Reviews

Book review: No Two Alike

Posted on by Mary / 2 Comments

I just finished reading Judith Rich Harris’s new book No Two Alike: Human Nature and Human Individuality. Harris is an independent scholar whose controversial The Nurture Assumption: Why Children Turn Out the Way They Do, published in 1998, proposed that based on the evidence, it doesn’t appear that parenting styles have much to do with how kids turn out.

No Two Alike follows up on The Nurture Assumption to some degree by investigating the question of what it is that drives the personality differences between individuals. Even identical twins (with their shared genes) who are reared in the same household differ from one another; Harris takes as an extreme case a pair of conjoined twins who were definitely quite distinct personalities.

I enjoyed reading this book; Harris has a conversational and engaging style that nonetheless manages to convey quite a bit of information clearly. This book gave me a better understanding of how evolutionary psychology works (i.e., how a hypothesis can be proven or disproven) better than anything else I’ve read so far. Perhaps this is because she focuses not so much on imagined scenarios of Paleolithic life, but on questions like “If a mental system worked like this, how would we expect people to behave, and how can we test whether they do behave that way (and rule out other explanations)?” I’m really encouraged, by the way, by how much Harris has been able to accomplish as an independent scholar. I liked her story about receiving an award named for the guy at Harvard who had written the letter many years before that rejected her as a Harvard grad student.

Harris uses the metaphor of a mystery story to structure her search for the causes of individual differences. She begins by methodically and thoroughly investigating five red herrings that could explain individual differences but in fact do not. Her analysis includes some eye-opening investigations of work that has seeped into the popular press in a distorted form. I had heard of Stephen Suomi’s research that supposedly showed that high-reactive (anxious, fearful) monkeys can become confident, even high-status individuals if they are raised by a low-reactive (calm) mother, which certainly seems to support the idea that parenting influences personality. However, Harris dug deep to try to find details about this research and found only what she described as the scientific analog of vaporware. She dissects some other work that has gone unquestioned into the media, with similar results.

Then with the stage cleared, Harris begins describing her model for three mental mechanisms that together could cause and perhaps even strengthen differences between people. The relationship mechanism evolved to help us manage our interactions with other individuals. It discriminates between different people and helps us deal with each separate relationship appropriately. The socialization system helps us to learn the customs, language, and attitudes that are considered appropriate for the groups of people to which we belong. This system relies more on averages and generalizations. One thing I noted is Harris’s observation that children are socialized by people outside the immediate family, the ones they will have to spend their adulthood with. I had always thought it a little strange that of myself and my six siblings, none of us is a practicing Catholic or even, as far as I know, attends any church at all regularly, despite the fact that my parents raised us in a devoutly Catholic home. But it makes sense that we would learn to fit into the outside world where we have to live our lives now, which is quite different from the religious milieu in which we grew up.

The status system tells us where we stand in the hierarchies and groupings of the society we live in, so that we can figure out our relative strengths and weaknesses and how we can best compete with others. We learn from how others treat us, and to some degree we use our skills at understanding what others are thinking to gauge their reactions to us and form a mental self-image accordingly, so that we can shape our behavior based on what we learn. (E.g., if people tell me “Don’t quit your day job” when I sing or tell jokes, I’ve learned something about how I measure up in my ability to entertain others.)

I liked Harris’s observation that the socialization system and the status system have different motivations (to be like everyone else and to be better than everyone else respectively). This is one of the central conflicts of being human, and it was interesting to see it in the context of a discussion of how we grow into the people we are.

As Harris explains it, the status system is at the heart of the process that leads to individual differences. Our relationships with others, which feed information into our status systems, are based on who we are as individuals, so even identical twins do not get quite the same feedback from the people with whom they interact. The small differences that allow people to tell the twins apart also enable them to treat the twins differently, and of course the same process works for ordinary siblings, who are easier to tell apart. These differences in feedback from the outside world would cause the status system to devise a slightly different competition strategy for each person. Furthermore, random events can cause a systematic change in how we behave if they affect how people see us; also, even minor differences in status in a group can widen an initially small difference in behavior and personality. Only one person can be the brightest or prettiest or strongest or funniest, for example, so if you can’t quite fill that role in a group, you may seek another role.

The evidence Harris produces to support the existence of these three mechanisms is not only persuasive but fascinating to read. She goes into a lot of details about how children are socialized and some of the submodules that the three systems use, and this gets into some aspects of memory and cognition (e.g., how the brain forms and uses categories). She closes the book with a little speculation about why we need consciousness and the role that individual differences play in the division of labor in human societies, which she describes as an emergent property of human groups. She also suggests some ways her hypothesis might be tested; I suspect she’s right when she says that it will probably wind up being even more complicated and nuanced than the picture she presents here. I hope that people follow up on her suggestions.

Thinking Meat Project

Happy memories

Posted on by Mary

To some extent, who we are is who we remember being. (I am crudely paraphrasing someone, I think John Locke.) A couple of researchers at Concordia University recently completed a study of the way important life events define a person’s sense of self, and how the emotions that accompany these events change over time (how people felt at the time of the event compared to how they feel about it when they recollect it later). This article from WebMD describes the study in some detail, and this one from ABC News puts the story in the context of other research. When people look back at something that had great importance for them, their pleasant memories are stronger and their painful memories milder, compared to what they say they felt at the time. One goal of the study was to examine the relationship between self and autobiographical memory. Your memories of important events in your life contribute to your sense of who you are, and perhaps the bias toward remembering the positive emotions and letting the negative emotions fade with time helps us build and maintain a positive image of what our lives are about.

The ABC News story describes work by another researcher who found something similar; people recalled more happy times than they did sad times, and the pleasant memories tended to linger longer than the unpleasant ones. The exception, interestingly, is that depressed people had about equally good recall of both good and bad times. I wonder if this is related to depressive realism (the hypothesis that depressed people tend to make more realistic judgments of their own abilities and strengths).

The average age of participants in the Concordia study was mid-20s; I wonder how old the people were in the other studies that the ABC News article mentions. Older people have had more time for their painful memories to mellow or otherwise shift. Part of what’s going on might be a mental mechanism for keeping a positive attitude toward our lives, but part of it might also be that as time goes by and you gain more knowledge of all the ramifications of an event, you can see benefits that you couldn’t see when it was upon you in all its misery. I don’t remember where this quote came from, but Garrison Keillor once said:

“Some luck lies in not getting what you thought you wanted but getting what you have, which once you have got it you may be smart enough to see is what you would have wanted had you known.”

Some things, of course, you never would have wanted, like the death of someone close to you. But even then you may find that something is more endurable than you thought it might be. C.S. Lewis, writing in A Grief Observed about the death of his wife, said:

“One never meets just Cancer, or War, or Unhappiness (or Happiness). One only meets each hour or moment that comes. All manner of ups and downs. Many bad spots in our best times, many good ones in our worst. One never gets the total impact of what we call “the thing itself”. But we call it wrongly. The thing itself is simply all these ups and downs: the rest is a name or an idea.”

Maybe with the passing of time it’s easier to realize this.

Thinking Meat Project

Earliest memories

Posted on by Mary

My earliest memory goes back to when I was three years old and my parents brought my little sister home from the hospital (at least that’s the earliest one I can reliably pin a date on). But if I’d grown up in a different kind of culture, my first memory might well fall earlier or later in my life. This article from the American Psychological Association says that the average age for the earliest memory a person has depends on the value placed on individual experience and memory in that person’s culture. The more a culture values the past (individual or joint) and the sharing of personal memories, the farther back in childhood a person is likely to remember. In America, we value our unique personal histories, and we typically remember back to when we were around 3 1/2 years old. In Maori New Zealand culture, which emphasizes a shared past to a greater degree, people remember back to earlier ages than we do, on average. By contrast, in Asian cultures people tend to have a later first memory. It’s not a function of how good a memory you have; it’s got to do with how much you hear others talking about events and their memories of them, and how people speak of their memories (cultures differ in how much detail is generally given when people are telling their personal stories or discussing events). If you live in a society where people share their personal narratives in greater detail, you need to have your own memories to bring to interactions with others. I’m intrigued by this glimpse into the way the inner world works differently in other cultures.

Reviews

Book review: On Desire

Posted on by Mary / 1 Comment

I recently read On Desire: Why We Want What We Want, by William B. Irvine. The subject is related to happiness, because getting (or not getting) what we want or think we want changes how we feel about life. Roughly the first half to two-thirds of the book is an examination of how desire works, from a psychological and evolutionary point of view. Irvine discusses the role of emotion and intellect in desire and decision-making; he talks about the unconscious origins of many desires, for example. I’m fascinated by the role that unconscious processing plays in our lives, so I was interested in this Bertrand Russell quote:

“…the discovery of our own motives can only be made by the same process by which we discover other people’s, namely, the process of observing our actions and inferring the desire which could prompt them.”

I’m intrigued by the idea that to some extent we don’t really know all that’s going on in our minds and have to watch our own behavior to see what it is we really want. This jibes with the idea that when mental processing occurs outside of conscious awareness, our conscious selves will make up some kind of story to explain the results. (See, for example, Michael Gazzaniga’s interpreter theory.) Russell’s point was that we lie to ourselves about what we want, even going so far as to develop false belief systems to kid ourselves.

Irvine emphasizes that emotion is crucial to desire. The intellect can form desires on its own (I can decide to raise my right arm for no particular reason, for example) but those desires don’t have anything like the power of desires based on feelings. The role of the intellect is mainly to figure out ways to satisfy desires that come from the emotions. (Irvine says that’s not just the role of the intellect in desire; that’s the reason the intellect developed in the first place: not so we can rise above our biological urges, but so we can more effectively fulfill them.) And while we may have a hard time dealing with our emotions and the yearnings that they inspire, these yearnings are what give us direction, define our goals, and give meaning to our lives.

The problem for most of us comes from the way we are apparently wired to want things that won’t actually make us happy (as Levine puts it, to “miswant”), and from the way we adapt to the good things we have so that they no longer satisfy us as much as they did when we first got them. Levine talks about the evolutionary history that might be behind this, and also about our biological incentive systems, or BISes, which reward us for doing things that enhance our chances for survival and reproduction, and punish us for doing things detrimental to our chances.

I particularly enjoyed Irvine’s speculations about how the BIS shapes human nature, and whether slight differences in each individual’s BIS are the basis of personality differences. (E.g., extroverts might have BISes that are quicker to provide pleasant feelings when they interact with others and unpleasant feelings when they don’t, whereas introverts gain more pleasure from solitude.) This says something about the limits people will run into in trying to change their preferred behavior.

The human BIS is not perfect; in particular, we can cheat the system (e.g., certain drugs will give us a reward that we didn’t earn) and the rules are out of date (the reward for eating fatty and sweet foods likely made more sense when food was harder to come by). The imperfections make it hard for us to live peacefully with our BISes. Irvine says:

This, in a nutshell, is the human condition: because we have a BIS, we are forced to live under an incentive system that we did not devise, that we cannot escape, and whose incentives not only aren’t calculated to induce us to have happy, meaningful lives but will, if we respond to them, keep us in a state of dissatisfaction.

So in roughly the last half of the book, he discusses a number of different approaches to dealing with desire: religious (focusing mainly on Christianity and Buddhism, as I recall), philosophical (e.g., Stoicism, Epicureanism), and what he calls eccentric (espoused by individuals like Thoreau, for example). He does a decent job of discussing prayer, meditation, and specific thoughts and behaviors that people have used to handle their desires, and he talks about a few desires in particular—how some religious communities deal with sexual desire or greed for property. Overall, though, I was disappointed in this section of the book. Irvine talked mostly about how people deal with a desire once they believe that it is harmful for some reason, and I was hoping for more about how people decide which desires to follow and which to deny. He says at one point that life is about more than just doing whatever your BIS tells you to do, and certainly endless license is no recipe for happiness. (I recently read Tom Wolfe’s latest, I Am Charlotte Simmons, and his descriptions of young people heedlessly following wherever their BISes take them does not make a pretty picture.)

On the other hand, there are evolutionary reasons for our desires, and if they are the thing that gives life meaning, as Irvine says earlier in the book, then what I’m most interested in is the subtle, shifting balance between enjoying the pleasures that are to be found in being human, and protecting our long-term interests by using those pleasures intelligently. I wish there had been more about that in this book, but all in all, I enjoyed it and picked up some interesting new ideas from it. It’s not a self-help book by any means, but it does contain some advice for dealing with desire; the advice is generic enough that putting it into practice takes some thought, so perhaps the biggest contribution to happiness that this book can make is increasing our understanding of how our desires work—as the subtitle says, understanding “why we want what we want.”

Thinking Meat Project

The scientific study of happiness

Posted on by Mary

Edge has recently posted an essay by Daniel Gilbert, a researcher whose subject is happiness. Among other things, Gilbert talks about why the study of happiness can be just as quantitiatve as other sciences (e.g., the science of vision) that rely on people’s reports of their experience, and talks about how a qualitative study of happiness might help us to understand our emotional experience. I’m intrigued by the analogies he draws with previous scientific breakthroughs.

Gilbert has just written a book about happiness, the latest of many happiness books that have appeared in the last few years. Yesterday I picked up two books at the library about happiness: a history of the concept by Darrin M. McMahon, and a novel by Lisa Grunwald about a woman who’s trying to write a history of happiness while exploring its meaning in her own life.

Thinking Meat Project

Knowing what will make you happy

Posted on by Mary

I’m in the process of buying a house, which is why I’ve been blogging a little less frequently. This week the house was inspected and a major problem found, and yesterday I had to decide how to respond to the seller. It was a difficult decision that I had to make under time pressure with inadequate information; I hated having to make it. My choices boiled down to asking for more money to fix it, and risking losing the deal, or asking less money and risking having to put up a lot more of my own money to fix the problem. I went with the latter, and am, predictably enough, agonizing now about the what-ifs involved (if I had gone the other way it would be a different mental anguish).

So a recent article about Daniel Gilbert’s research on happiness caught my eye because it opened with an example about buying houses. The standard real estate advice is to buy the least desirable house in the best neighborhood, which might be sound financial advice, but not a guide to being happy. Because we make comparisons between what we’ve got and what the others have got, the potential for unhappiness in a lesser house surrounded by nicer ones is great. The article went on to talk about how often we incorrectly predict what will make us happy or unhappy. There was some advice at the end about how to tell whether a decision will really make you happy: look to other people. For example, if you think you’ll be happier if you have a child, look at the parents around you and see if they’re happier. But people overestimate their own uniqueness and so tend to undervalue this method.

Yesterday when I was trying to figure out how much money to ask the sellers for, I took into account how much I thought the repairs might cost, based on the incomplete information I had, how much I could afford to pay myself if I had to, the likelihood of the seller having a backup offer, and the condition of the house otherwise. I tried to be as rational as I could. But there were significant gaps in my information, and I also had to use an emotional calculus: of the most likely outcomes, which is going to make me most unhappy? Am I going to feel worse over losing the house to another buyer, or over having to pay $1000 or so more to get into the house than I thought? According to this article, for most bad things (or good things, for that matter) that happen to us, we adjust afterward and they don’t have a long-term effect on our happiness. So maybe I’ll be OK no matter what happens. But I’m still on pins and needles until I know how it all turns out.

Thinking Meat Project

The third culture

Posted on by Mary

This essay from The Edge examines the prospects for the emergence of a third culture in which the natural sciences join the humanities in explaining why we feel and behave the way we do. The “third culture” concept refers to C.P. Snow’s essay The Two Cultures, based on a 1959 lecture, in which he discussed the problems resulting from a lack of communication between humanists and scientists. The Edge essay, by philosopher Gloria Origgi, talks about some of the possible pitfalls of using the natural sciences in explanations of human behavior, and also mentions some work that avoids these pitfalls and perhaps exemplifies what we might hope for from a third culture. Using biology, in particular evolutionary biology, to help figure out human behavior (why we love who we do, why we tend to have certain kinds of social institutions but not others, why we believe in gods) has been a contentious enterprise, but I find it a fascinating one, and I hope we do see more integration of the sciences and the humanities.

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The love of unseen things that do not die

Posted on by Mary / 0 Comment

Late Thursday night, five singers, students at IU’s Jacobs School of Music, were killed when their plane crashed coming into Bloomington’s airport. It’s a terrible loss not only for their family and friends, but for all those who knew them at the music school. The students were bright and talented and full of promise; I had heard several of them sing in various productions here, and one of them, Robert Samels, was familiar to me as a voice on IU’s public radio station, an announcer and the producer and host of an excellent weekly show about vocal music. I am not formally connected with the music school, but I spend plenty of time at concerts here and feel like a distant member of the music school family that has suffered this loss. The young people were all similar in age to my sons, and my heart goes out to their parents. (My sister once said of parenthood that it was 18 years of worry, but in fact you are always vulnerable to that unimaginably horrible phone call.)

This evening the music school is going to perform Beethoven’s Ninth Symphony, with its stirring choral ode to joy. I had been looking forward to the performance, and two of the students who were killed in the crash were going to be part of the chorus. My first reaction after the crash was that this joyful music would be as jarring right now as the cruelly lovely April weather we are having this weekend. I had no heart for such a thing, but still it seemed important to go. I remember September of 2001, when the Lotus World Music Festival came less than two weeks after the 9/11 attacks. I felt similarly heartsick then and almost decided not to go. But in the end I went and was glad I did; for one thing, I didn’t want for Bloomington to be collectively terrorized into losing this wonderful mingling of world cultures. I didn’t want the bad guys to win that one. But this is different; there are no bad guys, other than the immutable fact that all we hold dear is painfully transient and fragile.

I’m not the only one who thinks this performance tonight is important, though; it will be offered as a tribute to the five young people who have died, and I’ve heard that additional singers are asking to participate so that they can also be part of the tribute. I expect it will be a powerfully emotional performance. One of the things that draws together the people at the university and in Bloomington who value all the wonderful live music we have here is, I think, expressed in the phrase “the love of unseen things that do not die.” (The quote is from an inscription in a lecture hall at Princeton, and is attributed to Princeton alumnus H. E. Mierow.) That’s why the concert tonight is important. Despite, or maybe even because of, everyone’s grief at the loss of these five students, it’s important that the music they loved will continue.

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Turning off the self

Posted on by Mary / 0 Comment

When I read Sam Harris’s The End of Faith recently, I was struck by some of the things he said about meditation and consciousness, like the following:

“Meditation,” in the sense that I use it here, refers to any means whereby our sense of “self”—of subject/object dualism in perception and cognition—can be made to vanish, while consciousness remains vividly aware of the continuum of experience.

Some recent research seems to have located a part of the brain involved in accessing that sense of self during introspection, and even watched that part of the brain go quiet when people were intensely engaged in processing sensory input. Researchers used fMRI (functional magnetic resonance imaging) to scan the brains of people who were performing two tasks, one requiring that they focus on the characteristics of either an image or a piece of music, and the other requiring that they focus on their own feelings about the image or the music. Different brain areas were involved in these two tasks; furthermore, when people were most intent on the sensory task, the part of the brain active in the self-evaluative task was quiet. There are some interesting parallels here with what Harris said about meditation. I’m intrigued by this look into what goes on in the brain during moments of absorption in what is going on around us rather than our reaction to it. A friend of mine recently told me that one reason people enjoy physically demanding activities like rock-climbing is that you have to pay such close attention what you’re doing that there’s no room for worry or depression in your mind. I’m not going to take up rock-climbing, but I think that kind of absorption might be similar to what I find in playing the piano.

http://www.eurekalert.org/pub_releases/2006-04/cp-wtb041406.php

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Explaining female orgasm: An interview with Elisabeth Lloyd

Posted on by Mary / 0 Comment

In The Case of the Female Orgasm: Bias in the Science of Evolution, Elisabeth Lloyd (Arnold and Maxine Tanis Chair of History and Philosophy of Science and Professor of Biology at Indiana University, Bloomington) examined the data supporting the 21 evolutionary explanations for the origin of female orgasm. She concluded that the evidence as it currently stands best supports the hypothesis that female orgasm is not an adaptation, but a byproduct of embryological development and the adaptiveness of orgasm in the male, and that there is inadequate evidence to support any of the hypotheses indicating that female orgasm is an adaptation. The book has generated a great deal of response from feminists as well as scientists. Prof. Lloyd spoke with Thinking Meat in April 2006.

TM: Did you expect the book to get the reaction it did?

EL: Oh, no. Several people had warned me; a couple of my friends had a much better idea than I did that I would run into some of the problems that I did run into. I was expecting the objections from evolutionary adaptationists (for example, the reaction from David Barash, although I didn’t anticipate that it would be quite so ad hominem. I would like to note, however, that David Barash very generously arranged the unique opportunity for my rebuttal—which is posted on my web site—to be linked to directly within the journal Evolutionary Psychology immediately following his highly critical review), because the book did show that at least on this occasion, pursuing an adaptationist program single-mindedly led to pretty deficient science.

What I didn’t anticipate at all was the feminist backlash, because I’ve been a feminist since I was 20 years old, and the book offers a feminist analysis. My friends warned me that it would be misread and misinterpreted, and that some feminists would take the point of view that I was promoting a male model of female orgasm, that is, that the byproduct account is somehow male in essence because it says female orgasm is derived from the selected male orgasm. But that’s “derived from” in only the most trivial sense. It says only that male orgasm is adaptive; it doesn’t mean “derived from” in any metaphysical, meaningful, cultural sense. I mean, we don’t care what’s adapted or a byproduct in real life and in culture; most of the important traits that we care about in society are byproducts. Most of the functions of the brain, the things we do in everyday life, like reading and writing and using a computer and going to the opera, these are all byproducts, and we don’t care about whether they’re byproducts or not. So I guess I didn’t really believe that anyone would misunderstand the theory so profoundly to take me to task for it, especially feminists, since I was a feminist. But a couple of friends of mine who anticipated that that would happen were absolutely right, and it was a very vicious set of reactions. It caught me completely off guard; I was absolutely stunned.

TM: What surprised me was that it came from two different directions which logically couldn’t both be right.

EL: I couldn’t win for losing; one side said I was overly influenced by my ideological beliefs to make a scientific conclusion, and the other one said that I was overly influenced by my science to make an ideologically incorrect conclusion. But both of those perspectives are actually wrong. You can understand why the adaptationists would get paranoid, because they look at what I did, which is to take the 20 adaptive explanations of female orgasm and find every one at fault, and they say, “She was out to get adaptationist explanations, she had an agenda. She went out and said: I’m going to show that every one of these evolutionary explanations for female orgasm is wrong.” That’s one way to think about why it is that I ended up saying that every explanation turned out to be deficient in its evidence. But the other obvious explanation for why I came to the conclusion I did was that I approached every explanation individually and examined it and used the ordinary standards of evidence for evolutionary explanations and found independently that each one was deficient, which is in fact what happened.

When I first started looking at female orgasm, I was trying to answer this question for a friend, who had asked me, “What’s the function of female orgasm?” I assumed it was an adaptation, so I wasn’t on the warpath at all. But I was struck by how the explanations that I found conflicted with what I knew about the sex literature. They seemed evidentially deficient on their faces, so I thought, oh, these aren’t very good adaptive explanations, and so the ball started rolling…I went in assuming it was an adaptation and ended up thinking it wasn’t; it’s not that I set out to show that it wasn’t an adaptation. They just made that up; it’s pure fantasy!

TM: Do you think they might be defensive, because some of these hypotheses seem surprisingly poorly supported, and they’re wondering why they didn’t ask these questions themselves?

EL: In the last few years that I was researching the book I kept getting told again and again that it had been proved that female orgasm was an adaptation, and I’d better damn well go back and look at that uterine upsuck evidence. [The uterine upsuck hypothesis is that orgasm aids in conception by causing contractions that suck sperm into the uterus.] And I went over that stuff with a fine-tooth comb; you can see my analysis in chapter 7. I found what I found, which was a sort of smoke and mirrors with very shoddy statistical evidence, which does not pass muster for even the most primitive statistical standards of any scientific journal that I have run across. And so far even my worst critics agree with me about that.

So, yeah, I imagine there would be a certain degree of embarrassment about this, because this stuff has been taught all over the world as fact, for the last twelve years. I cite more than half a dozen publications in my book which deliver it as the uncontested fact of the matter about the evolution of female orgasm. Now the fact that it turns out, on closer inspection, to be little more than speculation at this point in time, would I think naturally be an embarrassment to the evolutionary community, because it’s evidence of a failure of self-policing. When they were writing that female orgasm was an adaptation and that it was in fact this type of adaptation, there was a competitive explanation that it was a byproduct that was well supported by evidence and that they had dismissed out of hand. They claimed that in contrast this other explanation was well supported. That turned out to be not true. As a result, they ended up delivering a story—a fable—about the state of the evidence, and in fact, a fable about the evolutionary standing of female orgasm to all their students over twelve years all around the world. That’s a lot to be responsible for. So it isn’t just that they said the one thing was a fact, it’s that they also said that the other thing, the byproduct view, was wrong. And what that means is that they’ve said it exactly backwards: The byproduct view has the evidence; the upsuck view does not have the evidence. That’s a serious thing in my book. So yeah, I think that they have something to answer to, and I think that if they are embarrassed they should be, and if they’re not, they should be starting to be embarrassed.

TM: So why do some people believe so strongly that most traits are adaptations—why are they adaptationists?

EL: I think the best thing to do would be to ask them why they’re adaptationists. I don’t know why they’re adaptationists. I would like to know, for example, why John Alcock thinks what he thinks, very much, in fact. He has a well-documented, savage, and implacable hatred of Stephen Jay Gould that was sort of manifested in this discussion of female orgasm. It made it very nice for me in my discussions and exploration of the literature, because he wrote so much about it. But that might have contributed to his making some claims that might be considered ill judged on the evidence.

There’s something really, really exciting when you realize how natural selection works to shape and create mechanisms that contribute to the reproductive success of organisms. The power of the combination of random mutations and selection to produce such creativity, the power of creativity is so mind-boggling that many a researcher, I think, is captivated for life by that, and pursues the mission of looking at the natural world in those terms, which is an understandable and admirable way to approach things. A problem with that is that we know that evolutionary processes involve more than mutation and selection, and in particular more than selection processes. Evolutionary change involves historical and developmental processes as well, and of course all of these are also shaped by selection over time, so there is a very complex interaction. But the interaction of, for example, selection and development, and selection and history, is something that may not be as exciting. To get inside the adaptationists, though, I think you’d need to ask a self-styled ardent adaptationist like John Alcock or David Barash.

TM: After all, it’s not like evolution created human beings out of nothing; it had to work with what was there.

EL: One of the most common confusions I’ve run across with the book, and I was discussing this recently with Frans de Waal, is that people have gotten confused about the evolution of the clitoris in terms of its role in sexual excitement. Donald Symons since 1979 and Gould and I have always been very clear that it’s adaptive in its role as producer of sexual excitement and trigger for the variety of responses that are involved in preparing for sexual intercourse (for example, keying up the changes in vaginal length and increased lubrication and so forth, and sexual interest in intercourse), all of which are clearly adaptive. What we claim is that it’s not adaptive in the very specific function of producing the spinal reflex of orgasm itself, which is only one of the many possible reactions that the clitoral physiology can be involved in. It’s perfectly clear that the role of the clitoris in all these other things, sexual excitement, lubrication, etc., is adaptive and there would be plenty of selection for the clitoris in all of those functions, and therefore selection for it and maintenance in that role. It’s just that there’s no evidence for its selection for the reflex. It’s never been correlated with fitness; there’s no evidence for design; there’s no evidence for function; it’s not correlated with anything that we know of.

TM: I like the list at the very beginning of the book of characteristics that a trait must have to be an adaptation. To my mind that would be a good thing for the average reader to keep in mind when reading evolutionary explanations for human behavior in the media. Particularly for anything related to sex, it seems like a very hard area to be well-informed in.

EL: There’s some really interesting possibilities with the uterine upsuck. I mean the Baker and Bellis research, because of the statistical problems, and because of the logic of their own account, which is self-defeating, is kind of in a ditch. But there are a couple of new studies that came out this year that you might have seen about the heritability of female orgasm. One of them was by Kate M. Dunn et al.; the other one was by Khytam Dawood, a researcher out of the University of Chicago. There was a big twin study cohort and she and her group found that female orgasm was moderately heritable. There’s all kinds of things to say about that; I’ve discussed it in my blog contributions. Female orgasm and female orgasmic capacity is so very highly variable among women; you have some women who are very highly orgasmic in a number of different situations, with intercourse, outside of intercourse, with masturbation. And then you have quite a few women at the middle of the pack where sometimes they have orgasm and sometimes they don’t; it depends on the situation and it’s much tougher for them. And then you have a large set of women who really don’t have orgasm that often in their lives; maybe they have, I don’t know, 500 orgasms in their lives, and then you have another set that have maybe 20 orgasms in their lives, and then you have 5 to 10% of women, maybe more, who never have orgasms in their lives, ever. That’s a very big chunk of women who never have orgasms in their lives, if you’re going to consider orgasm an adaptation. This is kind of a problem.

At any rate, if you look at all the different samples of women that people have studied over the years (I summarize 32 studies in my book), if you look at, for example, Dawood’s new study or Dunn’s new study, this just confirms the kind of flat distribution of this variety. You get this picture of women that they just come in all these different varieties of orgasmic capacity, whether it’s with intercourse or whether it’s just in terms of orgasmic capacity altogether, and this is everything that we’ve learned from the sexology over the years. This poses a very difficult problem for anyone who wants to give an evolutionary account, because what it basically means is that you can’t just give one. A favorite one these days says that women have orgasm during sex “when it’s with a high-quality male”. But women who only have orgasm with a high-quality male, well, they have to be women who sometimes do and sometimes don’t have orgasm with intercourse. Maximally, that includes about 35% of women, so that’s a minority of women. And that’s a problem, because all the women who always have orgasm with intercourse, they’re not included, and all the women who rarely or never have orgasm with intercourse, they’re not included. So that’s 20% plus 34%, so 54%, of women who aren’t included in the hypothesis. If you’re going to have a hypothesis that includes only a minority of women in it, you need to have a separate hypothesis for each little subgroup of women.

And that is the model for the only sustainable type of evolutionary hypothesis that could be floated today that would be consistent with the evidence we have, because of that flat distribution of female orgasmic capacity. It means that what’s called a multistrategy set of adaptive hypotheses is necessary. We’ve got to have one situation that’s going to produce the high-orgasmic always-have-an-orgasm strategy, and another one where it’s the only-have-an-orgasm-once-in-awhile strategy that’s going to be adaptive.

And then the tricky bit comes in that there’s going to have to be fairly high resemblance between the offspring and the parent, or fairly high heritability, or else you’re not going to be able to tell an adaptive story about it. And then you’re going to have to slice up the distribution into these different components in order to tell an adaptive story about each one. But you see, because of the distribution being the way it is, that’s the only type of adaptive story that could possibly work. Because other adaptive stories have peaks, sharp peaks where you have an adaptive account and it says, “Look, the best way to be is to have a long snout, and everybody has a long snout.” Now clearly that’s not the case for orgasm, so that kind of account isn’t going to work. And the only account that’s going to be even floatable now is this multistrategy account, and so they’ve got to come up with something like that.

Going back to Dawood, I think that she’s got some of the best samples right now, and her group is pursuing this sort of multistrategy story along the lines of Baker and Bellis, but hopefully with more care, and she might be able to pursue the more interesting and more promising adaptive accounts, and that’s what I’m hoping her group is going to be doing. The oxytocin research, as I indicated in my book, is by far the most promising avenue for something having to do with the sperm upsuck; that might well have to do with sperm competition. This is the most promising avenue and that needs to be pursued, and her group is looking at that. So I’m really hoping that they develop a well-qualified set of classes so that they can then develop individual hypotheses about these subgroups and substrategies, and then float a multistrategy hypothesis that might be testable, rather than just what has happened before. Because one of the bad things about this state of affairs for the past twelve years is that because people had been saying “It’s a fact,” there was a certain laziness about testing.

TM: We’ve already answered that question, so…

EL: Yes, yes, and in fact that question hadn’t been answered, the tests were not adequate, and so I’m really hoping that the future work, especially by Dawood’s group, which I’m quite optimistic about, will fill out the most carefully articulated and theoretically plausible adaptive hypotheses that could then be tested, because I think that’s the way to go.

TM: In the book you talked about how we can’t rely on folk wisdom about orgasm the way we can on other things, because individually we know so little. Some assumptions that are “common knowledge” are wrong—e.g., increased fertility is obviously better—so I start to wonder what else we think we know that’s wrong.

EL: It didn’t strike me when I first started working on orgasm as an adaptation that the assumption that more orgasms leading to more babies was problematic until a number of years later. I don’t recall the exact circumstances but it’s quite clear that you can’t assume that more pregnancies is better. Sarah Hrdy made the case most eloquently in her book Motherhood that I cite in my book, but it’s a general principle in biology that the higher the investment in the offspring, the fewer pregnancies are going to be invested in by the mother. And the investigation of optimal birth spacing that had been done in the ’70s for human hunter-gatherer groups was done because of precisely this issue, the recognition that more babies is not better and does not mean higher reproductive success for the human species. So that’s been recognized for forever. And yet you had, for some reason, in the literature just this old assumption, apparently, that more orgasms and more fertilizations were better, whereas obviously that’s not true. I go through a series of different questions that need to be answered about connecting up uterine upsuck and fertility, and fertility with high quality males, and high-quality males with birth spacing, and birth timing, and so on and so forth.

TM: Why do people (some feminists, for example) think it’s not important if it’s not an adaptation?

EL: I really don’t know why people think that something has to be an adaptation in order for it to be important. The depth of naiveté of that is sort of hard to fathom.

TM: People sometimes take evolutionary explanations of behavior as normative, and they don’t want to hear, for example, about possible adaptive features of sexual infidelity, because they think that means that’s how we have to be. But answering the question of why females have orgasms seems to me to involve description more than prescription.

EL: I don’t know. Just in the last six weeks, I’ve done two interviews with women’s magazines, one from Glamour and one from Self, and both of them were cashing out consequences for women’s sexual behavior from the byproduct view. Both of them were following the dotted line from what I described in the book to what they were recommending to their readers in terms of sexual practices. In particular, one of them was recommending the practice of self-stimulation during intercourse in order to achieve orgasm, because of the well-documented lack of orgasm during unassisted intercourse, as I document in the book. And the second was following the dotted line from the byproduct view to the recommendation that women not follow the sexual script of first-base, second-base, home-run, sex, that they urge their boyfriends to pursue a “more roundabout method” in the bedroom, so that the woman too can achieve orgasm. And so in this case, you have Glamour and Self, following on the heels of a recent Cosmo article that was based on the book, also all about self-stimulation during intercourse. And a piece in Redbook…they’re all drawing conclusions based on what as you know is simply the delivery of a summation of 75 years of sex research. So yes, they are finding applications.

TM: I wonder if it’s possible to talk about anything involving human nature, sexuality, behavior that people wouldn’t take a prescription from.

EL: What I found in discussing these issues with the young women writers of these women’s magazines is that there’s a dearth of discussion of some of the basics of physiology out there. And I guess more importantly from a normative point of view, what appeals to them about the byproduct view is that this, to them, does seem to give them some kind of normative basis. Because they do seek some account that goes like this: Evolution made you like this; it’s a developmental thing, and you came out like this because biology made you like this. Therefore when your boyfriend head-trips you because you don’t have orgasms during intercourse, you just tell him, “I didn’t evolve in order to have orgasms from intercourse, you schmuck.” And this was never so clear to me as during a recent discussion with one of these writers, that this was a line that they were interested in taking. But yes, this is something that’s important to them to convey to their readers. And this is how it’s carrying out into the broader culture.