We are searching data for your request:
Upon completion, a link will appear to access the found materials.
At the moment I'm especially interested in the question of whether biological sex is really a spectrum. Unfortunately I could not find any good answers on the Internet. Therefore I hope that some of you might be able to present the current state of science here and whether it is already generally accepted in biological science that sex is a spectrum.
What I am confused about here is for something to be a spectrum it must have some some sort of distribution along a parametrised scales. For example, it would be daft to think height to be binary even though there are tall people and short people. Tall and short are relative; height is defined by a continuous factor, length, measured from foot to head. There is no such parameter that can be used to show that male and female are relative in the way that tall and short are. There is no scale. What I thought is that it relies on the binary to classify gonads as either male or female. So, people with disorders of sex development are still either male or female due to the presence of gonads (which define sex) if I understood correctly. There are only two gonad types since this is the fundamental feature of what sex is. I hope someone can correct me here, if this is wrong.
First gender and sex are not the same thing; as an old teacher of mine glibly put it, "sex is plumbing, gender is clothing," and even that is a gross generalization. The problem you are running into is using imprecise terms to ask a scientific question (sex, gender, and spectrum are all imprecise terms in biology). Precision in language is important in science to avoid confusion. The more vague your terms the less precise an answer can be.
More importantly gender isn't really a biological term; it is a sociological term, in particular it is a form of social construct (like countries, currency, or social class). The closest you get in biology is mating strategy, in which case there are species with multiple alternative mating strategies, including species with more mating strategies than sexes, some that are quite drastically different. Humans in particular have a very wide range of complex mating strategies, and of course some are more common than others.
Spectrum is also a tricky word in biology; would you call hair color a spectrum even though the distribution is non-uniform? How about handedness or ear lobe shape? They are both multimodal. Quite often in behavior there are evolutionary stable strategies that are only stable as multimodal distributions; are they spectra?
Even sex is tricky in biology. Since you have phenotypic sexes and chromosomal sexes, there are XY females in humans, as well as XX, XO, and XXX females. There are people with neither testes nor ovaries (both are gonads BTW), and humans with both testes and ovaries. So you end up with quite a variety of "sexes". Then you have things like chimerism in which an individual is really two individual cell lines fused together; even the term "individual human" can get tricky if you look close enough because biology is messy and doesn't respect our generalized human categories.
Short answer: it's messy, and probably no answer will satisfy everyone.
I'm only going to consider sex (I'm not going to mess with "gender") in humans.
- It's reasonable to consider sex as multidimensional rather than one-dimensional; see the various definitions listed below. The same individual could have different karyotypic, morphological, and endocrinological "sex".
- Some but not all of the definitions refer to continuous scales, i.e. if you pick one of the continuous measures below (Quigley scale, circulating testosterone level) you can probably find at least one individual in any not-too-narrow interval on that scale.
- It's reasonable to say that many of the continuous measures below are bimodal, i.e. in some random sample of humans there are more people close to 1 or to 6/7 than in the 2-5 range on the Quigley scale; similarly, there would be more people in the ranges of 10-30 ng/dl or 200-500 ng/dl in their testosterone than in between.
Here are some of the possible definitions of sex, drawing on the Wikipedia article mentioned in the comments:
- karyotype (chromosal type): this is discrete (XY, XX, XYY, XO, XXY,… )
Below the level of the chromosome, there's lots of genetic and environmental variation that can change the phenotype (e.g. here)
- morphology (gonads or internal/external genitalia): the Quigley scale referenced in comments above is one way to describe this variation. The Quigley scale could be used to classify phenotype in cases of
- androgen insensitivity syndrome, i.e. someone with at least one Y-chromosome who doesn't respond developmentally in the typical way to androgens such as testosterone
- someone with an XX karyotype and congenital adrenal hyperplasia who has become masculinized
(the section on intersex conditions in the Wikipedia article on sexual differentiation links to these among others) (these are cartoons of external genitalia, in case that's not obvious)
Intermediate morphology can occur in the gonads as well as in the genitalia or internal organs; according to MedLine Plus (US National Library of Medicine), people with "true gonadal intersex" have "[both] ovarian and testicular tissue… in the same gonad (an ovotestis), or the person might have 1 ovary and 1 testis"
- endocrinology (levels of various circulating hormones): researchers most typically consider testosterone (e.g. in this article). This article reports on total serum testosterone in a US health survey. The distribution is indeed bimodal (there's a peak around 10-30 ng/dL for women and 250-600 ng/dL for men), but this article only reports the 10th and 90 percentiles; there could certainly be someone with a circulating testosterone level right in the middle.
Scientists Fred P. Thieme and William J. Schull of the University of Michigan wrote about sexing a skeleton in 1957: “Sex, unlike most phenotypic features in which man varies, is not continuously variable but is expressed in a clear bimodal distribution.” The same is true for chromosomes, sex organs and testosterone.
"Variability in size or composition of gonads, genital morphology, chromosomes and/or hormonal physiology"
Specere in latin means to look, that's why it's used for the color spectrum. The rainbow is often used to represent gender-identity to represent the amorphous nature of the mind.
The distribution of fitness effects for genetic mutations of whole genomes and individual genes is frequently found to be a bimodal distribution with most mutations being either neutral or lethal with relatively few having intermediate effect.
Through the process of meiosis and fertilization (with rare exceptions), each individual is created with zero or one Y-chromosome. The complementary result for the X-chromosome follows, either a double or a single X. Therefore, direct sex differences are usually binary in expression, although the deviations in more complex biological processes produce a range of exceptions, resulting in a bimodal graph.
Gender does means biological sex in the context you use. https://en.wikipedia.org/wiki/Gender
Is Sex a Spectrum?
It appears to be very common these days in fashionable circles to say that sex is not a binary and that sex is indeed a spectrum. Indeed, the idea that we can pigeonhole people into two classes — male and female — is presented as some sort of old fashioned bigotry.
But what could it mean for sex to be a spectrum? W hen we say ‘My sex is X’ what does that mean and what is a sex? The fashionable idea is that X can be a fluid choice between some sort of range. What sort of things can take the place of X in that statement? Is it just ‘male’ and ‘female’ or is there more to it than that?
The concept of a spectrum comes from physics. Physicists study spectra in order to determine the properties of things that emit light or sound or some other wave. Spectra are used to describe certain wave-like phenomena. We can describe the phenomena of light and sound as being wavelike and can exist on a spectrum of possible states described by a single parameter — wavelength, or frequency.
The note of a sound can be objectively described by its wavelength. Middle C has a wavelength of 1.311 meters and a frequency of 261,626 Hz. Red light has a wavelength of between 700–635 nm. When we observe a spectrum from stars, the intensity of light at each wavelength can tell us a great deal about the physical properties of the star. Spectra are useful concepts that help us describe and quantify wave-like phenomena. The title image is the spectrum emitted by our Sun. The black lines are absorption lines and tells us the composition of the Sun’s atmosphere.
The term ‘spectrum’ has been adopted into other areas of science and society. For example, we might talk of political views existing on a spectrum between left and right. This has some utility but, as we can see in today’s politics, this quickly breaks down as a useful metaphor. How can we define any particular scale that allows us to place people along a line of political views? That would not allow us to discriminate between the various political groupings that exist. People may be socially liberal but have very different views on financial and taxation policy. Political views do not have a ‘single’ spectrum associated with them. Politics is massively multi-dimensional and views tend to cluster into multiple related sets of opinions and values.
Medicine borrows the term spectrum too. We have all heard of the Autism Spectrum. But again it is only a metaphor as autism is not characterised by a single scale of intensity of any particular symptom. It is a series of neuro-developmental disorders with distinct characteristics.
So, it’s fairly common to see the concept of a spectrum used as a metaphor, but also to see that this metaphor can be more unhelpful at times than it is helpful. It is misleading to see politics as a spectrum of views. It is wrong to think of autism as just being a spectrum.
So, what about sex as a spectrum? Clearly there is nothing in the concept of sex that we could measure as a continuous function of wavelength etc. At best, we might be dealing with another metaphor.
It’s probably worth noting that sex describes reproductive roles. Any description of sex that does not take into account reproduction at some level is clearly unanchored and absurd. Specifically, when someone says their sex is X, a coherent and material explanation is that they are saying their bodies have developed along one of two pathways towards the production of specific gonads that produce specific gametes associated with each sex.
For many people, succesful production of gametes and reproduction does not occur — this is contingent on environmental and historical factors — a boy child may die at five before sperm are produced — they are still male — their development is still clearly along the male pathway. And of course, like any biological pathway, problems can occur and atypical development can occur due to chromosomal/genetic issues. Sometimes misleadingly called intersex conditions, these disorders of sex development are still variations on the development of one of two sexes.
So, where does the idea of a spectrum come from? Firstly, whilst sex is described by function, there is still a wide variation in the distribution of form. In short, and not to put too fine a point on it, sizes can vary.
Yes, height can vary enormously between sexes on average. And each sex, can see wide distributions in height. Men tend to be taller than women. But there is no height where males become females or vice versa. This goes for other characteristics too, like hormone levels etc. If we were to plot a spectrum of heights of people we would see a bimodal distribution of those heights. We are not seeing a bimodal distribution of sex though — a common misconception — as the x-axis would still be height. Sex might be the underlying cause of the bimodal distribution precisely because there are two discrete values that sex can have with distributions around an average for each of the two possible sexes. Such arguments do not show sex is a spectrum but quite the reverse: they are very strong evidence that humans are sexually dimorphic.
Perhaps the most misleading representation of ‘sex as a spectrum’ uses intersex conditions to suggest somehow that such conditions ‘move the line’ on what someone’s sex is. This diagram is most egregious…
It shows a series of different intersex conditions but lays them out as if they can be characterised along a spectrum. To force the point, a rainbow light spectrum is shown above. This is thoroughly misleading. What is being shown here are two sexes, male and female, and the different conditions that can occur with each. There is no natural distribution that could represent the x-axis here. It is artificially arranged. I suspect deliberately so, for ideological reasons.
And it is these ideological ‘gender’ ideas that are pushing ‘sex as a spectrum’. The idea is to undermine our understanding of what sex is & how humans can have a sex. It prevents proper descriptions and allows the subjective idea of gender to take prominence over objective sex.
There are winners and losers in this ideological stance. If sex is a subjective idea with artificial lines drawn on a spectrum, just as ‘red’ is a rather arbitrary range on the colour spectrum, then we should not pay too much attention to it. Rather, we should privilege the self-declared concept of gender that allow people to be ‘what they truly are’ — whatever that means. Females — women — no longer really exist. Their rights and spaces are just unimportant artefacts of ‘old science’.
This needs to be resisted and challenged by all those who care about the truth and by all those who seek justice. Sex is not a spectrum. It is the material reality of male and female for us all, and has material consequences for us all.
Biologists in WSJ: Only Two Sexes, Male and Female, There is No Sex 'Spectrum'
In a powerful commentary in the Feb. 3 edition of The Wall Street Journal, biologists Colin Wright and Emma Hilton explain that, scientifically, there are only two sexes, male and female, and there is no sex "spectrum." They also stress that "biologists and medical professionals" must stop being politically correct and "stand up for the empirical reality of biological sex."
With the phenomenon of some men saying they "identify" as women and some women saying they "identify" as men, or any "gender identity" combination therein, "we see a dangerous and anti-scientific trend toward the outright denial of biological sex," state the biologists Wright and Hilton.
This notion that there is a sex "spectrum," where people can choose "to identify as male or female," regardless of their anatomy, is irrational and has "no basis in reality," say the biologists. "It is false at every conceivable scale of resolution."
As they explain, "In humans, as in most animals or plants, an organism’s biological sex corresponds to one of two distinct types of reproductive anatomy that develop for the production of small or large sex cells—sperm and eggs, respectively—and associated biological functions in sexual reproduction."
"In humans, reproductive anatomy is unambiguously male or female at birth more than 99.98% of the time," they write. "The evolutionary function of these two anatomies is to aid in reproduction via the fusion of sperm and ova."
"No third type of sex cell exists in humans, and therefore there is no sex “spectrum” or additional sexes beyond male and female," state the biologists. "Sex is binary."
Furthermore, "the existence of only two sexes does not mean sex is never ambiguous," write Hilton and Wright. "But intersex individuals are extremely rare, and they are neither a third sex nor proof that sex is a 'spectrum' or a 'social construct.'"
The two scientists go on to explain that those "most vulnerable to sex denialism are children" because "gender identity" instead of biological sex can cause confusion. Puberty-blocking drugs and "affirmation therapies" that reinforce this confusion may contribute to gender dysphoria, say Hilton and Wright.
They add that this "pathologizing of sex-atypical behavior is extremely worrying and regressive. It is similar to gay 'conversion' therapy, except that it’s now bodies instead of minds that are being converted to bring children into 'proper' alignment with themselves."
In conclusion, they state, "The time for politeness on this issue has passed. Biologists and medical professionals need to stand up for the empirical reality of biological sex. When authoritative scientific institutions ignore or deny empirical fact in the name of social accommodation, it is an egregious betrayal to the scientific community they represent. It undermines public trust in science, and it is dangerously harmful to those most vulnerable."
Colin Wright is an evolutionary biologist at Penn State. Emma Hilton is a developmental biologist at the University of Manchester.
Science Says There Are Only Two Genders, No Gender 'Spectrum'
In the increasingly brainwashed world we live in, it is incredibly refreshing when experts are willing to speak the politically incorrect truth. In Thursday’s edition of the Wall Street Journal, biologists Colin M. Wright and Emma N. Hilton provide extensive commentary on the transgender fad and the notion of gender fluidity. What does the science say? In short, it says that are only two genders: male and female.
Sadly, such an obvious conclusion can get you branded as a bigot these days
And what about the gender “spectrum” and gender being a social construct? Wright and Hilton completely destroy the basis of these concepts. “If male and female are merely arbitrary groupings, it follows that everyone, regardless of genetics or anatomy should be free to choose to identify as male or female, or to reject sex entirely in favor of a new bespoke ‘gender identity,'” they write. “To characterize this line of reasoning as having no basis in reality would be an egregious understatement. It is false at every conceivable scale of resolution.”
They explain that “In humans, reproductive anatomy is unambiguously male or female at birth more than 99.98% of the time.” Humans, just like most animals and plants, have two distinct biological sexes with the corresponding anatomy for reproduction. “No third type of sex cell exists in humans, and therefore there is no sex ‘spectrum’ or additional sexes beyond male and female. Sex is binary.”
According to Wright and Hilton, denying the “reality of biological sex” in favor of subjective “gender identity” raises “serious human-rights concerns for vulnerable groups including women, homosexuals and children.”
Women have fought hard for sex-based legal protections. Female-only spaces are necessary due to the pervasive threat of male violence and sexual assault. Separate sporting categories are also necessary to ensure that women and girls don’t have to face competitors who have acquired the irreversible performance-enhancing effects conferred by male puberty. The different reproductive roles of males and females require laws to safeguard women from discrimination in the workplace and elsewhere. The falsehood that sex is rooted in subjective identity instead of objective biology renders all these sex-based rights impossible to enforce.
Denying biological sex also “erases homosexuality” since “same-sex attraction is meaningless without the distinction between the sexes.”
Many activists now define homosexuality as attraction to the “same gender identity” rather than the same sex. This view is at odds with the scientific understanding of human sexuality. Lesbians have been denounced as “bigots” for expressing a reluctance to date men who identify as women. The successful normalization of homosexuality could be undermined by miring it in an untenable ideology.
Of course, the most vulnerable to transgender ideology are children. “When they’re taught that sex is grounded in identity instead of biology, sex categories can easily become conflated with regressive stereotypes of masculinity and femininity.” They note that the vast majority of gender-confused youth outgrow their feelings during puberty, many of which later identify as homosexual adults.
To these experts, “The time for politeness on this issue has passed,” and they are calling on biologists and medical professionals to “stand up for the empirical reality of biological sex.”
We Know Sexuality Is a Spectrum — Here’s What That Looks Like & What It Means
We&rsquove all heard of the term “spectrum,” used to describe everything from colors to mental health, but what does it mean when applied to gender and sexuality? As the world has further explored the deepest parts of sexual identity and orientation, spectrums have been created to help people figure out how to talk about a deeply intimate part of your identity. Spectrums also are a useful tool for researchers and educators who are often tasked with explaining the concepts of gender and sexuality to the general public.
What is a spectrum?
First things first: In this context, a spectrum is a tool (often shown with single-line chart) that has a descriptor on one end and the opposite descriptor on the other end. For example, a common gender spectrum you might see (which is a different thing from sexuality) would have female on one side and male on the other side with space in the middle for those who identify as neither male nor female (such as nonbinary and gender nonconforming folks).
The Kinsey scale
One of the most famous spectrums is the Kinsey scale. The Kinsey scale is a numerical heterosexual-homosexual rating system created in 1948 by Dr. Alfred Kinsey, according to the Kinsey Institute at Indiana University. This scale has heterosexual as 0 on one end and homosexual as 6 on the other end, with 3 in the middle for those who identify as equally hetero and homosexual (or bisexual). It also has an &ldquoX&rdquo option for those who do not have sexual relationships, or as we call it now, people who are asexual. The scale was one of the first academic tools that challenged perception of sexuality and began discussions that still continue today.
While the Kinsey scale is one of the oldest spectrums and historically important, some don’t consider it the best spectrum for the current state of gender and sexuality. For example, queer educator Lindsay Amer tells SheKnows that the Kinsey scale is &ldquopretty black and white” and “doesn&rsquot really take sexuality into account outside of homo and heterosexual and it&rsquos super-simplistic about asexuality.&rdquo
The Kinsey scale only allows for one type of asexuality (which itself is an entire spectrum) and assumes that all attraction is specifically toward men and women, which we know now is not the only kind of attraction, Amer explains.
Other types of scales
Spectrums go far beyond gender and sexual orientation &mdashthey can also measure romantic attraction and relationship style (asexuality, aromanticism and grey-sexual identities can fall on these). There are also spectrums that exist within specific communities, such as the kink spectrum.
&ldquoOn one end [of the kink spectrum], you have submissives, or bottoms,&rdquo Zoe Whitney, the founder of SSASE (an educational group for submissive women and nonbinary people), tells SheKnows, &ldquoand on the opposite end, you have dominants or tops. And right in the middle of the scale sits the switch, someone who enjoys both.”
According to Whitney, the best part about using this model in the kink community is that different people or relationships can help inspire different places on the spectrum, “so with one person, you might fall closer to submissive, and with someone else, you might be closer to dominant.&rdquo
Along the same lines, Amer notes, &ldquoSpectrums help us describe different facets of our identity because they represent every possible gender, sexuality, attraction and expression.&rdquo This is important because many people struggle to firmly articulate their identity, and spectrums help people define who they are, especially if they exist outside binaries.
Why does any of this matter?
Spectrums are important because they reinforce that our world does not exist in black-and-white binaries. A great way to understand this outside gender and sexuality is to use liking/disliking specific foods. For example, on one end of the broccoli-liking spectrum is the statement, &ldquoI love broccoli,&rdquo and on the other end is, &ldquoI hate broccoli.&rdquo You may fall on one end of the spectrum, but a lot of people will also fall somewhere in the middle. Maybe they like broccoli sometimes or only like broccoli steamed or on pizza. People who identify in the middle of the broccoli-liking spectrum need a place to exist that isn&rsquot in the strict love/hate binary.
This same concept can be applied to gender or sexuality &mdash people are complex animals that can’t be understood in binary terms.
It’s also important (and exciting) to note that new spectrums are created all the time. As we discover and talk about new aspects of identity, we create spectrums to help us to define and describe who we are. It can be vulnerable and intimidating sharing these intimate parts of ourselves
For more information on spectrums, check out some of the resources available, including SexInfoOnline, Queer Kid Stuff’s “What Is a Spectrum. ” video, “The Kinsey Scale” and Ash Hardell’s “Queer, Asexual and Gender Spectrums!” video.
Yet it’s one thing to claim that a man can “identify” as a woman or vice versa. Increasingly we see a dangerous and antiscientific trend toward the outright denial of biological sex.
“The idea of two sexes is simplistic,” an article in the scientific journal Nature declared in 2015. “Biologists now think there is a wider spectrum than that.” A 2018 Scientific American piece asserted that “biologists now think there is a larger spectrum than just binary female and male.” And an October 2018 New York Times headline promised to explain “Why Sex Is Not Binary…” To characterize this line of reasoning as having no basis in reality would be an egregious understatement. It is false at every conceivable scale of resolution.
The time for politeness on this issue has passed. Biologists and medical professionals need to stand up for the empirical reality of biological sex. When authoritative scientific institutions ignore or deny empirical fact in the name of social accommodation, it is an egregious betrayal to the scientific community they represent. It undermines public trust in science, and it is dangerously harmful to those most vulnerable.
The scientific profession has been quite vocal about enforcing censorship of criticism of Darwinian “science” and Global Warming “science” in classrooms. Yet the major scientific journals, and leading scientific organizations such as the National Academy of Sciences and the American Association for the Advancement of Science, have failed to affirm elemental realities. It is a rudimentary scientific fact that human sex is binary, that human life begins at conception, and that intelligent design is evident in living things. And don’t forget — the scientists who remain silent on these obvious facts also remained utterly silent when their paychecks flowed from Jeffrey Epstein.
Is Sex Binary?
In her New York Times op-ed “Why Sex Is Not Binary,” the biologist and gender studies theorist Anne Fausto-Sterling tries to set the record straight: “Two sexes have never been enough to describe human variety.” According to Fausto-Sterling, it has “long been known” that some people are neither female nor male (or, perhaps, both female and male).
Fausto-Sterling is responding to a leaked draft memo from the Department of Health and Human Services that proposes a legal definition of sex under Title IX “based on immutable biological traits.” The memo appears to be part of a regrettable attempt to remove some legal protections from people who are transgender. Although a transgender person is no less likely to be female or male than someone who is not transgender, activists for transgender rights often cite the alleged fact that “sex is not binary” to support the idea that being transgender is not a mental health condition, but instead is merely “normal biological variation.” That “sex is a spectrum,” or — as Fausto-Sterling wrote in The New York Times 25 years ago — that “there are at least five sexes,” are claims that are pressed into similar service. Fausto-Sterling’s article endorses and reinforces these ideas. But not only are the claimed biological facts far from established, this particular use of biology to guide social and legal issues is completely misguided in the first place. Transgender people, just like anyone else, should be free to live and work without being stigmatized, harassed, or disrespected. Whether sex is binary, a spectrum, or whether there are 42 sexes, makes absolutely no difference.
Let’s start with the biology. Fausto-Sterling’s approach to whether some people are neither female nor male is rather indirect. She explains the psychologist John Money’s many-fold distinction between chromosomal sex, external genital sex, pubertal hormonal sex, and others. She points out that these do not always align. For instance, there are people who are chromosomally male (XY) but whose external genitalia are female. Fausto-Sterling also notes that Money’s “layers of sex” are not themselves binary: there are sex-chromosome combinations other than XX and XY, and similarly for the other layers.
But where are the original categories of female and male, supposedly the topic of Fausto-Sterling’s article? They seem to have disappeared, being replaced by chromosomally-female, genitally-female, and so on. Granted, there are some people who have XXY chromosomes, or just a single X, making them neither chromosomally female nor chromosomally male. But the question was not whether chromosomal sex is binary, it was whether sex is binary. That question has been evaded, not answered.
The categories of female and male are in fact implicit in Money’s taxonomy. To be chromosomally female is to have the sex chromosomes typical of (human) females to be genitally female is to have the genitalia typical of (human) females, and so on. But what is it to be, simply, female or male? Forget Money’s many sex-related categories — what are the sexes?
The answer has been known since the 19th century. As Simone de Beauvoir puts it in The Second Sex (the founding text of modern feminism), the sexes “are basically defined by the gametes they produce.” Specifically, females produce large gametes (reproductive cells), and males produce small ones. (Since there are no species with a third intermediate gamete size, there are only two sexes.¹) A glance at the huge variety of females and males across the animal and vegetable kingdoms will confirm that there is nothing else the sexes can be. For instance, the equation female=XX is confused for a fundamental reason having nothing to do with human chromosomal variation: females of numerous species either have different sex chromosomes (as in birds) or else no sex chromosomes at all (as in some reptiles). The XX/XY system is merely the mechanism by which placental mammals like humans typically become female and male other animals and plants use different means to achieve the same end result. Whenever it is suggested that being female or male is a matter of having certain chromosomes (or primary/secondary sex characteristics), that is a sure sign that the discussion has gone off the rails.
There is a complication. Females and males might not produce gametes for a variety of reasons. A baby boy is male, despite the fact that sperm production is far in his future (or even if he dies in infancy), and a post-menopausal woman does not cease to be female simply because she no longer produces viable eggs. Female worker honeybees are usually incapable of producing eggs because their ovarian development has been inhibited by chemicals secreted by the queen. (In one species of bee, the female workers are all permanently sterile, even in queenless colonies.)
In the light of these examples, it is more accurate (albeit not completely accurate) to say that females are the ones who have advanced some distance down the developmental pathway that results in the production of large gametes — ovarian differentiation has occurred, at least to some extent. Similarly, males are the ones who have advanced some distance down the developmental pathway that results in the production of small gametes. Definitions in biology are never perfectly precise, and these are no exception. Still, they give us some traction in examining whether there are any humans who are neither female nor male. (It is not in dispute that some non-human organisms are neither female nor male, and that some — hermaphrodites — are both.)
Consider, for example, the “intersex” condition Congenital Adrenal Hyperplasia — one of many “disorders of sex development” (DSDs). XX individuals with this rare condition can have an enlarged clitoris at birth (sometimes very penis-like), due to high levels of androgen hormones in the womb. They have progressed some considerable way down the developmental pathway that produces eggs (they have the usual ovaries and fallopian tubes), and have not even started down the (male) sperm-producing pathway. They are sometimes assigned male at birth, but are usually raised as girls, and indeed many of them go on to have children. Whether they are raised as girls or boys, the scientific literature correctly classifies them as female. As might expected, there are some other rare cases (arguably 1 in 50,000 births or even rarer) that are hard to decide, but there are no clear and uncontroversial examples of humans who are neither female nor male. (A similar point goes for supposed examples of humans who are both female and male, although here things get more complicated.)
The existence of some unclear cases shows that it would be incautious to announce that sex (in humans) is binary. By the same token, it is equally incautious to announce that it isn’t — let alone that this is an established biological fact. And even if some people are outside the binary, they are a miniscule fraction of the population, nothing like the frequently cited 1–2 percent figure, which draws on Fausto-Sterling’s earlier work.²
That sex is not binary is evidently something that many progressives dearly wish to believe, but a philosophically sound case for treating everyone with dignity and respect has absolutely no need of it. People with intersex conditions have historically been subject to ethically dubious genital surgery as children, or deceived about their medical status by (usually well-meaning) doctors. It would be a huge mistake to think that such surgery is unjustified because the patients fall outside the binary, and so should not be surgically fashioned to appear to be within it. The main arguments against surgery (there are risks with little compensating benefit, and patients are too young to consent) have nothing to do with whether the patients are female, male, both, or neither.
Further, the issue of whether sex is binary, although of academic interest, is of no relevance to current debates about transsexuality and the changing models for treating gender dysphoria. To those struggling with gender identity issues, it might seem liberating and uplifting to be told that biological sex in humans is a glorious rainbow, rather than a square conservatively divided into pink and blue halves. But this feel-good approach is little better than deceiving intersex patients: respect for autonomy demands honesty. And finally, if those advocating for transgender people (or anyone else) rest their case on shaky interpretations of biology, this will ultimately only give succor to their enemies.
¹In this sense, sex is binary: there are only two sexes. However, the interpretation of “sex is binary” relevant to the present debate is different: everyone is either female or male, and no one is both.
²The source for the 1–2 percent figure is Fausto-Sterling’s co-authored 2000 paper “How Sexually Dimorphic Are We?”. That paper estimated the “frequency of intersex” at 1.7 percent. A neglected response by the philosopher Carrie Hull corrected “numerous errors and omissions” in the data collection and interpretation, bringing the figure down to 0.37 percent. Importantly, that figure is not an estimate of the frequency of “intersex conditions” as usually understood, but rather includes any failure to (in Fausto-Sterling’s words) “conform to a Platonic ideal” of femaleness and maleness. By this over-inclusive criterion, XYY individuals, who are practically indistinguishable from normal XY males, are counted as intersex. The true figure for intersex conditions (understood as those where the phenotype has both female and male elements — a small subset of DSDs) is closer to 0.018 percent, about 100 times lower than the figure supplied by Fausto-Sterling (see Leonard Sax, “How Common Is Intersex? A Response To Anne Fausto‐Sterling”). Incorporating Hull’s corrections drops that percentage to 0.015. The present point is that even people in this 0.015 percent usually fall within the female/male binary, and that no one clearly falls beyond it. (There actually are more plausible candidates for exceptions to the female/male binary than the classic intersex conditions comprising this 0.015 percent, in particular XY gonadal dysgenesis or Swyer Syndrome.)
She wasn’t especially tall. Her testosterone levels weren’t unusually high for a woman. She was externally entirely female. But in the mid-1980s, when her chromosome results came back as XY instead of the “normal” XX for a woman, the Spanish national team ousted hurdler María José Martínez-Patiño. She was ejected from the Olympic residence and deserted by her teammates, friends, and boyfriend. She lost her records and medals because of a genetic mutation that wasn’t proven to give her any competitive advantage.
People like Martínez-Patiño have been ill-served by rules that draw a hard line between the sexes. In the U.S., the Trump administration looks set to make things worse. According to a memo leaked to the New York Times in October, the U.S. Department of Health and Human Services is trying to set up a legal binary definition of sex, establishing each person “as male or female based on immutable biological traits identifiable by or before birth.” But our bodies are more complicated than that.
An increasing recognition of this complexity by researchers and the public has affirmed that gender sits on a spectrum: People are more and more willing to acknowledge the reality of nonbinary and transgender identities, and to support those who courageously fight for their rights in everything from all-gender bathrooms to anti–gender discrimination laws. But underlying all of this is the perception that no matter the gender a person identifies as, they have an underlying sex they were born with. This represents a fundamental misunderstanding about the nature of biological sex. Science keeps showing us that sex also doesn’t fit in a binary, whether it be determined by genitals, chromosomes, hormones, or bones (which are the subject of my research).
The perception of a hard-and-fast separation between the sexes started to disintegrate during the second wave of feminism in the 1970s and 1980s. In the decades that followed, we learned that about 1.7 percent of babies are born with intersex traits that behavior, body shape, and size overlap significantly between the sexes, and both men and women have the same circulating hormones and that there is nothing inherently female about the X chromosome. Biological realities are complicated. People living their lives as women can be found, even late in life, to be XXY or XY.
Skeletal studies, the field that I work in as a doctoral student in anthropology, and the history of this field show how our society’s assumptions about sex can lead to profound mistakes, and how acknowledging that things are not really as binary as they may seem can help to resolve those errors. Trump and his advisers should take note.
If you’ve ever watched the TV series Bones, you’ve heard Temperance “Bones” Brennan, the show’s protagonist and star forensic anthropologist, call out to her colleagues whether the skeleton she’s analyzing is male or female. That’s because sex distinctions are very helpful to know for missing persons and archaeological sites alike. But just how easy is it to make this determination?
In the early 1900s, the U.S.-based anthropologist Aleš Hrdlička helped to found the modern study of human bones. He served as the first curator of physical anthropology at the U.S. National Museum (now the Smithsonian Institution). The skeletons Hrdlička studied were categorized as either male or female, seemingly without exception. He was not the only one who thought sex fell into two distinct categories that did not overlap. Scientists Fred P. Thieme and William J. Schull of the University of Michigan wrote about sexing a skeleton in 1957: “Sex, unlike most phenotypic features in which man varies, is not continuously variable but is expressed in a clear bimodal distribution.” Identifying the sex of a skeleton relies most heavily on the pelvis (for example, females more often have a distinctive bony groove), but it also depends on the general assumption that larger or more marked traits are male, including larger skulls and sizable rough places where muscle attaches to bone. This idea of a distinct binary system for skeletal sex pervaded and warped the historical records for decades.
In 1972 Kenneth Weiss, now a professor emeritus of anthropology and genetics at Pennsylvania State University, noticed that there were about 12 percent more male skeletons than females reported at archaeological sites. This seemed odd, since the proportion of men to women should have been about half and half. The reason for the bias, Weiss concluded, was an “irresistible temptation in many cases to call doubtful specimens male.” For example, a particularly tall narrow-hipped woman might be mistakenly cataloged as a man. After Weiss published about this male bias, research practices began to change. In 1993, 21 years later, the aptly named Karen Bone, then a master’s student at the University of Tennessee–Knoxville, examined a more recent data set and found that the bias had declined: The ratio of male to female skeletons had balanced out. That might in part be because of more accurate ways of sexing skeletons. But when I went back through the papers Bone cited, I noticed there were more individuals categorized as “indeterminate” after 1972 and basically none prior.
Allowing skeletons to remain unsexed, or “indeterminate,” reflects an acceptance of the variability and overlap between the sexes. It does not necessarily mean that the skeletons classified this way are, in fact, neither male nor female, but it does mean that there is no clear or easy way to tell. As science and social change in the 1970s and 1980s revealed that sex is complicated, the category of “indeterminate sex” individuals in skeletal research became more common and improved scientific accuracy.
For generations, the false perception that there are two distinct biological sexes has had many negative indirect effects. It has muddied historical archaeological records, and it has caused humiliation for athletes around the globe who are closely scrutinized. In the mid-1940s, female Olympic athletes went through a degrading process of having their genitals inspected to receive “femininity certificates.” This was replaced by chromosome testing in the late 1960s, and subsequently hormone testing. But instead of rooting out imposters, these tests illustrated the complexity of human sex.
It might be more convenient for the U.S. federal government to have a binary system for determining legal sex many U.S. laws and customs are built on this assumption. But just because it’s a convenient system of classification doesn’t mean it’s right. Some countries, such as Canada, and some states in the U.S., including Oregon, now allow people to declare a nonbinary gender identity on their driver’s license or other identification documents. In a world where it is apparently debatable whether anti-discrimination laws apply to sex or gender, it is a step in the wrong direction to be writing either into law as a strictly binary phenomenon.
The famous cases of strong, athletic, and audacious female athletes who have had their careers derailed by the Olympic “gender tests” exemplify how misguided it is to classify sex or gender as binary. These women are, like all of us, part of a sex spectrum, not a sex binary. The more we as a society recognize that, the less we will humiliate and unnecessarily scrutinize people—and the less discriminatory our world will be.
Gender identity is our internal experience and naming of our gender. It can correspond to or differ from the sex we were assigned at birth.
Understanding of our gender comes to most of us fairly early in life. According to the American Academy of Pediatrics, “By age four, most children have a stable sense of their gender identity.” This core aspect of one’s identity comes from within each of us. Gender identity is an inherent aspect of a person’s make-up. Individuals do not choose their gender, nor can they be made to change it. However, the words someone uses to communicate their gender identity may change over time naming one’s gender can be a complex and evolving matter. Because we are provided with limited language for gender, it may take a person quite some time to discover, or create, the language that best communicates their internal experience. Likewise, as language evolves, a person’s name for their gender may also evolve. This does not mean their gender has changed, but rather that the words for it are shifting.
The two gender identities most people are familiar with are boy and girl (or man and woman), and often people think that these are the only two gender identities. This idea that there are only two genders–and that each individual must be either one or the other–is called the “Gender binary.” However, throughout human history we know that many societies have seen, and continue to see, gender as a spectrum, and not limited to just two possibilities. In addition to these two identities, other identities are now commonplace.
Youth and young adults today no longer feel bound by the gender binary, instead establishing a growing vocabulary for gender. More than just a series of new words, however, this shift in language represents a far more nuanced understanding of the experience of gender itself. Terms that communicate the broad range of experiences of non-binary people are particularly growing in number. Genderqueer, a term that is used both as an identity and as an umbrella term for non-binary identities, is one example of a term for those who do not identify as exclusively masculine or feminine. This evolution of language is exciting, but can also be confusing as new terms are created regularly, and since what a term means can vary from person to person. For further information on specific identities and what they commonly mean, please see “The Language of Gender.”
Sex differences in medicine include sex-specific diseases, which are diseases that occur only in people of one sex and sex-related diseases, which are diseases that are more usual to one sex, or which manifest differently in each sex. For example, certain autoimmune diseases may occur predominantly in one sex, for unknown reasons. 90% of primary biliary cirrhosis cases are women, whereas primary sclerosing cholangitis is more common in men. Gender-based medicine, also called "gender medicine", is the field of medicine that studies the biological and physiological differences between the human sexes and how that affects differences in disease. Traditionally, medical research has mostly been conducted using the male body as the basis for clinical studies. Similar findings are also reported in the sport medicine literature where males typically account for >60% of the individuals studied.  The findings of these studies have often been applied across the sexes and healthcare providers have assumed a uniform approach in treating both male and female patients. More recently, medical research has started to understand the importance of taking the sex into account as the symptoms and responses to medical treatment may be very different between sexes. 
Neither concept should be confused with sexually transmitted diseases, which are diseases that have a significant probability of transmission through sexual contact.
Sex-related illnesses have various causes: [ citation needed ]
- genetic illnesses
- Parts of the reproductive system that are specific to one sex
- Social causes that relate to the gender role expected of that sex in a particular society.
- Different levels of prevention, reporting, diagnosis or treatment in each gender.
Sex differences in human physiology are distinctions of physiological characteristics associated with either male or female humans. These can be of several types, including direct and indirect, direct being the direct result of differences prescribed by the Y-chromosome (due to the SRY gene), and indirect being characteristics influenced indirectly (e.g., hormonally) by the Y-chromosome. Sexual dimorphism is a term for the phenotypic difference between males and females of the same species.
Through the process of meiosis and fertilization (with rare exceptions), each individual is created with zero or one Y-chromosome. The complementary result for the X-chromosome follows, either a double or a single X. Therefore, direct sex differences are usually binary in expression, although the deviations in more complex biological processes produce a menagerie of exceptions.
Indirect sex differences are general differences as quantified by empirical data and statistical analysis. Most differing characteristics will conform to a bell-curve (i.e., normal) distribution which can be broadly described by the mean (peak distribution) and standard deviation (indicator of size of range). Often only the mean or mean difference between sexes is given. This may or may not preclude overlap in distributions. For example, most males are taller than most females,  but an individual female could be taller than an individual male. The extents of these differences vary across societies.  [ improper synthesis? ]
The most obvious differences between males and females include all the features related to reproductive roles, notably the endocrine (hormonal) systems and their physiological and behavioral effects, including gonadal differentiation, internal and external genital and breast differentiation, and differentiation of muscle mass, height, and hair distribution. There are also differences in the structure of specific areas of the brain. For example, on average, the SDN (INAH3 in humans) has been repeatedly found to be considerably larger in males than in females. 
Research on biological sex differences in human psychology investigates cognitive and behavioral differences between men and women. This research employs experimental tests of cognition, which take a variety of forms. Tests focus on possible differences in areas such as IQ, spatial reasoning, aggression, emotion, and brain structure and function.
Chromosomal makeup is important in human psychology. Women typically have two X chromosomes while males typically have an X and a Y chromosome. The X chromosome is more active and encodes more information than the Y chromosome, which has been shown to affect behavior.  Genetic researchers theorize that the X chromosome may contain a gene influencing social behaviours.  [ better source needed ]
Most IQ tests are constructed so that there are no overall score differences between females and males. Areas where differences have been found include verbal and mathematical ability.   IQ tests that measure fluid g and have not been constructed to eliminate sex differences also tend to show that sex differences are either non-existent or negligible.   2008 research found that, for grades 2 to 11, there were no significant gender differences in math skills among the general population.  Differences in variability of IQ scores have been observed in studies, with more men falling at the extremes of the spectrum.  
Because social and environmental factors affect brain activity and behavior, where differences are found, it can be difficult for researchers to assess whether or not the differences are innate. Some studies showing that differences are due to socially assigned roles (nurture), while other studies show that differences are due to inherent differences (natural or innate).  Studies on this topic explore the possibility of social influences on how both sexes perform in cognitive and behavioral tests. Stereotypes about differences between men and women have been shown to affect a person's behavior (this is called stereotype threat).  
In his book titled Gender, Nature, and Nurture, psychologist Richard Lippa found that there were large differences in women's and men's preferences for realistic occupations (for example, mechanic or carpenters) and moderate differences in their preferences for social and artistic occupations. His results also found that women tend to be more people-oriented and men more thing-oriented. 
Hartung & Widiger (1998) found that many kinds of mental illnesses and behavioral problems show gender differences in prevalence and incidence. "Of the 80 disorders diagnosed in adulthood for which sex ratios are provided, 35 are said to be more common in men than in women (17 of which are substance related or a paraphilia), 31 are said to be more common in women than men, and 14 are said to be equally common in both sexes." 
Differences in male and female jealousy can also be observed. While female jealousy is more likely to be inspired by emotional infidelity, male jealousy is most likely to be brought on by sexual infidelity. A clear majority of approximately 62% to 86% of women reported that they would be more bothered by emotional infidelity and 47% to 60% of men reported that they would be more bothered by sexual infidelity. 
In 2005, Janet Shibley Hyde from the University of Wisconsin-Madison introduced the gender similarities hypothesis, which suggests that males and females are similar on most, but not all, psychological variables. The research focused on cognitive variables (for example, reading comprehension, mathematics), communication (for example, talkativeness, facial expressions), social and personality (for example, aggression, sexuality), psychological well-being, and motor behaviors. Using results from a review of 46 meta-analyses, she found that 78% of gender differences were small or close to zero. A few exceptions were some motor behaviors (such as throwing distance) and some aspects of sexuality (such as attitudes about casual sex), which show the largest gender differences. She concludes her article by stating: "It is time to consider the costs of overinflated claims of gender differences. Arguably, they cause harm in numerous realms, including women’s opportunities in the workplace, couple conflict and communication, and analyses of self-esteem problems among adolescents."  Hyde also stated elsewhere that "variations within genders are greater than variations between genders."  However, another paper argued that the gender similarities hypothesis was current untestable as formulated because it does not provide a metric for the psychological importance of relevant dimensions, nor a rule for counting dimensions a small number of relevant differences may be more significant than a massive number of trivial similarities. 
In 2011 Irina Trofimova found a significant female advantage in time on the lexical task and on the temperament scale of social-verbal tempo, and a male advantage on the temperament scale of physical endurance which were more pronounced in young age groups and faded in older groups. She suggested that there is a "middle age - middle sex" effect: sex differences in these two types of abilities observed in younger groups might be entangled with age and hormonal changes. The study concluded that a one-dimensional approach to sex differences (common in meta-analytic studies) therefore overlooks a possible interaction of sex differences with age.  This hormones-based "middle age-middle sex effect", and also specifics of the few psychological sex differences (verbal and physical) were analysed in terms of the systemic evolutional tendencies driving sex dimorphism.  
Statistics have been consistent in reporting that men commit more criminal acts than women.   Self-reported delinquent acts are also higher for men than women across many different actions.  Many professionals have offered explanations for this sex difference. Some differing explanations include men's evolutionary tendency toward risk and violent behavior, sex differences in activity, social support, and gender inequality. In particular, Lee Ellis' evolutionary neuroandrogenic theory posits that sexual selection has led to increased exposure to testosterone in males, causing greater competitive behavior which could lead to criminality. 
Despite the difficulty of interpreting them, crime statistics may provide a way to investigate such a relationship from a gender differences perspective. An observable difference in crime rates between men and women might be due to social and cultural factors, crimes going unreported, or to biological factors (for example, testosterone or sociobiological theories). Taking the nature of the crime itself into consideration may also be a factor. Crime can be measured by such data as arrest records, imprisonment rates, and surveys. However, not all crimes are reported or investigated. Moreover, some studies show that men can have an overwhelming bias against reporting themselves to be the victims of a crime (particularly when victimized by a woman), and some studies have argued that men reporting intimate partner violence find disadvantageous biases in law enforcement.    Burton et al. (1998) found that low levels of self control are associated with criminal activity. 
Sometimes and in some places, there are sex differences in educational achievement. This may be caused by sex discrimination in law or culture, or may reflect natural differences in the interests of the sexes. 
Research has been undertaken to examine whether or not there are sex differences in leadership. Leadership positions continue to be dominated by men.     Women were rarely seen in senior leadership positions leading to a lack of data on how they behave in such positions.  The two main lines of research contradict one another, the first being that there are significant sex differences in leadership and the second being that gender does not have an effect on leadership.
Women and men have been surveyed by Gallup each year concerning workplace topics, and when questioned about preferences of a female boss or a male boss, women chose a preference for a male boss 39% of the time, compared to 26% of men displaying preference for a male boss. Only 27% of females would prefer a boss of the same gender.  This preference, among both sexes, for male leadership in the workplace has continued unabated for sixty years, according to the survey results.
Sex differences in religion can be classified as either "internal" or "external". Internal religious issues are studied from the perspective of a given religion, and might include religious beliefs and practices about the roles and rights of men and women in government, education and worship beliefs about the sex or gender of deities and religious figures and beliefs about the origin and meaning of human gender. External religious issues can be broadly defined as an examination of a given religion from an outsider's perspective, including possible clashes between religious leaders and laity  and the influence of, and differences between, religious perspectives on social issues. For example, various religious perspectives have either endorsed or condemned alternative family structures, homosexual relationships, and abortion.  External religious issues can also be examined from the "lens of gender" perspective embraced by some in feminism or critical theory and its offshoots.
Social capital Edit
Sex differences in social capital are differences between men and women in their ability to coordinate actions and achieve their aims through trust, norms and networks.  Social capital is often seen as the missing link in development as social networks facilitate access to resources and protect the commons, while cooperation makes markets work more efficiently.  Social capital has been thought of as women's capital as whereas there are gendered barriers to accessing economic capital, women's role in family, and community ensures that they have strong networks. There is potential that the concept can help to bring women's unpaid 'community and household labor',  vital to survival and development, to the attention of economists. However, research analyzing social capital from a gendered perspective is rare, and the notable exceptions are very critical.   
Sex differences in suicide have been shown to be significant there are highly asymmetric rates of attempted and completed suicide between males and females.  The gap, also called the gender paradox of suicidal behavior, can vary significantly between different countries.  Statistics indicate that males die much more often by means of suicide than females do however, reported suicide attempts are 3 times more common among females than males.  [ better source needed ] This paradox is partially explained by the methodology, with females more often choosing medication-induced overdosage, and males more often turning to weapons such as firearms or knives. 
Financial risk-taking Edit
Sex differences in financial decision making are relevant and significant. Numerous studies have found that women tend to be financially more risk-averse than men and hold safer portfolios.   A May 3, 2015 article in the Wall Street Journal by Georgette Jasen reported that "when it comes to investing, men sometimes have their way of doing things, and women have different ways."  Scholarly research has documented systematic differences in financial decisions such as buying investments versus insurance, donating to ingroups versus outgroups (such as terrorism victims in Iraq versus USA), spending in stores,  and the endowment effect-or asking price for goods people have.  The majority of these studies are based on the theory of agency-communion developed by David Bakan in 1966  according to this theory, due to factors such as socialization, males are typically more agentic (focus on self, upside potential, aggressiveness) and females typically more communal (focus on others, downside potential, and nurturing). This framework robustly explains many financial decision making outcomes.