Gender Identity Service, Child, Youth and Family Services, Intergenerational Wellness Centre, Centre for Addiction and Mental Health, 80 Workman Way, Toronto, ON, M6J 1H4, Canada,
Arch Sex Behav. 2014 Jul;43(5):1009-22. doi: 10.1007/s10508-014-0288-0. Epub 2014 Mar 12.
The kin selection hypothesis posits that male androphilia (i.e., sexual attraction to males), although detrimental to reproduction (i.e., direct fitness), has persisted and evolved because androphilic males compensate by increasing their indirect fitness via increased investment in kin. In previous studies, Samoan androphilic males (known locally as fa'afafine) reported elevated avuncular (i.e., uncle-like) tendencies compared to Samoan gynephilic (i.e., sexually attracted to females) men. Their avuncular tendencies were also greater than the materteral (i.e., aunt-like) tendencies of androphilic women. The present study examined whether the avuncular cognition of fa'afafine was enhanced for maximizing indirect fitness. To do so, it examined whether fa'afafine had a stronger propensity than Samoan gynephilic men and androphilic women to invest in kin categories that would result in more reliable and substantive increases in indirect fitness (i.e., young, female kin) in hypothetical investment scenarios. In a forced-choice paradigm, although all individuals showed some degree of bias to invest in adaptive kin categories during non-frivolous investment contexts in which the consequences of investment were relatively non-trivial, fa'afafine showed greater adherence to the predicted pattern. In addition, shifting the context from frivolous investments, in which the consequences of investment were relatively trivial, to non-frivolous investments prompted fa'afafine to exhibit an enhanced preference, relative to Samoan gynephilic men and androphilic women, to invest in adaptive kin categories. These findings were consistent with the kin selection hypothesis and suggest that, although all individuals exhibit cognitive biases for increasing indirect fitness, the avuncular cognition of androphilic males has undergone selective enhancement to maximize the accrual of indirect fitness via kin-directed altruism.
亲属选择假说认为，男性的同性恋倾向（即对男性的性吸引）尽管对繁殖（即直接适合度）有害，但仍得以持续和进化，是因为同性恋男性通过增加对亲属的投资来增加其间接适合度，从而得到补偿。在以前的研究中，萨摩亚同性恋男性（当地人称为“fa'afafine”）与萨摩亚异性恋男性（即对女性有性吸引力）相比，报告称其叔伯般（即类似叔叔的）倾向有所增加。他们的叔伯倾向也比同性恋女性的母性（即类似阿姨的）倾向更大。本研究考察了 fa'afafine 的叔伯认知是否增强了以最大化间接适合度。为此，它考察了 fa'afafine 是否比萨摩亚异性恋男性和同性恋女性更倾向于投资于那些会导致间接适合度更可靠和实质性增加的亲属类别（即年轻的女性亲属），在假设的投资情景中。在强制选择范式中，尽管所有个体在非琐碎投资情境中，即在投资后果相对非琐碎的情况下，都表现出某种程度的投资适应性亲属类别的偏见，但 fa'afafine 表现出更强的坚持预测模式的倾向。此外，将情境从琐碎的投资（其中投资的后果相对微不足道）转换为非琐碎的投资，促使 fa'afafine 表现出相对于萨摩亚异性恋男性和同性恋女性更强的偏好，以投资于适应性亲属类别。这些发现与亲属选择假说一致，并表明，尽管所有个体都表现出增加间接适合度的认知偏见，但同性恋男性的叔伯认知已经经历了选择性增强，以通过亲属导向的利他主义最大化间接适合度的积累。
