Causes Of Homosexuality

What makes people gay?

It's a question plenty of people ask and personally I don't think it actually matters, but in the interests of science, I'm going to discuss theorized causes here. So, there are many possible causes, but few of them hold any water.

Choice
Really now? This is a common anti-gay view on the cause of homosexuality, but it really makes no sense at all. Some people believe you can choose who you love, or you can choose to stop loving someone. This is quite simply false.
But, in the interests of the pursuit of scientific knowledge, I will gladly swallow my words if, anti-gays, you can but do one thing: for the next week, become gay yourself. If it's a choice, you won't have any trouble.
Of course, then you hear hasty backtracking and several answers like 'but I don't want to be'. However, if they are unwilling/unable to 'choose' to be gay, why do they expect others to be able to?

Environmental and social influences
This theory states that upbringing can affect sexual orientation, while the theory simultaneously confuses cause and effect. There's a theory that if a boy has no strong male role model, he'll be gay, and if a girl has no strong female role model then she'll be a lesbian. Does this seem ridiculous to anyone else? The same idea could also be applied to, say, a genetic source of androgynous behaviour that affects sexual orientation. That is, genes which make a person 'non-gender conforming' to use the technical term. Not to mention, not all homosexuals have androgynous parents, and some heterosexuals do. That's not proof by itself, but the idea of social and environmental effects ignores a lot of what we know; such as the physical differences between gay and straight men and women.
Another aspect of this theory is that, if a boy hangs around with girls, when puberty starts they'll be interested in what's new to them: the same gender. However, this theory has a number of flaws: firstly, it states that, if a boy/girl isn't friends with the same gender, then later in life the repressed friendship will manifest itself as romantic attraction. This seems to be implying that love is merely heightened friendship, which means everyone is gay if they're friends with the same gender, as that's the beginning of romantic love. Not only that, but the theory ignores why people are more commonly friends with the same gender. If it was being friends with a gender that affected orientation, then you'd expect a 50/50 split, depending on who a child is friends with. instead, you have to wonder; what makes someone prefer one gender over the other in terms of friendship?
Yet another theorized social influence is sexual abuse. Apparently if a person is sexually abused as a child then they will grow up gay. Of course, this still makes no sense: how could abuse lead to love? Short answer: it can't. However, many people report having gay friends who were sexually abused. This is a minority by all standards, from what I've heard. That being said, there is a reason behind the misconception: technically, these people aren't actually gay (see 'The Biggest Misconception' post I did a while ago) as they don't love the same gender. Hear me out. The only way a person could seemingly change sexual orientation after sexual abuse is due to conditioning. The person will either associate heterosexuality with something negative, thus rejecting it, or associate homosexuality with something positive. However, this is purely in the realm of sex: pure sexual attraction, no romantic attraction. And, just to clarify, you can't be conditioned into homosexual love, simply because you need to experience the love first to become 'conditioned'. For obvious reasons, you can't experience homosexual love if you aren't romantically attracted to the same gender.

Fear
This is a slightly ridiculous idea I've seen, but it merits a mention: homosexuals are gay because they're afraid of and this reject the opposite gender. In one case, this turned into someone claiming homosexuals reject that which is different and thus are comparable to racists. My thoughts on this matter: what an idiot.
For a start, homosexuals don't reject the opposite gender: that's why we can be friends with them, that's why we are friends with them. Furthermore, if rejecting a gender is a cause of sexuality, does that mean heterosexuals reject their own gender, and thus reject themselves, by loving the opposite gender?
Of course not. I feel I can safely move on now after that ridiculous argument.

Genes
Now we're getting into controversial territory. It homosexuality in our genes?
Well, according to some people, Colberg skinny jeans make you gay, but that's a whole other topic. And a whole other spelling.
So, is there a genetic cause of homosexuality? In my view, no. That being said, I think there are genes that make a person more likely to be gay-like genes that, say, make a person more susceptible to opposite-sex hormones. For example, one study has found that gay men often have female relatives who are more fertile. Maybe it could be a gene with an extra quirk which can affect sexuality, or maybe the gene affects the ratio of hormones a person is exposed to. And that brings us on to what I believe, and what science believes, is the cause of homosexuality.

Pre-Natal Hormones
Hormones in the womb. This is without a doubt the most major, and most likely cause of homosexuality. A male foetus would be exposed to less testosterone, and more female hormones, like oestrogen, while a female foetus would be exposed to more testosterone and less oestrogen etc.
What evidence is there for this?
Well, if the hormones affect the brain in terms of orientation, then you'd expect them to affect other aspects of a person. And they do: not 100% of the time, but this is natural. A person could be exposed to different levels of hormones, or their genes could grant them a susceptibility or immunity to some hormones. Also, in cases of twins, the times both twins are gay is invariably much higher than the normal occurrence of homosexuality. It's not going to be 100% evidently, because maybe they'd each get exposed to differing levels of hormones, and there's the matter of twin-to-twin-transfusion-syndrome.
So besides that, what physical changes are there? Well, plenty, few of which can be changed after birth, and the sheer frequency of these often slight changes gives as good as irrefutable proof that the environment before birth is a deciding factor in sexual orientation.

• Finger ratios: gay men often have ring fingers at index fingers in a feminized fashion: equal lengths.
• Inner ears: lesbian women can pick up different sounds due to a more masculine inner ear structure
• Brain sizes: the hemispheres of the brain often resemble that of the opposite sex, and often certain areas can be bigger or smaller, resembling the opposite sex again.
• Chemical responses: gay men respond differently to fluoxetine, a drug used as an antidepressant
• Relative fertility: the female relatives of homosexuals are more likely to be more fertile and have more children
• Startle response: lesbians have a masculine eyeblink response after a surprising event, like a loud noise
• Odours: gay and straight people emit different underarm odours (I pity the people who tested this)
• Pheromone responses: they respond differently to sex pheromones
• Amygdala: this area of the brain is more active in homosexuals
• Left handed: lesbians and gay men are more likely to be left handed or ambidextrous
• Hair whirl: there is a much higher chance for homosexuals to have a counter-clockwise hair whirl than the general population
• Ridges: homosexuals have increased ridge depth on their left thumbs and little fingers
• Length: length of limbs and hands is generally smaller compared to height
• Words: Lesbians and gay men are often more verbally fluent
• Object location memory: gay men received higher test scores than heterosexual men in tests of this aspect
• Xq28: this is a genetic marker found in many, many homosexuals.
• Brothers: the more elder brothers a man has, the more chance he has of being gay*

So, there you have it, lots of physical and mental changes in homosexuals, many of which determined early in a pregnancy.

Conclusion

Homosexuals become gay due to pre-natal hormones. Maybe you want to hear it, maybe you don't, but you cannot dispute the facts.

*This is a footnote to the elder brothers point. This happens because a female's body sees the male foetus as an alien organism, naturally. It tries to feminize it and with each successive male child, the more adept the body becomes at achieving this. This is why around 70% of men with elder brothers are gay, and 64% or so with three. With one older brother it was just over 50%. The study was fairly limited in who it could interview, but the fact remains that the percentage goes up: as in other studies.