How easy it would be, a young Susan Sontag considered, to slide into academic life. Make good grades, linger in graduate school, write “a couple of papers on obscure subjects that nobody cares about, and, at the age of sixty, be ugly and respected and a full professor.” Nearly 70 years after this journal entry, the word “ugly,” planted so squarely in the sentence’s final phrase, still stings.
Academe styles itself as the aristocracy of the mind; it is generally disdainful of the body and of the luxury goods commercial society finds beautiful. In short, professors distrust beauty. The preening self-abasement with which they do so, Stanley Fish wrote in the 1990s, is why academics take pride in driving Volvos.
In truth, beauty’s conflicted status among academics probably derives less from the elevation of mind over body and more from the long exclusion of women from the professoriate. For most of the 20th century to be a professor was to be male, and therefore theoretically unsexed, and thus seemingly exempt from the female gendered standards of the fashion industry and mass entertainment. Female academics face a double bind: Look attractive and you seem unserious; look homely and you seem dour. Male academics, for their part, loll in ink-stained corduroys and rumpled shirts. The fashion-conscious few adopt intellectual aesthetics, for instance, riffs on Foucault with black turtlenecks, sleek, shaved heads, and big plastic glasses thrown in for good measure.
That academics encounter beauty in their private lives as a mystifying or corrupted alien force was a cliché by the time Fish cast his eye on the faculty parking lot. Yet the inconsistent treatment beauty has received in scholarly research demands explanation. In the humanities, beauty is ignored or seen as a vague embarrassment, and in the social sciences the topic is treated only superficially. If beauty remains a serious subject of study anywhere, it is in the sciences, certain corners of which have enlisted beauty as an organizing ideal.
In the 1980s and 1990s, Elaine Scarry charged in On Beauty and Being Just (Princeton University Press, 1999), beauty was barred from humanities seminar rooms, art studios, and architecture schools. To write about the sensual pleasure of poems or paintings reeked of an aristocratic belletrism. Complaints that beauty was a luxurious distraction from the sufferings of the world, or that standards of beauty harmed women, settled on the humanities like a layer of coal dust.
In law, economics, gender studies, psychology, sociology, and other social-scientific fields, “beauty studies” connotes merely the study of physical appearance. Scholars have investigated the relationship between attractiveness and social dominance; how physical allure can be leveraged for economic opportunity and esteem; and how homeliness can invite discrimination (a phenomenon known as “lookism”). One economist has reckoned that beautiful people in the United States earn $230,000 more over the course of their lifetimes than unbeautiful ones. These subjects are worthy of study, but those of us longing for deeper answers may be dismayed by the skin-deep analysis.
The inconsistent treatment beauty has received in scholarly research demands explanation.
In the natural sciences alone does a metaphysical, spiritualized conception of beauty retain credibility as an explicit category of analysis. The language of aesthetics has survived persistently, if controversially, in such fields as physics, mathematics, chemistry, and astronomy, where appeals to the elegance of a proof, the beauty of the golden ratio, the intricacy of a chemical structure, or the ineffability of the cosmos are familiar. Thus, book titles like A Beautiful Question: Finding Nature’s Deep Design, The Accelerating Universe: Infinite Expansion, the Cosmological Constant, and the Beauty of the Cosmos, and The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory raise few eyebrows with their invocations of aesthetic bliss.
These abstract, formal sciences, dedicated largely to the elucidation of pattern and structure, celebrate a beauty that is cool and impersonal: fractals and spheres; the crystalline arrangement of atoms; the possibility of symmetry in the fundamental forms of matter. The objects of beauty in physics and mathematics are purified models that transcend particular phenomena. In these disciplines, beauty is a conceptual, not a sexual, ideal.
This bloodless, geometric notion of beauty faces a new challenge from within the sciences. Recent evolutionary-biological inquiry into beauty is, like physics, awed by the power of the aesthetic. But new scholarship brings a messier, and sexier, form of beauty into view. A crop of recent books sees beauty as a sensual, bodily experience, rooted in animal perceptions and shaped by sexual desire. To make sense of the overwhelming presence of beauty in the natural world, we may need to credit sexual selection as a driving force in the history of evolution. And this science encourages us to consider beauty not as a rarified lodestar but as — simply, thrillingly — the ground of life.
In The Evolution of Beauty (Doubleday, 2017), Richard O. Prum, a professor of ornithology at Yale, revives a long-neglected Darwinian idea: the claim that ornamental traits in animals — the curl of antlers, the gold splash of plumage, the trill of birdsong — are produced by aesthetic preferences. Darwin was troubled by the ubiquity of “useless beauty” in the animal world. Everywhere he looked he saw traits that were attractive but maladaptive. “The sight of a feather in a peacock’s tail,” he famously wrote, “whenever I gaze at it, makes me sick!” Prum insists, following Darwin, that such display traits evolve because they are attractive — not because they signal an animal’s fitness.
Prum’s defense of nonadaptive mate choice is the latest shot fired in a long war within evolutionary biology about how far natural selection, rather than other mechanisms such as sexual selection, can explain the evolution of physical traits. In a seminal 1979 essay, “The Spandrels of San Marco,” Stephen Jay Gould and Richard C. Lewontin cautioned scientists against presuming that all biological traits are adaptations. Many traits are byproducts of adaptations, or genetically linked to adaptive traits — not selected for in their own right.
Nearly four decades later, adaptationism still rules evolutionary biology. Evolutionary scientists, when examining a given organ or structure, typically begin, the philosopher of science Elisabeth Lloyd observes, by asking “What is the function of this trait?” instead of the more modest “Does this trait have a function?” Traits are assumed adaptive until proven otherwise.
The world brims with adaptations: the dangling tongue of an anteater, the bulging hump of a camel. But other evolutionary factors also affect biological traits. A maladaptive characteristic can persist because of embryological constraints, or because prior adaptations have blocked off more optimal evolutionary pathways. Other biological features evolve as byproducts of traits strongly selected for in the opposite sex of the species. Male nipples, for example, are a “useless” byproduct trait, present because of strong selection on nipples in females. Prum, like Gould and Lewontin — and, for that matter, like Darwin — sees evolutionary change as having multiple causes.
Yet because adaptive explanation remains the field’s gold standard, many evolutionary biologists have recast sexual selection as natural selection by other means. The most influential version of this recasting is the “handicap principle” developed by the Israeli evolutionary biologist Amotz Zahavi. According to Zahavi, sexual ornaments (such as the male peacock’s tail) signal adaptive fitness by imposing a survival cost — a handicap — on the signaler. Males who survive despite their costly ornaments are likely to have “better” genes. A mating preference for a costly display trait, to this view, is adaptive: The sexual ornament provides honest information about mate quality.
While ceding that some cases of sexual display serve a signaling function, Prum is not convinced that sexual desire in animals can be reduced to an inchoate longing for genetically superior mates. Many studies have failed to find a correlation between good genes and female sexual preferences. Some instances of sexual selection are even maladaptive. The club-winged manakin, a small bird found in the forests of Ecuador, has become clumsier in flight because it has evolved distorted wing bones that allow males to perform violinlike “wing songs” in mating displays. Such extreme forms of beauty persist because the advantages of having “sexy” male offspring outweigh the functional costs. But this aesthetic extremism can harm the fit between organisms and their environment, or doom a species to extinction.
Zahavi’s signaling theory, Prum reasons, also fails to explain complex systems of display traits, like the feathers of the great argus, a species of pheasant. In its mating display, the male argus assumes a blown-out-umbrella posture to show off feathers of staggering visual complexity. Twisted bars, fanning swirls, and golden-brown, eyelike spheres blink from a hemispherical feather-bouquet. If Zahavi’s theory were correct, argues Prum, then each additional ornamental feature in the argus’s display must provide an independent source of information about mate quality in order to recoup its “costs.”
The theory of sexual selection holds that animals can exercise something akin to aesthetic judgment in their mating behavior — judgments that may be profoundly subjective or crudely mechanistic. Some animals are more aesthetic than others. One species of bowerbird crafts intricate structures of twigs and flowers that rise waist high and spread more than one yard wide. Another species will shred writhing beetles, or kill small blue birds, to acquire blue pigment for its bowers. Of all the world’s beauty-loving creatures, Darwin surmised, birds are second only to man. Prum suggests that male manakins, which spend most of their time rehearsing and performing song-and-dance displays of spiraling flights, easily eclipse human beings in aesthetic fervor.
What determines the physical features an animal finds beautiful? The answer Michael J. Ryan offers in A Taste for the Beautiful: The Evolution of Attraction (Princeton University Press, 2018) is sensory exploitation. “Beautiful” traits exploit sensory preferences already built into an animal’s food-detection or predation systems. Female guppies, for example, feed on orange fruit and prefer males with orange coloration. Why? Because male guppies have evolved orange coloration to take advantage of a general attraction to orange that arose first in the realm of food preference, then migrated to mate preference.
Ryan, a professor of zoology at the University of Texas at Austin, argues that across a number of species, the neural systems that help an animal find food, avoid predators, or recognize other members of its species can be repurposed for sexuality. Species that hunt for bright-colored prey are likely to hunt also for bright-colored mates.
Some animals appear to have sexual-aesthetic preferences that go untapped until a novel trait emerges and unleashes the previously latent desire. In one experiment, scientists attached artificial “swords” to the tails of platyfish, a close relative of the swordtail, to see how female platyfish would respond. The females preferred the artificially endowed, swordtail-like males. Each species has different aesthetic proclivities, Ryan finds, but certain patterns of beauty — magnitude, complexity, and novelty — are favored across many species and sensory modes.
The expansion of ‘beauty studies’ to biology signals a shift from the ascetic to the aesthetic.
Sensory exploitation, Ryan hypothesizes, is an adaptive mechanism that improves survival prospects by reducing female search costs. “The sexual marketplace,” he writes, “is a dangerous place ... It is the only place to shop for a mate, but it is also filled with predators shopping for food and parasites looking for a home.” The ability to locate a mate quickly, in other words, might boost your survival chances.
One of Ryan’s favorite animals, the túngara frog of Panama, does indeed inhabit a dangerous sexual marketplace. Males that add too many “chuck” sounds to their mating whines risk being devoured by circling bats. Not all species, however, mate in such exposed territory. And some of the most ornate sexual displays in nature — the cooperative dances of male manakins, the unfurled feathers of the great argus — occur after the female has approached, rendering search costs irrelevant.
The idea that sensory exploitation evolves to reduce search costs is highly plausible for species that mate in short bursts in high-risk areas, but not for species like the manakin or argus. Let us suppose, with Ryan, that sensory exploitation drives sexual selection in a large number of species. A more capacious theory would say that sensory exploitation emerges because animals find the exploitation of latent preferences pleasurable, even if such changes fail to increase fitness. Only if we are willing to entertain nonadaptive explanations might sensory exploitation shed light on, as Ryan claims, sexual beauty throughout much of the animal kingdom. On the evidence he offers, however, the range of species that practices sensory exploitation in mating may be quite narrow.
Things get more complicated as Ryan moves from the sexual-aesthetic preferences of fish and frogs to those of humans. He resurrects the long-unsupported claim that humans and other animals have a “hard-wired preference for symmetry.” He claims that women prefer men with “more masculine features, such as broader shoulders and deeper voices.” In fact, numerous studies show that women favor intermediate or even “feminine” facial features in men over the most “masculine” features (square jaws, wide brows, thick eyebrows, full beard).
Beauty differs from the other ideals with which it is often grouped — truth, goodness, justice — in that its presence in the world is not disputable. To deny the existence of beauty is to reject the evidence of our senses. When we are in the presence of beauty, Plato writes, “the whole soul seethes and throbs” in a stinging composite of anguish and joy.
Beauty, in other words, is a sensuous, bodily experience. By locating aesthetic perception in nonhuman animals, by marking the close relation between aesthetic preferences and sexuality, and by theorizing about the neural mechanisms that govern judgments of beauty, Prum and Ryan restore beauty to the body. This expansion of “beauty studies” to biology signals a shift from the ascetic to the aesthetic — from beauty as purified ideal to beauty as a fact of ordinary perception. Yet this somatization of beauty is no disenchantment. The ubiquity of sexual selection suggests that aesthetics helped determine the development of the organic world.
In the monastic culture of academic study in an age of austerity, the lure of beauty will almost always lose to the (equally seductive) promise of the clarity fueled by self-denial. And yet the academy remains, in other ways, the holding ground for aesthetic sensibility in a period that places scant value on natural or artistic beauty. Scholars in the humanities are fond of saying that the aesthetic yearnings of human beings express, and nourish, our humanity. If aesthetic desires have shaped the course of evolution, as Prum and Ryan would have us think, then a stronger claim seems possible. It may be no exaggeration to say that the longing for beauty, felt over countless generations, has literally made us human — and made, beyond us, a world of endless forms.