Why natural selection have not acted against gay guys?

It is still controversial whether one’s sexual attraction is defined by nature or nurture. Since American Psychiatric Association eliminated homosexuality from their list of Psychological Disorders and in 1975, it is the nature which is winning over nurture. So if we could accept it and make one more step further to announce it is in your genes whether you’ll be gay or straight, we will reach the ultimate question. Gays contribution in generating the next generation used to be minimum if at all existing. There are numerous example of homosexual individuals, writers, artists and scientists, who left this world without contributing their DNA to the next generation. They have just recently benefited from the scientific advancements, like IVF, to assist passing their genes on.

samoa

Putting this all in an evolutionary perception, why these androphilic and gynephilic fellows, colloquially known as gay and lesbian, have not been selected against in natural selection? Why there should be a gene or two making you gay when it will make you less prone to have an offspring to pass this gene one? Is there a gene acting against evolution rules?

To find the answer, Canadian researchers at University of Lethbridge have looked at androphilic men in ancient hunter-gatherer communities in Polynesian island nation of Samoa. In this pro-transgender society, gay guys are considered an extra pair of hands to support their families. It is by helping their families that they can ensure the family line is passed. So this gene is acting on group survival rather than individual transmission of the genes to the next generation. This phenomenon has been well studies in social insects, like bees. While the worker bees will not have any opportunity to pass their genes to the next generation, by gathering honey and taking care of the young, they will make the whole group stronger and more robust to survive.

So it is kin selection which plays an important part in maintaining the genes responsible for male androphilia in these societies. The study also include a few cross society comparison and shows existence of the same pattern of kin support among androphilic males across “bilateral descent” societies, which refers to societies in which the families of both one’s father and mother are equally important for emotional, social, spiritual and political support.

Hence, if transgendered males are accepted in their families and the society, they will be an asset like everyone else in the society.

Ref. Doug P. VanderLaan, Zhiyuan Ren, Paul L. Vasey, ‘Male Androphilia in the Ancestral Environment’, Human Nature  October 2013 DOI: 10.1007/s12110-013-9182-z

Picture above is shot by Stephanie Rabemiafara, from Trekearth’s archive.

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