The snake’s scales, the feathers of the bird, the striations in ancient rocks – though we recognize a commonalty of pattern among these forms, we take pleasure in the distinctions that set them off. No matter how often we are told that feathers are an evolutionary outgrowth of reptilian scales, the tactile sensation of fondling snakeskin or of being caressed by a feather has an inimitable feel. The general fact may illumine but it is the specific that enchants. The world’s surfaces beguile us and give pleasure because each seems individual and unrepeatable, though we know quite well that it isn’t so. My hands will never get tired of the roughness of bark or the sleekness of silk nor will my ears grow indifferent to the rawp of crows or the cadenzas of the mockingbird; and the same is true of the other senses. For me – and for most of us, I suspect – what the Anglo-Irish poet Louis MacNeice called “the drunkenness of things being various” forms an inexhaustible study of delight.

This isn’t how the taxonomist, the logician, the morphologist, or indeed the scientist, sees the world; on the contrary, their tasks are to discern an underlying configuration in the swarm of sensory impressions, to disentangle definitions, to inch toward clarity, however precarious. And I have to concede that the exquisite pleasure of perception of the variousness of things isn’t only enhanced by their labors but in fact is impossible without them. It’s only because I know that certain predictable structures underlie all divergence that I’m able to savor the variants.

Even so, I’m a bit chagrined to learn that almost all living forms in the world can be reduced to a single shape, that of the cylinder. Give me a trapezoid or a parallelogram any day rather than a cylinder; however, having learned this utterly fundamental fact, I am unable now to see anything but cylinders wherever I look. My newfound cylindrical vision has been inspired by a brilliant book titled “Axis and Circumference: The Cylindrical Shape of Plants and Animals” by the zoologist Stephen Wainwright (Harvard University Press, 132 pages, out of print but available for under $10 from Amazon.com). I’d never thought of it before, but virtually everything in nature partakes of the cylindrical. Now, when I look in the mirror, I see the cylinder of my torso to which limbs, also cylinders, have been appended, topped by a thatched cylinder of skull. What this means in structural and evolutionary terms, not only to me but to other cylindroids, is set out here in lucid prose accompanied by exceptionally fine illustrations.

Mr. Wainwright cautions that this ubiquitous pattern obtains only in the organic realm. As he notes,

Man-made buildings are large, dry, rectangular, rigid, and static. In comparison, plants and animals are small, damp, cylindrical, flexible and dynamic. The cylindrical shape is rare in nonorganismic, natural objects; some crystals, stalactites, stalagmites, icicles, and lava tubes are cylindrical, but that is the complete list. In other words, nonliving natural structures and man-made structures are rarely cylindrical.

There are of course exceptions. Neither a turtle nor lettuce is cylindrical. But even if an animal or plant defies the norm, it is usually composed of cylindrical parts. Take the spider, ostensibly noncylindrical yet formed entirely of elongated and axial parts. “Spiders are masters of the tensile thread,” Mr. Wainwright writes. On the spider’s web, which he views as a system in exquisite tension, he waxes eloquent:

Among the most elegant of tensile cords are the silken threads spun by spiders and caterpillars and some of their relatives. Tensile stiffness of the thread supports a spider as she lets herself down from a high perch. The tension a spider puts into a dragline on the ground or into a web enables the spider to detect vibrations made by the animals that stumble into these structures, because vibrations are simply minute and frequent changes in the tension of the thread.

When I look at a spiderweb I take pleasure in its geometry or the way in which light glints on the strands or how the wind makes it swell out like a sail; by contrast, Mr. Wainwright perceives it as a matrix of countervailing forces. And his is the subtler view, for it doesn’t rob the web of its inadvertent beauty but gives it depth. The Roman poet Virgil wrote, “Happy is he who recognizes the causes of things,” and here is a good instance of such felicity.

One of the pleasures of this book is the beauty of its prose. Mr. Wainwright is a terse stylist, but he is also, as befits a man with a love of form and function, a connoisseur of the shapes of sentences. Of the worm, that annelidous cylinder, he remarks, “A worm is essentially a sock full of meat.” This has the wit of an aphorism penned by a hungry robin; even better, it impels us to rethink the worm, no longer just a pink wriggler on rainy sidewalks but a creature whose form has been dictated by function. Or consider the following sentences; they are a perfect illustration of the dictum of the ancient rhetorician Quintillian, “rem tene; verba sequentur” (“hold fast to the thing and the words will follow”):

In most animals, the skeleton is easily seen as a set of its own structural elements, such as bones and shells, separate from other systems. In the muscular hydrostats of molluscs, the turgid pith of wilting plants, and the rigid tissues of woody plants, no such clear separation occurs; it is awkward to speak of the skeleton of a squid, a buttercup, or an oak. Nevertheless, every organism has a mechanical support system.

Axis, our personal longitude, and circumference, the boundaries of the shape that envelopes us, determine us as physical beings, just as they define all other organic life forms. Far from being schematic, this rather drastic simplification of the variety of the world has a liberating effect. The Stoic philosophers of antiquity thought of the world as “a single animal.” By contemplating cylindricality, which links the branching tubes of such elemental creatures as the sponges to the delicate articulations of the human nervous system, we begin to discern the symmetry of that ancient insight. If the world and all the fabulous forms that inhabit it constitute a theme and variations, the dominant melody isn’t drunken, as the poet thought, but extravagantly cylindrical.

eormsby@nysun.com