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Mean Genes

Mean Genes

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October 14, 2001

BOOK REVIEW: Mean Genes: From Sex to Money to Food, Taming Our Primal Instincts. By Terry Burnham and Jay Phelan. (New York: Perseus Book Group, 2000. 224 pp. $24.00; $13.00, paper.)

October 2001 -- For a vacation in hell, try studying the minds of monkeys in Puerto Rico for a summer. Each morning for two months, I awoke before dawn to take a dinghy out to an isolated tropical island and spend all day hiking with heavy equipment over hills and through dense brush in direct sunlight, three-digit temperatures, and extreme humidity. It took me days to complete each experiment because I didn't know how to work with the violent, skittish free-ranging rhesus macaques. My body was perpetually covered with sweat, mud, monkey excrement, mosquito bites, sunburn, and an unidentifiable rash. After work, I came home to an apartment without air conditioning and often without running water or electricity.

Eventually, though, I learned to work with the macaques, and, by the end of the summer, I had completed dozens of experiments that shed light on their awareness of numerical and physical relationships. When I placed plums in each of two buckets and transferred them back and forth, they consistently chose the bucket with the most food; and when I dropped a grape into a slanted tube, which moved the grape a couple feet to the side, they consistently searched for it directly below the dropping point (stupid monkeys). The fact that no one taught them these behaviors, and parallel evidence from other species, suggest that the causes of these behaviors may, in part, lie in their genes.

The research was exciting, but after two months of it I had to ask myself: What is the value of this kind of science? How would knowing how the mind of a monkey evolved make a difference to the quality of a person's life? What difference would it make to my life, other than the fact that I would have suffered physically to play a stimulating intellectual game?

Evolution and PsychologyTerry Burnham and Jay Phelan are the first scientists I know of to seriously try to answer these questions. In their popular new book, Mean Genes, these lively young scholars attempt to integrate the theory of evolutionary psychology with the practice of living. In essence, they take facts about how the human mind evolved and derive from it advice about how we can improve the quality of our lives.

Questions about how the human mind evolved have been around ever since Charles Darwin presented his theory of natural selection to the world in 1859 with The Origin of Species. Darwin hypothesized about where human thought and emotion came from, but most of the data he had to work with concerned the bodies (not the minds) of distant human relatives like barnacles and finches. At around the same time that Darwin made his great discovery, Gregor Mendel discovered that characteristics were passed from parents to offspring in discrete units called genes. Interestingly, Mendel's theory of genetic inheritance wasn't integrated with Darwin's theory of natural selection until decades after both of their deaths. And it wasn't until 1953 that these discoveries were combined with the discovery of the structure of DNA by James Watson and Francis Crick: genes were then shown to be patterns of DNA that serve as blueprints for the physical traits of organisms.

A few decades later, evolutionary biologists began to seriously consider how genes translate not only into physical traits but also, by extension, into human behavior. In 1975, E. O. Wilson published Sociobiology, in which he attempted to synthesize the social sciences and evolutionary biology, to explain human social behavior with respect to the evolution of our genes. This marked the inception of the interdisciplinary science now known as evolutionary psychology. A year later, Richard Dawkins argued in The Selfish Gene that humans evolved by natural selection to be "robot vehicles blindly programmed to preserve the selfish molecules known as genes" (ix). These genes are "selfish," he argued, in the metaphorical sense that each pattern of DNA has evolved by the standard of self-propagation, even if this propagation occurs at the expense of other genes, of its hosts' lives or happiness, or of the survival of its hosts' society.

Both Dawkins and Wilson (especially in his latest book, Consilience) conclude—on a more positive note—that we can overcome our "selfish" genes and that we will be in the best position to do so if we understand our genetic nature, but neither of them tell us precisely how to do it. Burnham and Phelan, however, pick up where Dawkins and Wilson left off (and not surprisingly, Burnham and Phelan acknowledge both Dawkins and Wilson as having inspired their work [255]).  

It is fortunate that someone has attempted to make this synthesis comprehensively and explicitly, for laymen are more and more often making these syntheses without such guidance as evolutionary psychology becomes increasingly mainstream. People read in the popular media that genes are being discovered every day for everything from sexual orientation to male aggression, and such purported knowledge invariably influences their attitudes and behaviors. Some are more accepting of homosexuality and others are more excusing of violence because of their revised understandings of human nature. But few actually use the conclusions of evolutionary psychology systematically to improve their lives.

THE ANIMAL WITHIN

The Mean Genes approach attempts to do just that. The essence of this approach is simple: "Step 1 is to understand our animal nature, particularly those desires that get us into trouble and can lead to unhappiness. Step 2 is to harness this knowledge so that we can tame our primal instincts" (5-6).

The nature they refer to resides neither in our muscles nor in our sensory organs, but in our brains and minds (they use these two terms interchangeably). However, the fundamental nature of our brains—like the nature of each other body part—is determined by our genes, and our genes have been constructed by millions of years of evolution by natural selection.

Since these genes are "selfish"—in Dawkins's metaphorical sense of the word—they don't "care" about making us live long, happy, healthy lives. It's true that their survival often concords with our survival and happiness, but sometimes the exact opposite is true. Why would natural selection cause our genes to predispose us to do things that make us die young or feel unhappy? (For example, why would we have evolved to enjoy drugs that destroy our health and often, in the long run, our happiness?) There are two primary answers to this question.

First, natural selection tends to cause genes to survive, but not in only one body. In fact, the way genes survive, in the long run, is through the self-replication of bits of DNA (bits of DNA perish with each passing generation, but the DNA patterns that make up genes live on in identical copies of these bits). This is why sex feels good, in the short run, but it doesn't—at least not necessarily and not by itself—lead to long-term happiness. Indeed, the praying mantis male probably experiences the least pleasure of all at the instant when his life is cut short by his mate (though he probably experiences the most pleasure the moment before), who bites off his head and consumes him as they copulate; she then uses his body to nourish their offspring, thereby promoting the survival of his genes while taking his life (182).

Second, natural selection causes our genes to be adapted to a different environment than the one in which we live. Namely, they are adapted to the one in which our distant ancestors lived—evolution is always a few steps behind us. To illustrate, Burnham and Phelan write: "Our brains are built by genes that excelled in a world without money. When it comes to padding our bodies with a bit of fat, we have powerful instincts. Similar instincts for minding our cash haven't had time to evolve" (28). While we would tend to live longer and possibly happier lives if we were innately predisposed to love fat and sugar only in moderation and to automatically plan for our financial futures, they say, these were not problems for our prehistoric ancestors, so these traits have not had time to evolve.

TAKING CHARGE

This is the theory that made Mean Genes possible, but most of the book focuses not on theory, but on practice. In each of ten chapters—one each on debt, fat, drugs, risk, greed, sex roles, beauty, infidelity, family, and conflict and cooperation—Burnham and Phelan synthesize data from the field of evolutionary psychology to explain our animal nature and then tell us how we can overcome this nature, when we need to. "Mean Genes lenses…allow us to predict when we will be weak and why we are vulnerable," they write. "The twig of human nature is indeed bent from the start. It must be seduced, not bullied, into behaving" (11). Evolution has given us a set of incentives that is not always good for us, and in order to improve our lives, they say, we must change the incentive structure.

For example, our brains have evolved such that we enjoy chemicals that tend to shorten our lives (directly or indirectly) and have the potential to make us unhappy. Take nicotine, for instance. Nicotine is found most abundantly in tobacco leaves. Whether or not our ancestors knew about tobacco leaves, they certainly did not "roll 'em up, light 'em up," and inhale their smoke dozens of times every day (they did not even have fire). Our ancestors were not killed by the hazardous chemicals found in cigarettes, and so our species never evolved to have an innate aversion to them. On the other hand, our species has evolved to have an innate affinity for a chemical called dopamine, which Burnham and Phelan call a "happiness neurotransmitter" (67). We are normally rewarded with dopamine when we do things that are generally life-promoting, like eating. However, nicotine mimics a chemical that causes the release of dopamine (among other rewarding neurotransmitters), so we can experience a dopamine high even when we are hurting our bodies with cigarettes. Moreover, biologists have identified genes that cause some people to be more predisposed to nicotine addiction than other people. Burnham and Phelan conclude that because the basis of the desire for nicotine resides in our genes, we can't get rid of it; rather, we have to find other ways to satisfy this desire, and we can start by buying nicotine gum and patches and throwing our toxic cigarettes in the trash.

Most people can appreciate the value of nicotine gum and patches without knowing a thing about natural selection, neurotransmitters, or genes, but there are other psychological hazards that we would neither understand nor know how to overcome as well as we do if we did not have the evolutionary-neurological-genetic approach. Ideally, scientists in this area work together in approximately this fashion: The evolutionary psychologist uses his understanding of human evolution to generate hypotheses about what is innate. The neurologist investigates whether the brain really is as the evolutionary psychologist hypothesizes. And the geneticist tests whether and in what manner the characteristics that the neurologist discovers are innate.

Take risk, for example. Why do so many people risk their lives and their fortunes when the odds are not in their favor? Why do so many people (mostly men) enjoy "extreme" sports, like ultimate fighting and skydiving? Why do so many people throw their money away on lotteries and in casinos? Evolutionary biology, neurology, and genetics have provided new answers to these questions. With these tools, scientists have discovered that some of the answers lie in our genes (which is not to say that there are not non-genetic answers that also help to explain risk-taking behavior). Evolutionary biologists formed the hypothesis that males should have been selected to be more risk-prone than females because—anthropological studies now suggest (88)—the prehistoric men who put themselves in danger relatively often tended to reproduce with the most prehistoric women, and so spread the most genes. Neurologists tested this hypothesis and found that certain risky behaviors led to the release of dopamine, and especially so in men. Moreover, geneticists identified a gene that weakened the effect of dopamine, and found that people with this gene tended toward activities like bungee jumping, race car driving, and high rolling. What implication does this have for how we should live our lives? Burnham and Phelan answer that it is not always best to follow our impulses when risks are involved, especially for those who are particularly risk-prone. "[W]e needn't be suckers in games of risk. To triumph in these uncertain arenas, we must rely on mathematical analysis . . . —not trust our instincts" (100).

These are just two of the many areas in our lives in which our genes will tend to get us into trouble, unless we understand how our "mean genes" push us and how we can combat them. The virtues of this book are embodied in its last lines: "Our temptations are powerful and persistent, but we are not destined to succumb. Ancient and selfish, our mean genes influence us every day in almost every way. But because we can predict their influence, self-knowledge plus discipline can provide a winning strategy in the battle to lead satisfying and moral lives" (252). This goal is admirable and, at a general level, this approach is sound. So many science writers, whether or not their work is intended for a general audience, do not discuss what implications their science has for improving human life. And so many writers of self-help books have little or no scientific basis for their advice. Mean Genes, on the other hand, "is the first book that converts the modern Darwinian revolution into practical steps for better living" (10). "It is not some stuffy academic tome," the authors claim. "Understanding the theory and taking the practical steps we suggest can improve your life" (6). And while it is anything but a stuffy academic tome, it is largely grounded in scientific data. (Don't be fooled by the conversational style and the absence of notes—the notes can be found on the Web, and together they're longer than the text itself.)

The reason these scientists are capable, philosophically, of arguing that we can overcome our genes is that they believe in the existence of something that many scientists do not: free will. Many scientists (including Dawkins) acknowledge the existence of free will in passing, but few invoke it as one of their central premises, as Burnham and Phelan do. In what appears to be a reply to Dawkins, they say that "we are not lumbering robots doomed to carry out our genetic programming. . . . Along with passions, genes have created willpower and the ability to control behavior consciously. With these uniquely human abilities, we can rise above our animal instincts" (5). This theme pervades the book, and other scientists would do well to follow the authors example in this regard.

SLOPPY SCIENCE

While their general approach is good, however, the particular scientific and philosophical manner in which they carry out their synthesis has serious shortcomings: sloppy science and bad philosophy.

These Harvard Ph.Ds aren't the only scholars in their field who practice sloppy science. There is a widespread bias among self-proclaimed evolutionary psychologists to assume that universal human behaviors are products of specialized brain mechanisms that came about by natural selection. Hence we hear scientists claiming that we have a gene for this or an instinct for that without having considered and tested alternative hypotheses that would otherwise explain the data. A few of the more absurd instincts to which Burnham and Phelan refer include "gossipy instincts" (234), "gift-exchanging instincts" (237), and "favor-granting instincts" (239), the existence of which are neither well-defined nor well-supported.

There are three fundamental problems with claims like these. The first is that the authors do not consider alternative explanations. For example, they think that one of the reasons people gamble so much is that we are innately bad at evaluating risk (96), but isn't it also possible that we learn shortcuts for evaluating probability that work in most cases but not in others? (For a good discussion of this issue, see  Kenneth Livingston's Rationality and the Psychology of Abstraction ) Neither hypothesis can be ruled out a priori, but Burnham and Phelan do not even entertain the latter.

The second problem with their evolutionary stories is that many of them are not only unproven but unnecessary. The primary value of evolutionary theory for psychology is that it helps psychologists generate viable, testable hypotheses. When the authors instead rationalize a finding that something is innate, explaining how they think it came about after it has already been discovered, this leaves the reader thinking not only Are you sure? but also So what? While evolutionary stories may be intellectually stimulating for some (just as monkey psychology was for me in Puerto Rico), they are superfluous and distracting in a self-help book unless they are needed to explain how scientists identified something as innate.

The third problem with their claims about instincts is that they are not clear what they mean by instinct. They use this term frequently, but they never define it. Most serious biologists no longer use the term, but instinct has a long history of being defined vaguely or not at all and of being used to sidestep the responsibility of explaining the connection between our genes and our behavior (for a good discussion of the many problems with the term, see Nathaniel Branden's The Psychology of Self-Esteem, 21-27). Are people determined to gossip, give gifts, and grant favors? Obviously not. Then what exactly does it mean to say that people have instincts for these things, and how could we test whether they actually do? No answer. A viable and common alternative is to speak of innate psychological predispositions, which are constraints on how the mind can develop. And it is not enough to merely call something an innate psychological predisposition; to advance a theory about such a predisposition, one must explain precisely how and under what circumstances it is expressed, which Burnham and Phelan do not do. (For further discussion of this issue, see my response to the FAQ "What is the Objectivist view of innate psychological predispositions?" forthcoming on The Objectivist Center's Web site.)

BAD PHILOSOPHY

The problems caused by Burnham and Phelan's sloppy science are compounded by a few false philosophical premises. Most importantly, their conceptions of happiness and self-discipline are mistaken. Their conception of happiness, first of all, is essentially hedonistic. They use the terms "pleasure" and "happiness" interchangeably (for example on page 65). They conclude, "We should enjoy our animal passions and even indulge them but prevent them from controlling us. The key to a satisfying life is finding a middle ground that combines free-flowing pleasure, iron willpower, and the crafty manipulation of ourselves and our situations" (252). They fail to recognize that not all of our passions are "animal passions"—the ones that lead to long-term happiness are distinctly human passions. The fact that people keep working after they strike it rich is evidence to Burnham and Phelan that happiness is not within our reach (113), but only because they don't recognize that many businessmen (at least the happy ones) derive their happiness not from their big houses, cars, and swimming pools, but from the productive work itself.

Their conception of self-discipline is also flawed. They acknowledge that we can overcome our genes, but they underestimate the importance of self-discipline as a way of overcoming temptation, not just diverting it. At every moment, we can choose to exert the effort necessary to grasp reality and to act accordingly, or we can choose to drift along or actively evade the facts we do not wish to face. The most basic ability we use to promote our lives and happiness is our ability to exert effort to control ourselves. When we experience an impulse to do something that is not in our self-interest, the ability we can use to do that which is in our self-interest is self-discipline. But Burnham and Phelan trivialize it by dubbing this self-help strategy "the Arnold approach," after Arnold Schwarzenegger, who became the world's foremost bodybuilder because of his incredible self-discipline. They say, "There is beauty to this approach. We respect discipline. . . . But beyond its sheer difficulty, the Arnold approach has the drawback of continual vigilance" (249). Instead, they suggest we get our "happiness neurotransmitter" fixes from methadone, nicotine patches, and roller coasters. While this may solve a couple of problems, what about the problems we cannot solve with simple substitutions? It is true, as they say, that "[s]ome temptations are better avoided than resisted" (249)—that we must pick our battles. But resisting the temptation to do what is easy rather than what is right is a general-purpose skill whose importance cannot be overestimated, for self-discipline is a prerequisite of virtue.

CONCLUDING QUESTIONS

While Burnham and Phelan have their own philosophical problems to fix, their work does raise some philosophical challenges that need to be answered. First, Mean Genesindicates that man is at war with himself, since his mind (in particular, his capacity to make choices) and his body (in particular, his genes) are in perpetual conflict. Secondly, it suggests that the standard that determines what will make us experience pain and pleasure is not the survival of our selves but the survival of our genes. Thirdly, it implies that temptations for destructive influences are products of genes, not just false premises—if a person is not in focus, he is ruled not just by his subconscious ideas, but also by his animalistic nature. While any of these challenges might imply that some of Objectivism's philosophical premises need to be modified slightly, none of them strikes at the heart of these premises. Mind-body conflict, pleasure not being an indicator of the promotion of life, and temptation not being caused by false premises are clearly not overwhelming problems in our lives—if they were, we would not need specialized scientists like Burnham and Phelan to identify them.

While Mean Genes is somewhat dubious in its particular approach to evolutionary psychology, it should mark the beginning of a tradition of increased confluence between science and self-help. One could benefit from reading this book—but one could benefit even more by starting with a sound scientific framework and a rational philosophy and synthesizing the data on his own. Better yet, he could make this synthesis himself and then produce his own book for the benefit of those of us who are busy fighting battles with more formidable adversaries than our genes.

D. Moskovitz recently graduated from Harvard University and interned at The Atlas Society. For the last three years, he conducted psychological research on non-human primates. Moskovitz's publications include "What Guides a Search for Food That Has Disappeared? Experiments on Cotton-Top Tamarins," which he co-authored with Marc Hauser and which appeared in the Journal of Comparative Psychology, June 2001.

This article was originally published in the October 2001 issue of Navigator magazine, The Atlas Society precursor to The New Individualist.

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