Archive for December 20, 2015

The Eight Pillars of Beauty

In the early 1990’s in Vienna the biological anthropologist Karl Grammer and his colleagues noticed that symmetrical scorpion flies attract more mates than asymmetrical ones.  On the hunch that what’s true for the courting of scorpions might also be true for the courting of humans, they examined perceptions of symmetry in people and learned that symmetry was one of the features we associate with beauty.  Not just “we” in Vienna, but people all over the world.  In one of their studies, people from South Africa and Austria judged the same Japanese women to be attractive.


Though until the 1990’s there had been little research on the science of beauty—the topic was considered politically incorrect during the 1960’s and 1970’s—Grammer spent the next 15 years studying what we think of as beautiful and how beauty drives much of our behavior, from who we court to how we dress to what we buy to adorn ourselves.  After reading in a recent issue of Nature an interview with Grammer, in which he identifies “eight pillars of beauty,” I began to wonder how he and others had arrived at this list and how robust the research has been.

The best answer I’ve found is their review of their work published in 2003, titled “Darwinian Aesthetics: sexual selection and the biology of beauty.”  Over 140 references, mostly from the previous 15 years, convinced me they had plenty of good company in a wide range of disciplines who had published in sound scientific journals.  And they summarize the evidence for and against their assertions, suggesting they have done their homework on both sides of the arguments.  Here are a few notes on how they elaborate on these eight pillars of beauty.

Symmetry.  Nature has selected against asymmetries since the beginning of reproduction.  Asymmetric gametes (the organisms after the sperm and egg meet and start multiplying) don’t survive.  All plants and animals that survive show features of symmetry, and among primates obvious asymmetries usually lead to harsh exclusion by all but the most compassionate groups.  Symmetry also favors efficient movements, which for most species is essential to survival.

Youthfulness.  It is no accident that our icons of beauty tend to be in their reproductive years, between the late teens to the late forties.  Babies and children can be “cute,” but they don’t evoke the power of youthful beauty.  The elderly too can be attractive, but often in ways that retain the features of their youth.  The pitch from plastic surgeons and cosmetologists is that they can help you prolong the appearance of your youth.

Averageness.  We have learned to be wary of the extremes of human appearance as indicators of risky genes.  And the circuits in our brains for recognizing faces and bodies operate on prototypes.  Faces and bodies that don’t fit the general rules of our prototypes trigger alarm or indifference.  Try turning a picture of a face upside down and see how long it takes you to recognize it.  So we are programmed to be attracted to people who fit our concept of average humanness.

Sexual dimorphism.  Clarity of gender and readiness for reproduction have driven our sense of what makes a woman or a man attractive.  The broad male chin signals ample testosterone, but too broad a chin may signal too much aggression, a disadvantage in caring for the offspring.  The high cheekbones and smaller chins and lower facial features that signal ample estrogen differentiate the fertile woman from the undeveloped girl or boy.  The body shape of the fertile woman also signals adequate storage for estrogen in breasts and hips.  The recent effort to consider gender along a continuum instead of a binary phenomenon poses a challenge to this feature of beauty.

Body scents.  Did you know that women show a distinct preference for the body scents of “symmetric men” during the ovulatory phase of the menstrual cycle?  If you know some symmetric men who don’t smell so hot, imagine what “asymmetric” men smell like!  Sorry, we haven’t yet evolved beyond such animalistic things as pheromones.  Maybe some day soon.

Movement.  We can quickly identify a person’s gender by watching gait.  How a person moves also tells us something about age, health, and ability to compete against others.  No wonder dance plays a ritual role in most cultures.  No wonder we’re fascinated by the movements of our young and often attractive athletes.

Skin complexion and hair texture.  One of the better outward indicators of the state of a person’s immune system is the state of his skin and hair.  Blemishes and hair loss often reflect difficulty with parasites.  When choosing a mate, you’re choosing your mate’s parasites too.  Make sure he or she has good control over those buggers.


Why eight pillars of beauty, and not seven or ten?  That number seems to be a moving target that depends on the state of the research. When Grammer and colleagues published their review in 2003, they devoted some ink to the role of the voice in attractiveness, but there has been little research about the effect of voices on perceptions of beauty, so this gap in research apparently dropped it from the list.  More recent research about skin complexion and hair texture as indicators of immune function has added those two “pillars” to the list.  Science is always remodeling its house.

In the next blog, we’ll wonder aloud what this list tells us about how our highly evolved sense of beauty draws us so powerfully to the less human marvels of rainbows and songbirds and Beethoven’s seventh symphony and the mesmerizing shape of an egg.

The Science of Beauty

‘Beauty is truth, truth beauty,–that is all

Ye know on earth, and all ye need to know.’

Keats, Ode on a Grecian Urn



When I first read these lines in my high school English class on the romantic poets, I wondered what might be wrong with me that I could not find such ecstasy over the beauty in that “still unravish’d bride of quietness” on the Grecian urn.  Now I wonder what might have been wrong with young Keats, but these lines have earned him much ink and hard thought by many people smarter than me.  Is beauty really the only truth we need to know?  What I know now about beauty in people after another fifty years of wondering is that a heavy dose can make me shiver or weep.  But how and why that happens is still a mystery, artful magic that demands a handkerchief.

At the California wedding I attended in October seven bridesmaids in matching blue dresses, each with lush hair and radiant complexions, strode at a graceful pace down the aisle toward the altar, each in step with the groomsman on her elbow and with the beat of the processional tune, each adorned with a fragrant gardenia, taking her place opposite her male counterpart to form the wings that would focus our attention on the bride and groom in the center.   Such a concentration of gorgeousness demanded my handkerchief.   And at the Arkansas wedding I attended a month later the same ritual played itself out, to equally wet effect.  Weddings pull out all the stops for this kind of beauty.

But what truths do we know about beauty and how it works on us?  The October 8, 2015, issue of the weekly journal Nature devotes its Outlook Supplement to nine articles on the science of beauty, providing some truths that Keats and the rest of us can only dimly sense.  Have you ever wondered why we think of Neanderthals as ugly?  The Nature interview with Karl Grammer, an Austrian anthropologist, describes the role that beauty has played in natural selection and evolution.  Beauty favors attraction, and attraction favors contact, the kind that leads to procreation.  That is, beautiful people make more babies.  The not-so-beautiful people lose in the competition, so they’re weeded out of the gene pool.  This is true not only for Neanderthals and fashion models, but for flies, butterflies, and orangutangs.  All species engage in the ultimate beauty contest, and our sense of beauty may be rooted in those features that attract us to each other for procreation.

But for humans, isn’t “beauty in the eye of the beholder,” a fickle thing subject to fashion or decree? No, say several articles in this series.  Our sense of beauty is shared across all cultures and is wired into our human brains.  Here are the eight “pillars of beauty” that we instinctively find attractive in Biloxi, Borneo, or Beijing:

  • Symmetry
  • Youthfulness
  • Averageness
  • Sexual dimorphism (sex-hormone markers)
  • Healthy body odors
  • Graceful Motion
  • Skin complexion
  • Hair texture


Both wedding parties paraded these pillars of beauty (such a show at a funeral might seem obscene).    The evolutionists tell us that these universal pillars of beauty advertise robust health and fertility.  People (and animals) who find these traits attractive tend to have greater success breeding healthy offspring. Natural selection has chosen you and your ancestral line because of your impeccable instincts for who might breed well.

The article on “The Aesthetic Brain” describes the neuroanatomy and brain circuits that underlie our abilities to sense beauty as an indicator of health and fertility.  We attract each other through complex circuits for experiencing arousal, seeking and feeling the rewards of sex, and learning to establish the relationships that not only make the babies but raise them.  The capacity to be attractive and attracted to others overlaps with the capacity to trust and be trusted.  Beauty helps us get started, but it doesn’t do the dirty work of raising the kids.

The science of beauty has not been lost on the merchants.  Long ago they learned how to prey on our vanity and our fascination with beauty.  Now the cosmetics industry flourishes, and the newest merchant, the cosmetic surgeon, has more options than ever for catering to the wants of those who can afford to purchase symmetric faces, youthful complexions, and lush crops of hair in the right places.  You can now boost your beauty index through hormones, cosmetic surgery, joint replacement, hairstyling, exercise, and daily cosmetics.  The beauty culture has taken on a value of its own, beyond chasing fertility, because beauty is so intimately linked with pleasures of many kinds that have little to do with procreation, such as art, music, science, and entertainment.

The interview with the physicist David Deutsch raises the question of why flowers, which evolved to attract insects, are so attractive to people.  Deutsch asserts that the essentials of beauty cut across species, “and these aesthetic truths are as objective as the laws of physics or maths.”  This assertion leaves us with some tantalizing questions.  If our aesthetic sense is rooted in features that attract us to fertile members of our own species, what is it about sunsets and campfires and gardenias that fascinate us all?  How can Beethoven’s Seventh Symphony be so universally beautiful without featuring any of the “eight pillars of beauty”?  Is beauty just another word for attraction, the kind that can happen at any level, from the bride and groom down to quarks and leptons?

Maybe that’s what Keats meant.  The only truth we need to know to survive is the art of attraction.