As many readers will know, Stephen Fry got himself into trouble recently when an interview was published in which he is quoted as making various observations about the natures of male and female, gay and straight sexuality. The interview is not currently available online, but if you wish to read extracts from it, then try The Guardian’s coverage for less than total hysteria.

The outcry over this has driven Fry off Twitter (again) and everyone is now weighing in with their own opinion. As ever, this debate boils down to the following trite observation – men and women, taken as groups, differ in some respects but not in others. Thus, those looking for a fight can make lengthy lists of the differences and rubbish those who emphasise the similarities, or can play down the differences and give endless examples of similarities instead.

But I don’t believe Fry’s personal musings should be cause for alarm or criticism. They were offered in no way as the last word on the subject, despite his possibly rather conclusive tone, and notwithstanding his subsequent claims to have been misquoted. And they seem on their face to be perfectly fair enough. It is a readily observable fact that gay men find anonymous sexual encounters easy to come by with no need to for money to change hands. That, further, while the world is crawling with prostitutes and rent-boys, the number of straight male escorts is vanishingly small (although there’s no shortage of straight men who would volunteer to earn a living in this way). That Playgirl magazine, launched at the height of the women’s lib movement and marketed to straight women is in fact read largely by gay men. Why should not a gay man venture some speculations as to the nature and cause of these obvious differences? Especially one whose non-professional opinion is eagerly sought on a very wide range of other topics – literary, musical, technological, cultural, sartorial, zoological – almost no subject is out-of-bounds where Stephen Fry is concerned, except for female sexuality apparently.

But it doesn’t take the brain of Stephen Fry to detect the obvious difference between the sexes which emerges after even the most cursory examination of the evidence, and which no list of thoughtful similarities will do anything to dispel. Men and women certainly do tend to process the world of sex and sexuality differently. In this post, I will attempt to give an explanation of why this is so, drawn from several different pieces of research, documentaries, pop science books and lectures I have consumed over the years. Regrettably, I find myself unable to footnote any of this very extensively, but if anyone really wants to take me on, then let’s head to the comments and/or the library. Most of this is logic, observation and common sense anyway. Let’s start from first principles.

Preparatory notion 1. Men and women are different and similar and diverse

For much of the rest of this blog post, I am going to be talking about men and women as groups, types or Platonic Ideals. But it’s perhaps necessary to acknowledge that a human man and a human woman will no doubt have far more in common than a human (of either sex) and a chimp. Or indeed, a dolphin, a racoon, a banana or a bicycle. It’s not that these similarities between humans don’t exist, they simply aren’t my topic for today.

And both groups are also terribly diverse. It’s certainly possible to identify women whose behaviour sounds much more like the prototypical male I am describing, or vice-versa. I’m not suggesting that each group is entirely homogenous, and that any particular man or woman you happen to meet (or be) is guaranteed to perfectly exemplify whatever behaviour I am claiming for that group. I am claiming, however, that certain behaviours are much more typically found in men than women, or the other way round, and I don’t want the presence of outliers to distract us from the interesting conclusions we can draw about the great majority, somewhere in the middle of the bell-curve. Once again, it’s not that these outliers don’t exist or aren’t interesting – it’s just that they aren’t whom I wish to write about today.

Preparatory notion 2. The mind evolved

The field of evolutionary psychology is excitingly controversial, although those who oppose the very idea of it, often seem to be to be attacking a straw man (as in this debate between Stevens Pinker and Rose). No serious researcher is taking the field to the absurd excesses described by those who seek to denigrate this approach, and like any scientist, evolutionary psychologists are free to speculate, while being careful to separate such speculation from evidenced conclusions.

But the basic idea that the mind evolved can hardly be denied. Tiny kittens play-fight to discover how to defend themselves and catch prey, but this play-fighting is instinctive, not taught to them. Birds hatch with all the required muscle co-ordination for flight and don’t require the blank slate of their brains to be written on by an extensive programme of schooling. Human infants learn to talk even when exposed to primitive and incomplete versions of what will become their native language, as in the deaf children of hearing parents who effortlessly turn the clumsy signs of the adults closest to them into the full linguistic richness of British Sign Language (or whichever).

Although humans are blessed with an extra capacity for general reasoning and abstract thought, compared to other animals, nevertheless much of what we do remains instinctive, unconscious and shaped by billions of years of evolution, rather than a few thousand years of culture. Thus we crave foods rich in salt, fat and sugar because moderate quantities of these things are essential to our survival, and they were not always easy to come by in the African savannah. If we failed to prioritise acquiring them, or passed up opportunities to consume them, we tended to be outcompeted by those that did. These being instinctive actions, shaped and promoted (though not actually controlled moment-to-moment) by our genetic makeup, a proclivity for aggressive consumption of salt, fat and sugar became the norm in the population.

Today, when foods high in salt, fat and sugar are readily available (at least in some parts of the world), this adaptation is no longer such a benefit, but evolution shapes us only slowly. We’ve needed salt to survive for hundreds of millions of years, but McDonalds has been in business for only a few decades.

Humans evolved around a million years ago. Hominids around 15 million years ago. Primates around 75 million years ago. Mammals about 250 million years ago. Tetrapods around 400 million years ago. Vertebrates 500 million years ago.

Sex evolved about a billion years ago.

So we’ve been boy and girl for almost as long as we’ve been anything at all. It’s not inconceivable that evolution might have shaped male and female brains differently, given a billion years in which to work. But we’ll come back to men and women once we’ve considered another more general point. We are now ready to begin asking some serious questions about sex and sexuality.

Question 1. How do we choose our mates?

Evolution isn’t only about survival of the fittest (which itself doesn’t survival of the strongest, or healthiest – “fit” in this sense means suitable or most fitting to the environment). Not just natural selection, the weeding out of the least fit, but sexual selection plays an important part. The price for sex (no we’re not still talking about rent boys and hookers) is that by reproducing sexually, I only get to pass on half of my genes. So I need to be pretty careful that my super-duper genes aren’t being dragged down by your inferior ones. Thus we get careful choosing of mates, display behaviour and phenomena like peacock’s tails. A peacock doesn’t need an elaborate tail for its own survival – quite the reverse, they are cumbersome and cost energy to maintain. But a peacock who can sustain this preposterous plumage must be, in general, a superior specimen, blessed with a robust constitution, excellent health and fitness and bags of stamina, at least some of which may be genetic in origin. Thus a discerning peahen who prefers to mate with the larger-tailed gentleman will find more of her genes in the next generation, whereas those who seek out the tiny-tailed may discover that the next generation is bereft of her genetic bounty since her offspring suffered from the same lazy attitude, heart condition or inherited disease as their dad.

Note that none of this is mentally considered by the peahen. It is simply a fact that because peahens who prefer to mate with big-tailed males have a greater genetic influence on the next generation, so  necessarily, the next generation contains a higher percentage of peahens who get turned on by big tails.

Quite obviously, even as sophisticated adult humans, with all our language and culture and technology, we also have mate preferences that we didn’t decide for ourselves, but simply woke up with aged about 10. And while it (once again) isn’t true that there is a single monolithic standard of beauty or attractiveness, patterns do emerge and so Marilyn Monroe is generally feted for her beauty whereas Bella Emberg received such compliments less frequently.

But even if we ignore the problem of establishing a global standard for attractiveness, we can still accept that people tend to rate people they meet in terms of how attractive they are – and we need not limit ourselves to physical beauty. A potential mate may strike you as attractive because of their power, charm, vulnerability, sense of humour, kindness, personal wealth, liking for adventure, exotic accent or any one of a number of other reasons. But, if forced to, you could give any person of the appropriate sex whom you happened to meet a rating on an imagined desirability scale. So if you should want a global measure, you can think of this as the average across all potential mates.

Sexual selection tells us that in the game of mating, those whose combined desirability scores are the highest are going to be those who most influence the next generation’s gene pool, and so evolutionary theory tells us that behaviour which tends to lead to this outcome will be selected-for and so come to dominate. That leads us to…

Thought experiment 1. The ice rink

You are one of twenty players (sexes are not relevant for the purposes of this game) who will shortly be let loose on an ice rink. It doesn’t have to be an ice rink, but freedom of movement is key. Each of you wears a number on your back, allowing you to be ranked in order from 1 to 20. Numbers have been assigned randomly and secretly, so – although you can see clearly what number somebody else wearing, you cannot see and do not know your own designation.

The game is to find someone who will agree to leave the ice-rink with you, holding your hand, and the aim is for each pair to attempt to maximise their combined score. So a 9 who leaves the rink holding hands with a 5 will score 14, but will be beaten by an 8 who leaves the rink holding hands with a 11. You can change your mind as often as you wish and the time limit is fairly generous so no-one is making any snap decisions.

The game begins. What is your strategy? The obvious (and correct) strategy is to immediately start looking for number 20. Regardless of what number is on your own back, nothing will give you a higher score than leaving with number 20 in tow. Pretty soon number 20 is spotted and quickly has a great many potential partners. There’s a 1:20 chance in fact that this will be you. So let’s assume it is – you are busily looking out for number 20 when you gradually realise that everyone else has come looking for you. You are number 20! Who are you now looking for? Well, the best score you can possibly get will now be 39, provided you can find number 19. So number 19 now becomes the only person whose hand you are willing to hold. 19 eagerly agrees to hold your hand, and you both happily leave the ice rink having won the game. But the game isn’t over yet.

Once 19 and 20 are paired off, all attention naturally switches to number 18, who is now the best prize available. Number 18 will now only accept the advances of number 17, and so on. By starting with the rule “maximise your combined score” we end up with everybody pairing up with the closest number to them.

Answer to question 1. People choose as their mate the most attractive person who will accept them.

Again, “attractive” is assumed to have a multiplicity of meanings, but this complexity doesn’t change the fact that we find some people more “attractive” than others – even if we couldn’t give a very satisfactory definition of “attractive” even when asked. And because we both seek and select, we reject people if we think we can do better, but set our sights as high as we dare. In life, unlike in the ice rink game, we get a sense of our own level of attractiveness (even if, or especially if, this changes over our lifetime) and so don’t bother approaching those way out of our league because the risk of rejection is suicidally great. When we encounter pairs who appear to buck this trend, they tend to be figures who attract startled comment. “What does she see in him?” and so on. This is precisely because they are outliers and not the norm.

Preparatory notion 3. Game theory can help us understand human psychology

Evolution finds solutions that “work”, where “work” in this sense can be taken to mean “increases the representation of those genes in the gene pool of the next generation”. Evolution in this sense is circular. Natural selection means survival of the fittest. What does “fittest” mean? Those who tend to survive. But if a subtly different shape of fin, a different trade-off in heart construction, or a thicker, shaggier coat creates a survival advantage, then over generations, a population of organisms will shift in that direction. Evolution tests countless tiny variations on the currently best designs and – especially if the environment changes – discards the ones which don’t help and retains the ones that do. It isn’t guaranteed to find perfectly optimal solutions, and if the environment changes very rapidly then evolution may not be swift enough, but when it works, this is how it works.

In just the same way, when it comes to sexual selection, evolution can generate variations on brain construction which give rise to different psychologies which give rise to different strategies. Those strategies which tend to maximise inclusive fitness – in other words those which don’t only aid survival for this individual organism but which contribute to their ability to genetically dominate future generations – will be selected for. But note that even homo sapiens is not granted a psychological makeup which is explicitly and consciously focused on inclusive fitness maximising. If it were the case that, for example, men were consciously focused on maximising their genetic representation in the next generation, that most men would be ferociously keen to donate to as many sperm banks as possible as often as possible – but this is not a solution which evolution could plausibly find. We would expect men to enjoy orgasm however, and this they generally do.

Of course, sex and reproduction is only worthwhile if you live long enough and so other forces come in to play. Some male mammals (although no females as far as I know) will eat their own young if food is scarce. The calculation (not performed consciously of course) is that if I eat my kids today, I can father lots more offspring when there’s enough food to go around. But if I don’t, I’ll die now leaving only this litter, who will probably die themselves. Layered on top of all of these evolved, primal, psychological forces are more recent, subtler drivers such as the need for acceptance, social status and so on, not to mention a whole other wealth of cultural, societal and fashionable forces which also act upon us, and all of that is without even mentioning all of the personal preferences which make us unique.

But game theory – the mathematical study of what tactics are most likely to lead to success given certain rules to play by – can certainly be employed to allow us to discover how evolution might have shaped this part of our mind. We can then look at human societies and behavioural norms and come to some conclusions about how many of these primal needs are preserved, and how many are muffled or eradicated altogether.

And here we must – for the first time – start considering men and women differently, instead of considering evolution, psychology, mate-selection and sex-differences simply as phenomena.

Question 2. What is a man’s best mate-selection strategy for maximising inclusive fitness?

Since the mind evolved, and since the mind evolved under this kind of selection pressure, we can be fairly sure that most men will be seeking a mate who is the most attractive person who will accept him. But maximising inclusive fitness doesn’t only mean finding a life partner. The potential cost of sex to a man is very little. He will never have to bear the child through pregnancy and the time which elapses between conception and birth may very well mean that he is no longer conveniently at hand to raise the child, or possibly no longer identifiable as the genetic father. But like a gambler with an unlimited bankroll, there is no reason for him not to keep rolling the dice again and again and again. Given the choice between having sex with number 18 and having sex with number 11, regardless of what number is on his own back, he would prefer number 18. But he’ll cheerfully have sex with number 11 if no-one else is around.

For men, promiscuity makes sense. Why would you not have sex whenever possible, provided you are still eating enough and providing a decent enough shelter to ensure that you will still be fit and healthy enough to have more sex tomorrow? There is no cost and from an evolutionary point of view, it’s an easy (and fun!) way to out-compete less eager rivals.

Not only that, but it’s also easy to see why men would prefer to have lots of sex with lots of different partners, rather than settling down with just one straight away and raising a family. All that time spent looking after your first child is time you could be spending anonymously fathering dozens more.

Question 3. What is a woman’s best mate-selection strategy for maximising inclusive fitness?

For women, however, the picture is vastly different. There is a tremendous potential cost for a woman in having sex with a man. This cost is twofold. Firstly, if she becomes pregnant, she will have six-nine months of discomfort, followed by many years of expending energy in childcare (this is a potential cost for a man too, as mentioned, but an all-but guaranteed cost for a woman).  The second cost is more subtle. Gestating this baby is a missed opportunity to gestate the baby of another man. Thus, because she wants her genes to be given the best possible advantage in the next generation, she will strongly prefer to have babies only with the most attractive men available.

Now, this is all very well if you are number 20. You simply wait for number 19 to come along, refuse to have sex with him until you have some way of forcing him to stick around and share the burden of childcare with you and give birth to a series of prodigious wonder-children.

But what about the rest of the population? You might imagine that the ice-rink experiment teaches us that number 12s just have to settle for living with and raising children with number 11 or number 13, but a better strategy exists for the female of the species. The possible lack of certainty about paternity here works in the woman’s favour. The very best strategy for all but the most desirable female is to find the most attractive male who will accept her, and then get him to help bring up the child which she gives birth to after having had sex with a much more attractive man.

Question 4. What evidence do we see of this in the modern human world?

This trio of observations – men and women each seek the most attractive person who will accept them, men favour promiscuity over a stable relationship, women need both a helpmate and a genetic mate but they don’t have to be one-and-the-same – unlocks a tremendous amount of human sexual activity, even though almost nobody actually gives totally free reign to these desires. From these observations we should expect to see – and do see…

  • Men are more likely to have multiple sexual partners, and will resist being “tied down” when still young and studly.
  • Women will be much more choosy about with whom they have sex and will be looking for life partners from a much younger age
  • Men will be very concerned about paternity and feel extremely threatened if it is suggested that the baby they are cradling might have been fathered by another man, unbeknownst to them.
  • Both sexes will be concerned about the possible consequences of infidelity on the part of their partner, but each will be concerned about different outcomes. Men fear cuckoldry. Women fear abandonment. As Steven Pinker puts it, women who discover that their man is cheating think “he’s having sex with her – oh god, what if he’s in love with her!?” whereas men who discover that their woman is cheating think “she’s in love with him – oh god, what if she’s having sex with him!?
  • Men, who are briefly deciding where to deposit their sperm before moving on to the next conquest, will tend to make the decision about on whom to bestow their genetic gift on the basis of factors which can be assessed quickly – chiefly physical appearance. Women, who are deciding at their leisure with whom to attempt to form a pairbond, will tend to weigh up a wider variety of factors before they commit to a sexual liason, including (but not limited to) trustworthiness, resourcefulness, kindess and so on as well as physical beauty.
  • And – as Stephen Fry noted – we should expect to see, and do see that gay men, genetically predisposed towards promiscuity but not having to play the mating game with women, will tend to be very promiscuous (despite the fact that no offspring will ever result from this behaviour).

Objecting that these behaviours are cultural rather than genetic misses the point three times. Firstly, it is surely not a coincidence that the biases we would expect to see thanks to evolution exactly coincide with our current cultural biases. Secondly, it entirely skips over the question of where these cultural biases come from.

Maybe because of these two (and I’ll come to the third in a moment) some who took offense at what Fry had to say simply deny that the behaviours listed above are remotely commonplace. Now, I’m not offering any particular evidence that they are, but they resonate profoundly with how men and women are depicted, talked about and represented. Offering a handful of outliers – as discussed earlier – does nothing to provide evidence that these very, very familiar behaviours are, on the contrary, vanishingly rare. It only offers evidence that they are not the totality of human behaviour. Fine. Nobody ever said they were.

And nobody ever said they were desirable either, which is the third way in which taking offense at Stephen Fry’s remarks misses the point. Simply because these behaviours are commonplace doesn’t mean that we should be happy with them, blithely accept them and even if we don’t like them, shrug our shoulders and say “there’s nothing we can do – it’s genetic.” Genetic tendencies are not implacable predestinations. They are powerful forces, but other forces certainly exist, and as thinking creatures with the capacity for abstract thought, rationality and selflessness, we can ask ourselves what kind of society we would like to live in and do what we can to bring that about.

And so, in many Western societies, attitudes – especially straight male attitudes towards women – are profoundly shifting away from what might be expected given these primal, evolutionary forces; but the shift is not, and I doubt ever will be, so complete as to eradicate any meaningful difference between the sexes. If you doubt that these evolutionary forces still act on our unconscious desires and behaviours, then consider this elegant study (sorry, no citation).

Researchers interviewed, took photographs of and took blood tests from a number of young women in nightclubs. From the interviews, they determined whether the women were single or in a stable relationship. From the photographs, they measured how much bare skin they were exposing as a percentage. And from the blood tests, they determined where they were in their menstrual cycle. The results were a strong correlation between fertility and skin exposure. The more likely they were to conceive tonight, the more flesh was on display. Their relationship status was almost irrelevant.

In all likelihood, not one of these women is making a calculated, rational decision to expose more skin tonight for this reason, and women being choosy in the way they are and for the reasons they are – both discussed above – even those dressed most provocatively may have failed to find anyone worthy to go home with, but this study does show I think at least one way in which our evolutionary legacy continues to influence our behaviour, whether we know it or not.

In a later post, I’ll explain why science can prove that there’s no such thing as bisexuality and why women genuinely don’t know what they want. If that doesn’t get you cross, then nothing will.

Mitch Benn by the Numbers
The difference between science and magic