Abstract
Previous research has examined handedness and birth order to inform sexual orientation and gender identity/role expression development; however, sexual orientation and gender identity/role expression have rarely been disentangled to provide a more nuanced perspective. In Thailand, we investigated sexual orientation and gender identity simultaneously via comparison of 282 heterosexual men, 201 gay men, and 178 sao praphet song—i.e., androphilic, markedly feminine males recognized as a “third” gender. Handedness was examined as: extremely left-handed, moderately left-handed, ambidextrous, moderately right-handed, or extremely right-handed. Birth order was examined as numbers of older and younger brothers and sisters, by using Berglin’s, fraternal, and sororal indices, and by examining the older brother odds ratio and sibling sex ratio. Compared with heterosexual men, gay men and sao praphet song were more likely to be extremely right-handed. Sao praphet song were also more likely to be extremely left-handed than heterosexual and gay men. Heterosexual men and sao praphet song had later sororal birth order compared with the expected Thai population value, suggesting stopping rules influenced when probands’ mothers ceased having children. These findings provide new insights and replicate previous findings in a non-Western sample. Regarding handedness, in males, mechanisms related to extreme right-handedness likely influence the development of androphilia, whereas mechanisms related to both extreme right- and extreme left-handedness likely explain the combination of androphilia and feminine gender identity/role expression. Regarding birth order, similar to the conclusions of some prior research, stopping rules pose a challenge for testing the fraternal birth order effect.
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Notes
There is presently no universally accepted nomenclature that can be applied to satisfactorily capture all of this variability in sexual orientation and gender identity/role expression simultaneously. Thus, our use of terminology follows common conventions in the anthropological literature on sexual orientation and transgender or third gender identity (e.g., Sinnott, 2004; VanderLaan, Ren, & Vasey, 2013b), and is also in line with international guidelines suggested by those in the field of transgender health (Bouman et al., 2017). When describing specific individuals, samples, or groups of individuals who can be characterized accurately and appropriately by a particular identity term, then that term is used. When describing patterns that appear to apply across several groups that are heterogeneous with respect to identity and, thus, no common identity term can be employed accurately, then the following phenotypic descriptors are used: (1) sexual orientation is denoted using the terms gynephilia (i.e., sexual attraction to adult females) and androphilia (i.e., sexual attraction to adult males); (2) male and female are employed in the biological, not sociocultural, sense to describe individuals according to the observable primary sex characteristics (i.e., genitals) with which they were presumably born; (3) transgender describes individuals whose gender identity aligns with, or closely aligns to, that of the other sex whereas cisgender describes individuals whose gender identity aligns with that of the same sex; and (4) masculine and feminine denote gender expression that is male-stereotyped and female-stereotyped, respectively, relative to the prevailing norms of the particular culture under consideration. These terms are used only as descriptors and are not intended to take the place of identity terms that could be more aptly applied to specific individuals or groups of people.
The term kathoey has often been used in prior literature to describe feminine third gender Thai males (e.g., Totman, 2003) and some Thai individuals identify themselves using this term (Winter, 2006a, 2013); however, this term technically can be applied to multiple third gender identity categories (Sinnott, 2004) and, based on reports from Thai informants, can often carry a pejorative connotation in contemporary Thai society. As such, the term sao praphet song, an alternate term that is also often used (Winter, 2006a, 2013) that does not carry a pejorative connotation, has been used here instead.
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Acknowledgements
Special thanks to Aunyawee Chaiwatpornpat, without whom this research would not have been possible, and the Khankham family. Thank you also to Itsara Boonyarit, Kamonphorn Chaisabai, Louis Gooren, Phobphat Khankham, Phuntira Kunta, Chananart Putti, Sayan Putti, Suwit Saekho, Preedeya Shisornjai, Rattanakorn Sitthisapphokhin, Tanapong Sungkaew, Lindsey Thurston, and the staff at Baan Ruk Rean and at the Runway Academy. MNS was funded by a Brain Canada Postdoctoral Fellowship. This research was funded by a Natural Sciences and Engineering Research Council (NSERC) of Canada Discovery Grant awarded to DPV.
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Skorska, M.N., Coome, L.A., Saokhieo, P. et al. Handedness and Birth Order Among Heterosexual Men, Gay Men, and Sao Praphet Song in Northern Thailand. Arch Sex Behav 49, 2431–2448 (2020). https://doi.org/10.1007/s10508-020-01774-z
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DOI: https://doi.org/10.1007/s10508-020-01774-z