The Chronicle Review

How the Scientist Got His Ideas

The Granger Collection

Illustration for “How the Rhinoceros Got His Skin,” by Rudyard Kipling, for the first edition of his Just So Stories, published in 1902.
January 03, 2010

For more than a century, Rudyard Kipling's Just So Stories have delighted millions of "children of all ages" with their unique combination of over-the-top, exaggerated portentousness and scrumptious hyper-elocutionary wordplay. The first of these stories, "How the Whale Got His Throat," begins:

IN the sea, once upon a time, O my Best Beloved, there was a Whale, and he ate fishes. He ate the starfish and the garfish, and the crab and the dab, and the plaice and the dace, and the skate and his mate, and the mackereel and the pickereel, and the really truly twirly-whirly eel. All the fishes he could find in all the sea he ate with his mouth—so!

Kipling was the first English-language writer to be awarded a Nobel Prize in Literature—in 1907—although his star has since dimmed somewhat, largely, we suspect, because he was also an avowed militarist, a supporter of British imperialism, even, by most accounts, a racist (albeit one who ended his best-known poem with, "You're a better man than I am, Gunga Din!"). But these days, some of the most frequent and pungent disparagements of Kipling have been delivered not by defenders of political correctness, or even by the gatekeepers of literary greatness, but by, of all people, biologists, for whom "just-so story" has become a phrase of opprobrium.

The Just So Stories (1902) include fanciful accounts of "How the Camel Got His Hump," "How the Rhinoceros Got His Skin," "How the Leopard Got His Spots," and so forth, building, it appears, on the admired tale of how the tiger got his stripes from The Second Jungle Book, published seven years earlier. No one seriously thinks that the camel got his hump because he refused to work and instead stubbornly proclaimed "Humph," or that a vengeful "Parsee-man" filled the rhinoceros's skin with cake crumbs. It's just that Kipling's stories are so engaging, utterly silly, yet purportedly explanatory, that they have come to mean a delightful but empty fairy tale.

Ever since ethologists, geneticists, and ecologists joined together to create "sociobiology," more recently called "evolutionary psychology" when applied to human beings, practitioners have had to contend with the accusation that their work consists of modern-day just-so stories, imaginative accounts of how the biological world came to its current estate, how the various creatures are connected to each other, and—more controversial, at least for some—how the human species fits in. Efforts to understand the intimate details of Homo sapiens have especially evoked the skeptical rejoinder of "just-so story" when the hypothesized details are conjectures (worse yet, "mere conjectures"), lacking empirical validation. Among evolutionary biologists in particular, that can be a scathing criticism: To call something a "just-so story" is to dismiss it as unscientific moonshine.

And to some extent, the critics have a point. It is easy—too easy, in many cases—to come up with "explanations" of biological reality that reveal more about the writer's creativity than about evolution's. An infamous example was the suggestion by the painter/naturalist Abbott H. Thayer, reported in the book about his "discoveries"—Concealing-Coloration in the Animal Kingdom (1909)—that flamingos were red so as to blend into the sunset: "Conspicuous in most cases, when looked at from above, as man is apt to see them, they are wonderfully fitted for 'vanishment' against the flushed, rich-colored skies of early morning and evening." That unfounded, and inaccurate, speculation generated a spirited and devastating critique from, of all people, another part-time naturalist, the former president Theodore Roosevelt, who pointed out, among other things, that the fact that a raven may be inconspicuous when placed in a coal scuttle does not mean that it evolved its blackness for that reason. Another time, Thayer claimed, in all seriousness, that the patches of white on the head of a skunk have been favored by natural selection because they enable the animals to blend in with the sky when looked at from below, as by a mouse about to be attacked by a predator.

In the current era of neo-Darwinian efflorescence, especially perhaps when it comes to hypothesis-rich evolutionary psychology, an argument can be made that the scientific imagination doesn't need wings so much as weights. But at the same time, and fully recognizing the value of hard-headed realism when it comes to science (and, indeed, to most things), don't forget the value of informed speculation. After all, for all his silliness, Thayer discovered some very important, genuine facts about animal coloration; notably, the camouflage-promoting significance of countershading—whereby many living things are darker on their backs than on their bellies, thereby obscuring their three-dimensionality. His speculations gave rise to decades of productive research on visual patterning in animals, with important military applications as well.

We'd like to propose a revision. To our scientific colleagues: Let's stop running from "just-so story" as an epithet and start embracing its merits. To any nonscientist name-callers: Think again before you sign on to a supposed rebuke that isn't.

When it comes to "doing" science, just-so stories are us. It's not that science ends up being such a story, but it nearly always begins as one, emerging from curiosity, questioning, and uncertainty. It then progresses to reasoned conjecture—to asking, "What if?" and "Could it be?"—and then, if the proffered story seems worth pursuing—and is, in fact, pursuable—to validation, or, as the philosopher Karl Popper and his devotees would have it, to invalidation if not true, and to further refinement if it proves productive. Throughout, the enterprise is steeped in wonder—which includes, not coincidentally, both meanings of the word: as an experience of amazement and appreciation ("the wonder of it all") and as an act of imaginative inquiry ("I wonder if the continents moved" or "I wonder if matter is actually composed of tiny, irreducible particles"). Between wonder, in either sense, and scientific "fact" are just-so stories.

We believe that a just-so story is simply a story, a tentative, speculative answer to a question, and, as such, a clarification of one's thinking, ideally a goad to further thought, and, not incidentally, a necessary preliminary to obtaining the kind of additional information that helps answer a question (which, in the best cases, leads to yet more queries). When that happens—when the narrative is testable and generates fact-based research—then, in a sense, it is no longer a just-so story, but science, pure and … rarely simple.

It bears emphasizing that not all explanations are equally valid, since science arrives at conclusions based on evidence, as opposed to postmodernist poppycock in which every "reality" is imagined to be a culturally constructed "narrative," all equally true. On the other hand, it sometimes takes a while to determine whether pure speculation—as seductive and appealing as it may be—actually connects to the real world. String theory, for example, does not currently have direct empirical support, and thus it may or may not be objectively valid. But string theory has been immensely productive of additional research in basic theoretical physics, even if, according to its critics, it carries possible costs as well: notably, wasteful expenditures of time, money, and human energy. Such downsides, if and when they occur, are probably associated with the "story" in question being a scientific dead end, as were theories about "phlogiston" (a supposed substance liberated when something burns), "ether" (actually, "luminiferous ether," a purported but never identified medium for the propagation of light), and the pre-Copernican, geocentric universe. But the only way to know for certain that a particular path is a dead end is to walk down it a bit and see what happens. And before walking the walk, you've got to talk the talk—which is to say, tell a story.

What is the alternative to proposing a just-so story? One possibility, of course, is that God did it. Another is to emulate Topsy, in Uncle Tom's Cabin, who declared that she "just growed," and conclude that the wings of birds and the echolocation of bats and the eyesight of eagles "just growed," for no particular reason at all. In either case, one would be stuck with supposed "explanations" that didn't explain anything: "just-growed stories."

We prefer Kipling's variety, especially when strongly tinged with a whiff of what evolutionary biologists call "adaptive significance," that is, speculation based on how the trait in question might have evolved because of differential success in projecting its underlying genes into the future. If testable, then so much the better: Just-so becomes just-right.

Hypotheses based on evolution often include precise predictions about a given trait: when it is likely to occur, the degree to which it will show itself, the kind of individuals likely to manifest it, etc. For example, current evolutionary studies of animal (and human) altruism hypothesize that close relatives will interact more benevolently than unrelated individuals, that competitive aggression will be more frequent under resource limitation, that traits contributing to reproductive success will be deemed especially attractive by prospective mates, and so forth. Accordingly, just-so stories don't merely lead, on occasion, to reputable science; they may well be a prerequisite. Scientists don't simply test a random array of hypotheses; rather, they evaluate outcomes only after certain possibilities—e.g., closer relatives will be more altruistic than nonrelatives—are laid out as stories that may or may not be true. We suggest, moreover, that just-so storytelling is a good way to joust, mentally, with the world in general, suitable for everyone, and not just scientists.

Once upon a time, O my Best Beloved, when we two authors were young and the world was so very new and all, and our children even younger, we used to take them on long car trips, during which, when we were finished with Raffi songs and Broadway musicals, we would play the Cream of Mushroom Soup game. It went like this. Picture a bowl of Cream of Mushroom Soup (a staple comfort food in our family). It is composed of little glops of what are supposedly mushrooms, in a matrix of goo, vaguely resembling cream sauce. Now, discuss it from a _____ (fill in the blank) perspective, say, Marxist: How does Cream of Mushroom Soup contribute to the triumph or enslavement of the proletariat? Is it a bourgeois exploitation of the working class, or perhaps an inexpensive means to a worker's paradise? A Chicago School of Economics perspective: Cream of Mushroom Soup flourishes in a free-market economy; does it taste best there, too?

Next, describe Cream of Mushroom Soup as seen by a Platonist: Wherein lies its essential form—the glops or the goo? How would a postmodern deconstruction of Cream of Mushroom Soup compare with a Buddhist approach, which holds that the soup is made of nonsoup elements and is therefore empty of intrinsic form? What about a Jewish outlook? No chicken, ergo no soup! A conservative point of view: Revere and protect this culinary icon, long a mainstay of every patriotic, God-fearing, Reagan-loving American kitchen. Liberal: It is neither local, nor organic, and we do not know its carbon footprint. It should probably not be in the kitchen at all.

You can play the Cream of Mushroom Soup game with anything. How did the leopard get its spots? Why do women conceal their ovulation, or menstruate, or experience orgasms? Where did the alphabet come from? How come the armadillo has a smooth "shell," but the rhino's is wrinkled? How did the camel get its hump? One can approach such questions from many perspectives, as did Kipling. As we drove along, our children learned to ask hard—and sometimes silly—questions and then make up answers from different paradigms, and they learned how those various perspectives worked: Christian, Buddhist, Freudian, Newtonian, Einsteinian, existential, and so on.

We refer the interested reader to Kipling's story "The Crab That Played With the Sea," in which each animal is told to play at being itself: the beaver to play at being a beaver; the cow at being a cow; the turtle at being a turtle. What, then, is the result when people are commanded, encouraged, or—better yet—just plain freed up to play at being human? Our guess is that prominent among the outcomes would be play itself, mental no less than physical.

One can play the Cream of Mushroom Soup game ad infinitum (and, our children might submit, ad nauseam) by deleting the soup and substituting anything—but our favorite paradigm has long been evolution by natural selection, Charles Darwin's very good, very big idea. The reality is that scientists, despite their public image as rigidly humorless and nerdy, are among the most playful of people, constantly trying out various "mind games" on the natural world. By applying the principles of evolutionary biology, biologists have begun to explain how the camel really did get its hump, the leopard its spots, why men and women are different, and so forth. Hint: The camel's hump evolved as a fat-storage organ, especially suitable for a desert-dwelling creature. The leopard's spots convey an adaptive advantage with respect to camouflage, and the differences between men and women largely derive from differing optimum strategies for sperm-making versus egg-making primates, respectively.

Interestingly, many of the most basic aspects of female sexuality are as yet unexplained, so neither we nor any other biologists currently know for certain why women menstruate, why they experience orgasm, why they conceal their ovulation, why they—alone among mammals—have prominent breasts even when not lactating, or why they undergo menopause. But we have enough information to speculate, and we are confident, moreover, that answers will eventually be forthcoming, especially if human curiosity married to creative storytelling is applied to such mysteries, unconstrained by worry that to guess, propose, and wonder is somehow to be lacking in intellectual rigor.

And so, we'd like to help rescue the baby—the thoughtful, imaginative search for explanations—from its supposed contamination by the dirty bathwater of "unscientific" yarn-spinning. We prefer hard-nosed science to "mere guessing," but we hope that even our most serious-minded colleagues will take the latter, any time, over a self-imposed mandate to keep rigidly silent until every "guess," "story," or "hypothesis" can be fully evaluated and subjected to statistical testing.

In one of his finest stories, Kipling expounds upon how the "elephant's child," overflowing with "'satiable curiosity," stuck his short, stubby nose into the "great grey-green, greasy Limpopo River," only to have it bitten by a crocodile, whereupon, following a titanic tug-of-war, it was stretched into a trunk. The good news, for those similarly endowed with scientific curiosity, is that compared with the tribulations of Kipling's petite pachyderm, any such excursions will probably be less painful and more fulfilling, stretching consciousness rather than proboscis.

A brief poem accompanying the story includes the following paean to curiosity:

I keep six honest serving-men:

(They taught me all I knew)

Their names are What and Where and When

And How and Why and Who.

Those "honest serving-men" do double duty. They not only constitute the lure of the Limpopo, they also guide everyone's inner elephant's child on his or her quest to unravel the natural world's enigmas. What and Why and When and How and Where and Who are precisely the kind of honest advisers, the legitimate questions that prod people to propose just-so stories and then to struggle with possible answers—which is to say, to poke around in the Limpopo River and "do" science.

Just so you know.

David P. Barash is a professor of psychology at the University of Washington, and Judith Eve Lipton is a psychiatrist. Their most recent book together is How Women Got Their Curves and Other Just-So Stories: Evolutionary Enigmas (Columbia University Press, 2009).