Sarah Nunn and Rosie Ablewhite are two, normal 29 year-old women, but they also happen to now be a researcher's dream.

They are identical twins, meaning their genes are, well, identical, and they were brought up together. This means that the circumstance for both their 'nature' (the nature of their genetic make-up) and their 'nurture' (the environment in which they were brought up, including any extraneous factors that don't relate to their genes) are pretty much exactly the same. However, Sarah is straight and Rosie is gay.

instagramView full post on Instagram

Whilst (thankfully, it's 2017 people) this isn't a big deal for most of us, but for sexual researchers it is, since Rosie and Sarah could hold the key as to where sexual orientation derives from.

Gerald Rieger and Tuesday Watts from the University of Essex have published their study of the twins in the Developmental Psychology journal. According to the Times, Nunn and Ablewhite were one of 56 twins with 'discordant sexual orientations' who provided the study with pictures of the two of them throughout their childhoods.

They looked into when and how each set of twins 'diverged.'

Unsurprisingly, the study has garnered some criticism, since the use of the photographs appears to assert that sexuality is overtly bound to gender, meaning that those who are attracted to men are effeminate or female, whilst those attracted to women are butch or masculine.

In Sarah and Rosie's pictures, however, the stereotype of a 'tomboyish' child did run true, with Sarah consistent in dresses, playing with dolls, and Rosie preferring traditionally boyish clothes and toys.

[facebook ]https://www.facebook.com/photo.php?fbid=10154709209007704&set=pb.508347703.-2207520000.1512487273.&type=3&theater[/facebook]

Speaking to the newspaper Sarah explained that she saw her sister's dress was consistent with her attitude, 'Any boyfriend instantly felt more at home with Rosie…She liked football, talked about boy things, played video games.'

When asked when Rosie herself became aware of her own sexuality she responded, 'I questioned it for so long. No offence, Sarah was really boy crazy.' They both recall an event when Rosie did not want to kiss a boy so Sarah stepped in and did it for her.

What the research did imply is that sexuality differences did assert themselves 'long before puberty', from about the age of six in girls and eight in boys.

Dr. Geiger said of the study, 'What we can do is rule out a few things now. A lot of people jump to the conclusion it must be genetics…This shows there is something early on, in the early environment, that has nothing to do with genes but can still have a tremendous effect on sexual orientation.'

His guess at this point is prenatal hormones, 'Our theory is that even though twins are identical, what happens in the womb can be quite different. They can have different nutrition, different levels of hormones.'

Whilst we don't think too much emphasis on gender roles in regards to sexuality, learning more about how we are the way we are is fascinating.

Headshot of Daisy Murray
Daisy Murray
Digital Fashion Editor

Daisy Murray is the Digital Fashion Editor at ELLE UK, spotlighting emerging designers, sustainable shopping, and celebrity style. Since joining in 2016 as an editorial intern, Daisy has run the gamut of fashion journalism - interviewing Molly Goddard backstage at London Fashion Week, investigating the power of androgynous dressing and celebrating the joys of vintage shopping.