The battle of the sexes heats up and cools down, waves of 'feminism' rise and fall: but received wisdom regards human gender as a given: one of the pillars of the universe. Men and women are two sides of the same coin. No matter how they bicker, in the end and by and large they have to accept the complementary nature of their relationship, and get along the same old way... But increasingly this 'business as usual' worldview is maintained in the teeth of the evidence. In the course of the last century world-wide creation of wealth has been making insidious attacks, finally far more damaging than anything sexual-politicians can achieve, on the concept of gender. The lowering of the death-rate, high infant survival, improved standards of living, improved quality of life itself, all go to create a situation in which, inexorably, the human male's propensity for violence; and the human female's capacity for childbearing, come to be regarded not as natural facts of life but as problems, that threaten the prosperity and comfort of human society. And human history suggests that once we have perceived some factor in our world as a problem (whether it's the nature of the fixed stars, or the scourge of infectious disease) sooner or later, someone will come up with a technological fix.

(please note: this is an adult paper, containing material that may be offensive...)

For the last ten years, as a writer of feminist science fiction, I have been conducting a strictly amateur investigation into the nature and function of human sexual behaviour. I have approached the subject in different ways in novels, stories and critical essays; I've done a fair amount of reading around the area, and, like all good science fiction writers, I've taken note of developments in the real world. In the course of the decade, I've seen 'feminsim' as a broadly based political movement discredited, and I've seen it re-established as literary and academic forum with its own private squabbles, media stars and market-niche; an accepted cultural sub-group. I've seen women en masse rejecting radical political solutions, yet at the same time becoming more vocal, more visible; more conscious and more openly resentful of their disadvantages. I've seen the New Man defrocked, and the return of the unrepentant male supremacist. Yet at the same time I've seen emerging a global acknowledgement of endemic crimes against women -rape as a weapon of war, bride burning, domestic violence- that have been tacitly condoned, if not openly approved, for millenia upon millenia. As I try to grapple, in my fiction, with complexity and the tensions I see in the real world, I've found myself returning, in the exasperated way one tries to recur to the starting point of a quarrel, ad fontes (that means to the springs. It's Latin for let's get back to where this all started). Just what exactly is this thing called sex? What is it for, what is it supposed to do? This paper is a report on my investigation, and at the same time a description of how I, as an sf writer, go about the work of extracting ideas for my fiction from real world science.

There are quite a few popular science texts on sex around at the moment. It seems I'm not alone in my interest. Most of them (Richard Dawkins on The Selfish Gene; Matt Ridley's The Red Queen; Gail Vines' Raging Hormones ) are extended essays from popularisers with their own agendas: determined to challenge, rouse or excite their audience one way or another. These are 'sexy' books, as we say nowadays,. I preferred The Differences Between The Sexes, the published proceedings of the Eleventh International Conference on Comparative Physiology, held three years ago in Switzerland. The Differences Between The Sexes is a collection of original scientific papers, described as 'the first overview of this subject ever attempted'. This text does not set out to provoke anybody. The attentive reader can discern a whole spectrum of political opinion, faintly inscribed between the lines in these pages. But any special pleading is buried deep in pernickety scatter-graphs, and unlikely to stir the emotions unduly. Broadly, this is a book about sex as physiology, on every scale. There is no discussion of the symptoms or sensations of sexual arousal, only of chemical reactions. The organisms or body parts involved - lizards, ants, elephants, fishes, possibly parasitical mitochondria, Mullerian ducts and avian W chromosomes, are not perceived as doing sex for pleasure. They do it for exclusively economic reasons. But don't imagine that this makes for a dry and dull textbook. The sex-for-money story here is possibly even more fascinating than the one you find in the more familiar tabloid context.

So, exactly what do we - represented by the international science community - know about sex, at this stage in the game? Let me refresh your memories on modern sex-science lore. We know that eutherian mammals -that's animals like us- with the XX or XY sex chromosome pair, are default females. Hence the expression mammals, animals with milk-producing breasts. So, if you castrate a male rabbit embryo at an early stage in its development it doesn't grow up sexless, it develops as a normal female. (This is charmingly called Ohno's law, after Susumu Ohno, who first proved it). Whereas birds, with a ZZ or ZW pair, the W being the female chromosome, are default males. Thus, if you feed a peahen male hormones, she gets a bit pushy and irritable but physically nothing much happens. If you suppress her female hormones, she grows a flamboyant peacock's tail. The 'cryptic' or dowdy plumage of the female in bird species is not a deficiency, then, as we have intuitively asumed. It is a positive interference in the natural course of things. Marsupials, or non-eutherian mammals, don't fit into this scheme of the chromosome pair sexing. They're a peculiar lot.

We know that gonadal sex, the development of testes or ovaries, is normally determined in eutherian mammals at conception. All other features of sexual dimorphism -external and internal organs, differences in brain structure and body size, all sexual behaviours, are produced subsequently by the action of the gonadal steroids, (progestins, androgens and estrogens), powerful chemical concoctions that are carried in the circulation to act throughout the body, including the brain. It's as you long suspected, you're not responsible for anything you do under the influence of sex, it's just a drug experience. Marsupials, however, don't work quite the same way....( But I can't begin to tell you about the marsupials, it's just too bizarre. You wouldn't believe me. You'll have to read it for yourselves).

What else could I mention? There are the parthenogenetic species, animals that consist naturally of female individuals only. (It's not suggested that they evolved out of the pre-Cambrian stew like so: they have separated off from gonochoric, that is sexual species, somewhere along the line). Some of them mate with males of related -sexual- species, and have various means of using or discarding the sperm DNA after conceptions. Some produce eggs without any genetic recombination at all: they're obligate separatists. I think the most famous of these species, the Texan parthenogenetic whiptail lizards studied by David Crews of The University of Texas, Austin, have passed into popular-science folklore, so you'll probably know that all-female lizard species exist. But did you know that individuals of these species have a habit of copulating with each other, taking turns at adopting male or female roles - a behaviour which has a measurable impact on sex-hormone expression and on breeding success? The act itself has only been observed in captivity (there are some delightful photos): but the butch partner's role includes inflicting neck-bites, severe enough to produce a lasting bruise. Wild animals picked up for examination have been found with exactly similar hickeys on their throats, so it looks like it's not just the decadent lab-cage trollops, they're playing butch and femme out on the range too.

You may have heard of the SRY gene (sometimes written Sry). That stands for sex-determining region, Y gene. The definitive, universal marker that makes males male achieved national news status when the discovery was announced a year or so ago. The detective story of the hunt for SRY is in here: a paper by Jennifer Graves of Le Trobe university, Victoria Australia. It's truly fascinating. But there's also, hot from the press, research that has unearthed some 'bizarre rodents' -the Iberian mole vole, the Kamchatka wood lemming, the Amami spinuous country rat- where maleness is not determined by the SRY, and maybe even not by the XY pair. The hunt for the actual, holy essence of la difference isn't over yet.

What else? There's a paper on sexual dimorphism in primates, presenting evidence from skeletal analysis that female proto-gorillas, humans, chimps, may have been hunky as the males. Rather than males being selected out for larger size and strength, the females may have been selected down to a smaller bodysize on the grounds of reproductive success. This is one of the papers where a quite provocative point is hidden in the scatter-graphs. It is a basic tenet of male supremacist thought that humanity is naturally unequal, because men have always been the big strong owners of harems of docile little females... It gives them legitimacy. ( I do not see it myself. If someone knocks me down because he's bigger than me, and then explains its okay, because he's been bigger than me for two million years, I don't feel any better about it at all). But it's quietly done: no excitement, no politics, just a modest suggestion that you take a look at the figures.

There are the female to male and male to female transsexual fishes. You'll have heard of them, maybe. They've passed into popular science folklore along with the Texan lizards. It appears that in many species of fishes if you remove the dominant male from a social group, the largest female then becomes male. In other circumstances, fish that are born 'male' become female. Douglas Shapiro and others, of Michigan have been investigating this phenomenon. They've discovered that sex-change is not destiny. The female to male or male to female change isn't inevitable in a simple set of circumstances like 'remove the male'. It is triggered by a particular and complex interaction of social and environmental factors: broadly, only when it's going to be profitable. You've heard of Sexual Darwinism. Here you get a classic, beautifully explained study of the precise economic factors that lead an individual fish to 'decide' -speaking anthropomorphically- to change that mumsy apron for the go-getter's posing pouch.... .

There's sexually differentiated liver-function in rats; featuring mind-boggling lists of steroid metabolizing enzyme activity. There's a paper on song-control brain area dimorphism in the nucleus hyperstriatalis ventrale in male canaries; as opposed to male and female zebra finches -a duetting species -; re-assessing the significance of sexually dimorphic brain structure, and the relationship of brain-area volume to efficient function. There's Drosophila melanogaster pheromones (you can't leave out the fruit flies). And much, much more.

I don't think I have to apologise for reading Differences Between The Sexes politically. I am, sincerely, in awe at the quality of some of the papers (so far as an amateur can appreciate them). But I'm a science fiction writer, not a scientist. I approach these essays as I would an article on the curious plight of Hubble's Constant. I'm looking for hooks and riffs; material I can use.

It's no surprise that the picture isn't much altered from Aristotle's view of the sexes. (The relevant quotation is provided in translation in the front of the book. I thought that was a stylish touch -ad fontes indeed ). Cosmologists can add or subtract a few billion years from the age of the universe at will, without colliding with commonsense. Sexual dimorphism belongs to a different order. Male sexual behaviour, generally, is aggressive and dominant. Female sexual behaviour, generally, is submissive and compliant. This is what we know, this is what we see. The advent of electron tunnelling microscopy is not going to reveal, suddenly, that it's female red deer that grow the big antlers, and start beating the shit out of each other every September; or that male elephant seals are the helpless victims of institutionalized rape on the beaches. There are some popular sex-science writers who take violent exception to Aristotle. But they are no use to me. I'm never interested imaginative interpretation with my science. I only have to pick it out and leave it on the side of my plate. I provide that element for myself.

The editors of The Differences Between The Sexes are less radical than some of their contributors (to the extent that R.V. Short, in his afterword, declares that " nobody questions the significant differences in average weight, height and strength between men and women, testimony no doubt to our polygynous past..." apparently unaware that Robert Martin and others, the primate body-size snatchers from Zurich, have done exactly that). In many of the papers one can discern a fashionable shift in concept from simplicity to complexity, from clear results to fuzziness. Thus, in the primate-size paper Robert Martin and his team do not claim that the theory of the big, polygynous male ape and human ancestor is wrong, they present evidence for a more complex situation. Science becomes a palimpsest, not a single text: it becomes, in some ways, a kind of fiction. But though trends in modern science have a discernible influence there is an old-fashioned anti-radical consensus in these papers, a commitment to pure description -as far as humanly possible- above interpretation, that gives me confidence. I can work with these results, without much hassly filtering out of contaminates.

The scientific version of the sexual politics debate can be summed up roughly thus: Are animals individuals, whose behaviour is affected, marginally and circumstantially, by sexual function? Or is sexual/reproductive function the essential, defining core of the organism? You'll find one or other view expounded, with more or less of tub-thumping self interest, by writers like Richard Dawkins, Matt Ridley, Elaine Morgan, Gail Vines. The editors of Differences, in their separate afterwords, neatly represent the opposing camps. The papers tend, if anything, towards the former position. What I find in The Differences Between The Sexes is a general chipping away at the area that can be labelled male or female in physiology and in behaviour; and a shift in concept from sex-specific to sex typic. "sex-specific behaviours are numerically a minority. Most sexual behaviours are 'sex typic' meaning they can be produced by either... but are shown more frequently in one sex." (Manfred Gahr: Brain Structure: causes and consequences of brain sex). But the sex-is-destiny argument is also supported. Sex difference is largely malleable, but it is unambiguous. There is no sliding scale in behaviour, function or identity: it seems we are dealing with a switch, not a dial. There is male, and there is female. The identities may be confused by a genetic copying error, or successive in a single lifetime, or (in terms of behaviour ) learned, unlearned, alternated, adopted or simulated at will: but they are always distinct.

The investigation is fascinating. I'm equally interested in the fact that it exists at all. There was a time, quite recently, when popular science books about sex were how-to manuals with soft focus covers; or collections of prurient statistics about the sexual habits of people who like talking dirty to market researchers. In the last few decades, technology has made the secrets of reproductive function accessible as never before. The mystery of sex can be examined, it can be taken apart. There are signs of a development that is familiar in the history of science. A set of phenomena that was a puzzling given: not even a locked box but apparently a solid block, has changed its nature. Jupiter has moons, the atom has internal structure... As we know from previous experience, this is a precarious situation. Once we start taking something of this order apart, we never manage to fit the pieces together again, quite the way they were before.

I'm not sure how far the general public participates in scientific revolutions. There's a theory that thought gets into the air and worries people -so that the individual human animal in the street eventually starts to feel uncertain about Heisenberg's uncertainty principle, or kind of stretched by the implications of general relativity. There has been a wave of female emancipation recently, it's true, and over these same decades. But there've been waves of female emancipation before, and nothing much happened. As I remarked in my opening paragraph, the evidence is that most people actively enjoy the battle of the sexes. They do not want a sexual reconciliation. However, in this context it's interesting to note the recent career of the term gender. Does gender, which means difference, mean the same as sex? Increasingly, and to the irritation of pedants, people are using the terms as if they're interchangeable. ( I called this paper 'on the future of gender'. On disc it's called SEX, because it's shorter). We talk about gender roles, gender-studies, gender-politics, gender-related issues. Irate terminology-watchers ( for instance Richard Dawkins) demand indignantly If you mean sex, why don't you say so? What is this decadent newspeak !! I suspect that people may be becoming increasingly aware that they don't mean sex, when they say gender. When you are asked to check the box on the form, the question's not about physiology, it is about social role: about difference. You are not being asked do you have ovaries? You're being asked, are you going to stay at home and look after the children? Or, to put it another way: if we give you this job, are you going to work for three weeks and then take an extended career break at our expense, to indulge your sociopathic addiction to child-bearing..?

Sexual behaviour is malleable. Sex-hormones are mind-altering drugs that can be used by anyone, female or male. If I dose myself with testosterone, I will become aggressive, non-altruistic (and hairy) as any genetic male. We know this can be done, and we can be sure it will be done. Because if there is one thing we know about animals, whether they're whiptail lizards, nematodes or humans, it's that if an animal once finds it can do something, and profit ensues, then it will do that something, though the heavens fall. ( this is called evolution). We can adjust our sexual behaviour, and thereby our social roles. We can't - not yet - alter reproductive function. The option of having no children is now available to sexually active women as never before: but no hormone treatment will turn a man into a fertile woman. However, reproduction, as instanced by that job application dilemma, is not strictly the issue. It can be argued that since human females don't experience oestrus, sex has always been primarily a social activity for our species, engaged in for social benefit, from the point of view of the selfish individual human animal. (Leaving the selfish gene a helpless hitchhiker on life's journey). Most certainly now, more than ever, it's social function that matters.

Animals do sex for money: for strictly economic reasons. 'They choose' the sexual behaviours, weaponry, body-size; and, where feasible, the sexual identity, that 'they believe'-- to personify a complex of highly impersonal factors- will ensure greatest reproductive success. That's Sexual Darwinism, and as scientific theories go, it seems to work. Without reproductive success - on a mega scale - humans wouldn't be where they are today. But more and more, for selfish individual human animals both male and female, reproduction is not money. Money is money: is status, territory, resources. According to the science in The Differences Between the Sexes, we will all adjust our sexual behaviour accordingly.

The world is overpopulated, we should all be having fewer children. But women who have more economic rights than every before -in this country for instance, and in other rich countries of the white north- see childbearing as another kind of access to money: which they have a right to enjoy. Meanwhile nationalists in China, in Africa and in the Balkans are controlling women's fertility for the ancient, animal reasons and on a genocidal scale. Femaleness is in trouble. Maleness is no better off. All over the world, men are having to compete directly with women in dominance ranking contests: in parliaments, in the job market, in the media - a situation which they find very disturbing indeed. In the world at war, ordinary, natural male-competitive behaviour - killing the defeated rival's offspring and impregnating his females - is suddenly stigmatised as criminal, just when the competition's getting really fierce. It's enough to drive a species crazy... I do not say that 'sex' is suddenly a problem. The conflicts between male and female interests are the same as always. The problem, perhaps, is that there is now a solution, of sorts, available. If sexual behaviour and function are malleable, and yet sexual identity, difference, remains obstinately intact -which is what the science predicts and what we see happening around us- then we don't have two complementary sexes any more, each safe in its own niche. All there is left is gender: an us and them situation. Two tribes, separated by millenia upon millenia of grievances and bitterness, occupying the same territory, and scrabbling over the same diminished supply of resources. This is the situation, the riff that I've found and used, and which you'll find explored in my novels White Queen and North Wind. But I'm a writer of fiction, a composer of metaphors and myths. My novels, in the end, are not predictive. I don't do prediction. The difference between me and the writers of The Differences Between the Sexes, is that their proposals are open to further investigation, re-assessment, the development of new and more searching experiments. I can be plain wrong, and it needn't affect the value of my work at all. I certainly hope I am.

I 'd like to say more about the future of gender... There are philosophical considerations, suppose we manage not to tear each other apart. Animals do sex for money: Humans also think, and this concept of difference: either/or, same/not same is immeasurably important to our thought.. How deeply is our sense of the other bound to our sexuality? This is another aspect of the gender question, that has been tackled in various ways in feminist science fiction; and continues to be explored. What happens to that crucial image of the other - the face opposite, the self that is not-self - if the importance of sex begins to be eroded? But that's a whole new question, and beyond my scope at present.

You may be wondering what happened to the brains of female hyenas. It's another strange but true sex-science story, not actually featured in Differences, but recently in the pop-science news, about testosterone use and abuse in the animal world: but I had so many, that I forgot to use it. Anyway, it's a great book. Highly recommended.