Once reliable contraception became available it was assumed that intercourse should instantly become for women exactly what it represented for men: an opportunity to enjoy erotic pleasure, arousal and orgasm. But our emotional and sexual responses have evolved over millions of years. We only evolve capabilities that we need for survival and reproduction. A desire to please men or to provide women with pleasure would not cause an evolutionary change. Responsiveness is inherited from our distant past.

Biological precedents provide crucial evidence for human sexuality. We share our ancestry with all life on earth. But more recently we had ancestors in common with primates and before that mammals. So if a characteristic, such as female orgasm, doesn’t exist in these two groups we need strong evidence to explain how women might have evolved such a characteristic.

Mammals have been around for about 225 million years. Primates appeared about 55 million years ago. There is no evidence to suggest that female mammals orgasm any time. In other mammals, masturbation is primarily associated with males. Some female mammals do masturbate but since they do not ejaculate it is difficult to establish that they ever orgasm.

In mammals the male generally initiates the mating act. Ejaculation is evidence of male orgasm because orgasm triggers ejaculation. Within primates the male initiates genital stimulation both of himself as well as the opposite sex. Some female primates will offer to stimulate a male or allow the male to stimulate them genitally. But if this was responsiveness (a subconscious response), then every female would respond in this way.

Men’s top reproductive priority is to maximise his ejaculations and increase his changes of procreating. This means that men are responsive because male orgasm occurs with male ejaculation. Women’s top reproductive priority is to find a mate who will be dedicated to protecting and supporting her through the long process of bearing and raising a child.

While male orgasm (co-incident with ejaculation) is 100% vital to men’s reproductive capability, female orgasm has zero impact on women’s ability to conceive. Women do not experience an arousal cycle as men do. Female orgasm is infrequent and has probably become less common over time. Female responsiveness is incredibly rare, which is logical given female orgasm has never had a role to play in human reproduction.

The internal reproductive organs develop from completely different anatomy in the foetus. There is no overlap between the male and the female. A man doesn’t have a vagina so there is no biological precedent for assuming that women might be capable of being stimulated to orgasm through the vagina. There is no precedent for female orgasm by any means except for the common anatomy that women share with men.

The only sexual anatomy that men and women share is the sex organ. Every embryo has a structure that eventually forms the sex organ (clitoris or penis). The clitoris is referred to as the homologue of (equivalent organ to) the penis. The clitoris cannot be a reproductive organ because it plays no role in reproduction. The vagina, on the other hand, plays a crucial role. Vaginal intercourse is the key sexual act that leads to reproduction.

Sexual pleasure is promoted universally as if it is enjoyed by women as much as by men. It is very evident in nature that sex is a male pleasure. But we assume that human females are different. Women have learned that when they offer intercourse, men are very generous in return. So women have an incentive to offer intercourse regardless of their own pleasure. If a woman depends on a man’s willingness to fight or to earn so it is difficult for her to complain when he wants the intimacy he needs from eroticism.

Polite society (dominated by the female view) tends to condemn any sexual activity outside lovemaking. Many self-righteous heterosexuals condemn sexual pleasuring (based on explicit genital stimulation). To be acceptable to most women, sex must always be portrayed as a loving act justified by the biological precedent. This is despite the fact that most men want intercourse considerably more frequently than is required for reproduction.

Most of the time men have little interest in women, so when a man notices her, a woman is complimented especially if he is successful. We admire men for their bravery because women and children depend on men for protection. At a biological level, men are inclined to take risk. But the fact is that men often represent the greatest threat in the first place.

If a woman sees an advantage in having a man’s protection, she may be motivated to please him sexually. Women may flirt thereby indicating their amenability to a man they admire. This is a conscious behaviour and not a sign of sexual arousal. A man gives through his role as protector (where a man supports the family) and defender (where a man risks his life). Men don’t tend to live as long as women do. Women are more intent on survival.

Outside of the human species, orgasm is infrequent and possibly absent among females of most species of mammal. (Alfred Kinsey 1953)