Elizabeth Lloyd’s new
book has attracted a lot of attention for a technical work of academic philosophy,
including profiles in the New
York Times and Slate, and an appearance on The View
(right between an interview with television doctor Noah Wyle about the health
insurance crisis in America and a tribute to Merv Griffin). Lloyd was even the
subject of a joke on Saturday Night
Live’s "Weekend Update," certainly a first for the philosophic
community. 

Lloyd’s book is
obviously receiving attention because her topic is, quite literally, sexy. But
perhaps more importantly for the popular media, her theses are very easy to
state in layman’s terms. Lloyd believes that the female orgasm is a
evolutionary byproduct of the male orgasm, the same way that male nipples are a
byproduct of the evolution of female nipples. Furthermore, she believes that
biases in the research community have prevented scientists from seeing this
obvious truth, including a bias toward adaptive explanations and a nasty
tendency to assume female sexuality is like male sexuality. Clearly, she has an
interesting and important set of theses. On top of that, her argument has a
straightforward, logical structure. She canvasses the 20 adaptive accounts that
have been proposed so far and finds obvious gaps in reasoning, while the one
nonadaptive account has a lot of prima facie evidence for it. It is nice to see
that you can get on television with a clear and important argument.

Once you get into the
details of her refutations of the individual adaptive accounts things become
more complicated, but certain consistent themes emerge. Twelve of the accounts
she surveys are pair-bond accounts that is, they assert that the female orgasm
evolved to reinforce a monogamous bond between a man and a woman. All of these
accounts descend, in one way or another, from Desmond Morris’s infamous The Naked Ape, which painted a popular,
seductive picture of human evolution that was little more than a projection of
his contemporary Father Knows Best
suburban culture on our hominid ancestors. All of the pair-bond accounts falter
on a basic fact of female sexuality. Women do not orgasm reliably with vaginal
intercourse. After a painstaking review of the sexology literature since 1921,
Lloyd concludes that about 10% of women never have orgasm with vaginal
intercourse and about 25% always have orgasm with intercourse. The middle 65%
of women are contingent orgasmers, climaxing when the circumstances are right.
In contrast, 95% of women who masturbate can achieve orgasm that way, and they
do so in the same amount of time it takes men to orgasm, about four minutes.
None of the pair-bond accounts can explain this distribution. For Morris, the
orgasm simply reinforced the pair bond. But if that were the case, we would
expect selective pressure towards consistent orgasm. So 75% of the variation is
left unexplained. A more sophisticated pair-bond account, due to John Alcock,
suggests that female orgasm serves a function in mate selection: men with the
decency to give their partners orgasm are also likely to be good fathers, so
contingent orgasmers have an advantage over others in their ability to select
good mates. But this account still leaves 35% of the variation–the women who
always or never orgasm–unexplained.

Other adaptive
accounts run into other problems. Many are based on faulty work by Baker and
Bellis which purported to show that orgasm causes an "upsuck" of
sperm into the uterus. At the most basic level, there is no empirical evidence
that women who orgasm have had more reproductive success than women who do not.
In the end, Lloyd argues that the loyalty to adaptive explanations can only
come from an irrational bias toward adaptive explanations and a failure to
understand female sexuality, evidenced primarily in the failure to appreciate
the variation in female ability to orgasm.

The structure of
Lloyd’s argument suggests an easy route for rebuttal: one simply goes looking
for missing adaptationist accounts. The book would be obviously inadequate if
there were compelling accounts out there that were overlooked. This line of
argument turns up some oddities. No account that has actually been developed in
the literature Lloyd is critiquing has been overlooked, so her charge of bias
holds up. However, there are nascent ideas in the literature that Lloyd does
not hit on, some of which may yield fruit in the future. One popular account of
the male orgasm is the "when to stop masturbating theory." It is
obviously adaptive for men to enjoy stimulating their genitals, but without a
clue as to when to stop men could actually damage their sex organs from too
much rubbing. Male orgasm, on this theory, lets us spare our chafed privates
and move on to other things. Why not extend this account to women? The female
version of this theory is missing from Lloyd’s book, but that is no loss
because the female version of the theory is a nonstarter. It only works if you
assume that female orgasm is like male orgasm in that it makes one sleepy and
uninterested in sex. But Masters and Johnson, along with personal experience
and popular wisdom, show that this is not the case. Women, after orgasm, return
to a plateau level of sexual excitement.

More troubling is the
absence of serious discussion of possible models for the evolution of human
sexuality from the bonobo research. Right now we have a fairly clear picture of
bonobo sexuality, both from field studies like the work of Takyoshi Kano and
Hohmann and Fruth and from captivity studies like the work of Franz de Waal.
These studies show that bonobos use sex to mediate a wide range of social
difficulties, including preventing conflicts and aiding reconciliation after
conflicts, regulating tension, solidifying same-sex and different-sex
alliances, and expressing social status. A parallel account of the evolution of
the human female orgasm would be a kind of social bonding account, quite
distinct from the pair-bond accounts offered by Morris and his followers. Such
an account would not stumble on what Lloyd calls the orgasm/intercourse
discrepancy, because stimulation would not be limited to vaginal penetration,
but could include cunnilingus and manual stimulation.

In an email to me, Lloyd
said she was open to such an account, but has her doubts, largely because the
cross-cultural evidence suggests that males typically show little interest in
providing direct clitoral stimulation, or in female pleasure at all, and
because competition between females played more of a role in human evolution
than cooperation, at least according to Sara Blaffer Hrdy. In any case, this account
has never been fully developed, so Lloyd does not need to respond to it. It
does, however, reveal an oddity in Lloyd’s argument. For Lloyd, the so called
"orgasm/intercourse discrepancy" is a crucial piece of evidence
revealing androcentric bias in current research. But she mischaracterized the
discrepancy in a way that also falls victim to androcentrism. (In saying this I
mean no insult to her feminist credentials. Even the best of us have lingering
androcentric biases.) The discrepancy isn’t between orgasm and intercourse but
between clitoral stimulation and vaginal stimulation. Only 25% of women
reliably achieve orgasm with vaginal stimulation, but 95% of women can achieve
it with clitoral stimulation. But this is only a gap between orgasm and
intercourse if you assume that intercourse means vaginal intromission. This
Clintonesque definition of sex is clearly androcentric, indeed, phallocentric.
Moving past it can only improve our understanding of evolution.

This is an excellent
book, and it makes an important point, but it has a number of quirks. My
biggest complaint is that little space was devoted to analyzing the bias behind
this science and to methodological issues in general. The bulk of the book is
spent critiquing the existing models. Only in the last chapter do we get a
discussion of how bias led to these models and what the role of bias should be
in science–in short, the actual philosophy. The structure of the book is also
peculiar. Since the argument has such a clear logical structure, it would make
sense to pattern the book the same way. Instead we get odd digressions. The
accounts being critiqued occur in chapters three, four and seven. In between we
get a discussion of adaptationism and a survey of the account Lloyd likes. I
also had trouble individuating accounts at times. (Does Morris present one
account or two?) Nowhere is there simply a list of the 20 accounts she
critiques, although there is a list that covers 18 of the 20. This book also
had a long gestation period, which makes parts of it seem weirdly dated. Lloyd
started working on this material 20 years ago and published a major paper on it
in 1993. A lot of space is devoted to refighting a battle led by Stephen Jay
Gould in the pages of Natural History
in 1987. This time capsule quality is in part responsible, I think, for the
neglect of recent bonobo research.

I recommend Lloyd’s
book to all philosophers of biology and students of human evolution. I plan to
use it in an upper level undergraduate course in the philosophy of biology next
spring. I also recommend much of the Internet discussion that has occurred on
this topic, and the related topic of a
study by Dunn et al showing that ability to orgasm is about 45% heritable. Lloyd
discusses the study on the weblog Philosophy
of Biology. Anthropologist John Hawks also has some interesting reflections
on John Hawks Anthropology Weblog (on heritability
and Lloyd).

© 2005 Robert Loftis

Rob Loftis, Ph.D., Department of
Philosophy, St. Lawrence University

Categories: Philosophical, Genetics, Sexuality