Some Christian theologies are dualistic, separating body and spirit and condemning things of the body as sin. At other points, some Christian theologies have viewed things of the body as immutable gifts of God and therefore not to be disturbed, except for healing that is defined as returning the body to its natural state. This book approaches the body in simpler theological terms. It makes no presuppositions about the inherent goodness or badness of the body except to note that life is a good gift of God. Neither is there a presupposition about immutability. Instead, the first thing to note is that the body exists. This means that if we want to say something theological or ethical about the body, it would be a good idea to understand what the body is and is not. The second step is to ask what the body makes possible and to consider the desirability of the alternatives as measured against Christian standards such as love and responsibility.

There is one theological choice that is worse than dualism or regarding body elements as irresistible psychological, social, or spiritual forces. It is to simply ignore the body. Any of these three options earns theology a lot of laughter as a pompous irrelevance. The solution is to remember that Christian theology can trust the truth, with appropriate humility about our grasp of the truth. Respect for scientific sources of truth can help us frame life's most important questions with as much groundedness as we can muster. With God as creator, and Jesus understood as incarnating God's presence in the world, Christians are drawn to an interest in the embeddedness of spirit in the midst of life. This is good Christian grounding for both caring about and respecting what science can tell us while remembering what science cannot tell us because of the properly imposed limits of scientific inquiry.

Many people are most comfortable in scientific discussions of human beings when they reason from body causes to social and cultural effects. In everyday terms, people are prone to say things like "I behave this way because I was born this way. Other people are heavily invested in denying physiological determinism, in making logical space for the causal relevance of environment and nurture. This chapter takes an interactive approach, understanding that our bodies influence our lives and that social forces and personal choices can affect the body. Another way of saying this is that you can't have a life without having a body and that there is more to life than having a body.

Typical scientific theories and research efforts are analytic. The word analysis derives from the word cut. Analytic thinking cuts the object of study into its constituent parts. When the parts have been identified, and when the processes by which the parts become a whole are identified, analytic science has accomplished what it calls explanation. In physiology this means identifying the parts of the body and how they function together to be a body. When a body part has been identified, and when its effect on the whole body has been identified, then this kind of science has explained the causal impact of this body part.ii

Analytic thinking, however, is only one alternative for those who want to take science seriously. Synthetic scientific thinking works with the same observational base as analytic science but understands what is going on somewhat differently. The key to the corrective power of synthetic thinking has to do with understanding what is observed and what is not observed.

Whatever the object of observation for any particular science, what is observed in the object is what is manifest. What cannot be observed about the same object is its potential. When a particular object is observed as it interacts with other objects, we can observe a potential that becomes manifest in the interaction. The key point of synthetic thinking is the understanding that this newly realized potential is part of a more complex whole. The interactive potential of an object is realized only as it interacts with other objects. Although it is fair to reason that the potential to participate in a more complex manifestation is "in an object as that objects stands alone, it is equally fair to reason that such potentiality is not being accounted for when the object is viewed alone. When an object is considered by itself, its potential is known inferentially from previous observation of the object in interaction. Synthetic thinking shows us that any object is more than the sum of what can be observed in its parts when those parts are observed separately. The "more than is the hidden potential that is revealed as the whole object interacts in a more complex frame of reference. This is the core correction of the common error of scientific reductionism, such as reducing the concept of mind to the physiological base of the brain. Physiological reality is a basis for all human activity but not necessarily the most significant cause of human activity. This point which will be repeated at several places in the book, is one critical element for understanding why transgender experience and expression should not be understood as pathology.

Consider a synthetic understanding of water. Water is made up of two atoms of hydrogen and one of oxygen, which meld together under certain conditions. Although we know that hydrogen and oxygen can combine to become water, we cannot observe the wetness of water in hydrogen or oxygen in isolation. It is easy to skip over this point, because we "know it is there.

The core physiological questions to ask about sexuality and gender concern the physiological bases for sexuality and gender: what is limited, what is likely, and what is possible when we observe people in terms of their psychological identity, their social role behavior, and their relationship to cultural symbols. We know that there are physiological limits to life itself. We know that physiological states affect, and in some cases can overwhelm, our consciousness or our feelings. But to point out that there are physiological limits to our sexuality and gender is like pointing out that water can freeze at certain temperatures. It is valuable knowledge, but it doesn't help us understand what is going on when water is in the temperature range of wetness.

Mood altering drugs can profoundly affect human consciousness, human feelings. But this doesn't make the mood equal to the drug. Within usual "temperature ranges, other factors also affect mood or feelings, and such mood or feelings can take part in a much more complex whole of identity or choice. One can drink too much alcohol and die, less and fall into a drunken stupor, less and be substantially impaired, less and be happily drunk, less and be slightly relaxed. To deny the potential effects of drinking alcohol is dumb. To say that drinking alcohol will kill you, without specifying dosage levels and other circumstances, is a falsehood. It is equally dumb to think that one can fully explain drunken behavior, an intrinsically social observation, by explaining the alcohol level in the blood. The alcohol level in the blood affects the possibilities and limits of human behavior, but it does not explain how people will feel or what they will do within such limits. Different people do not feel the same, or act the same, every time they consume enough alcohol to raise their blood alcohol level to a specific point.

The consideration of the physiological aspects of human behavior in this chapter is important for beginning to build a scientific picture of the phenomena of transgender experience and expression. This consideration is also important because a great deal of contemporary political and spiritual thinking about transgender experience and expression refers to physiological facts and theories. Sadly, it is too often the case that both sides of a political or spiritual argument may grossly misunderstand the science to which they refer and may give far too much importance to physiological factors in the overall picture of scientific explanation. Such mistaken arguments often fail to note the limits to generalization and applicability that are the boiler plate of scientific reporting. Another common error is to reason metaphorically from the scientific base rather than to reason logically. Metaphoric thinking can be quite useful. One just needs to keep clear that it isn't a substitute for analytic or synthetic thinking when a scientific point is being made.

To show the relevance of sharpening our physiological thinking it is worth noting, for example, that many political and spiritual arguments about sexual ethics turn on the scientific understanding of the word choice. For example, Presbyterian ethical statements about homosexuality distinguish between orientation and conduct and assert that homosexual orientation is acceptable because it is not chosen, whereas homosexual conduct is sinful because it is chosen. This chapter on physiology will try to lay a proper grounding for understanding the issue of choice and similar questions.

People have 23 chromosomes that contain a total of 70,000 to 150,000 pairs of genes.iii Each chromosome is made up of two genetic strands. In the 23rd chromosome the two strands are markedly different: XX in females, XY in males. Except for the 23rd chromosome in males, in each chromosome a gene is represented on both strands though the paired genes are not identical in form and effect: among other things, one gene may be stronger or weaker in effect than its paired gene.iv

Our understanding of the complexity of genetics has expanded enormously in recent years. Many of us learned to think of genes as a blue print for our physiological development, and this image still may be compelling. To more adequately understand the blooming complexity in contemporary genetics, consider the following:

• . Any gene may have different forms, called alleles. Sometimes, only one allele of a gene is the source of a specific trait.
• . There may be several forms of a particular allele, depending on how often certain sub-sequences of genetic chemicals are repeated. Different forms of the allele may have different physiological effects.
• . It can matter, in terms of effect, whether a specific gene is inherited from the father or the mother, even though the structure of the two genes appears identical.
• . A gene may be dominant or recessive, and some dominant genes are recessive under certain conditions.
• . If a gene on one chromosome doesn't work then the matching gene on the other chromosome may kick in, but at a different level of effect.
• . Genes work interactively with other genes to shape a particular effect. For example, variation in a single gene can create the unusual shortness identified with an African tribe labeled "Pygmy. But, if that gene is in its most common condition, then many genes will affect height.
• . Different alleles may have different penetrance or power in interaction with other genes. For example, you might have the allele for a particular genetic disease, but the disease will not become manifest because the allele's action is suppressed by other genes.
• . Genes are considered to act in terms of probabilities, and some genes are never active.
• . Many genes that affect development are active only for a limited period of time, except that sometimes, for certain cancers at least, they turn back on. Some of the most interesting theorizing about the genetic basis for sexual orientation (gay men in particular) concerns genetic action during fetal development.
• . A single gene can have several physiological effects: a "negative effect (sickle cell disease) may be carried along through inheritance as the other side of the coin of a "positive effect (resistance to malaria).
• . Mitochondria, the elements in all cells that release the energy of combining oxygen and carbohydrates, have their own genes which are passed on independently of the chromosomal genes. The mitochondria are also critical in the first stage of the process of converting cholesterol to sex hormones.
• . Genes produce their physiological effects by creating amino acids in specific patterns that make up complex proteins. This process can be altered by other physiological factors.v

For the above reasons, highly similar genetic structures will not always produce the same physiological outcome. Anne Faust-Sterling summarizes much of the above argument by pointing out that genes are small bits of organic matter in a cell that interact in enormously complex ways with other elements of the cell and that some of those other elements in the cell enter from the outside.vi Understanding these multiple complexities has helped us understand why "identical twins, as close a genetic similarity as occurs naturally, are not really identical. For example, if one twin is left-handed it is more likely that the other twin will be left-handed than a non-twin sibling, but the other twin will be left handed less than half of the time.

The fact that the 23rd chromosome occurs in a female form (XX) and a male form (XY) does not mean that males and females are brightly differentiated genetically. First of all, males and females have 22 pairs of similar chromosomes and only one pair that is XX or XY. The Y chromosome is comparatively short and is currently understood to contain the genes that create male changes in development and very little else.vii This fact alone should be enough to end the common phrasing about the "opposite sex. Mary Coombs, a University of Miami law professor, a feminist theorist, and a lesbian theorist, recently wrote, Frankly, I'm not sure what something the opposite of me would be, but it's not a male human. Perhaps a Brussels sprout?viii

A tour through the development of genetic science is one of the several joys to be experienced by reading Chandler Burr's A Separate Creation: The Search for the Biological Origins of Sexual Orientation.ix Burr uses a political analysis of the development of genetics as a scientific discipline to focus on issues of sexual orientation. His work attends primarily to the issues of gay men, and gives only a little attention to transsexuality and none to transgender expression. The central point about genetics that Burr illustrates so superbly and readably, is that genetics is enormously complex and interactive. The several aspects of physiological reality that we label male and female are complexly shaped at the genetic level. This explains why any specific physiological structure may be differently shaped in different people and may be stronger or weaker in its effect on the rest of the body in different people.

Burr tells the story of the first "discovery of a gay gene by Dean Hamer and his research team. Hamer and his group published their ground-breaking research in 1993, "A Linkage Between DNA Markers on the X Chromosome and Male Sexual Orientation.x Hamer and his team did not actually find a specific gene for male homosexuality but rather identified a narrow genetic region where such a gene is likely to reside. Neither did they demonstrate the physiological effect of a gay gene. Neither have they shown the distribution of this gene in human populations. We do not know whether the penetrance of the theorized gene is strong or weak, or whether the physiological effect is strong or weak, or whether the gene might have several strengths in several alleles. Neither do we know how this genetic effect interacts with other genetic effects. Only simplistic blueprint thinking would lead us to conclude that Hamer's research points to a physiological limit, or an overwhelming physiological urge, that overrides all other factors in the explanation of male homosexuality. Hamer does not make such a claim, and Burr is careful to point out the multiple qualifications and caveats that Hamer presents. Although Hamer's research is appropriately cautious, and although he understands that many other causes may be relevant, both sides of the argument about choice quickly jumped to conclusions based on one or another understanding of genetic determinism.xi This is like arguing that our genetic capacity for language determines whether we will speak French or Chinese.

Hamer's team also spent time doing sociological research in an attempt to identify the trait of male homosexuality so they could specify what they were studying. This research had several methodological problems, which are discussed later. What is important at this point is that Hamer's team ended up recruiting subjects for their genetic research by advertising in gay newspapers. There is nothing scientifically wrong with using such a convenience sample for genetic research. The logical problems come from generalizing results about the effects of the presumed gene from a limited sample either to a larger gay sample or to the general population. There may be a lot of difference between males in the general population who have some homosexual experience and those who would answer Hamer's advertisements. While Hamer was careful to note that the gene they are on the verge of identifying may contribute only a small element to the explanation of sexual orientation in some men, popular writers were quick to talk about the discovery of the "gay gene as if it were dominant and relevant for everyone.

Some of the genetic qualifications relevant to Hamer's study include the following: more than one gene is likely to be involved, which means a genetic base for complexity rather than simplicity. The effect of inheriting a single gene at conception may be radically modified before it in turn affects development. This finding is considered by some a likely explanation for the fact that even a monozygotic (identical) male twin has only a 50% chance of being gay if his brother is gay. Such twin studies are a good reason for arguing against a tight genetic determination. Twin studies show genetic relevance, but they also show that the effect of genetic inheritance is not so simple. If a gay gene is finally differentiated, it will take additional research to show how such a gene influences development.xii

Hamer's research is directed to finding a specific gene (needle) out of 70,000 or more genes (haystack). He writes, "The overall machine which you could call sexuality, may be, genetically, incredibly complicated, but the directional switch for that machine, straight or gay, may be incredibly simple.xiii The terms directional switch and machine show that, for Hamer, all the boilerplate qualifications he appropriately included in reporting his research don't really matter to him. At heart he believes in a mechanistic and deterministic genetics. In writing this book I take the boiler plate seriously, both the complexity at the genetic level and the complexity of the experience and behavior to be explained.

Burr follows Hamer and other physiologists and repeatedly argues for "biological essentialism, particularly that a gay sexual orientation is not a matter of choice. Although Burr's essentialist commitments may account for his interest in genetics and anatomy, his book nonetheless makes it abundantly clear that the current state of physiological research cannot support a position of narrow genetic determinism. I salute Burr for his careful report of Hamer's research and follow-up interviews which undermine a deterministic position.

In addition to the impressive achievement of demonstrating a narrow region of a chromosome which may contain a gene that has some influence on gay activity by some men, Hamer also was able to suggest that such a gene is probably recessive and is probably passed through mothers. However, assuming that Hamer and his group have discovered a gene that is statistically more common in a sub-sample of gay males than in the general population, that is still no proof that the gene causes something in a person that affects sexual orientation. Most genes are inactive. They don't do anything at all. If the gene is active in some way that is related to a subsection of the gay male population, there is no proof that the gene is causative rather than a mere corollary of gayness. Even if the gene proves to be active and influential for the sexual orientation of some men, because the gene is recessive and broadly distributed in the population there is no way an antigay eugenics movement could eliminate gayness by controlling reproduction.

Growing Up


Genesis got its physiology backwards: at conception everyone is on a track to develop as female. Later in fetal development those who have an XY chromosome (males) usually develop high levels of two hormones: testosterone and MIH. The MIH leads to defeminizing development. Thus males usually have only the vestiges of ovaries, uterus and vagina, found near the prostate gland. High levels of testosterone leads to masculinizing development in XY fetuses. Females (XX) also generate testosterone in their ovaries, adrenal glands, and elsewhere, and it is critical for their development. Sometimes XX fetuses also have a masculinized development because of a high level of testosterone.

There are reasons to think that the transition from female to male is not so easy for the developing XY fetus. For one thing, at conception there are 130 XY fetuses to every 100 XX fetuses. At birth the ratio is almost equal. Those scientists who argue that there are physiological causes for gay and lesbian experience and expression, or for bisexuality or transgender experience and expression, often argue that something goes wrong during pre-natal development that either masculinizes the brains of females or feminizes the brains of males. Never mind that such an outcome hasn't been found in adult brains. (See the later section in this chapter on brain development.) Never mind that there is no direct evidence for this theory in human subjects. Never mind that the choosing of sexual partners is only one aspect of being a man or a woman and that no one has demonstrated a general relationship between masculinity or femininity and choice of sexual partners. This theory seems to be so culturally needed that scientific assessment is almost irrelevant.

Just because genetic or physiological determinism hasn't been proved doesn't mean that there is not lots of relevant evidence. Indeed, pre-natal causes of homosexuality is one of the most studied of all research theories in endocrinology. Those who summarize and interpret such research are just unwilling to emphasize the complexity, interactivity, and flexibility that has been found. For example, consider an often referenced study of rats by Roger Gorski which showed that if you cut off a male rats testes at birth they acted like female rats in presenting themselves to be mounted unless they were given rat testosterone within the first five days of life.xiv The surface analysis suggests physiological determinism. Though initially interpreted relative to homosexuality, Burr later interviewed Gorski who agreed that the rat experiment was a "model for transsexuality rather than homosexuality.xv However, follow-up research shows a more complex picture. First of all, if one destroys the portion of the rat brain affected by the lack of testosterone nothing changes in the rat's behavior. Secondly, the other rats, that is the rats that mounted the altered rats, were not altered. Are they to be theorized as homosexual or bisexual?

The key point of the Gorski rat studies for transgender concerns is that fetal, or early development, hormones could be relevant for the way one wants to present oneself sexually. In responding to such a theory as it applies to humans, two critical points should be made. First, human sexual activity is far more mediated than rat sexual activity. For example, humans share sexually even when the female is not in heat. More important, human sexual choices are mediated by symbols which means the choices are influenced by cultural realities. Even in the rat studies, the rats that mounted were apparently affected by behavioral signs. To discover that there are physiological referents for human sexuality should not be surprising. What is important to remember is that there is a world of difference between demonstrating a physiological base and demonstrating physiological determination, or strong effect.

Anne Fausto-Sterling provides an extended history of the decades-long traditions of research on the hormonal manipulation of rats and guinea pigs in attempts to support prenatal (or perinatal) theories of sexual development and choice of partner. She points out, for example, that most of the studies are about male sexual differentiation. Before the 1990s little or no consideration was given to female development. She further points out that unaltered rats and guinea pigs show a lot of variability in their sexual expression, such as mounting behavior by females. Perhaps most importantly, Fausto-Sterling points to some studies of sexual expression in rats which show powerful environmental effects that challenge the validity of traditional research models such as the famous Gorski rat studies. After Fausto-Sterling's counter-analyses there is little left of value from decades of rodent studies. Yes, you can alter rodent behavior by cutting off genitals, sewing in new genitals, or giving overriding hormone dosages, but this doesn't eliminate the relevance of experience. Rats raised in isolation are sexually incompetent, for example. Most of all, the research shows that rat sex is not so simple, not so clear-cut, even in radically controlled clinical circumstances.xvi The relevance of hormones to behavior is considered further in a following section of this chapter.

For ethical reasons, there are very few studies of genetically based fetal sexual development in people. June Reinisch has conducted several indirect studies. One example is a study of grown children of mothers who took progestin during pregnancy. It show only weak indications of effect in a methodically difficult research line.xvii Her theoretical summary is that early socialization may increase a physiologically based proclivity for cross-gender identity, but she has done no research on such theorized early socialization.xviii If Reinisch's reasoning is correct despite the weakness of her research base, we would have one more example of physiological influence without physiological determination.

Another line of reflection about fetal hormonal influences comes from reasoning about human intersexual conditions, a matter discussed in the next section. Human intersexual studies are relevant but they do not point to physiological determination of gender behavior. For example, if someone with XY chromosomes (genetically male) nonetheless grows a female body (physiologically female), does one wish to reason from the genetic or the physiological base? Furthermore, in recent decades in the United States and in many other nations, intersexual people are usually altered at birth to conform to an exterior image of being male or female that satisfies the culturally based desires of doctors, and sometimes of parents. This limits the opportunities for studies of surgically uninfluenced intersexuality. It is hard to reason even about the effects of surgical alteration without considering the effects of hidden physiological factors which might, or might not, be influenced by the varying surgeries. Furthermore, intersexual people are assigned to one or another sex and raised accordingly, so the effectiveness of child rearing and socialization still matters. David Carlisle adds the wrinkle that a key hormonal effect may occur just before birth in which a premature breakdown of the mother's placenta subjects a male fetus to maternal steroids.xix This constitutes a prenatal but not genetic hormone theory.

Reasoning about sexual orientation relies on a comparatively simple dependent variable (choice of sexual partner), whereas reasoning about gender orientation has dozens of dependent variables. Even if one were to assign a lot of weight to hormonal variability in fetal development for explaining the choice of sexual partners - which is not justified by a fair summary of the research - it would not tell us much about the rest of gender orientation.

Alike and Different


This section moves to a description of adult human bodies as a basis for reasoning about contributions of physiological factors to sexual and gender experience. Most human physiological characteristics are distributed in patterns best described by a bell-shaped curve. Think of the height distribution of people as an example. Some are very short, some very tall, and most are in the middle. Bell-shaped curves have a single average. They are continuous, meaning that there are some people with the characteristic of interest at all the points along the way. The finding that so many human characteristics have bell-shaped distributions has led to the development of a branch of probability statistics based on the mathematical properties of bell-shaped curves, also called normal curves.

However, some genes, or alleles of genes, produce an outcome that is off the charts. In terms of a total distribution of height, for example, it would be most accurate to say that most people can be reasonably described in terms of height by placing them within a bell-shaped curve distribution but that a few people should be distinctively described as dwarfs or giants because their growth pattern is so uncommon. Those who think of same-sex sexual orientation or cross-gender appearance presentations as highly unusual commonly look for a genetic or other physiological needle in the haystack to explain what seems to them the equivalent of dwarfism or giantism. This book argues that we can learn what we need to know from the haystack.

If two groups of people are compared on a single characteristic, such as height, the mid-point (average) is likely to be different between the groups. For example, in the early and middle decades of the 20th century in the United States, younger generations were taller than older generations. On average, 30-year-olds are taller than 60-year-olds. The distributions in height of 30-year-olds and 60-year-olds are both bell shaped. If the two bell-shaped curves are superimposed on each other, you see a two humped compound of bell shaped curves that largely overlap. For example, it would show that even though 30-year-olds are, on average, taller than 60-year-olds, some 60-year-olds are much taller than most 30-year-olds. Reducing the reporting of these overlapping curves to a difference in averages distracts attention from the rest of the information about the distribution. Small differences in averages may be statistically significant, but the larger truth is the overwhelming similarity of the distributions.

Many of the articles about differences between males and females are based on comparing differences in averages between overlapping normal curves. Males, on average, are taller than females. However, some females, without being giants, are taller than most males. If we only considered the difference in averages we would miss the importance of a great deal of overlap of height in male and female populations. On the other hand, there is enough difference that height comparisons are noticeable. The political implications derive from what we make of such differences. At the turn of the millennia in the United States, there is very little legal differentiation of adults based on height.

When people are discussing sex differences, they commonly refer to the distribution of primary sexual organs: penises, vaginas, and clitorises, ovaries and testes. In adult populations, the distribution of the primary sexual organs is U shaped, the opposite of a bell-shaped curve. Most people have either ovaries and vaginas or penises and testes, but not neither or both. But there is more overlap than most people think, as is discussed later in the next section on intersexuality.

How much does it matter that males have penises and testes, whereas females have vaginas, clitorises and ovaries? It is relevant for part of the range of options in sexual intercourse but not definitive for sexual satisfaction in all people. It is determinative for differences in the biological reproduction of children. The secondary sex difference of producing breast milk is important for feeding infants.xx The influences of testes and ovaries on human development are expressed through hormones. As we shall see in a following section, such hormonal influences are not as sharply differentiated as one might think on the basis of the U shaped distribution of testes and ovaries.

What is the relationship between primary and secondary sex characteristics? The common idea is that people with vaginas and ovaries will grow breasts, have higher voices, and lack heavy facial hair. People who have penises and testes are expected to have beards and lower voices. But it doesn't always happen this way. Some people have penises and high voices. Others have vaginas, breasts, and beards. If you compared the distribution of people defined as male and female for a characteristic such as weight of breast tissue, you would see a two-humped normal curve based on some overlap between males and females, since fat men commonly have more breast tissue than do thin women. Some of these conditions are associated with specific genetic-based development patterns discussed in the following section on intersexuality. The point I am making is that there is more overlap than people commonly realize.

One significant example of overlap is found in the tone and volume range of male and female voices. Many accomplished transgender people have taken advantage of this reality to train and exhibit convincing voices commonly associated with the sex they were not-assigned at birth. Much of the presumed difference has to do with learned habits of pitch and rhythm. Similarly, the legs of males and females look a lot alike when they are shaved and encased in pantyhose, and racial comparisons show that females (or males) in one racial group have bodies of the general shape associated with males (or females) of another racial group. Though it is common to think and perceive with reference to cultural stereotypes of gender, readers can quickly reflect and notice that, in the United States there are not many men or women who look like fashion models or movie stars.

If we continue to expand our consideration of the physiological characteristics that many assume to be different for males and females - such as musculature, distribution of body fat, athleticism, hair texture, and various brain capacities - the distributions show a great deal of overlap. Take this line of reasoning one more step and consider the distributions of predispositions that some people argue are different for males and females, such as aggression, tenderness, artistry, mechanical aptitude, and choice of sexual partner. If the concepts of sexual differences were to be expanded so far, then, given some degree of overlap for each category, one would have to conclude that trying to designate most people physiologically as either pure male or pure female is a bipolar misstatement of a complex fact. A far more accurate statement is that most people have some sex or sex-linked characteristics to degree that is more common in people defined as the other sex. The physiological base for each element of the culturally created images of masculine and feminine appearance and capacity is related to multiple factors that are influenced by a complex genetic base and physiological development. Very few women look like Barbie. Very few men look like Ken.

Some writers could look at this same picture and write that most people are male or female except for one or a few deviant characteristics. Such a conceptualization is an attempt to hold onto bipolar thinking as a basis for social standards. It would be more accurate to say that if one is using a broad definition of physiological sex, as is common in our culture, the majority of people are predominantly male or female. The same truth is expressed by the comment that most people are at least partly intersexual.

Intersexuality


In this book, the word intersexuality is a physiological term. I prefer intersexual to the older term hermaphrodite because hermaphrodite suggests a half-and-half balance between male and female, which is misleading for many intersexual people. Though the term hermaphrodite has a medical-sounding connotation, the term is derived from Greek mythology. Eros, better known by the Roman name Cupid, was the child of Hermes and Aphrodite and was commonly pictured as intersexual.xxi

Babies usually have a vagina with a clitoris and ovaries, and not a penis and testes, or vice versa. But some babies are not so simple. Some are born with both penises and vaginas, with testicles and ovaries. Some people are born with male sex organs on one side and female on the other. Some people develop the primary sex organs of one sex but one or more secondary sexual characteristics of the other sex, such as breasts or beards. Some people are born with underdeveloped, impaired, or nonfunctioning primary sex organs. Chromosomal males and females produce both testosterone and estrogen, and some genetic females have as high a testosterone level as males. Genetic females have clitorises, an analog to a penis, and some are large enough to draw surgical attention because many parents are more interested in their babies conforming to cultural standards than in growing up to have an orgasmic sex life.

Medical and gender values lead to changes of primary and secondary sex characteristics and to hormonal changes. Some people lose primary sex organs, for example, by hysterectomies, and are still counted as males or females. Many people, not just transgender people, have had surgeries or other treatments to change their bodies into greater conformity with male and female stereotypes. Infant sexual reassignment surgery is done without the consent of children to solve a cultural crisis for parents or physicians. Transsexual people have had their penises and vaginas radically altered through sexual reassignment surgery. Male eunuchs and women who have had their clitoris ritually removed are part of many cultures. Currently in the United States and some European nations, chemical castration is a legal punishment for some sex offenders. Estrogen is sometimes used to treat prostate cancer and heart disease. Some women choose to replace hormones lost by menopause to avoid menopausal changes. Hormones are provided to some transgender people who do not choose sexual reassignment surgery. The questions of whether people who have changed their primary and secondary sex characteristics or hormonal patterns are more or less male or female, more or less man or woman, are not answered by the details of the medical procedures but by other considerations, especially the cultural meanings given to the different additions and subtractions and whether the subjective identity of the individual in question is accorded weight and value.

Any summary of the amount of intersexuality in human beings can be misleading, because it depends on the definition of intersexuality that is used. If we consider all the physiological features that are sometimes portrayed as sex differentiated in the culture of the United States, then most people are probably at least partly intersexual. If we narrowly focus on intersexuality of the primary sexual organs, Anne Fausto-Sterling estimates that 1.7% of all newborns are intersexual, most commonly as a result of late-onset congenital adrenal hyperplasia (CAH). If CAH is untreated, it leads to masculinization of the genitals, either at birth or during puberty. Fausto-Sterling's reading of the literature also suggests to her that there is significant variability by race and perhaps an overall rising rate of intersexuality.xxii Sheila Kirk is a medical doctor with a long association with the International Foundation for Gender Education. Her reading of the literature finds worldwide studies of intersexuality at birth in the range of 0.5% to 2%. She further reports that the number of intersexual births is apparently decreasing to its genetic base as more mothers are taught to avoid taking gene-altering substances during pregnancy.xxiii Another expert, Bo Laurent, believes the number of intersexual births is less than 0.2%.xxiv Given definitional disagreements, and considering inconsistencies in patterns of data gathering, such variations in estimates should not be surprising.

To further illuminate the complexity of intersexuality, we might note that cryptorchidism is found in 3% of live male births in the United States.xxv Cryptorchidism is the lack of the descent of one or both of the testes into the scrotum. The "wandering testis may be found in several locations. Sometimes the testes spontaneously descend; by adulthood, only 0.75% of males have this condition. Cryptorchidism is thought to have several physiological effects. Should XY people with cryptorchidism be thought of as male or as intersexual? Assigning either label can be misleading.

How much is intersexuality a cause of transgender experience and expression? Since both the theorized cause and effect are complex phenomena, it will be difficult for anyone to answer that question in a comprehensive way. But we can start. The high rate of cryptorchidism offers some support for the theories that there may be hormone irregularities in the prenatal histories of a significant minority of XY fetuses. However, if one wishes to argue fetal causes of transsexual experience and expression, one would have to explain why there is apparently much more fetal intersexuality than there is adult transsexuality. The rate of cryptorchidism, only one kind of intersexuality, is thousands of times higher than the rate of clinically identified transsexuals. A similar argument could be made in terms of Klinefelter's Syndrome, which affects 0.2% of males in the United States. This condition is caused by the presence of an extra X chromosome and causes hypogonadism, or weak gonad activity which produces a body with some pronounced female characteristics, such as breast development.xxvi

Does intersexuality account for transgender experience and expression? Perhaps there is as much transgender experience as there is intersexuality. The numbers on both ends of such an hypothesis are too little known to justify such reasoning. Some, such as Sheila Kirk, believe that intersexuality does cause transgender experience, particularly if a theorized fetal hormonal intersexuality is included. If one takes this point of view, transgender experience and expression would be an expression of a both/and "brain gender. However, studies of intersexual people do not lead to simple conclusions about the relationship between known intersexual status and gender.xxvii The safest theoretical position to take is that some kinds of intersexuality may strongly influence gender identity, whereas other kinds of intersexuality, and variations within the normal range of hormones and other physiological factors, may create weaker urges toward transgender experience and expression. Such theorizing is qualified by just what kind of transgender experience is being considered, such as choice of sexual partner or interest in pursuing a non-traditional career. These considerations are developed further in the sections on hormones and brain anatomy. Given the weak research base on fetal hormones, after decades of attention, it is unreasonable to defend a strong theory of prenatal determinism. It is also important to remember that any physiological causal path is likely to be much mediated by the cultural meanings attached to any results by affected individuals and their audiences. For example, an athletic girl may find it much more fun to match her ability against boys than girls; this preference may have genetic causes - just not genetic causes related to any of the above discussion.

Some writers have responded to one or another aspect of intersexuality and proposed that some people should be considered a "third sex. To defend a third-sex assertion, a distinct characteristic not found in males or females would have to be shown. A more reasonable summary is that there is much more overlap than many people realize.

Questions About Hormones You Would Have Asked If You'd Known the Answers Would Be So Interesting


Hormones affect our feelings in general and sexual arousal in particular, so it isn't surprising that hormone studies have attracted substantial attention. Furthermore, many transgender people seek out hormone therapy as part of their gender exploration. Hormone research points to a much more complex reality than is commonly understood. Susan Rako, in The Hormones of Desire: The Truth about Sexuality, Menopause, and Testosterone,xxviii has recently summarized many studies showing that the level of testosterone in women is critical to sexual desire and argues that hormone replacement treatment in response to menopause should include testosterone as well as estrogen and progesterone.

Testosterone and estrogen are structurally similar hormones, manufactured by the body from cholesterol and thus called steroid hormones. Both testes and ovaries create both hormones, although in different amounts. One hormone can change into the other. Although both hormones are usually called sex hormones they are actually growth hormones that produce effects on many parts of the body. These two hormones are only part of a class of related hormones that are similar in structure and affect each other in complex ways. Some of the hormonal sequences affecting body growth and processes are quite complicated and involve many organs other than the testes and ovaries.xxix Among other things, these facts mean that the genetic base for this complex reality is also complex and that any particular gene, such as Hamer's theorized gay gene, is likely to play only one small part in creating the complex whole.

The range in concentrations of testosterone and estrogen and related steroid hormones in the bloodstream that is considered normal within the male or female category is quite large. Depending on which hormone is being considered within a sexual category, one person can have a seven times higher concentration than another person and both can be counted as normal by current clinical standards. For example, some females in the range defined as normal have three and a half times as much testosterone as other females in that range. The same is true for males.xxx This means that there could be hormonal factors affecting transgender experience that are within the range of normality rather than abnormality, a reality which points to the relevance of haystack rather than needle theories in considering genetic and other physiological grounding of transgender experience and expression.

Rako reports on the work of James Dabbs, who studied the distribution and activity of testosterone in males. In a study of 92 men in 8 occupations or unemployed, Dabbs found a higher level of testosterone in professional football players and a lower level in ministers. He also found a higher level in trial lawyers than other lawyers.xxxi If testosterone levels have some effect on the choice of professions, it is reasonable to assume that testosterone levels may affect other social choices, including gender experience and expression. Dabbs also found that testosterone levels vary in response to time of day, successfulness in social encounters, and sexual activity. It is also important to remember that there are plenty of women who are great trial lawyers, even though they have testosterone levels that are a small fraction of male levels. The themes of complexity, interactiveness, and flexibility are as important for theories of general gender liberation as they are for this book's focus on transgender concerns.

Although testosterone levels are much lower in most females than in most males, it is still very important for females. In addition to its importance for the sensitivity and vitality of genital tissues and the nipples, testosterone is important for muscles, bones, skin, hair, and many other body processes. Rako reports that Samuel Yen, in Reproductive Endocrinology, writes, "Testosterone and other androgens have some biologic activity on virtually every tissue in the body.xxxii Females generate testosterone in their ovaries, and most of it is converted to estrogen before entering the bloodstream. About three-quarters of the testosterone available in the blood of females is generated by the adrenal gland and in other diverse locations. The effects of testosterone are also dependent upon the work of receptor elements in cells and mediating chemical processes. The fact that testosterone is generated and used in so many locations, and is significant to so many processes in females, suggests that the genetics of testosterone production and use is enormously complex.

If testosterone and other steroid hormones make causal contributions to psychological identity and social behavior, the above findings suggest that it is most reasonable to assert that such contributions are mediated by many physiological factors and that some of the physiological results are in turn intermediary factors for psychological and social causes. For example, a researcher might conduct a study which showed a correlation between a particular level of a hormone and an emotional capacity for nurturance. This would be interesting, but many other things would have to be considered before a theory of causation would have any weight. Might the emotional activity be causing the hormone level? What is the distribution of this hormone at different levels in the population? What counts as nurturing behavior? How does culture distribute opportunities for different kinds of nurturance between men and women? Dabbs made a contribution to this kind of research and Dabbs, and then Rako, that the causal factors are complex, multi-directional and interactive. Doing this kind of research in the analytic tradition requires complex inter-disciplinary theorization and testing. However, viewed in a synthetic context, which emphasizes the release of potential in contrast to seeking out fractions of causative influence in shifting and complex circumstances, it is easy to honor complexity, interactiveness and flexibility as sources of variability in human populations. It is easy to honor psychological and social causal factors without positing them as contradictory to, or overriding of, physiological factors. Such honoring of all scientific contributions is the path to escaping physiological, psychological, or sociological essentialism, to escaping disciplinary hubris, without dismissing useful contributions from each source. It is one thing to try to prove the theory that prenatal hormonal conditions cause transgender experience and expression and quite another to investigate how prenatal and other hormone conditions might contribute to greater or lesser degrees to one or another aspects of transgender experience and expression in interaction with psychological and social factors, and then to consider the relevance of how people respond to their understandings of the spiritual factors discussed in the last chapter. It doesn't matter that any single scientist is likely to check out long before all such complexities are investigated. Each can make a contribution and then theorists, and interdisciplinary theorists, can each have their turns.

During most of childhood, male and female children have similar levels of steroid hormones. Then a surge of testosterone initiates puberty in both males and females. In old age, men and women move back toward having similar levels of estrogen, while most men continue to have higher levels of testosterone. These usual variabilities in hormonal development and change lead to questions that have been given little attention. What does it mean that children become gender differentiated at a time when they have similar hormone levels? Why is our culture more accepting of older women taking sex hormones to reduce or delay the natural condition of menopause, of men taking drugs to improve erections, and much less accepting of transgender and transsexual people taking hormones to achieve a physiological state that they desire? The answers are not to be found in additional endocrinological studies.

Perhaps the most intensely studied physiological cause of adult sexual behavior is comparative levels of testosterone in gay and straight males. Heino Meyer-Bahlburg published a summary of 27 such studies.xxxiii He found that 20 studies showed no difference in hormone levels between gay and straight men. In three methodologically troubled studies, gay men had lower testosterone levels; in two, their testosterone levels were higher; and in one, bisexual men had higher levels than gay or straight men. Finally, a study of male identical twins, in which one twin was gay and one was straight, found that the twins had similar levels of testosterone. This summary pretty much ended the search for such differences.

In the context of this review it should be pointed out that the studies reviewed by Meyer-Bahlburg concerned choice of sexual partner, not the degree of expressed masculinity or femininity. There is a lot of difference between how one chooses to present oneself for social and sexual encounters and what one looks for in another person. It is quite reasonable that hormones, or other physiological processes, might affect one's sense of identity or preferred activity without affecting the choice of sexual partner. On the other hand, the Meyer-Bahlburg summary suggests that powerful, genetically based hormonal factors are not determinative, or even discernible, in their effect on adult sexual behavior. Two studies of transsexuals showed that "the hormone levels were found to be within the normal range for the individuals' original gender... suggesting that transsexualism does not result from a hormonal imbalance.xxxiv Perhaps the work by Dabbs, or others, will become more compelling. Until that time, the fairest summary of the causal effects of hormonal level on transgender experience and expression is that it has not been shown to be a factor.

If the above summary has not been sufficiently confusing, consider a later study of rat brains by Roger Gorski: "It turns out that much of the work of masculinizing the brain is not actually done by testosterone itself, but instead is carried out by estrogen, which is produced from testosterone by the brain.xxxv

Readers looking for a good source of information on the role of hormones in intentional physiological change in transgender people may go to www.savina.com/confluence/hormone/.

Our Amazing Brains


Some look for a hidden needle of gender variance in the haystack of the brain because the brain is the physiological base for subjective awareness. Maybe there is a brain factor that occurs only in males that creates masculine subjectivity and/or a distinct factor for females that creates feminine subjectivity. Even before commencing the search for such a factor, one would have to define such a masculine or feminine subjectivity and show that it existed across cultures. Quite a challenge.

Those who do brain research with concerns for sex and gender usually merely assume that there is a difference in male and female subjectivity and that any difference they might find in brain structures is the cause. Even though such thinking is incredibly sloppy, it hasn't slowed down research efforts to find differences between the brains of males and females or differences between the brains of straight people and some sexual minority.

Consider the search for a brain difference that influences the choice of sexual partners. It is one thing to theorize differences between the brains of gay men, lesbians, and straight people and another to demonstrate such a difference. A popular theory at the time of writing is that during the fetal development of some males the MIH hormone defeminizes the primary sex organs but not the brain. Such males, the theory holds, would have masculinized brains because of the effects of testosterone, but not defeminized brains because of the lack of MIH effect. This theoretical approach has not projected specific brain effects that might be observed. Instead, brain anatomists with an interest in this area continue to look for any brain differences, in the hope that such differences will fit with such a theory. In effect, we have a "theory that cannot be disproved; and a theory that cannot be disproved is not a scientific theory, only speculation.

The research on differences between male and female brains that has drawn the most attention is a possible difference in the corpus callosum, a large brain organ that mediates between the higher brain centers and other parts of the brain. Laura Allen is the best known defender of the theory that there are differences between males and females in the corpus callosum.xxxvi However, Anne Fausto-Sterling points out that 23 followup studies to Allen's research did not find the proposed difference.xxxvii Chandler Burr reports an interview with Laura Allen where she points out, presumably in her defense, that she correctly identified the sex of two-thirds of a sample of corpora callosa in a blind test. Even if her theory had not been sunk by the lack of replication, it seems fair to say that if such a highly trained anatomist can find a male versus female difference only two-thirds of the time, her research can be disregarded. Two other eminent brain anatomists sum up the issue of difference in size of the corpus callosum between males and females as measurable, but either as less than the variation in size within populations of males or females, or as largely irrelevant and insignificant.xxxviii Some experts think that the corpora callosa of males are generally bigger than the corpora callosa of females but that the corpora callosa of females are relatively bigger in comparison to body weight.xxxix Overall, this extended research is a classic example of the general point made earlier about the misdirection of emphasizing differences in averages in the distributions of male and female physiological characteristics when the larger truth is significant overlap.

In a later review of the extensive research on proposed male and female differences in the corpus callosum, Fausto-Sterling attends in detail to numerous methodological problems in measuring the corpus callosum. She reviews hundreds of different kinds of measures looking for difference. Little is known about the functioning of a living three-dimensional corpus callosum, and almost all the research has sliced and diced the organ into various sections without asserting a theoretical reason for the relevance of a particular measure. Even before getting to the issue of some mis-constructed statistical work, Fausto-Sterling makes the point that the efforts to find differences have been so unfruitful that more recent research has tried to solve the problems of assessing differences by turning the judgment over to panels of objective observers and then comparing their levels of agreement. Such anatomical research is a very long distance from looking at a corpus callosums, pointing to a difference, and saying, "There it is. Fausto-Sterling asserts that after a century of looking for a difference between males and females in the corpus callosum without any luck it is time to point out that they are similar and move on. Science is not served well when culturally driven theories blind researchers to the obvious summary of observations. However, even after several scientists have summarized the overwhelming similarity the drive to find a difference continues.xl

One current line of research to find differences between the brains of gay, lesbian, and straight people revolves around microscopic somethings called INAHs. In contrast to the big corpora callosa, INAHs are so tiny that some researchers doubt whether some INAHs actually exist.xli The fairest summary of this research is that it is inconclusive and much challenged. For one thing, even if it were shown that there was something about INAHs that differentiated straight people from gays or lesbians, no one has figured out what INAHs might do. There are a lot of things in the body that don't do much, including most genes.xlii

The failure to find important brain differences could lead us to discount the importance of brain anatomy as a base for gender development. This is like saying "Because we couldn't find the needle, we can forget about the haystack.

Those who have wanted to show a physiological cause of sexual orientation, or of differences between men and women, have been eager not only to show distinctiveness but also to argue that such differences are unchangeable. But the brain is anything but hard-wired in its development. There are about 10 billion neurones in the cerebral cortex, the physiological base for thinking, and the possibilities for their linkage are almost limitless. Quoting Chandler Burr, "Before birth and the final fixing of the brain structure, the neurones roam freely from place to place like nomads... Quoting Burr further on the connections between neurones, "the bridges, like the dense streets of a medieval city, develop randomly this way and that into a network between cells that happen to meet during their own independent drifting in a sea of neurones, haphazardly growing into the stable circuitry of a mature brain.xliii Such a picture of brain development suggests that the physiological base in the brain for the activity of the mind is highly flexible. We know that the capacity to think and make decisions has some kind of physiological base in the cerebral cortex. Finding such flexibility and complexity, it is not hard to believe that we can think thoughts that are new to us, create sentences we have never heard before, and work out creative responses to gender choices. Anyone who wants to argue some version of a theory of sexual orientation as hard-wired will have to argue that sexual response and gender choices are not mediated by the higher functions of the brain - that the cerebral cortex is irrelevant. Such argumentation would also have to overcome direct evidence based on positron emission tomography of functioning adult brains that shows numerous parts of the cerebral cortex are involved in sexual arousal.xliv

The issues mentioned in this section have not deterred those with deterministic theories. A good example is Joseph LeDoux's 1996 book, The Emotional Brain: The Mysterious Underpinnings of Emotional Life. He writes, "The conscious feelings that we know ...our emotions by are ...detours in the scientific study of emotions. Feelings of fear, for example, occur as part of the overall reactions to danger and are no more or less central to the reaction than the behavioral and physiological responses that also occur, such as trembling, running away, sweating, and heart palpitations.xlv He later argues that both cognition and emotion are primarily unconscious processes and that only the outcomes of such processes become conscious.

The problems of LeDoux's book are typical of those of any researcher of human behavior whose work is limited to an analytic standpoint. LeDoux tells his readers that most of his work is dependent on research on rat brains. This method has two core problems. The first is that rat brains have some similarities to and some big differences from human brains. Humans have a massive cerebral cortex, for example. LeDoux responds to this problem by asserting that for animals with brains and backbones, "the systems underlying fearful, sexual, or feeding behaviors - is pretty similar across species.xlvi What he means is that the physiological structures in the brain that are the base for these emotional patterns have some similarities in many species. In effect, LeDoux is arguing that you don't have to pay attention to human differences because many species are similar. He has done important work in identifying specific brain systems that are part of the physiological basis for specific emotions. Nonetheless, as with Hamer's work in genetics, LeDoux has not considered the unobservable potentials of such structures as they interact in more complex wholes and generate phenomena which can only be observed outside of his discipline. LeDoux understands that mental activities, like discipline, can constrain emotions and the effects of emotions on choice and behavior. He admits that higher brain functions affect emotions such as fear. But he still chooses to write as if identifying a physiological base for fear means that he has explained fear.

LeDoux writes, "If we do not need conscious feelings to explain what we would call emotional behavior in some animals, then we do not need them to explain the same behavior in humans.xlvii Since human have a distinctive and highly developed cerebral cortex to do such mediation, it is illogical to assert that human emotions are not mediated by consciousness because nonhuman animals lack the mediating structures of humans. Neither is it clear that fear is unmediated in nonhuman animals. Just because LeDoux can't talk to a horse about being afraid doesn't mean that horses lack any conscious mediation. Much animal training demonstrates the mediation of fear in nonhuman animals. Put differently, learning affects how human and nonhuman animals respond to various stimuli. The capacity for fearful response to a particular sensory signal does not mean that such a sensory signal will always produce fear as a conscious emotion or the accompanying signals of sweating and the like.

A possible distinction between male, female, and transsexual brains has been reported by Josie Glausiusz, based on a limited study of human brains by a team of Netherlands researchers led by Dick Swaab. They report distinct differences between men and women in the size of a tiny brain region known as the BSTc.xlviii Prior study of rat brains suggests that this brain component is critical to sexual activity. Swaab's team compared six brains of male-to-female (M2F) transsexuals in this study and found the BSTc regions were roughly the same size as those found in the brains of females. Before such a study could be evaluated properly, we would need to know the range of variation of BSTcs in male and female brains and whether any difference is a result or a cause of variations in sexual activity. That would include defining a specific human sexual activity, showing that variations in BSTcs were correlated with the specific sexual activity, showing that men and women differed in this sexual activity, and then showing that M2F transsexuals behaved more like women than men in such a sexual activity. This is the kind of study, however small, that keeps raising hope that one or another needle will be found. But, as with other proposed needles, this initial finding is unlikely to be replicated.

So far, the picture drawn by this chapter shows that after substantial effort, no needle of explanation has been found and defended in the physiological haystack of complexity, flexibility, and interactivity. Instead of arguing for or against direct physiological causes of transgender experience and expression, it might be more helpful to consider physiological circumstances that could support or encourage transgender experience and expression. For example, consider a person with Klinefelter's Syndrome, mentioned previously, a condition that results in male genitals and fully developed female breasts. The issue for people with this condition is not so much gender transition as choice of gender when one's body provides mixed signs of cultural significance.

What might be explained with a deterministic physiological theory of gender formation? Are we trying to explain nurturance in men, why women are now commonly wearing pants, or whether there is a gene for attraction to lipstick? Most of those doing research related to transgender experience and expression that I have read would say they want to explain the development of subjective awareness or orientation that, in turn, affects the defining and valuing of transgender experience that, in turn, affects transgender expression.

It may sound simple to name, but transgender related subjectivity is not simple. For example. is muscular strength important to one's subjective sense of gender identity? Perhaps it is for some people. We have seen that the genetic and physiological basis for the development of muscular strength is complex. We have argued that such factors as muscular strength can only be one factor among many in the development of gender identity. One changing cultural factor is that girls are now more often encouraged to become athletes, to think of themselves as strong. The subjective implications of strength for the development of gender identity has changed without any change in genetics or physiology. And whatever the status of such research, those with an eye to the politics of science might also want to remember that slavery wasn't ended by studying slaves.

In reasoning about transgender experience and expression some may point out that there are transgender people who have the kind of bodies that make passing as the other sex relatively easy. On the other hand, there are people (like me) who are challenged to make a respectful feminine presentation. Some clinicians have had the presumption to deny transsexual surgery to people who look like me because we don't meet their stereotypes of femininity. Such denial isn't grounded in a surgeon's expertise on the physiology of health. Feminists properly argue that such decisions reinforce gender stereotypes. The third chapter examines relevant psychological issues and the seventh chapter deals with the development of a clinical movement which has taken advantage of the ambiguity in this area to seize this society's social control of gender conformity.

If those arguing for physiological deterministic causes want to escape from arguing symbolic mediation as an intermediate factor, they must assert some hidden physiological factor. If such a factor exists, this chapter has shown it isn't likely a matter of genetics, hormones, or brain anatomy. It is one thing to talk about relevant physiological factors and predispositions and quite another to argue for a strong specific factor (needle) that explains everything. It seems to me that the contemporary challenge for any physiologists interested in transgender-related research is to help gain more understanding of the complexity, interactivity, and flexibility of physiological factors as they support the possibility of transgender experience and expression.

Darwinism One More Time


A different kind of physiological determinism is the theory that current cultural standards concerning sexual orientation or gender expression are merely the expression of evolutionary forces in a human context. Such theories name some evolutionary "interest that has led to our current cultural images and social roles. These theories proceed as if there were some kind of independent evolutionary actor, an idea we will revisit in the section on natural theology in the last chapter. The concept of survival of the fittest easily attaches to an idea of some hidden hand giving direction to human evolution. Such a theology, in turn, gives comfort to those who defend their dominance by arguing it merely proves they are the best fit to dominate.

Neo-Darwinist rationalization about human beings has a long and ugly history in nineteenth and twentieth century thought in the United States. This school of thought has been used mainly by conservatives and reactionaries to avoid social responsibility for the conditions of those who are oppressed, as in slavery, patriarchy and, most recently, those receiving welfare benefits. Richard Hofstadter, after extendedly pointing out that "There was nothing in Darwinism that inevitably made it an apology for competition and force, accounts for the recurrent popularity of NeoDarwinism in the United States as follows: "The answer is that American society saw its own image in the tooth-and-claw version of natural selection, and that its dominant groups were therefore able to dramatize this vision of competition as a good thing in itself. Ruthless business rivalry and unprincipled politics seemed to be justified by the survival philosophy. As long as the dream of personal conquest and individual assertion motivated the middle class, this philosophy seemed tenable, and its critics remained a minority.xlix

Whatever one thinks of neo-Darwinist ideology, it is fair to point out that natural selection is an important part of biological reasoning. But evolution also turns out to be complex and interactive.

Contemporary genetics teaches that the process of natural selection does not operate in a simplistic, straight-line fashion. For example, Chandler Burr points out with implicit humor that "maze brightness in rats is genetic and can be bred for.l But, it turns out, this enhanced capacity to run a maze is based not on increased intelligence but on a semiblindness that decreases distractions. Conclusion that could be drawn from this study are that rats are smarter than maze studies can measure, and that rats with the intelligence to seek for alternatives to stupid maze running were too much for the experimenters to cope with.

One way to illustrate the complexity of natural selection as a biological process is to point out that there are inherited, genetic-based traits that are lethal when expressed. They are passed along because the potential lethal expression is linked to something that is positive for natural selection. For example, the gene which contributes to the creation of sickle cells strengthens the body for resisting malaria but also harms the body by creating anemia when it is inherited from both parents. If genes with sometimes lethal effects can be part of natural selection, then neutral traits, or traits that are positive in indirect ways for a human population, can certainly be a part of natural selection and evolution.

One part of getting our evolutionary facts in order begins with realizing that homosexual and transgender people are the biological parents of many children. This doesn't make sense to the stereotypes of the straight world, but it is nonetheless true. Not only do homosexual and transgender people biologically create children, they also are active parents to children, their own and those they adopt. Richard Green did a study of such children and found they were as likely as the children of straight parents to grow up straight.li Furthermore, if most writers about transgender issues are correct in their commonly held opinion that male cross-dressers are primarily heterosexual and are typically married and parents, the debate about input to the gene pool is irrelevant. Myself, I'm the biological parent of three children and am currently helping to raise two more in a blended family.

The biology of natural selection has to do with the survival and transmission of the gene pool and not of individuals. That is, if an individual is a contributing member of a successful society, then that individual is contributing to the survival of the gene pool of that society. In our current society, many believe that excess population is more of a threat than insufficient population. If that is true, those who contribute to societal success without adding to the "dependency ratio by creating children might be theorized to be strengthening the gene pool of society. So, even if it were true that homosexual or transgender people have fewer children than average, it would not necessarily hurt the survival of the gene pool of a society, which includes the gene pool basis for gay, lesbian, bisexual, and transgender people in that society.

If we consider the features that are most physiologically distinctive about human beings - the capacities for intellectual reflection, artistic creativity, and the creation of complex social and cultural relationships - it may well be that human freedom from a hard-wired sexuality, expressed in many interesting ways, is a key component of these "highest human capacities. For example, one distinctive human capacity is the ability to attach passionate commitment to such symbols as flags and crosses and curves. Given the complexity of our culture and society, it might well be that the genes that most contribute to intellectual and emotional complexity and flexibility are the genes that are most valuable for strengthening the genetic pool as a base for future evolution. If any transgender genes are ever discovered, they might be just such valuable genes.

The core logical problem with all kinds of political or spiritual Darwinism is using the concept of natural selection metaphorically rather than biologically, then arguing physiological determinism as if that proved the metaphor. Laurette Liesen provides one example of such thinking when she asserts that females are usually more interested in personal bonds, whereas males are more interested in abstract thinking; that this difference is genetically based and derives from an evolutionary advantage; and that this difference accounts for the gender gap in contemporary electoral politics.lii The previous section on genetics has shown that there is no genetic basis for Liesen's assertion, and a section in Chapter Three on non-clinical psychological research shows that there is no scientific psychological basis for asserting that males are less interested in personal bonds than females. Liesen, as is typical for neo-Darwinists, offers no direct genetic evidence to support her theory. She merely presents her theory, acts as if must be obvious, and then asserts that such a basic difference must be genetic.

All the other neo-Darwinist arguments I have encountered theorize some evolutionary "advantage or "interest and are equally grounded in imagination rather than in data. I offered an equally projective theory when I wrote above about the possible advantages of transgender genetic contribution. We are all free to theorize. My own dipping into neo-Darwinist theory was to show that two can play such games. The larger point is that neo-Darwinist thinking is not grounded in science.

The version of neo-Darwinism in recent years that has gained the most prestige is the sociobiology of Edward Wilson.liii Wilson argues that males are dominant in all known societies and that such universality represents a genetic advantage of males over females. His point about males dominating all known societies is commonly supported in anthropological textbooks.liv Anne Fausto-Sterling counters with three questions. Is it universal? Does it mean the same thing in all cultures? Even if it is universal, is genetics the cause? Her conclusion is that Wilson's sociobiology is a political attack on women's liberation that boils down to the assertion that "things aren't so bad the way they are...because it's natural.lv

Ernst Mayr, a leader in the development of evolutionary biology, argues an alternative understanding of the implication of emphasizing a population based, rather an individual based, understanding of biological evolution. "The survival and prosperity of a social group depends to a large extent on the harmonious cooperation of the members of the group, and this behavior must be based on altruism.lvi How is one to choose between these alternatives readings of "sociobiology when both authors are building on similar readings of the same data? The first thing to remember is that such post-hoc analysis is more akin to history as a discipline than to experimental biology. In reasoning about transgender experience and expression, the important thing to remember is that we are trying to understand the evolution of human beings who demonstrate a great variety of gender expressions rather than trying to explain the selective advantage of a specific physiological trait such as being able to make a tube with one's tongue.

Suppose we were to agree with Wilson that in all societies men are more aggressive and fickle than women, and that the difference is genetically based - two suppositions that I think are unjustified. There would still be two hurdles to pass before assigning weight to such a theory.

The first is that although factors such as size or testosterone levels may make it possible for males to get away with aggressiveness and fickleness in social interaction, these behaviors do not show that there is some irresistible, physiologically based urge to be aggressive and fickle. Furthermore, even if such an urge were supposed, Freud, Locke, and others have argued that it is the overcoming of such negative animal nature that makes society possible. I do not agree with Freud, Locke, et al, because I do not think the suppositions are justified. But if I did, I would use Wilson's valuable articulation of the importance of thinking of genetics in terms of populations, his emphasis on the survival and enhancement of the gene pool rather than the survival of individuals, to argue that cooperation and trustworthy social relationships are sociocultural advantages that undercut his simplistic sociobiology.

The second point has to do with whether anyone is currently arguing that aggression and fickleness are a good thing, or a social advantage, or a desirable psychological trait. Most of the sociobiologists back off to a position like "Well maybe these are not desirable characteristics, but that is the way things are, and we have to learn to live with them. But "the way things are is an assertion of fact that doesn't fit very well with the reality in the contemporary United States that churches, schools, and other major institutions support standards of cooperation rather than aggression, support stability rather than fickleness. Although it is important not to give away the factual picture to the neo-Darwinists, it is also important to remember that ubiquity doesn't equal desirability. We have the genetic capacity as males, females, and intersexuals to grow into men, women, and transgender people who can choose how we respond to any urges to aggression or fickleness, whatever their source. We can choose greater personal happiness and greater social benefit instead of sliding down the well-worn slopes of patriarchy, denial, hostility, irresponsibility and war.

In contrast to any who would turn to sociobiology for political and spiritual arguments to oppress transgender people, William Dragoin has advanced a sociobiological theory that links transgender and shamanistic behavior. Dragoin appeals to a fetal hormone theory of brain development as a source of shamanistic talent and argues that shamanistic talent was so valuable to early homo sapiens that it gave an evolutionary advantage to transgender people, primarily through the prestige conferred on close relatives of transgender shamans.lvii Although I find several problems in Dragoin's reasoning, it is nonetheless an excellent example of theorizing that meets sociobiological standards and shows that sociobiological thought can be used to argue for a normal rather than an abnormal understanding of transgender experience and expression.

Traits and Choices


One of the most common confusions in reasoning from genetics to subjective feelings or human behavior is caught up in the word trait. Geneticists commonly use the word to refer to a physiological structure, such as the shape or color of an eye. They also refer to certain behaviors as traits. For example, the capacity to make a tube with one's tongue is genetically based. Some people can and some can't. Part of the confusion in the word trait is the difference between capacity and expression. The expression of a genetic capacity for a behavior named as a trait is thought of as being without choice, just as the color of one's eyes is not a matter of choice. Yet those who can make a tube with their tongue can choose whether they want to do it or not. Mostly they don't, since it gets in the way of talking, eating, and other mouth activities.

Handedness is an interesting trait that is assumed, but not yet demonstrated, to have a genetic basis. Handedness studies show that most people are right-handed, some are left-handed, and very few are truly ambidextrous. This would graph as a J shaped curve: high on one end, lower on the other end, with a trough between. Chandler Burr is interested in handedness because he thinks the observed distribution of handedness is similar in shape to the distribution of sexual orientation.

The general summary of handedness studies is misleading in an important way when we consider how people use their hands in everyday life. Without denying for a minute the scientific accuracy of the handedness studies as summarized above, it is critical to understand what is being said and what isn't. I'm right handed, but I am typing this paper with both hands. I'm hitting about as many key strokes with my left hand as with my right. The handedness studies were not interested in the fact that most people use two hands for two-handed tasks. A more accurate generalization is that for tasks that are commonly one-handed, most people use their right hand, some use their left hand, and a few are truly ambidextrous.

But the improved generalization about handedness is misleading in another important way. I usually hammer nails using my right hand to hold the hammer. But there are some carpentry situations where I hold the hammer with my left hand to get a better angle. Furthermore, when my right arm gets tired, I switch over and hold the hammer in my left hand. Furthermore, in some tasks, like roofing, I find myself relieving boredom by practicing left-handed hammering. And, when I'm hammering a stake into the ground, I may use one or both hands. So a further improved generalization about the human trait of handedness is that for tasks that are commonly one-handed, people typically use a preferred hand but adjust to fit various situations or in pursuit of different purposes.

But even this further improved generalization about handedness is misleading in an important way. If I were to lose my right hand in an accident, I would use my left hand for a lot of tasks I currently prefer to do with my right hand. I would expect to gain strength and skill. Leon Love, father of my best friend in high school, lost his right hand to a fuller's earth grinding machine. He developed so much drafting skill with his left hand that he earned his living as a draftsman for most of his life. Losing his right hand was part of the causal chain to gaining a better-paying job with far better working conditions. What does it mean to say that Leon was right-handed? It means that he preferred to use his right hand when he had the option of using either hand. It also means that he had the genetically generated physiological base for doing left-handed work with a high degree of skill. Like right-handed hitters in baseball who choose to learn to switch hit, the choice of which hand to use may be genetically influenced while still allowing many other possibilities.

There is one more significant correction to the apparently simple generalization about handedness. Some people are apparently more able than others to share tasks, or switch tasks, between hands. Chandler Burr reports a study by Rob Collins of pawedness in mice. Collins found that 50% of mice preferred their right paws and 50% preferred their left paws, and that the trait was very stable when the task of getting a food pellet was equally accessible to either paw. But, when Collins made it hard to get the pellet with either the right paw or the left, most of the mice switched paws. But some mice couldn't, or at least didn't, switch paws.lviii This illustrates the importance of the issue of the strength of the trait. It is honest to report that mice preferred either their right or their left paw. It is equally honest to report that the overwhelming majority of mice were willing to use either paw to get a desired result and that those in the small minority might have starved to death if they couldn't adjust and if the experiment was their only opportunity to eat.

With all these qualifications to the generalization based on handedness studies as classic studies of genetically based traits, if one were to support a metaphor based theory that the distribution of handedness in human populations is like the distribution of sexual orientation, one would be arguing in support of complexity and multiple understandings of sexual orientation rather than a sharp distinction with little overlap. Furthermore, relative to the previous section on neo-Darwinism, it is interesting to note that the flexibility that comes from being able to use two hands in similar ways, in complementary ways, and in coordinated ways is an important evolutionary advantage.

The word trait, as used in genetics research, isn't inaccurate or misleading. But we must remember that what the word trait means in the context of genetics - in which there is a strong interest in differentiation as part of the research trail for finding genetic locations - can be quite different from the discussion of a trait in psychological or social terms. The difference is that when the reference discipline is psychology or sociology, physiological factors are only one source of causation. When physiological factors are functioning in typical ways, they may be the least interesting factor to be considered. Whether one chooses Japanese or Algonquin as a second language - a choice which might have significant psychological, social and cultural consequences for an individual - is not likely to turn on the physiological base for language, even though such a base is going to be fully involved in responding to the choice.

The gay and lesbian community was quick to celebrate the decision by the American Psychiatric Association in 1973 that homosexuality is not a disease. However, as Chandler Burr exemplifies, much of the gay and lesbian community is eager to hold onto the concept that homosexuality cannot be changed. Burr names the ineffectiveness of all the things done by psychiatrists and psychologists to homosexuals to get them to change as part of his evidence against the theory that homosexuals have a choice about their sexual orientation. But, as we shall see in Chapter Four, survey research suggests that, while it may be true that some homosexuals cannot be changed by clinical intervention, this doesn't mean they don't change on their own as part of their everyday lives. Both truths fit together nicely if one considers how homosexuals were selected for clinical intervention. They were typically forced into clinical settings by homophobic pressures and treatment amounted to attempts to force change. Considering what we learned from a review of genetics and physiology, it is quite plausible that physiological factors are significant for some, but not all, people with homosexual experience. That would indeed fit a J shaped curve but the findings I summarized argue against any genetic determinism.

To point out that the expression of genetically based traits contains choice does not mean that there are no physiological influences on psychological or social traits. Although psychological traits are not wholly determined by physiological considerations, personal choices are not unaffected by physiological considerations. I might like to sing, might want to make my living as a singer, but, if I don't have a good set of "pipes, I'm not going to get very far socially or economically and may be frustrated emotionally. On the other hand, some singers are such great performers that they make a living with quite limited voices.

The point is that choices by human beings in real social settings may be affected a lot or very little by physiological factors. Even when a strong physiological urge is served, such as hunger, it may be done in different ways. I may prepare Chinese food for dinner, but I might go out to my favorite Salvadoran restaurant. If a person chooses a partner for erotic sexual sharing, or presents an image in hopes of being chosen, a complex of physiological, psychological, social, cultural and spiritual factors are relevant. Just because some urges feel powerful, just because some choices are commonly made with little reflection, doesn't mean that the dominant cause is physiological. I have a powerful urge to communicate and I use English without reflection.

What Our Bodies Contribute to Transgender Experience


There has been very little direct physiological study of people who have transgender experience and engage in transgender expression. Physiological reasoning about transgender experience and expression usually theorizes some simple or distinct physiological cause, skips over all the intervening variables, and oversimplifies or misunderstands the transgender experience or expressions to be explained.

In this chapter on physiology I have emphasized complexity. Many other writers have looked for, or just theorized, a simple physiological irregularity to explain transgender experience and expression. I've suggested that the most reasonable summary of the relevant research is that physiological factors are not likely to be strongly determinative in the explanation of everyday transgender experience and expression. Any simple theory is unlikely to match the complex physiological factors that may be relevant, not to mention the additional complexities of psychological and social factors.

We are each born with whatever mix of physiological characteristics arises from the interaction of our genetic materials and the uterine environment. In this sense each of us is natural. Intersexual people are as much the outcome of natural processes as other people. Instead of beginning by looking for the unusual, the first task of physiologists is to correctly image the usual distributions of various physiological characteristics. If the various kinds of physiological scientists who are interested in issues of sex and gender were to begin by appreciating the complexity, interactiveness, and flexibility indicated by all the forgotten studies which didn't find a simple deterministic cause, perhaps they might begin to focus on the mechanisms by which physiology supports highly diverse sexual and gender realities. At a minimum, such a focus would undercut the simplistic and unsupported physiological reasoning used by some psychiatrists and psychologists who impose sickness theories on transgender people.