The causes of sexual orientation are likely complex and influenced by multiple factors. We advocate incorporating a broader cultural perspective into evolutionary and genetic studies to account for differences in how sexual orientation is experienced, expressed, and understood in both humans and non-human animals.
The data currently available to scientists studying sexual orientation are impressive in their scope, complexity, and specificity. For example, in humans, sequenced genomes and surveys of hundreds of thousands of individuals are available, as are decades of observations from brain scans, eye-tracking, recordings of genital arousal, and daily digital diaries. If there were a single, simple explanation for differences in sexual orientation, it would likely have been discovered by now. The fact that this has not been the case suggests that basic assumptions about what causes variation in sexual orientation (e.g., occurrence, function, representation, genetic basis, stability, and gender) need to be reexamined. It is likely that sexual orientation is shaped by a complex interaction of various factors. In this context, we will focus on the causes that contribute to variations in the phenotype. Furthermore, a relatively unexplored area of research concerns the reasons for and consequences of aversion toward same-sex sexuality, at both the individual and societal levels. Here, we discuss these historical hypotheses, the research that has overcome them, and possible directions for the future.
Human evolutionary biology, by overturning the traditional (but arbitrary) barriers between ...More