategy, just as the cat mimics the baby's strategy for getting attention and affection. Thus one must include an essay mimicking either (1) a cookbook, (2) a sex manual, or (3) a cat book. The perceptive reader of this essay should be able to figure out the reasons for this particular troika leading the nonfiction best-seller lists.
      Mimicking a cookbook might be fattening. Sex manuals require expensive illustrations (whose costs the publishers take out of the author's royalties, perhaps explaining why so few books, of other types, are illustrated).
      But a cat essay only requires contemplating this endearing little monster on my lap who periodically tries walking across the keyboard of the word processor. It's not that I mind the random letters tacked onto my manuscripts -- and there are often a lot, as the keys automatically repeat like a machine gun if held down. But sometimes Cat will instead hold down the backspace-delete key, causing my recent prose to be consumed backward from the end with great rapidity until I snatch her off the keys. I sometimes have to eat my words, but I prefer that the cat and computer not do it for me. In addition to her aforementioned failings regarding reading, Cat apparently doesn't understand writing either -- but she instinctively understands human psychology. I haven't tried her out on a piano yet, but given her typing performance, I suspect Gould is right on all counts.
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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