Monday, January 01, 2001

A Little Avuncular Advice from Sociobiology

Mean Genes: From Sex to Money to Food—Taming Our Primal Instincts

By: Lee Alan Dugatkin, Ph.D.

Life as a sociobiologist is a mixed blessing. If you produce a top-notch (and glitzy) study of animal behavior and evolution, New York Times science reporters and other media folk will lavish column inches and air time on your work. If you venture more than a passing remark on what your study may imply for human nature, though, watch out. Few readers or reviewers will be sympathetic; political and ethical blinders will sideline most reasonable discussion. 

That will almost certainly be the fate of Mean Genes, which is a shame, because the many good things the book has to offer will be mired down. I have my problems with Mean Genes, but will try to present them in a logical, step-by-step argument, not a shouting match over biological determinism as a philosophy. 

Before airing my major criticism of Mean Genes, let me state that I am not a neutral observer of the human sociobiology debate. My own work focuses on the evolution of cooperation and altruism, a subject dear to animal behaviorists (ethologists), evolutionary biologists, and sociobiologists with a bent toward human comparisons. I have trod the perilous path from Mean Gene-like arguments about animals to what it all means for Homo sapiens

When I published Cooperation Among Animals: An Evolutionary Perspective (Oxford University Press, 1997), reviews were positive; the book was greeted warmly by most colleagues. Two years later I published Cheating Monkeys and Citizen Bees: The Nature of Cooperation in Animals and Humans (The Free Press, 1999), exploring how animal cooperation might shed light on human cooperation. This time, most reviews were mixed, typically: Loved the part about animal cooperation and evolution, hated the part about humans. Now, it is certainly possible that I just botched the human end of things, but conversations with colleagues suggest that was not why I got mixed reviews. My colleagues simply did not want scientists to make the jump from animal cooperation to human cooperation. 

In light of all this, readers might expect me to look kindly on the notion put forth in Mean Genes: namely, that, throughout our evolution, natural selection has shaped our brains to cope with a hunter-gatherer, small-group world that no longer exists. Many problems in modern life (obesity, greed, marital infidelity) amount to our battle with a brain shaped by mean genes that evolution selected in the distant past. Terry Burnham and Jay Phelan have no shortage of suggestions for how to prevail in this battle. 

To mount their argument, they nicely integrate work in evolutionary biology and animal behavior to establish the premise that “mean genes” and the brains for which they code logically should, and actually do, exist. They then argue that research in human sociobiology is accumulating evidence that this is true not only for animals but for humans. So far, so good. From there, however, the authors move on to specific prescriptions: how we can use mean-gene logic to overcome modern-day woes. This is where my objection arises. 


Consider how Burnham and Phelan handle the issue of diet—more specifically, the problem of overeating. They begin with a solid argument about the evolution of diet preference in humans: In our past, stocking up on fat was a good strategy, thus we have brains that reflect this need. The argument is well supported by evolutionary theory and animal behavior. But as the payoff, at the end of the chapter, the authors feel obliged to present four “problems,” each with a mean gene-based solution. 

Problem: I like to indulge my passions for certain junk foods, but I overeat. For example, I decide to eat some potato chips and buy a big bag, planning to eat just half, but then eat the whole bag. Solution: Open the bag of chips and divide them into two piles. One you will eat and the other you won’t. Destroy the chips you don’t want to eat.… When you throw them away, be sure to make them inedible so that the monster within you won’t be picking through the trash at four in the morning. 

Problem: I plan to eat nothing between lunch and dinner. But in the afternoon I often become very hungry and eat chocolate. Solution: From your overall dietary plan, choose an appropriate snack.… It is unrealistic to believe that you will be able to stay hungry all the time. You have to eat and you are going to eat. Accept this fact but make it easier to eat the foods you choose. 

The other two problems that the authors tackle are similar, as are their solutions. Their goal here (as in almost every chapter) is to use sound evolutionary theory and work in animal and human behavior to provide the reader with concrete suggestions for solving everyday problems. 

I think this approach is risky in general, but particularly risky when you get down to using mean-gene logic to help people fight off the urge to eat potato chips and brownies. 

I think this approach is risky in general, but particularly risky when you get down to using mean-gene logic to help people fight off the urge to eat potato chips and brownies. It gets downright silly when the authors suggest that readers might wish to write the following note on the cupboard: “Dear meaney geney monster. Ha! There are no Ding-Dongs. Eat a rice cake and thank me in the morning.” I understand that levity can be a literary device, but there are limits, and the authors sail past them. Burnham and Phelan use their almost cavalier how-mean-genes-can-help-you-with-everydaylife logic to advise readers on debt, fat, drugs, risk taking, greed, gender, beauty, infidelity, family relations, and friendship. Although the authors know their evolution, they are not experts on any of these practical issues (with the arguable exception of debt and greed, since Burnham teaches at Harvard Business School), and there’s the rub. The conceptual framework of Mean Genes is fine, but making specific suggestions for the gamut of life’s real problems, faced by real people, is another story altogether. 


The reader will have gathered that my position differs from that of the authors on the way work in evolution, genetics, and animal behavior should be used to inform issues of human behavior. I have argued that while it is important to raise a few “thought experiments” on how evolution and animal behavior work might help us understand, and even change, human behavior, generally speaking this is not where such studies are the most powerful. Instead, a thorough understanding of evolution, genetics, and social behavior in animals can unlock a treasure chest of ideas that experts in various human disciplines can incorporate into their own fields. Consider the following example, which I first raised in my book Cheating Monkeys and Citizen Bees

Surprisingly, the costs and benefits associated with a tactic called predator-inspection behavior, used by many species of fish, are strikingly similar to those underlying army guard duty. Furthermore, when interacting with their partners, both guppies and soldiers facing danger tend to use the tit-for-tat strategy. They are nice to those who share the risk (that is, the cooperators), but they punish those who do not (that is, the cheaters). If there are many other animal examples like this, can we use them to understand human cooperation— and, if so, how? As described by Robert Axelrod in The Evolution of Cooperation, we might begin by recognizing that evolutionary theory and empirical work in animals suggest that tit-for-tat cooperation works best when there is a high probability of future interaction among potential cooperators. 

Occupations such as police officer or firefighter jump to mind when I think of long-term human interactions in dangerous venues. It might seem that cooperation among police officers is most easily fostered in partners who have been together for a long time, thus establishing a level of mutual comfort. Evolutionary theory and work in animal behavior, however, suggest that it is not so much past experience as the probability of future interaction that breeds cooperation. Tit-for-tat cooperation succeeds not because of a long series of past interactions (in fact, only the last interaction matters for this strategy), but because of the possibility of many chances to reap the benefits of cooperation in the future. 

Can this distinction between long-term bonds that focus on the past versus the future possibility of interaction really be useful? Could it be used to decide how to pair up police officers? I do not know. But people in law enforcement may know and perhaps, just perhaps, can incorporate this insight from sociobiology into their toolkit. That is their job, however, not mine. It may do no harm for me to make an occasional suggestion to these experts about human applications, but that is as far as it should go. 

In dispensing direct advice to the reader, Burnham and Phelan cross the line—often, and with zest. Looking back, I too have stepped over this line. Occasionally, I have let down my guard and provided specific suggestions about how to use animal work and evolutionary thinking, perhaps without making it clear that this information should be evaluated first by experts in human fields. I now regret that. For Burnham and Phelan, specific how-to-leadyour-life ideas emerge directly from a mean-genes world view. I respect their gumption, but I see this as a serious misstep for the field of sociobiology. 


Perhaps discussions of overeating, greed, and most other topics covered in Mean Genes are not particularly dangerous. Perhaps we should not worry if two obviously bright guys throw out some ideas, good or bad. These are reasonable positions to take if we focus just on the issues addressed in Mean Genes, but what other issues might a mean-genes view address down the road? Should sociobiologists be tossing around how-to lists when it comes to mean genes and murder? Xenophobia? War (mentioned very briefly in Mean Genes)? Infanticide? These have been as much a part of our evolutionary history as a craving for fat, so the mean-genes approach should have some prescriptions to offer our hunter-gatherer brains, shouldn’t it? But should those with training in evolution and animal behavior, but not in murder, xenophobia, war, or infanticide, be making the suggestions? That prospect rings my alarm bells—and I noticed that when the authors speak of politically charged matters, like homosexuality, they abruptly change the brisk problem-solution style to one that is much more cautious. 

Rather than the approach adopted in Mean Genes, I suggest that after evolutionary biologists and ethologists have explored some important area, they communicate their ideas to a variety of experts in that area—the more experts the better, to avoid favoring a particular political agenda. We should hope that these experts then mull over what they have been given. Perhaps all parties would sit down and discuss how to use the information to the greatest benefit. Sometimes that will mean presenting the public with general suggestions; sometimes it will end with evolutionary biologists, ethologists, and public policy people admitting that they are not sure what to do. That admission should not be viewed as a failure. It is a natural consequence of addressing difficult issues from different perspectives. If my recommended approach worked even one time out of four, I would consider it a huge success. 

I agree completely with Burnham and Phelan’s lament that “to better understand ourselves and our world, we need to look not to Sigmund Freud but rather Charles Darwin.”  Ironically, however, I find myself giving Mean Genes the same sort of author-frustrating review I received when I went from animal sociobiology to human sociobiology. I found the ideas on evolution and behavior in nonhumans a good and informative read, but the suggestions on what all this means for understanding human behavior are problematic.


From Mean Genes by Terry Burnham and Jay Phelan. ©2000 by Terry Burnham and Jay Phelan. Reprinted with permission of Perseus Books. 

Mean Genes seeks to offer a better understanding of human existence, drawing from diverse disciplines and hundreds of sources. We garner insights, for example, by looking at a range of cultures, including many that are worlds apart from our own. We also learn about humans by studying animals ranging from our close genetic cousins, the chimpanzees, to mice and even fruit flies. But the foundation of the book is evolutionary biology. 

Ever since Darwin published The Origin of Species in 1859, people have debated the role of biology in human affairs. Still, as the idea of evolution has itself evolved, one provocative facet has become clearer and clearer: the human brain has been shaped by evolution. From its tremendous size right down to the mechanisms by which individual neurons talk to each other, our brain—like our eyes, arms, legs, and kidneys—is a product of natural selection. We know this is true. Does it follow that our psyches, too, have been shaped by evolution? 

We think so, but not everyone agrees. Some mock the idea; others are troubled or even angered by it. But volumes of research have begun to quiet the critics. The more progress that is made in unraveling the genes we carry, the more clear it becomes that our evolutionary inheritance plays a central role in our lives. 

Are genes the whole story? Obviously not. Other factors are important in determining every human characteristic. We know, for example, that physical or emotional abuse can scar children, regardless of their genetic endowment. Similarly, while we each inherit a particular genetic risk for heart disease, lifestyle decisions affect our health dramatically. 

In this book we focus primarily on the genetic role. Many other books describe the cultural influences on the behaviors we address, and we encourage you to study the ways that genetic and environmental factors interact to shape our lives. 

Being full-time academics, we read hundreds of obscure research articles each year. We attend conferences and eagerly line up for talks with such titles as “The Phylogeny of New World Monkeys” and “DNA Damage— Induced Activation of p53 by the Checkpoint Kinase Chk2.” We debate with other scientists on the front lines, discussing breaking studies long before the information hits the New York Times and other media. 

Most people don’t spend their lives similarly immersed in scientific detail. But everyone can benefit from the knowledge about human nature that has incrementally— and relentlessly—piled up during the last forty years, a period known as the second Darwinian revolution. This knowledge has changed our lives. And we think it can help you live a rich and passionate life without self-destruction. Think of us as your translators, bringing the crucial information from the frontiers right into your living room.

About Cerebrum

Bill Glovin, editor
Carolyn Asbury, Ph.D., consultant

Scientific Advisory Board
Joseph T. Coyle, M.D., Harvard Medical School
Pierre J. Magistretti, M.D., Ph.D., University of Lausanne Medical School and Hospital
Helen Mayberg, M.D., Icahn School of Medicine at Mount Sinai 
Bruce S. McEwen, Ph.D., The Rockefeller University
Donald Price, M.D., The Johns Hopkins University School of Medicine
Charles Zorumski, M.D., Washington University School of Medicine

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