Description: Currently you are watching Twins with different sexualities porn video. You can find more videos like Twins with different sexualities below in the related videos section. The relationship between biology and sexual orientation is a subject of research. While scientists do not know the exact cause of sexual orientation , they theorize that a combination of genetic, hormonal, and social factors determine it. Biological theories for explaining the causes of sexual orientation are favored by scientists  and involve a complex interplay of genetic factors, the early uterine environment and brain structure. A number of twin studies have attempted to compare the relative importance of genetics and environment in the determination of sexual orientation. Self reported zygosity , sexual attraction, fantasy and behaviours were assessed by questionnaire and zygosity was serologically checked when in doubt. Other researchers support biological causes for both men and women's sexual orientation. To understand why this isn't convincing, we have to ask the question: how can twins have different sexual orientations, or in fact any other.
Added: 26.03.2019 at 18:07
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