Sexuality: Nature vs Nurture

Today in class we asked the big question,

“Is is sexuality affect by nature or nurture?”

We were in groups and we had to create a presentation over a certain topic which relates to Nature vs Nurture. I was allocated to how sexuality was affected by nature and nature. Over this presentation I realised that many different people have different perspectives about a topic like this.

Our speech was,

“(Vedika) Sexuality has always been a topic that some would consider taboo. Fortunately, in our modern world, people are becoming a lot more accepting, and we are making big progress towards equality for all. However, to study the psychology behind sexuality is something that is very complex, because at this moment we haven’t found one ‘right’ answer to the big question we are focusing on, “Nature vs. Nurture”. So how do we define how sexuality fits into these categories, and is sexuality really ‘caused’ by either nature or nurture, or simply both?

(Issy) According to nature, many studies have found that sexuality is determined by genetics and your DNA sequences. In 1940, researchers concluded that a ‘homosexual gene’ must exist, so as the investigations commenced, finally in 2014 scientists confirmed that there is a hereditary gene that is linked with homosexuality. This is easy enough to understand right? Yes, and no. This gene was found to be passed down through generations, however the way it is acquired and transferred is something more complex, called epigenetics. Epigenetics are related to the influence of external factors to your gene changes. These include aspects such as medicine, chemicals, and even the pesticides found on the food you eat. Epi-marks (epigenetic marks) are usually erased between generations, but in some cases they remain, therefore possibly causing homosexuality. As well as this, some other factors include testosterone levels changing the sexuality of a male. Also, interestingly, Dr Swaab (the same doctor from the documentary we watched) found an area of the brain in a post-mortem examination that a part of the brain – a small part of the hypothalamus, the suprachiasmatic nucleus – was 1.7x the size in homosexual males than in straight males. As for bisexuality, there are very few to no reliable studies on it – as the brain would have to show behaviours of both being attracted to the same gender as well as opposite, rendering it difficult to study. 

(Jyun)While most evidence points to sexuality being natural, there are multiple studies that suggest that it could also be a cause of upbringing.

(Jyun)Most social psychologists see childhood factors as the largest contributing elements to homosexuality. Often they examine play patterns, early friendship interactions and relations, differences in parental behaviour toward male and female children, and the part that gender roles play in the household. 

(Jyun)Undoubtedly, some elements of both nature and nurture cannot be confirmed, especially in this topic. Different aspects affect different people, hence we cannot make a general statement for the majority of people. For example, while biology might be setting the base for sexuality, someone’s upbringing could completely change the attitudes and characteristics of that person. Hence, anyone can be impacted from a number of different  factors.

(me) There are many studies that related to this topic which are very interesting and help us have an insight into the conclusions that have been made. A study conducted by J. Michael Bailey and Richard Pillard researched the homosexuality similarities between identical twins, non-identical twins and non-related adopted brothers. They found that 52% of identical twins were both self-identified homosexuals, 22% of non-identical twins were gay, and only 5% of non-related adopted brothers were so. This evidence, repeated and found to be true a second time, showed the biological connection that the more closely genetically linked a pair is, the more likely they both are to exhibit gay or straight tendencies. Later experimenters found similar evidence in females. Gerulf Rieger also conducted a study that theorised a rule named the ‘Older Brother Rule’. It explains that the more older brothers a man has, the better chances there are of being gay. In fact, each older brother can increase the chances by 1/3. There is no similar effect with women. They have theoretical evidence to suggest that this happens in the womb. But even more weirdly – this only applies to boys that are right handed. Left handed boys have the same chances as anyone else on this planet and this ‘older brother’ factor doesn’t play in. “

After researching about this topic, I realised that I believe with the Nurture side. I believe that is it because of the way someone is brought up why they change their sexuality.  I feel like this was a really good opportunity to understand a topic like this since we don’t really talk about this subject. This presentation gave us a chance to openly give our opinions and see the different viewpoints of other people including classmates, researchers and friends. I honestly feel like we should discuss these types of topics like this open our minds as that is the sole purpose of Global Perspectives.