Sperm Wars

by Robin Baker

  The result of these pressures is that women, like all female birds and mammals, are genetically programmed to be cautious and selective. In past generations, women who were not so were less successful reproductively than those who were. All women alive today are the genetic descendants of the more cautious of female ancestors, not their more reckless contemporaries. Men, on the other hand, are genetically programmed to be urgent and single-minded about one-off sex. In past generations, men who were not urgent and persuasive were less successful reproductively than those who were. All men alive today are the genetic descendants of the more urgent of male ancestors, not their more complacent contemporaries.

  We can see, then, that there is a big difference between men and women in the potential costs and benefits of a one-off intercourse. This difference automatically means that the two sexes approach any potentially sexual situation with a conflict of interests.

  A man can only satisfy his urgency if he can convince the woman concerned that she actually wants to be inseminated by him, now, rather than by him or somebody else, later. His only alternative is to try to force insemination whether she wants it or not. At first glance, it might seem that both of the boys in Scene 28 simply opted for the second course of action. Again, the situation is not that simple. The complicating factor is that male persistence in the face of female resistance can be a normal, mutually acceptable facet of courtship and foreplay. So, too, can aggression and a level of physical trauma. We are back to the way that women set men tests as an aid to mate selection – which brings us to the function of rough-and-tumble sex play.

  This is an emotive issue – so emotive that it is probably best broached by first considering the courtship of animals other than humans. For example, if we watch the courtship of dogs, we often see a clumsy male persisting and persisting with his advances despite rejection after rejection by the female. If we watch domestic cats we see females clawing, scratching and spitting at prospective suitors. If we watch mink, we see a male drawing blood as he tries to subdue the female’s spirited resistance.

  Witnessing such behaviour, it is difficult not to feel sorry for the females. At best they are being pestered, and at worst they are being physically damaged by males who refuse to take no for an answer. Yet, despite their resistance, female cats and dogs do eventually allow one of their persistent and aggressive suitors to mate. As for female mink, if they do not experience physical trauma at the male’s hands, they do not ovulate. Their bodies are on hold, waiting for the right male to inseminate them before they produce an egg (Scene 15). In all of these animals, female resistance is actually a test of male competence. Rough-and-tumble sex play in humans is similar.

  On average, men who are physically able to overcome the final defences of a female and achieve insemination leave more offspring than those who are not. So women whose sons and grandsons also have this ability will enjoy greater reproductive success. One of the criteria (Scene 18) that a woman can add to her list when selecting a mate, therefore, is his ability to overcome her physical resistance – but how does she test such an ability?

  Initially, she can simply watch him in competition with other males. The young men in Scene 28 spent much of their time chasing and wrestling with each other, doing their best to display their strengths and hide their weaknesses. But finally, the only real test a woman can set is whether a man can negotiate and overcome her own defences. To test this, she has to resist first verbally, then physically. The stronger and more realistic her resistance, the better the test.

  This is, of course, a dangerous game. Resist too little, and the test is meaningless. Resist too much, and the male may inadvertently cause real rather than superficial damage. The fact that courtship rough-and-tumble aggression rarely results in serious damage in cats, mink or even humans shows the accuracy with which this feature of sexual behaviour has been moulded by natural selection. Even in mink, the level of trauma that stimulates a female to ovulate is set at a level just high enough to test the male’s ability to overcome her defences, but not high enough for her to suffer long-term damage.

  In species such as humans which form long-term relationships, rough-and-tumble sexual behaviour is most important during the early stages of courtship. Once a woman has tested a man’s ability to force himself on her, she need not do it often thereafter. But as in all such tests of male health and ability (Scene 20), even within a relationship a woman gains from occasional reappraisal of her partner.

  Of course, in this as in most features of human sexuality, people vary (Scenes 35 to 36). For some, rough-and-tumble sex play is indeed a minor and infrequent element in their relationship. For others it is an essential element even up to the level of sadomasochism, if they are to accept the other person as a suitable partner. The dark-haired couple in our scene clearly leaned in this direction. Their intercourse on that first afternoon was rough, painful and humiliating for the girl, yet through the experience she recognised the boy as a compatible partner. In the years that followed, their sex life was to continue in the same vein – even once he was her long-term partner, she tested his ability to force her on many occasions during routine sex.

  We can now understand the decisions made by the two girls in the scene in the days and weeks that followed the events by the river. The boy who forced the dark-haired girl into intercourse passed her tests. She was already attracted to him, as were most other women, and her body perceived that his qualities made him seem a good candidate for giving her reproductively successful sons and grandsons. These qualities included physical power and sexual competence, qualities that her own characteristics made her well suited to test.

  In contrast, the other boy lost stature in his girlfriend’s eyes at all levels as the afternoon wore on. In part, he suffered by comparison. Mainly, however, he failed in an absolute sense to live up to his girlfriend’s criteria for acceptability. There were probably two ways he could have passed her tests, but he failed in both. The basic cause of his double failure was inexperience. First, with more experience, he would probably have opted for restraint and might eventually have gained long-term benefits (as, for example, did the experienced man in Scene 20 who, when faced with a similar situation, opted for patience rather than force and six weeks later reaped the reproductive benefits (Scene 26)). Instead, however, he opted for force. Even then, with greater experience at intercourse he might still have cemented a longer-term relationship and hence won many future opportunities for insemination.

  SCENE 29

  How to Con

  Outside the car, it was very dark and very cold. Inside, it was warm and getting warmer. After pulling off the road among the trees, he had left the engine running and the heater on while they climbed into the back seat. Now everything was warming up nicely. The girl’s breasts were exposed, her knickers were around her knees and his hand was between her legs in the warmest place in the car. She was struggling with the front of his trousers, and he was very excited. As he kissed and nibbled the side of her neck, his ear rubbed against the car window, cold and wet with condensation.

  Since acquiring his own car, six months ago, this was the third time he had been in this position. But on the first two occasions, each with a different girl, he had missed his chance.

  The first time, he had naïvely assumed that any girl interested in sex would be on the pill. She wasn’t – and she wouldn’t let him have sex without a condom, which he didn’t have anyway. He had pleaded with her to let him in, promising he would withdraw before he came. She said she had been promised that once before, would never trust a boy again, then immediately lost interest and asked him to drive her home.

  The second time, he had simply been taken by surprise. Offering a lift to a girl he scarcely knew, he had been amazed to find that before they were even half-way home he was being seduced into finding a quiet spot for them to enjoy themselves. They had been on the verge of intercourse when she suddenly stopped and asked him to use a condom. When he said he didn’t have one, s
he pushed him away. He offered to drive off and buy some, but she too had lost interest and had wanted to go home.

  With both girls, he had only the one opportunity for intercourse. Neither had given him a second chance. He had vowed never to miss another opportunity, and ever since his second experience had carried a condom with him. Now, two months on, with the foil around the condom looking faded and worn, here at last was his chance to reap the benefits of his hard-earned lesson. If he failed this time, it wouldn’t be because he wasn’t prepared – or so he thought.

  The moment came, and without even being asked he fumbled for the condom in his pocket. As he tore off the foil, the girl took off her knickers and got herself into as comfortable a position as she could. He pulled the condom out of the foil, perched it on the tip of his penis, and tried to roll it on. But it wouldn’t go. The condom just wouldn’t roll. He held it up in the blackness to try to work out which way round it should go, but could see nothing. He turned it over and tried again. He began to panic as he felt movement deep in his penis. The girl asked if he was having trouble. It was fine now, he lied, and with the unrolled condom still balanced precariously on the tip of his penis he moved into position and entered her without help.

  He knew the condom had come off as soon as he started thrusting, but he had been waiting for this moment too long to stop now. With supreme will-power he fought off the ejaculation that was so near as he entered and revelled in the excitement of an unprotected intercourse. Not until he went to withdraw, several minutes after ejaculation, did he tell the girl the bad news, feigning surprise as he pretended to search for the condom end with his fingers. The girl swore and, in panic, tried to find the condom inside her. In the end, with longer fingers and a better angle, it was he who found and removed the still unrolled rubber. He apologised profusely, admitted the possibility that he might not have put it on properly, but suggested that perhaps they had just been too vigorous in their love-making and she had pulled it off him.

  As he drove her home, he tried to argue that there wasn’t really any danger. The condom would still have stopped him from shooting the sperm into her womb and it did have a chemical on it that killed sperm. Even if a condom came off, he argued, it still worked like a cap. Being relatively naïve herself, the girl believed him. In the days that followed, he bought a supply of condoms and practised. At great financial expense, he practised until he could don a condom in any light, in any position, and with either hand.

  He never accidentally lost a condom during intercourse again, but did so deliberately on five further occasions, each time with a different girl and each time after they had once previously had intercourse with the condom properly in place. Each time, frustrated by the reduced sensations of wearing the rubber, he rolled the condom down such a short way that it came off almost immediately he began to thrust.

  None of these deliberate deceptions produced a baby. Four of the girls did not ovulate after their ‘accident’. The fifth did ovulate and her egg was fertilised. However, the ‘accident’ with the condom and the prospect of pregnancy and motherhood just before the most important exams of her life stressed her so much that, when the fertilised egg reached her womb, it passed straight through without implantation. When her period began, she went out to celebrate.

  Nevertheless, the young man’s misuse of condoms did make him a father, but through accident, not design. The mother of his child was the girl with whom he had accidentally first discovered the condom’s potential for gaining unprotected intercourse. Naïvely reassured by his story of the condom working like a cap, she had patiently waited for seven weeks for a period that never came.

  In Scenes 27 and 28 we have explored the way that young men and women have to learn various techniques in order to make the most of their sexual opportunities. In the modern world, they also have to learn how to use contraception. The young man in the current scene missed two opportunities for intercourse through his general lack of experience with girls. He nearly missed a third through his lack of experience with condoms.

  When we discussed family planning in Scenes 16 and 17, we concluded that modern contraceptives may have little impact on the total number of children a woman has in her lifetime. Nevertheless, they do supplement her natural methods of family planning, thereby giving her even more control over when and with whom she conceives. For a woman today, modern contraceptives are an important aid in her pursuit of reproductive success. Not least, they are a useful weapon in her manipulation of sperm warfare. In this section, we discuss the ways in which a man may also use modern methods of contraception to enhance his reproductive success.

  The idea of hindering or killing sperm as they leave the penis is not new. Over two thousand years ago, Pliny suggested rubbing sticky cedar gum over the penis before intercourse. The sheath has been known since Roman times and was in use in many parts of Europe by 1700. Fallopio designed the first medicated linen sheath in the 1500s, but the item took its name from the personal physician to King Charles II, the Earl of Condom, who recommended its use to the king as an aid to prevent the contraction of syphilis. By the 1890s, all of the barrier methods of contraception in use today were openly on sale in the United Kingdom. However, their use is unlikely to have been widespread until well into the twentieth century. In the 1980s, about 50 per cent of couples in countries such as Britain were relying on the man for their contraception. Only 30 per cent were using condoms; the remaining 20 per cent were simply using withdrawal.

  The perhaps surprisingly high incidence of withdrawal as a means of contraception during routine sex is in part a reflection of how men feel about using condoms. As most women can testify, if a man is expected to wear a condom during intercourse, he becomes much more cavalier in his attitude towards contraception. Of course, when asked why they don’t like using condoms, men say that they simply don’t enjoy sex so much with them on – the ‘Wellington boot’ syndrome. Women, on the other hand, tend to be much more favourably disposed towards them. This difference between the sexes in attitude towards condoms reflects a very important consequence of their use – by preventing sperm from entering the vagina, condoms negate a man’s reproductive benefit from intercourse much more than they negate a woman’s.

  This difference is less marked during routine sex than during casual sex. When a man and a woman are in a long-term relationship, the timing, spacing and number of children that are best for one partner are usually also best for the other. Consequently, an untimely conception would be equally disadvantageous for both of them (Scene 16). Since the use of condoms is one way that both partners can avoid conception, we might expect both the man and the woman to be equally appreciative of their use. Even in a long-term relationship, however, there is some difference between a man’s and a woman’s liking for condoms. Why?

  The main reason is that, as we have already discussed (Scene 2), conception is not the main function of routine sex. Such sex is the means by which a woman hides her fertile phase (Scene 2) while her partner tries to keep her topped up with his sperm as a defence against sperm warfare (Scenes 2, 4 and 6). Condoms do not spoil a woman’s subconscious rationale for having routine sex, but they do spoil a man’s. A woman can still hide her fertile phase via routine sex whether a condom is used or not. Obviously, however, if the sperm a man ejaculates do not take up residence in the female’s tract, they provide him with no defence against sperm warfare.

  It is not surprising, then, that even during routine sex men are consciously and subconsciously less enthusiastic about the use of condoms than women (Scene 17). Not least, men are much more likely to advocate taking the occasional risk.

  To understand why this difference in attitude is even more marked during ‘casual’ sex, let us first consider the pressures on a woman during casual sex and how these are affected by the use of a condom. As we have already discussed (Scene 28), a woman is normally more cautious and selective over casual sex than a man. All the same, having decided on a suitable time, place and part
ner, she can still gain a number of advantages from casual intercourse – as long as she doesn’t conceive (see Scenes 18, 20, 27 and 28). For example, if she is without a long-term partner, intercourse can help her gain a man’s attention in her search for one. In addition, she can use the intercourse to gauge a man’s sexual competence, potency, and to some extent health and fertility. Casual intercourse can thus be an avenue to protection and financial or other help from a man who she judges might be a suitable long-term partner. If she already has a long-term partner, casual sex with somebody else can provide a ‘reserve’ – a man to move on to if her current relationship breaks up (Scenes 16 and 19). None of these benefits from casual sex require her to conceive. In fact, she retains more options if she does not conceive. Only when she is specifically after a particular man’s genes (Scenes 6 and 26), or when she is trying to manoeuvre him into a long-term partnership by becoming pregnant (Scene 18), does she benefit from conceiving as a result of casual intercourse. Except on these occasions, therefore, a woman gains from the use of a condom during casual sex. Condoms even help to reduce one of the potential costs of casual sex, the risk of infection.

  Of course, a man also benefits in this last respect. Otherwise, though, the pressures on a man are quite different from those on a woman. We discussed these pressures in detail in Scene 28 in explaining why men are much more urgent, single-minded and cavalier over casual sex than women. Briefly, intercourse with as many women as possible is one of the main ways whereby a man can enhance his reproductive success. Each child produced in this way is a bonus to be added to that mainstay of his success – the children of a long-term relationship. A man suffers very few costs from casual sex that might erode this potential bonus. Harsh though it might seem, all each conception needs to cost him is a few minutes of his time, an ejaculate, and a slight risk of contracting a disease. If a longer-term relationship with the mother is in his reproductive interests, he may decide to offer paternal care. But if it is not, he may simply leave her to raise the child (or not – Scene 16) as best she can, while he pursues other sexual opportunities and seeks a more promising long-term relationship.