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On Women's Sexuality: An Evolutionary Perspective©
by
Lara Eschler


" ...All I have to say about femininity is certainly incomplete and fragmentary and does not always sound friendly...If you want to know more about femininity, enquire of your own experiences of life, or turn to the poets, or wait until science can give you deeper and more coherent information"
(Freud, 1931).


The evolutionary function of sex is reproduction.  Humans seem to enjoy sex so much that they do not hesitate to engage in sex even when reproduction is not involved.  Human females conceal their ovulation; they have sex while pregnant and they reach menopause in mid-life and continue to have sex.  These qualities, along with our unique ability to reason and ponder, seem to make us distinctively human (Diamond, 1997).  Perhaps above all, female sexuality seems to be the most complex to elucidate from an evolutionary perspective.   Some theorists seem to have managed to give evolutionary reasons for concealed ovulation; in their opinion, concealed ovulation seems to serve the purpose of keeping the male around.  Since the male is uncertain of when exactly the female is ovulating, he would stay around because he wants to make sure that when an ovum is released his sperm will be able to meet it.  In addition, he would not want to take the chance of his partner being impregnated by somebody else; having to rear someone else's children would obviously be detrimental or would even represent his genetic suicide.  For the above reasons, the male is compelled to stay around and, his paternity almost ensured, might find it advantageous to help with the rearing of his children to increase the chances of their survival.

Theorists have also explained menopause from the evolutionary perspective, maintaining that childbearing at a late age would not be advantageous, especially for the woman who already has children.  Therefore, she ought to concentrate on taking care of her existing children, grandchildren and relatives (Diamond, 1997). (Although her sexual receptivity remains).

Perhaps the characteristic of human female sexuality that I find the most perplexing is the female's physiological construction, specifically, the physiology of the clitoris.  The clitoris anatomically evolved in a very similar way as the penis.   The penis, for example, has two roots know as "crura" which play an essential role in its functioning.  During sexual excitation these crura become engorged with blood and contribute to the erection of the penis.  The clitoris, likewise, has two broad roots which are the same size as in the male.  In a similar fashion, the clitoral crura also becomes engorged with blood at the beginning of a woman's sexual excitation.  The tip of the clitoris, the glans, is especially sensitive, much like the glans or head of the penis (Hite, 1994 p. 45).  Though the spasms produced during orgasm are located in and around the vagina, the primary area of stimulation is the clitoris.  This may have led to the myth that a female is capable of two different types of orgasms, vaginal and clitoral (Ibid., p. 45)  The theory of two distinct types of orgasms, vaginal and clitoral (Hite, 1994).  The theory of two distinct types of orgasms may have led to feelings of inadequacy and confusion for those woman not experiencing both types.

As orgasm occurs primarily through stimulation of the clitoris, and as the primary function of sex should be reproduction, it is perplexing that the clitoris seems to be located in such an inconvenient position.  By inconvenient, I mean that it does not always get direct stimulation through intercourse.  For instance, it would be theoretically possible for a woman to be impregnated with a child through intercourse without having experienced an orgasm.  The opposite, i.e. for a man to impregnate a woman through intercourse without reaching orgasm, would be impossible under normal circumstances.

From the fact that women do not orgasm during intercourse as much as men do, plenty of myths were derived: 1) that women are less orgasmic, 2) That women are less interested in sexual gratification and that they are less likely to seek it, 3) That women are only interested in emotional contentment.  However, if we consider female sexual characteristics, they seem to indicate exactly the opposite, that is to say that female sexual anatomy was made to enjoy sexual sensations depending upon or independent of reproduction.  Studies have indicated that women can reach orgasm as quickly as men through masturbation, and on top of that they are capable of multiple orgasms while men, after having reached orgasm, have a so called "refractory period" in which they are unable to become sexually excited and therefore to reach another sequential orgasm (Hite, 1994).  While a male's ejaculation is always fertile (sometimes sperms are more powerful than others, but they are never completely infertile under normal circumstances), women are able to reach orgasm outside of the ovulation period, while menstruating, during pregnancy, and after menopause.

The orgasmic powers that women have, and their controls over their own orgasms might have scared men off in the past.  This might have led men to try and repress women's sexuality, or at least to control it the best they could in order to make women believe that only males were entitled to enjoy recreational sex (although women seem to be more designed for it).  Perhaps they might have thought that females could become sex fanatics, and this might have scared them off because of the fear of being uncertain over their own paternity.  As we know, since the beginnings of mankind, this has always been a big concern for men: Before the recent availability of DNA testing, how could a man be certain of his own paternity?

By ensuring that woman had little interest in sex, or at least that they conceived of sex only when emotionally involved, men might have believed that their paternity was ensured. In the most extreme cases, men went so far as to practice atrocious rituals such as clirodectomy (the barbaric removal of the clitoris) and infribulation (the sewing together of the labia until the next conception) to ensure their paternity (Buss, 1994). In essence, men ended up negatively impacting female sexuality, in that they were able confuse women about their orgasmic capacities and, at times, even to convince them that they did not need orgasms in order to be satisfied.  Indeed, until the sexual revolution and to this day, women do not always have a clear notion of their orgasmic capacity. (All of this might have caused some damage to female sexuality but still did not ensure paternity).

But what might the causes be for the natural selection of an organ like the clitoris, which is not critical to conception and unlike any other organ or tissue in the body, exists only to receive and give off sexual pleasure?  I believe that this fact begs for explanation, and I was perplexed not to encounter much on the subject in my readings about the evolution of sex.  I will briefly outline some speculations.

As the clitoris is critical for sexual arousal, it might have evolved as a means to compel women to have sex; to motivate them to reproduce and to avoid their finding sex to be a painful task and wanting to escape from it. (Small, 1993).  According to Hite (1994), some women, when aroused through stimulation of the clitoris report a desire to be penetrated.  This feeling of intense desire, comes during the build-up to orgasm, very near the moment of orgasm itself, and then spills over into the orgasmic contractions.  This is an almost hollow feeling, and is caused because the upper end, the deeper portion of the vagina, is ballooning out, expanding into what has theoretically been pictured as a little lake for the collection and holding of sperm (Hite, 1994).   In this case, however, it might have made more sense to have the clitoris situated directly within the vaginal walls, or in a place where its stimulation through intercourse would be more straight forward and automatic.

Before discussing some speculative explanation for the location and function of the clitoris, I will deviate on the subject for a moment and explore reproductive biology and its subsequent mating strategies, which might be implicated in the natural selection for the clitoris.

The human species evolved finding advantageous to have two sexes involved in reproduction; with men contributing small cells and women big cells.  Theorist believe that having two sexual strategies is critical for the elimination of certain bad genes, that will therefore not be past on to the next generation.  Thus, men, produce millions of sperm, which are replenished at a rate of roughly twelve million per hour, while women produce a fixed and unreplenishable lifetime supply of about 450 ova (Hite, 1994).  This leads to different sexual strategies for males and females.  As men have an infinite resource of sperms available to pass on their genes, one could argue that they should adopt the strategy of impregnating as many women as possible.  By producing a high number of offspring, they should have good chances of at least some offspring surviving and successfully passing on their genes.  Women, on the other hand, have a limited number of eggs and the investment in each pregnancy is enormous.   Each pregnancy also decreases a woman's chances of successively reproducing successfully.  Women will, therefore, be extremely selective in choosing a mate with whom to reporduce.  They will optimally select men who are willing to commit and raise their offspring, but they will also look for the best possible genes (looking for better genes may also involve looking outside of a relationship) (Buss, 1994).  Being so selective, women will actively try to avoid unwanted pregnancies.

The second speculative theory has to do with how orgasms increase the chances of conception and we have seen that the clitoris due to its position makes a woman very much in control of her own orgasms, she might use it as a tool to maximise or minimise her chances of getting pregnant.  Women on average eject about 35 percent of the sperm within thirty minutes of the time of insemination.  If the woman has an orgasm, however, she retains 70 percent of the sperm and ejects only 30 percent.  Lack of an orgasm leads to the ejection of more sperm (Small, 1995).  This evidence is consistent with the theory that women's orgams function to aspirate the sperm from the vagina into the cervical canan and uterus, increasing the chances of conception (Buss, D. 1994).  Moreover, if a woman has no orgasm at all, or has an orgasm before the man ejaculates, she retains less sperm and if she orgasms between epidoses of sexual intercourse with a man, by masturbating, or having oral sex with a man or another woman, she also retains less sperm the next time around (Small, 1995).  Thus, by controlling her orgasms, a woman might be able to maximise the chances of a desirable set of sperm to reach her ovum and minimise the chances of less desirable sperm.  And she is able to control her fertilisation due to the particular position of the clitoris.  It is also interesting to point out that women sometimes fake orgasms, perhaps to give the illusion to a man that his sperms have been aspirated even when this is not the case.

Hite (1994), proposes the theory that since women do not have oestrus, like some animals, it is necessary for the clitoris to be located on the outside of the body rather than closer to the vagina, so that stimulation might happen in the normal course of things.  In other words, since women are not periodically receptive like other mammals, there must be some mechanism provided for arousal that can be activated at will and that will not leave women in a constant state of arousal.  However, she subsequently dismisses this theory as women, again, are just as orgasmic outside of fertile periods.  And this is precisely the case that remains to be elucideated.

It seems that women have evolved as sexual beings, their orgasms motivate them to have intercouse and reproduce but might also have evolved to just give a woman pleasure.  Pleasure in itself might be important for survival, it might even motivate survival. Women tend to physically suffer more in life due to childbirth, menstrual cramps, etc.  Therefore, their orgasmic potential, which is not directly crucial for intercourse, might have evolved to compensate the aches and pains implicated in reproduction, which women have to endure.  Hite (1994), also suggests that orgasms might represent a release mechanism for the body, as are other body reactions, such as laughing, crying, or bodily convulsions.  In which case, the release of orgasms would represent a discharge of all kinds of tensions.

In conclusin, I believe that evolutionsits should further investigate about female sexuality and formulate a plausible explanation for the anatomy of the clitoris.   In the meantime, it should just be accepted that women are just as sexual as men and that their sexuality can be even more independent from reproduction than men's sexuality.

Origin: July, 1999


Buss, D. M. (1994). The Evolution of Desire, BasicBooks, New York.
Diamond, J. (1997). Why is sex fun? BasicBooks, New York.
Hite, S. (1994). Women as Revolutioinary Agents of Change.  The University of Wisconsin Press, Madison, Winsconsin Press
Small, M. F. (1995). What's Love Got to Do With It. Anchor Books, New York.
Small, M. F. (1993). Female Choices. Cornell University Press, Ithaca, New York.


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