Last week, the Academy of Science of South Africa released a comprehensive review of the research on sexual orientation, hammering home that the grand diversity of human sexuality isn't something people really choose -- it's all biology.
The study, completed in conjunction with the Uganda National Academy of Sciences, examined over 150 recent research papers testing the effects of social and biological factors on sexual orientation. They used the results to determine whether the public health arguments some African officials put forward for criminalizing homosexuality had a scientific leg to stand on. The answer was no:
- They found no evidence that the relationship between parent and child can affect the child's adult sexual orientation, even though parenting style and early childhood experience does have strong effects on adult intelligence and later educational achievement.
- They found no evidence that sexual orientation could be "transmitted" through social interactions with LGBTI people or changed by peer pressure, refuting the argument that teenagers are "recruited" into same-sex relationships.
- They found no evidence that sexual orientation can be changed by therapy, refuting the argument that people with same-sex orientations should be given corrective therapy.
They also found that many varieties of biological evidence support the idea that sexual orientation is innate, including studies of genetic linkage, epigenetics, twin siblings, and neuroanatomy. These studies support the idea that sexual orientation is produced from a complex interaction of each individual's genes and the uterine environment, and firmly refute the idea that a same-sex orientation is "unnatural".
From the study:
Proponents of new laws against same-sex relationships often argue that the key difference between discriminating on the basis of sex or race, and discriminating on the basis of sexual orientation, is that same-sex orientation is chosen rather than biological (or, alternatively, when this argument is debunked, that same-sex orientation is forced onto people by homosexual 'recruiters', usually through forced molestation). People making these arguments usually also believe that same-sex attraction is a pathology and an illness of some kind, i.e. both that it can be 'cured' and that it is inferior to heterosexuality and threatening to heterosexuality.
...these positions have no scientific validity. Sexual orientation is akin to race and biological sex in that, for most people, heterosexual or otherwise, sexual orientation is not a choice in any meaningful sense of the word.
What's more, the study finds that laws that criminalise same-sex orientations do not -- as their supporters claim -- improve public health.
From the study:
There is clear evidence that more repressive environments increase minority stress and impact negatively on LGBTI health. This has a direct impact on the general population's health, particularly in terms of HIV and AIDS, TB and other STI reduction campaigns. There are no known positive impacts on public health because criminalisation cannot stop people from feeling same-sex attractions and expressing same-sex orientations. It merely makes it harder and more stressful to be same-sex orientated and makes LGBTI individuals less likely to access health care and more likely to suffer ill-health. This causes reductions in broader social cohesion and broader social stress, as well as enhancing the transmission of infectious diseases, including HIV.
Read the entire study from the Academy of Science of South Africa. It may not lead to the repeal of unfair anti-gay legislation tomorrow, but it does makes it clear that those laws don't have anything to do with science.