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The Case of the Female Orgasm: Bias in the Science of Evolution Hardcover – Apr 22 2005

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Product Details

  • Hardcover: 320 pages
  • Publisher: Harvard University Press; 1 edition (April 22 2005)
  • Language: English
  • ISBN-10: 0674017064
  • ISBN-13: 978-0674017061
  • Product Dimensions: 14 x 21 cm
  • Shipping Weight: 476 g
  • Average Customer Review: 3.0 out of 5 stars 1 customer review
  • Amazon Bestsellers Rank: #1,380,314 in Books (See Top 100 in Books)
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Product Description

From Publishers Weekly

Biologists agree that the male orgasm has a straightforward evolutionary function: it makes males want to have sex more often, which in turn makes them more likely to have offspring. But how to account for female orgasm, when nearly three-quarters of women don't always reach orgasm during sexual intercourse? Were they driven by the same evolutionary pressures, females would have adapted to be as consistently orgasmic as males. Through the vast majority of this book, Lloyd, an Indiana University biologist and philosopher of science, trashes evolutionary arguments, which range from pair-bonding (orgasms make females more likely to form stable partnerships) to sperm competition (orgasms expel previously deposited sperm from other sexual partners). Lloyd draws on the earlier work of Donald Symons to account for female orgasm as "a byproduct of embryological development," like male nipples. Lloyd argues that "the history of evolutionary explanations for female orgasm is a history of missteps, misuse of evidence, and missed references." Though built on a comprehensive survey of female sex research, the book is more a salvo in a scientific debate than an introduction to the field, and lay readers may well find it drier and at times more opaque than expected. (May)
Copyright © Reed Business Information, a division of Reed Elsevier Inc. All rights reserved.


Lloyd's book isn't just a "must-read," it's a must-own, must-cite, and must-assign-to-one's-students. William James once defined philosophy as "an unusually stubborn effort to think clearly." This is the most stubborn effort I've ever seen to think clearly about female orgasm.
--Rachel Maines, author of The Technology of Orgasm

The Case of the Female Orgasm is a review and analysis of the possible adaptive significance of the female orgasm. For decades, evolutionary biologists have questioned why this physiological and emotional response should occur in women; men need orgasm to propel sperm out of the penis and into a female reproductive tract to improve their reproductive success, but women need not orgasm to conceive. Thus female orgasm is a biological puzzle. Some evolutionary biologists have insisted that the response is adaptive while others consider female orgasm an ex-adaptation, a trait that appears only because it happens to appear in the other sex. Both camps have written extensively about their views, both in the popular literature and in academic writing, but to my knowledge, no book has focused solely on female orgasm.
--Meredith F. Small, author of Kids: How Biology and Culture Shape the Way We Raise Our Children

This will make great bedside reading. What, after all, is sexier than a well-constructed argument? Lloyd provides a measured and scholarly evaluation of adaptive and non-adaptive explanations for human female orgasm, a trait that has been the subject of some controversy, and she does it without jargon or acrimony. It is a model of how to fairly and critically look at adaptation.
--Marlene Zuk, Professor of Biology, University of California at Riverside

Lloyd summarizes dozens of evolutionary accounts of the female orgasm--and knocks them all down. Like [Stephen Jay] Gould, she thinks the female orgasm is purposeless; which is not to say pleasureless. And she extends the charge of bias, charging that too many scientists take the male-centered view that the female orgasm is closely linked to heterosexual intercourse and reproduction.
--Christopher Shea (Boston Globe 2005-04-24)

It's been 52 years since scientists first considered the female orgasm a legitimate object of scrutiny (thank you, Dr. Kinsey). But they still can't settle on its raison d'etre...Lloyd knocks down all but one of the 21 existing explanations. Along the way, she makes a critical distinction between sexual arousal, which she says is critical in evolutionary terms because it makes women want to have sex (and thus results in pregnancy), and female orgasm, which she argues is merely a bonus...Lloyd settles on the unpopular but, she insists, most scientifically solid theory available...From an evolutionary perspective, female orgasm is superfluous...Lloyd hasn't written off the possibility that an 'obscure' and 'exquisitely designed' Darwinian function has yet to be discovered. But for now, she makes a convincing case that from an evolutionary perspective, female orgasm is just the icing, not the cake.
--Sue Ferguson (Maclean's 2005-04-29)

[Lloyd's] study of evolution and orgasm offers the most thorough and serious treatment of the subject to date--and strongly rejects the claim that orgasm in women serves an evolutionary purpose. Lloyd has scrutinized 21 evolutionary accounts of female orgasm and makes a convincing case for the single account that treats orgasm as a happy accident, a byproduct of the role that male orgasm plays in reproduction and the sharing of early embryonic tissue by the male and female genitalia. The other 20 theories she dismisses as illogical or incompatible with data on women's sexuality. This time the press has it right. Lloyd's analysis is worth all the attention.
--Amanda Schaffer (Slate.com 2005-05-26)

Okay, you have to be a science nerd to read this, a Stephen Gould fan, but what's here is [fascinating]. Really, the most radical book about how female orgasm has been so sensationally misunderstood and manipulated. Lloyd doesn't draw political conclusions--but you sure will.
--Susie Bright (susiebright.blogs.com)

Lloyd's book is penetrating and tantalizing, even intensely satisfying...Her findings about the scientific process really are something to scream about.
--Alison Motluk (Toronto Globe and Mail 2005-05-28)

The conclusion, Lloyd argues, must surely be that the female orgasm has no biological function. Rather, it's on a par with the male nipple--an accident of shared developmental pathways in the early embryo. Because women need nipples to suckle their babies, men end up with rudimentary versions too. They may not give milk, but like the female's they have erotic sensibilities. As for genitalia, because men need ejaculatory penises, women end up with clitorises capable of similar sexual pleasures. Lloyd reckons that biases in evolutionary thinking have blinkered generations of mostly male biologists. It is time to give up the adaptationist's fallacy and face facts. The late Stephen Jay Gould, who encouraged Lloyd's long-standing investigation, must be cheering from above.
--Gail Vines (New Scientist 2005-05-14)

The Case of the Female Orgasm is of particular interest because it offers a fairly accessible account of competing scientific theories, how they are presented (and accepted), and what evidence they are based on. The data on female orgasm is shockingly flimsy, and Lloyd nicely shows how even carefully conceived experiments (such as for testing the upsuck theories) present a host of problems. Far more troubling, however, is what the scientists do with that data, often using it as they see fit--or simply incorrectly using it...This is an important book, and highly recommended to all scientific practitioners (who might be reminded of the bias that can so easily creep into their work) as well as those who interested in everything from scientific methodology to the role of science in society. (The Complete Review)

Underlying biases exist throughout science, but surely nowhere in as extreme a form as in research into female sexuality...Elisabeth Lloyd neatly dissects the history of these biases and their results in The Case of the Female Orgasm.
--Sarah Venis (The Lancet 2005-09-03)

She has an interesting and important set of theses. On top of that, her argument has a straightforward, logical structure…I recommend Lloyd's book to all philosophers of biology and students of human evolution.
--Dr. Rob Loftis (Metapsychology)

Lloyd asks whether female orgasm is really related to reproductive success. The search for an answer reads like a mystery story and involves the critical examination of 18 theories developed on the premise that the human female orgasm is an evolutionary adaptation. The author invalidates each of these theories by an examination of their assumptions and, in many cases, the frailty of their supporting data...With its 355 references, this book is a study of the power of a careful analysis of data to show the weaknesses of certain theories.
--W. P. Anderson (Choice 2005-09-01)

In this scientific review of the literature on women's ability to orgasm, Lloyd lined up thirty years' worth of studies designed to prove that women's orgasms evolved solely to make us better at reproducing and proceeds to demolish them all due to their crappy data, bogus assumptions, or fatal bias. She instead makes a case for men and women having separate, autonomous sexuality. Human orgasm evolved because men need it to reproduce, and women got it as a developmental byproduct. How women use that gift is ours to determine. Feminism and scientific theory can be uninspiring bedfellows, but Lloyd proves here that tenacity and hard work can bring them to a readable climax.
--Beth Brown (On Our Backs 2005-09-01)

Elisabeth Lloyd provides a comprehensive and critical review of evolutionary explanations of the female orgasm. Through her extensive analysis of 37 years of research on the topic, she argues against the prominent theory that the female orgasm is an adaptation that has evolved to improve reproductive success...Lloyd provides a careful and impartial analysis of the validity of the findings from cross-cultural, animal, and human sexuality studies. Contrary to the adaptation perspective, Lloyd supports the theory, originally proposed in the late 1970s, that the female clitoris and orgasm are by-products of the embryological development of the penis and orgasm in males...The work touches on many of the biases that negatively affect scientific rigor and consequently (mis)shape our understanding of women's sexual functioning.
--Jayne E. Stake and Amy K. Silberbogen (PsycCRITIQUES)

Lloyd is a philosopher of science interested in evolutionary biology, and she provides a measured scholarly evaluation of both the adaptive and nonadaptive explanations for human female orgasm...Her meticulously researched book examines 21 explanations for the evolution of female orgasm...The book becomes about much more than an aspect of human sexuality. It is an examination of how evolutionary biologists think, and how their system of gathering and evaluating knowledge can falter. Her reasoned approach is refreshingly free of jargon in a field that sometimes seems abstruse for its own sake; even if one does not agree with Lloyd's conclusion, the book provides a blueprint of how to critically evaluate scientific arguments.
--Marlene Zuk (Perspectives in Biology and Medicine)

In this engaging and carefully argued account, philosopher Elisabeth Lloyd guides her readers through one of the most fascinating controversies in evolutionary theory.
--Mark E. Borrello (Quarterly Review of Biology)

In this closely argued study, [Lloyd] shows how the leading evolutionary accounts of the human female orgasm are based on two flawed assumptions: that the female orgasm evolved because it contributed to reproductive success ('adaptationism'), and that female sexuality is like male sexuality ('androcentrism'). This is an important book that casts light on the biases that can prejudice science.
--PDS (The Guardian 2006-12-09)

Upon your shelf...there probably isn't a book on evolution and the female orgasm. That's because it hasn't been written until now...Evolutionarily speaking, the female orgasm is 'for fun,' says Lloyd, and her theory...adds to its more intellectual joie de vivre.
--Michelle Humphrey (Bust 2007-02-01)

Lloyd, a biologist, philosopher and science historian, uses the human female orgasm (an evolutionary development unique among primates), and science's wholly inadequate explanations for it, to focus on the ways science can be led astray by the biases of those practicing it.
--H. J. Kirchhoff (Globe and Mail 2006-12-30)

Methodical and lucid, Elisabeth Lloyd's The Case of the Female Orgasm is an exemplar of accessible science writing. Those interested in evolutionary biology, philosophy of science, and feminism will find the book an interesting, if perhaps occasionally frustrating, read...Lloyd offers a rigorous case study showing how political and methodological biases have distorted the practice and results of evolutionary investigations of female orgasm....Although parts of the book are somewhat technical, Lloyd carefully explains most of the crucial concepts and educated readers will find it generally accessible.
--Meynell Letitia (Hypatia 2007-07-01)

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Format: Paperback
I guess I expected more in terms of what we know and it turns out that even today we still know very little about the subject.
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Amazon.com: HASH(0x9d400e10) out of 5 stars 17 reviews
49 of 51 people found the following review helpful
HASH(0x9dad499c) out of 5 stars More About Science than Orgasms June 24 2005
By Rob Hardy - Published on Amazon.com
Format: Hardcover
Science is the way we have of finding out how the components of the universe work. Science works very well, in general; our increase in understanding of everything from galaxies to quarks is really quite admirable. Nothing humans do is perfect, and the world's scientific effort, for all its successes, has a history that also includes some missteps, prejudices, and erroneous conclusions. It is somehow not surprising that in investigating sexuality, which is still for some people a controversial endeavor, there have been consequential mistakes. This is probably because the subject is both vitally important to us all and also private and covert. Compound this with particular investigation of female sexuality, and all sorts of prejudices might be expected to occur. In _The Case of the Female Orgasm: Bias in the Science of Evolution_ (Harvard University Press), Elisabeth A. Lloyd has examined how scientists have tried to understand how female orgasms evolved. "Female orgasm is a source of fascination for groups ranging from sex researchers to the lay public, and evolutionists are no exception," she writes. Unfortunately, Lloyd shows that the evolutionists' fascination has borne erroneous explanations. This is a tiny area of evolutionary science, but it has been explored and written about by many, often in opposing camps, and Lloyd has given a detailed and serious refutation of all explanations but one, the one she championed in a paper twenty years ago. Others might find this a tempest in a teapot, but Lloyd's serious tone and exhaustive analysis of the flaws in other researchers' ideas, and the causes of those flaws, make this a fascinating book of scientific advocacy.

Females don't have to have orgasms to bring forth children, so why do they have orgasms? Lloyd has tried to find every explanation that evolutionists have proposed, and has come up with twenty-one of them. Almost all have found the female orgasm to be an adaptation, meaning that it is a trait that has evolved to promote fitness in some way, but over and over again, she shows how the proposals of the "adaptationists" are flawed. Lloyd is adamant: "There is no plausible evidence that links orgasm to reproductive success." Her arguments against this proposal are many, among them that the number of women who always orgasm with coitus is a minority, about 20%; one would think that if orgasms were an important adaptation that led to successful reproduction, they would be far more common and far easier to get by coitus, rather than, say, masturbation. A particularly attractive explanation, one which has even been spotted on the Discovery Channel, is charmingly called "The Upsuck Hypothesis". It says that during orgasm, the uterus has a drop in pressure, becoming a sort of vacuum cleaner to suck up any sperm deposited by the male. This would be a reproductive advantage, but even Masters and Johnson found no evidence that upsuck happens.

Lloyd finds plausible one explanation of female orgasm, the one that does not insist that it is an adaptation. Donald Symons in 1979 proposed the "byproduct account". Female orgasm is a potential based on anatomy, a potential activated only in some females of some few species. The anatomical foundation is similar to the nipple in the male. Operating female nipples are strongly selected for, since they supply nutrition, and are present in the embryo, even before the embryo differentiates sexually. Thus, inoperative male nipples are a byproduct of selection operating on the female. In the same fashion, orgasm and ejaculation are strongly selected for in the male because of sperm delivery. The hardware involved in such actions is there in the embryo that might turn male or might turn female, and females get the erectile, highly-enervated clitoris because the analogous penis in the male is so important. (This also offers an explanation for the puzzling fact that the key point of sexual stimulation for females is not in the vagina which receives the sexual organ of the male, but on the connected tissue of the clitoris.) There are feminist objections to this idea, because a female orgasm is derivative from the male one, but this is putting ideology before science: "Its historical genesis does not dictate our cultural attitudes toward female orgasm." Lloyd has looked widely at this explanation and all the others, and has taken pains to list evidence and arguments pro and con. She has also given a broader critique to show how androcentrism or illusory concepts of human uniqueness have caused the mistakes in reasoning of the adaptationists. This is a far from titillating volume; surely there are not even fetishists who could get off on so many pages of deconstruction of one arcane theory after another. As an account of competing scientific ideas and how preconceptions form them, however, it is a uniquely valuable account.
19 of 22 people found the following review helpful
HASH(0x9dad45e8) out of 5 stars A solution to the conundrum of female orgasm? Aug. 10 2005
By R. Altman - Published on Amazon.com
Format: Hardcover
It's not been uncommon to wonder why women have an orgasm - a reflex devoted to pleasure with no apparent further purpose, including procreational. Naturally, lay people and scientists alike have wondered whether it has some hidden, evolutionary purpose. And so, apparently, there have been 21 theories on the subject since the mid 20th century, all speculating on the purpose of the female orgasm. And according to professor Lloyd, with one honourable exception, they have all been just that - speculation - for in this book Lloyd conducts a meticulous piece by piece deconstruction, and ultimately demolition, of these attempts to crack the conundrum.

Much of the 20-odd conclusions are based, among other things, on surveys, and Lloyd's first salvo comprehensively points to the holes in these surveys. They fail even to achieve a proper definition of the female orgasm, and then go on, on the say-so of unreliable witnesses and dodgy surveys, to build a picture of the experience of womankind in this area. Anatomically speaking they by and large even neglect the crucial matter of the varying proximity of clitoris to vagina. In my observation, in terms of the general survey of the phenomenon, they also seem to neglect the importance in pre-orgasmic arousal of the panoply of mental issues involved. At some point in the evolving literature, investigators did come to differentiate between 'assisted and unassisted orgasm with intercourse', but I suspect they don't really understand what they're talking about here either, given the great variability of practices that the term 'assisted' might cover here.

I was pleased to see that Lloyd, when considering the supposedly differing post-orgasmic refractory periods between men and women, unusually, does at least give a one line acknowledgement of the practice of male 'retention' and what may be learnt from it.

Cutting to the chase, the one theory that Lloyd is sympathetic to, is the 'byproduct' theory, developed by Donald Symons in the 70's. Evolutionary biologists distinguish between adaptations and traits, more broadly speaking. An adaptation is a development which contributes to reproductive success (hominids standing up on their hind legs), while a trait, although genetic and inherited, may or may not (like our differing eye colours.) Writers in this field have displayed an inclination, tantamount to an assumption, that the female orgasm is an adaptation. Unpalatable as it may be, especially to a certain section of feminists, all the evidence for female orgasm being an adaptation proves to be paper thin. The trait/byproduct theory, on the other hand, runs thus. The human embryo lies sexually undifferentiated for the first 8 weeks of life; it has a genital tubercule, and it also has nipples. Then the embryo becomes either male or female. The female develops nipples capable of delivering milk, while the male nipples, with no need so to do, remain, a spinoff of the primordial nipples, with no reproductive (or essentially other) function. Similarly, while the genital tubercule in males goes on to become the penis as we know it, the female equivalent emerges as the (already sexually sensitised) clitoris.

It is argued that female orgasm is an adaptation only if in ancestral populations orgasmic females enjoyed greater average reproductive success than nonorgasmic females. Naturally, it is rather difficult to discover very much about the sexual experience of our female ancestors. Given that on any public scale, the clitoris and female orgasm have only even become known to a small section of humanity for a small section of history, I would suggest that they may have lain dormant, undiscovered, and totally useless and unused for the majority of humankind, for the majority of our time on earth so far.

One of the threads in the book looks at research into female orgasm in the animal world. There are greater and lesser supporters for the notion that females in the wild have orgasms. I would suggest that the relevant issue is not whether or not they actually have orgasm, but the degrees to which they are potentially capable of orgasm - and this is a stronger possibility. Some monkeys and apes are capable of learning to take advantage of the orgasmic possibility for their own pleasure - possibly, just like women have done!

The book is subtitled 'Bias in the science of evolution.' The 'case' in the main title is both specific and general. Specifically, about investigating the female orgasm, and generally, about the pitfalls of scientists' own prejudices creeping into their research. Towards the end Lloyd summarises this thread of the book with a list of eight assumptions she identifies as having been made by the scientists under scrutiny here. Having said all that, she does make the point that although unpersuaded so far, she remains open to the case for the adaptive orgasm, should further evidence be forthcoming.

There was just one book, (The Sex Contract, by anthropologist Helen Fisher) which, in her own admission (personal communication), the author confessed she had overlooked in her research, and has resolved to review soon. I suspect that this one too will fall under her analysis. I find her argument persuasive. (So did the late Stephen Jay Gould.) I leave the final judgement to her scientific peers. As a lay person (!), I welcome any further demystification, demythologising and de-media-fying of this glorious territory. The truth will set us free - in the boudoir, as elsewhere.
5 of 6 people found the following review helpful
HASH(0x9d1e5e88) out of 5 stars A wonderful book Jan. 3 2009
By Amanda Dixson - Published on Amazon.com
Format: Hardcover
Professor Lloyd has the advantage of being a historian and philosopher of science, as well as being a biologist. Thus, this book succeeds on several levels. Firstly it provides a well-organised review of the numerous theories advanced to account for the evolution of female orgasm. The most credible theory is due to Symons, who posited that orgasm in women represents a homologue of the male orgasmic response. As such it is an epiphenomenon....much like the nipples, or the vestigial uterus masculinus are functionless homologues in males.

The bizarre theories of evolutionary psychologists, such as Baker and Bellis are reviewed fairly, critically and at some length in this book. Hopefully this will help to put to rest ideas that are still cited in the literature, concerning the existence of "sperm retention" orgasms in humans, and other absurdities. The second value of the book is thus its detailed analysis of the flawed methods and poor reasoning applied in various studies of female orgasm. The third perspective it provides is historical, tracing how such theories developed and how they came to be widely cited by authors who were at several removes from the experimental reports and (presumably) failed to check original sources. Professor Lloyd clearly checked her sources, and has written a wonderful book.For there was bias in this field, and it needed exposure.
21 of 29 people found the following review helpful
HASH(0x9f6c14b0) out of 5 stars Comprehensive and astute April 24 2005
By William Mealiffe - Published on Amazon.com
Format: Hardcover
Elisabeth's A. Lloyd's book is a comprehensive survey of the theories and conjectures that try to explain the evolutional basis for the female orgasm. It is extremely well argued, and convincely rips into the biases of those who have proposed various adaptational (versus exaptational) accounts. Lloyd shows how theorists have misconstrued and ignored research into human female orgasm and primate female orgasm when drawing their conclusions, and makes a convincing case that many theorists started out with an a-priori notion that human female orgasm has to be adaptive. This book is great documentation in one area on how biased scientists can be, how undisciplined their reasoning can be, and how much this invalidates their conclusions. And the upshot is, if scientists are biased on this subject, how many more areas of research are they biased about?
9 of 13 people found the following review helpful
HASH(0x9d7163cc) out of 5 stars A major accomplishment and enormous contribution to the field of human sexuality. Nov. 16 2005
By Ian Kerner - Published on Amazon.com
Format: Hardcover
In her compelling book The Case of The Female Orgasm: Bias in the Science of Evolution, Elisabeth Lloyd examines whether or not the female orgasm is an evolutionary adaptation resulting from the process of natural selection, or rather an evolutional by-product of natural selection in the male and, hence, a function of the embryologic relationship between the penis and the clitoris. In short, does the female orgasm have its own evolutionary raison d'etre, or is it a happy accident? To elaborate: for the female orgasm to be a true adaptation, it would need to contribute directly to reproductive success (like the male orgasm).

Ms. Lloyd examines twenty-one theories that seek to promote the female orgasm as an adaptation -- from the role of orgasm in helping to facilitate the pair-bonding process to upsucking and sperm-competition -- and finds each and every one of them lacking. One of her main arguments is that it's been well documented that the vast majority of women do not experience orgasm as a result of intercourse alone, or do so inconsistently, and that clitoral stimulation is not a consistent feature of intercourse. She refers to this as the orgasm/intercourse discrepancy (and it's one that far too many women are all too familiar with).

Thus, if orgasm fails to occur via intercourse in a significant percentage of the female population, or if it only occurs haphazardly, as every major sexology study/survey on the subject indicates, then it stands to reason that that female orgasm does not play a pivotal role in reproductive success. Since women can conceive without experiencing orgasm, it cannot be considered an adaptation.

But does this theory goes against the grain of survival of the fittest? If mutual pleasuring and long-term sexual fulfillment are understood as an aspect of the natural selection process, then it can be argued that the female orgasm is an inherent screening device, and that couples who are more attuned to each other and more sexually fit (mutually orgasmic) are more likely to stay together and have more babies than their sexually unfulfilled counterparts. Yes, conception can occur without female orgasm, but natural selection favors the survival of the sexually fittest.

Another explanation for the origin of the female orgasm is based on what is known as the "by-product" theory, which holds that orgasm is a trait that is heavily selected in males (reproduction wouldn't happen without it). As men and women are embryologically undifferentiated during the first eight weeks of gestation, the clitoris is homologous to the penis, and thereby retains the male capacity for orgasm. Penises grow out, clitorises grow in, but they share the same organic structure and tissue.

Says Lloyd, "It is crucial to note that the penis and the clitoris are the "same" organ in men and women ... [T]he nervous and erectile tissues involved in orgasm in both sexes arose from a common embryological source... These tissues are what the sexual organs are built from, especially the penis in males and the clitoris in females."

On the subject of genital similarity and orgasmic potential, Lloyd continues, "A concert of interactions is involved in producing orgasm in males - these interactions are present in both mature and immature males - and does seem to be paralleled in females."

But from an evolutionary vantage, we recognize that the female and male orgasm are fundamentally different, in that the male orgasm is essential to reproduction whereas the female orgasm is not. The same principle also explains the origin of male nipples. Accordingly, the biological necessity of nursing our young makes the nipple so highly selected that males develop embryologically immature structures as an evolutionary by-product.

Similar to the clitoris, the male nipple contains highly sensitive tissue that contributes to male sexual arousal and pleasure. So perhaps this facility for non-procreative arousal does have a purpose after all, in that it contributes to greater sexual pleasure and, hence, higher rates of conception. Couples that best stimulate each other sexually in a variety of ways are less likely to grow bored, more likely to stay together and, therefore, naturally selected to produce more young.

So why does this rarefied debate of adaptation versus by-product matter to the average person who just wants to enjoy orgasms? Because we tend to believe what is "natural" or biologically determined/selected is what is correct. Our sexual scripts derive from a paradigm of procreative necessity.

The dominant ideology of sex valorizes coital penetration above all else. But I heartily maintain that our ability to sustain sexual interest and pleasure each other outside of procreative purpose in a variety of ways naturally selects the endurance of healthy "pair-bonds." It inscribes a Darwinian ethos that favors the survival and reproduction of the sexually fittest.

As a sex therapist I receive emails daily from women who are unable to achieve orgasm via intercourse and wonder, "what can I do to change this? What's wrong with me?" Well if we stop thinking of female and male orgasms as something that "naturally" should result from intercourse, we can liberate both men and women from the oppressive intercourse-discourse (a belief that there's a right way to have orgasms, and simultaneous ones at that).

Understanding and respecting the vital importance of mutual sexual pleasure ensures the health and success of our long-term relationships. By finding new and varied ways to pleasure each other, we can abate the cultural compulsion to get bored, break up, and search for new partners. The role of the female orgasm, which I celebrated in She Comes First, is an essential starting point for liberating ourselves from the hegemony of sexual normalcy based on biological determinism.

Much thanks to Dr. Lloyd for providing such fine intellectual fodder.