The Mating Mind: How Sexual Choice Shaped the Evolution of Human Nature

Darwinian evolution is seen as a cold, ruthless struggle for survival that shaped what we eventually became.  But, the critic responds, whence kindness, humor, language, playfulness, art and creativity?  Scientists have tried to explain altruism towards relatives as kin selection and other forms of morality as based on reciprocity, but we all often help people who are not related to us when there’s nothing to be gained.  Geoffrey Miller invokes sexual selection to fill the holes in human nature left unexplained by natural selection.

Reproduction Is as Important as Survival

In The Origin of Species Darwin devoted three pages to sexual selection.  In his second most famous book The Descent of Man, and Selection in Relation to Sex published twelve years later he devoted over 550 out of 900 pages to the idea.  What the scientist understood, and what those who followed him over the next century forgot, was that there were two main forces at work in evolution.  An organism needs to survive and reproduce.  A scrooge that stored up resources and survived just fine but had no interest in socializing with others or finding a mate might as well have died in infancy.  The herd could be culled through natural selection, the inability to survive in the environment, or through sexual selection, the inability to find a mate.  As long as our species is not strictly monogamous, and the vast majority of the time it hasn’t been, choice in romantic matters has helped shape evolution.

Before coming up with the theory, Darwin was confused by how wasteful nature tended to be.  He once told his son Francis that “The sight of a feather in a peacock’s tail, whenever I gaze at it, makes me sick!”  Why should such a thing evolve?  The peacock’s tail is by no means unique.  Across the animal kingdom, males seem to display ornaments that contribute nothing to or even take away from survival.  Some, like the male peacock’s tale, are connected to the body while others are an extended phenotype, something an animal creates.  During mating season, male bowerbirds of Australia and New Guinea spend almost every waking hour building elaborate nests.

Males of most species (of bowerbirds) decorate their bowers with mosses, ferns, orchids, snail shells, berries and bark.  They fly around searching for the most brilliantly colored natural objects, bring them back to their bowers, and arrange them in careful clusters of uniform color.  When the orchids and berries lose their color, the males replace them with fresh material.  Males often try to steal ornaments, especially blue feathers, from the bowers of other males.  They also try to destroy the bowers of rivals.  The strength to defend their delicate work is a precondition of their artistry.  Females appear to favor bowers that are sturdy, symmetrical, and well-ornamented with color.

The genetic ability to grow elaborate physical characteristics or drive to create art are usually found in the sex that competes for mates, i.e., males.  Miller hypothesizes that the human brain itself evolved to impress potential partners.  Not only did it help to deal with practical problems of survival, but a good sense of humor and the ability to make interesting conversation were themselves fitness indicators.  The brain, like the peacock’s tale, couldn’t grow and function properly in a diseased organism.  Thus, a healthy and complicated organ shows that an animal is relatively free of harmful mutations.

So why aren’t males significantly more intelligent than females?  Usually when a trait is sexually selected, in this case intelligence, nature ends up with a huge gender gap.  Part of the answer is that women needed to be able to detect mental fitness in males.  A woman would need to be intelligent enough to know when a male was using big words correctly or making logically consistent arguments.  Miller writes:

According to the widely used WAIS-R intelligence test, for example, English-speaking adult with an IQ of 80 typically know the words “fabric,” “enormous,” and “conceal,” but not the words “sentence,” “consume,” or “commerce.”  IQ 90 speakers typically know “sentence,” “consume,” and “commerce,” but not “designate,” “ponder,” or “reluctant.”  If you are flirting with someone, and they say they would like to “consume” your body in a passionate embrace, but they do not understand when you say you are “reluctant,” you can probably infer they have an IQ between 80 and 90.  We make these sorts of inferences quite automatically and unconsciously, of course.

Where we do see large gender differences is in ambition.  While women have evolved to appreciate art, in all cultures it’s men who mostly create it.

Another check that has kept men from becoming too much smarter than women has been monogamy.  The more polygamy there is in a species, the greater the gender dimorphism (sex differences).  In the polygamous gorillas for example, males are twice as heavy as females.  Humans are moderately dimorphic.  While men are less picky than women about their flings, when it comes to long term commitment the sexes are equally choosy.    Since males were to a certain extent selecting females too, the latter’s mind also evolved to be a fitness indicator.

Taking sexual selection into account explains all other kinds of seemingly inexplicable phenomena.  The average English speaker knows 60,000 words, but only 4,000 account for 98% of all conversation.  Basic English was created in the 1920s with only 850 words and is sufficient to express everything we can in natural English (albeit less efficiently).  So why do we know so many words?  So that friends and mates may be impressed when we use “azure” instead of blue.  As an African-American subject told a linguist,

Yo’ rap is your thing . . . like your personality.  Like you kin style on some dude by rappin’ better ‘n he do.   Show ‘im up.  Outdo him conversation-wise.  Or you can rap to a young lady, you tryin’ to impress her, catch her action-you know-get wid her sex-wise.

Language may have evolved to its complexity as a fitness indicator.  Prepubescent boys communicate just fine in grunts for all practical purposes.  Once language evolved, those who were more intelligent would’ve had more interesting things to say and introspection would’ve been selected for.

Ideals and Morality

Miller believes that, like art, the things we develop called morality, political philosophy, ideals and religion evolved through sexual selection.  As he points out, 99.9% of animal communication has nothing to do with truth content.  Among the few counterexamples are some chimp calls, bee dances, and (sometimes) human language.  Most communication exists solely to indicate fitness, like a frog’s mating call or the bowerbird’s nest.

Communicating truth can sometimes give us an advantage in terms of survival, but not in the competition for sexual success.  Imagine two cavemen getting into an argument about the purpose of the universe.

The hominid names Carl proposes: “We are mortal, fallible primates who survive on this fickly savanna only because we cluster in jealousy-ridden groups.  Everywhere we have ever traveled is just a tiny, random corner of a vast continent on an unimaginably huge sphere spinning in a vacuum.  The sphere has traveled billions and billions of times around a flaming ball of gas, which will eventually blow up to incinerate our empty, fossilized skulls.  I have discovered several compelling lines of evidence in support of these hypotheses . . .”

The hominid named Candide interrupts: “No, I believe we are immortal spirits gifted with these beautiful bodies because the great god Wug chose us as his favorite creatures.  Wug blessed us with this fertile paradise . . . Above the azure dome of the sky the smiling sun warms our hearts.  After we grow old . . . Wug will lift us from our bodies to join our friends to eat roasted gazelle and dance eternally.  I know these things because Wug picked me to receive this special wisdom in a dream last night.”

Which ideology do you suppose would prove more sexually attractive?

Muhammad and Brigham Young left behind more descendants than any scientist ever did.  We are a species that evolved to care about status, not truth.

People generally do things perceived as moral so people will have a positive opinion of them.  Not only is kindness attractive in a mate, but we can see how the evolution of ethics has worked by invoking the handicap principle.  In addition to the peacock’s tail being visually appealing, it makes surviving more difficult.  The male bird is saying “Not only does this nice tail show that I am mutation free, but I’ve been able to avoid predators will carrying this ridiculous thing around.”

The Israeli biologists Amotz and Avishag Zahavi in their book The Handicap Principle talk about a group of birds known as the Arabian babblers.  This species engages in competition to see who can be the most altruistic.  Dominant babblers won’t allow subordinate ones to take the risk of making the alarm call when a predator approaches.  The birds will try to shove food down the throats of non-relatives.  The Zahavis argue that the birds show their fitness by handicapping themselves.  Whether the disadvantage that the animal is trying to prove its fitness with is a physical appendage or an act, the principle is the same.

Excessive altruism in humans can work like this.  “I am so fit that I can afford to give millions to charity (or not worry about affirmative action helping those poor blacks, or whatever) and do it gladly.”   Ted Turner revealed that when he donated a billion dollars to the UN his wife Jane Fonda broke down and cried.  Aid organizations know that they can set off an arms race for donations by attracting a few rich donors.  Next time you see Angelina Jolie with her multiracial brood, you’ll understand why.

Those of us who rally against PC understand the frivolity of the beliefs of most people.  As Miller puts, it:

When individuals espouse ideological positions, we typically interpret their beliefs as signs of good or bad moral character. . . . Political correctness is one outcome of such attributions.  For example, if a scientist says, “I have evidence that human intelligence is genetically heritable,” that is usually misinterpreted as proclaiming, “I am a disagreeable psychopath unworthy of love.”  The arbiters of ideological correctness can create the impression that belief A must indicate personality trait X.  If X is considered sexually and socially repulsive, then belief A becomes taboo.  In this way our sexually selected instincts for moralistic self-advertisement become subverted into ideological dogmas.

He then adds that “I think that human rationality consists largely of separating intellectual arguments from personality attributions about moral character.”  Miller must understand that he’s a Darwinian rarity.

Sexual selection doesn’t care if what it favors is a good long term strategy.  The Irish elk evolved antlers so big that other functions of life, such as maybe reproduction, became impossible.  Any human population that adopts a maladaptive morality will move in a similar direction.

Evolutionary Psychology and Human Nature

The Mating Mind presents a much more colorful and interesting picture of evolution than what we’re used.  Our appreciation of music, art and oratory are just as natural and purposeful as our enjoyment of food and sex.  Miller hopes that Darwinism and evolutionary psychology will replace Freudianism, Marxism, and culturalism as the center of the humanities.  Truth will always remain as intellectual fads come and go.  If and when it does triumph in the human science, Geoffrey Miller’s theory of brain evolution may very well be a central part of the explanation of who we are.

Spent: Sex, Evolution, and Consumer Behavior

When I was asked to review this book, I half groaned because I was sure of what to expect and I also knew it was not going to broaden my knowledge in a significant way. From my earlier reading up on other, but tangentially related subject areas (e.g., advertising), I already knew, and it seemed more than obvious to me, that consumer behavior had an evolutionary basis. Therefore, I expected this book would not make me look at the world in an entirely different way, but, rather, would reaffirm, maybe clarify, and hopefully deepen by a micron or two, my existing knowledge on the topic. The book is written for a popular audience, so my expectations were met. Fortunately, however, reading it proved not to be a chore: the style is very readable, the information is well-organized, and there are a number of unexpected surprises along the way to keep the reader engaged.

Coming from a humanities educational background, I was familiar with Jean Baudrillard’s treatment of consumerism through his early works: The System of Objects (Radical Thinkers) (1968), The Consumer Society: Myths and Structures (1970), and For a Critique of the Political Economy of the Sign (1972). Baudrillard believed that there were four ways an object acquired value: through its functional value (similar to the Marxian use-value); through its exchange, or economic value; through its symbolic value (the object’s relationship to a subject, or individual, such as an engagement ring to a young lady or a medal to an Olympic athlete); and, finally, through its sign value (the object’s value within a system of objects, whereby a Montblanc fountain-pen may signify higher socioeconomic status than a Bic ball-pen, or a Fair Trade organic chicken may signify certain social values in relation to a chicken that has been intensively farmed). Baudrillard focused most of his energy on the latter forms of value. Writing at the juncture between evolutionary psychology and marketing, Geoffrey Miller (an evolutionary psychologist) does the same here, except from a purely biological perspective.

The are three core ideas in Spent: firstly, conspicuous consumption is essentially a narcissistic process being used by humans to signal their biological fitness to others while also pleasuring themselves; secondly, this processes is unreliable, as humans cheat by broadcasting fraudulent signals in an effort to flatter themselves and achieve higher social status; and thirdly, this process is also inefficient, as the need for continuous economic growth has led capitalists since the 1950s to manufacture products with built-in obsolescence, thus fueling a wasteful process of continuous substandard production and continuous consumption and rubbish generation. In other words, we live in a world where insatiable and amoral capitalists constantly make flimsy products with ever-changing designs and ever-higher specifications so that they break quickly and/or cause embarrassment after a year, and humans, motivated by primordial mating and hedonistic urges that have evolved biological bases, are thus compelled to frequently replace their consumer goods with newer and better models — usually the most expensive ones they can afford — so that they can delude themselves and others into thinking that they are higher-quality humans than they really are.

Miller tells us that levels of fitness are advertised by humans along six independent dimensions, comprised of general intelligence, and the five dimensions that define the human personality: openness to experience, conscientiousness, agreeableness, stability, and extraversion. Extending or drawing from theories expounded by Thorstein Veblen and Amotz Zahavi (the latter’s are not mainstream), Miller also tells us that, because fraudulent fitness signaling is part and parcel of animal behavior, humans, like other animals, will attempt to prove the authenticity of their signals by making their signaling a costly endeavor that is beyond the means of a faker. Signaling can be rendered costly through its being conspicuously wasteful (getting an MA at Oxford), conspicuously precise (getting an MIT PhD), or a conspicuous badge of reputation (getting a Harvard MBA) that requires effort to achieve, is difficult to maintain, and entails severe punishment if forged. Miller attempts to highlight the degree to which these strategies are wasteful when he points out that, in as much as university credentials are a proxy for general intelligence, both job seekers and prospective employers could much more efficiently determine a job seeker’s general intelligence with a simple, quick, and cheap IQ test.

As expected, we are told here that signaling behavior becomes, according to experimental data, exaggerated when humans are what Miller calls “mating-primed” (on the pull). Also as expected, men and women exhibit different proclivities: males emphasizing aggression and openness to experience by performing impressive and unexpected feats in front of desirable females, and females emphasizing agreeableness through participation in, for example, charitable events. And again as expected, Miller tells us that while dumb, young humans engaging in fitness signaling will tend to emphasize body-enhancing consumption (e.g., breast implants, muscle-building powders, platform shoes), older, more intelligent humans, educated by experience on the futility of such strategies, instead emphasize their general intelligence, conscientiousness, and stability through effective maintenance of their appearance, via regular exercise, sensible diet, careful grooming, and tasteful fashion. Still, this strategy follows biologically-determined patters: as women’s physiognomic indicators of fertility (eye size; sclera whiteness; lip coloration, fullness, and eversion; breast size; etc.) peak in their mid twenties, older women will apply make-up and opt for sartorial strategies that compensate for the progressive fading of these traits, in a subconscious effort to indicate genetic quality and stability, as well as — as mentioned above — conscientiousness.

Less expected were some of the explanations for some human consumer choices: when a human purchases a top-of-the-line, fully featured piece of electronic equipment, be it a stereo or a sewing machine, the features are less important than the opportunity the equipment provides its owner to talk about them, and thus signal his/her intelligence through their detailed, jargon-laden enumeration and description. This makes perfect sense, of course, and reading it provided theoretical confirmation of the correctness of my decision in the 1990s, when, after noticing that I only ever used a fraction of all available features and functions in any piece of electronic equipment, I decided to build a recording studio with the simplest justifiable models by the best possible brands.

Even less expected for me where some of the facts outside the topic of this book. Miller, conscious of the disrepute into which the evolutionary sciences have fallen due to foaming-at-the-mouth Marxist activists — Stephen Jay Gould, Leon Kamin, Steven Rose, and Richard Lewontin — and ultra-orthodox nurture bigots in modern academia, makes sure to precede his discussion by describing himself as a liberal, and by enumerating a horripilating catalogue of liberal credentials (he classes himself as a “feminist,” for example). He also goes on to cite survey data that shows most evolutionary psychologists in contemporary academia are socially liberal, like him. It is a sad state of affairs when a scientist feels obligated to asseverate his political correctness in order to avoid ostracism.

Unusually, however, Miller seems an honest liberal (even if he contradicts himself, as in pp. 297-8), and is critical in the first chapters as well as in the later chapters of the Marxist death-grip on academic freedom of inquiry and expression and of the cult of diversity and multiculturalism. The latter occurs in the context of a discussion on the various possible alternatives to a society based on conspicuous consumption, which occupies the final four chapters of this book. Miller believes that the multiculturalist ideology is an obstacle to overcoming the consumer society because it prevents the expression of individuality and the formation of communities with alternative norms and forms of social display. This is because humans, when left to freely associate, tend to cluster in communities with shared traits, while multiculturalist legislation is designed to prevent freedom of association. Moreover, and citing Robert Putnam’s research (but also making sure to clarify he does not think diversity is bad), Miller argues that “[t]here is increasing evidence that communities with a chaotic diversity of social norms do not function very well” (p. 297). Since the only loophole in anti-discrimination laws is income, the result is that people are then motivated to escape multiculturalism is through economic stratification, by renting or buying at higher price points, thus causing the formation of

low-income ghettos, working-class tract houses, professional exurbs: a form of assortative living by income, which correlates only moderately with intelligence and conscientiousness.

. . .

[W]hen economic stratification is the only basis for choosing where to live, wealth becomes reified as the central form of status in every community — the lowest common denominator of human virtue, the only trait-display game in town. Since you end up living next to people who might well respect wildly different intellectual, political, social, and moral values, the only way to compete for status is through conspicuous consumption. Grow a greener lawn, buy a bigger car, add a media room . . . (p. 300)

This is a very interesting and valid argument, linking the evils of multiculturalism with the consumer society in a way that I had not come across before.

Miller’s exploration of the various possible ways we could explode the consumer society does get rather silly at times (at one point, Miller considers the idea of tattooing genetic trait levels on people’s faces; and elsewhere he weighs requiring consumers to qualify to purchase certain products, on the basis of how these products reflect their actual genetic endowments). However, when he eventually reaches a serious recommendation, it is one I can agree with: promoting product longevity. In other words, shifting production away from the contemporary profit-oriented paradigm of cheap, rapidly-obsolescing, throwaway products and towards the manufacture of high quality, long-lasting ones, that can be easily serviced and repaired. This suggests a return to the manufacturing standards we last saw during the Victorian era, which never fails to put a smile on my face. Miller believes that this can be achieved using the tax system, and he proposes abolishing the income tax and instituting a progressive consumption tax designed to make cheap, throwaway products more expensive than sturdy ones.

Frankly, I detest the idea of any kind of tax, since I see it today as a forced asset confiscation practiced by governments who are intent in destroying me and anyone like me; but if there has to be tax, if that is the only way to clear the world out of the perpetual inundation of tacky rubbish, and if that is the only way to obliterate the miserable businesses that pump it out day after day by the centillions, then let it mercilessly punish low quality — let it sadistically flog manufacturers of low-quality products with the scourging whip of fiscal law until they squeal with pain, rip their hair out, and rend their garments as they see their profits plummet at the speed of light and completely and forever disappear into the black hole of categorical bankruptcy.

If you are looking for a deadly serious, arid text of hard-core science, Spent is not for you: the same information can be presented in a more detailed, programmatic, and reliable manner than it is here; this book is written to entertain as much as it is to educate a popular audience. If you are looking for a readable overview, a refresher, or an update on how evolved biology interacts with marketing and consumption, and would appreciate a few key insights as a prelude to further study, Spent is an easy basic text. It should be noted, however, that his area of research is still in relative infancy, and there is here a certain amount of speculation laced with proper science. Therefore, if you are interested in this topic, and are an activist or businessman interested in developing more effective ways to market your message or products, you may want to adopt an interdisciplinary approach and read this alongside Jacques Ellul’s Propaganda, Jean Baudrillard’s early works on consumerism, and some of the texts in Miller’s own bibliography, which include — surprise, surprise! — The Bell Curve, by Richard Herrnstein and Charles Murray, and The Global Bell Curve, by Richard Lynn, among others.