Gender:  Nature or Nurture?

Foetal Gonad Development
Foetal Gonad Development

What is the definition of sex and gender? How do they compare?

What is the definition of nature and nurture? How do they compare?

Why would Kaitlin Jenner decide now, after years of marriage to become transgender?

Transgender operations are extremely painful. Why would someone undergo that amount of pain?

What determines gender? 

What would you do if at age 14, your parents told you that you were actually born the opposite sex but raised as the other (gender)?

Why do some quite masculine males who are clearly not at that extreme end of the feminine scale – tall, strong, aggressive and excelling in fields like engineering or the military – seek to undergo genital surgery and change their sex roles?

Why do some extremely feminine men and masculine women not seek to make the change?



Let’s talk about sex! Sex is a biological term. It refers to the physical differences between men and women and their reproductive abilities. You are born either a male or female based on chromosomes, genes and hormones. If you believe that your gender identity is caused by nature, you believe you are predisposed to certain traits based on genetics.

Let’s talk about gender! Gender is a psychological term for defining masculine and feminine qualities. Your gender is determined by biological (your awareness of what your sex is and how you react to this), psychological and social influences. The way you act is because of the external influences you have had on your life.

Let’s look at two stories: The first is a sad one about David Reimer who committed suicide after sever ongoing depression, a troubled marriage and financial issues.

After experiencing suicidal thoughts and never truly feeling like a girl, whilst out having an ice-cream Brenda was told by her father that she was actually born a boy Bruce… 14 years earlier, Brenda was born in Canade with a twin brother, Brain. At 6 months of age Bruce’s penis was burned beyond surgical repair after an unconventional circumcision went wrong. After returning home, his parents were lost for what to do. One night they were watching TV and happened to see Dr Money on the TV talking about his theory of gender neutrality. He was a pioneer in the field of gender identity and sexual development. As a reputable psychologist, Bruce’s parents went to see Dr Money. Dr John Money convinced them that it would be possible to raise Bruce as a girl and Brenda was ‘born’. He was dressed like a girl, treated like a girl and even had his testes removed and an artificial ‘flap’ constructed. During his teenage years he was even given oestrogen to induce breast development.

As you could imagine however, after being told he underwent gender reassignment reassuming a masculine identity calling himself David. David later spoke about how he always felt like he didn’t belong, with either the boys or girls. Even though he played with dolls he preferred playing with his brother’s toys and was reported to have been the more aggressive of the twins.

Would you say this story is evidence of nature or nurture influencing our gender identity?

Let’s briefly look at genetics. We are all born with 23 pairs of chromosomes, one of which is responsible for our sex assignment. By default all babies will become girls unless they are born with the Y chromosomes. The Y chromosome is key as it contains the SRY gene. At 6 weeks of age this gene causes the foetal gonads (who are gender neutral until this point) to develop into testes. The testes then produces androgens such as testosterone and MIS (Mullerian (Female internal reproductive ducts) Inhibiting Substance). MIS prevents the male from developing oviducts and the uterus etc. and the other hormones cause the penis to grow. In addition, testosterone has been shown to show that males are more unilateral on the right hemisphere which is responsible for visuo-spatial ability and creativity. At puberty males release more testosterone to develop secondary sexual characteristics e.g. breaking of the voice, muscles, pubic hair etc.

Females do not have the SRY gene which is why they by default develop into a female. The foetal gonads become ovaries and they produces hormones such as oestrogen and progesterone. They do not release testosterone to such a high level as they only produce it in the pituitary gland which is why they are said to be bi-lateral and can use both parts of their brain.

Imagine however you were born with Klinterfelter syndrome were you were born with XXY as a ‘chromosome pair’. You would still have masculine primary sexual organs but they wouldn’t be as developed as someone with only a Y chromosome and you would be more femine because of the presence of the second X chromosome.

Imagine you were born with only one X chromosome, X0. You would still have female primary and secondary sexual develop, however it would be substantially less than a female who developes ‘normally’.

The second story is one that many say is one of courage. “You wonder if you are making all the right decisions,” “I wish I were kind of normal. It would be so much more simple”. “I’m not doing this to be interesting. I’m doing this to live.”  Bruce Jenner

After the breakup of his marriage of 23 years he thought he could finally live freely as a women because up till now he had only done a few gender assignment procedures like electrolysis and was wearing pantyhose and bras under his suits. However, this was not enough for him to feel his true identity. Tracheal shave, taking hormones, hair on body removed, facial-feminization surgery (where they make a hairline correction, recontour the forehead, jaw and chin, augment breasts. Yet undergoing excruciating pain still went along with his gender reassignment after living as a man for 65 years.

“If I was lying on my deathbed and I had kept this secret and never ever did anything about it, I would be lying there saying, ‘You just blew your entire life,’ ” Kaitlin Jenner told a reporter at a Vanity Fair interview. “ ‘You never dealt with yourself,’ and I don’t want that to happen.”

Dick Swaab in his book called “We are our brains” talks about how males who are happy being male have a different size to the tip of their lateral ventricle (the bed nucleus of stria terminalis) then men who want to be female and equally so to women who are happy being women and women who want to be male.

Is it something more than nature that determines our identity other than nurture? Or could we say that it is just nature or nurture?



  1. Brain, C. and Collis, D. (2008). Edexcel AS psychology. Harlow: Pearson Education.
  2., (2015). Transsexual Analysis: 11. Overview and summary. [online] Available at: [Accessed 25 Sep. 2015]. Bissinger, B., Leibovitz, A. and Diehl, J. (2015). Caitlyn Jenner: The Full Story. [online] Vanity Fair. Available at: [Accessed 25 Sep. 2015].

We are our Brains: From the Womb to Alzheimer’s by Dick Swaab, review

In Dick Swaab’s book ‘We are our Brains’ he talks about how who we are is determined by nature.   How free-will is an ‘illusion’.  A fascinating concept with some great empirical evidence to back it up.  I still however believe that the body is a fantastic tool to help us see what is going on in the unconscious level.  If in fact you were born in winter and are ‘more likely to become schizophrenic’, why did you choose to be born in winter?  Did you soul choose to experience what it was like to be schizophrenic in this life time?

The Telegraph article bellow gives a fascinating summary into his explanations.

Source: We are our Brains: From the Womb to Alzheimer’s by Dick Swaab, review

In 1947 Lionel Trilling described a reductive “spectre” that, he said, “haunts our culture. People will eventually be unable to say, ‘They fell in love and married’, but will as a matter of course say, ‘Their libidinal impulses being reciprocal, they activated their individual erotic drives and integrated them within the same frame of reference’.”

Nowadays neuroscientific explanations for behaviour have largely replaced the Freudian ones Trilling was so suspicious of. We’re more likely to talk about neurons firing than libidinal impulses. But the underlying anxiety he diagnosed remains. We want to believe we are more than our brains. Are we?

Dick Swaab, a professor of neuroscience at the University of Amsterdam, doesn’t think so. In We Are Our Brains he identifies himself as a “neurocalvinist”. He thinks that everything from gender identity to sexual orientation to a propensity for schizophrenia is neurologically determined in utero. This leads him to make some counter-intuitive pronouncements. If you are born in the winter, Swaab says, you’re more likely to develop schizophrenia. Exercise is bad for you. The bigger your brain the longer you’ll live. Most antidepressants are no more effective than placebos.
Swaab argues that free will is an illusion, and that the social relativism of the Sixties and Seventies, a time when “there was a universal belief in social engineering”, was profoundly misguided. People are born bad or good, mad or sad, and there’s little we can do to change them.
More controversially, Swaab believes mothers who smoke or take drugs or are stressed during pregnancy are more likely to have gay children. Once the brain has developed environmental factors become irrelevant: “even an upbringing in a British boarding school apparently doesn’t make you more likely to be homosexual in adulthood”. Paedophilia, he suggests, is sometimes caused by a similar mechanism – exposure to higher levels of cortisol, a stress hormone, in the womb.
He defines transsexuality as a “condition” akin to body integrity disorder (the belief that one of your limbs doesn’t belong to you), and argues that anorexia is a developmental disorder completely unconnected to the fashion industry’s promotion of unrealistic female body images. “Although an eating disorder can lead to you getting a job as a stick-thin model,” he writes, “no one has ever proved that anorexic models cause a spate of eating disorders.”
Predictably, for a fan of Dawkins and Dennett, he’s down on religion. During a tour of the Vatican he drips with condescension. John Paul II greets him “in something faintly resembling Dutch”, and there are “terrible murals everywhere”. He argues that children malnourished in the womb due to their mothers fasting during Ramadan have a propensity for anti-social behaviour. (He does not mention that Islamic law discourages pregnant women from fasting.)
Swaab presents his thesis as a liberating and liberalising doctrine. If people are neurologically “programmed” to be gay or straight then condemning them for their sexual orientation is immoral, and trying to “cure” them is doomed to failure. If people are born good or bad then we should give up on the idea of incarceration as punishment.
Swaab presents himself as a taboo-breaking provocateur and much of what he says is intriguing. But his arguments are ill-served by his strident, schoolboyish contrarianism. They’re also fatally undermined by insufficient evidence. The only scientific studies he cites in We Are Our Brains are his own.Instead, most of the book is written as a series of neurological Just-So stories narrated in the manner of knock-knock jokes. “A woman who had a testosterone-producing tumor”, goes a typical report, “found that she missed it after it had been removed, because one of its side effects had been an exceptionally intense sex life.” “While in the grip of a psychosis,” Swaab writes elsewhere, “one woman believed that she could fly. She threw herself out of the window and was killed.” “One man had visions of a bright light and a figure resembling Jesus,” he says. “He turned out to have a tumor in the temporal lobe that was causing epileptic activity.” It’s all a bit vague.
On the bigger philosophical questions that attend his thesis – whether mind is identical with brain, for instance – Swaab remains mute. He defines consciousness as “an emergent characteristic generated by the joint functioning of the enormous network of nerve cells”, but tells us nothing about the relationship between this network of cells and the phenomenon we know as consciousness.
When brains go wrong, it’s clear that they have a huge impact on our behaviour. But the really interesting question, one that Swaab doesn’t begin to address, is whether we are only our brains.