Department of Social Sciences, University of Nicosia, 46 Makedonitissas Ave., 1700, Nicosia, Cyprus.
Arch Sex Behav. 2022 May;51(4):1857-1864. doi: 10.1007/s10508-021-02199-y. Epub 2022 Apr 4.
Same-sex attraction is associated with a direct reproductive cost, i.e., a reduced number of biological children. The current study aimed to assess this cost for different forms of sexual attraction (i.e., only attracted to opposite sex, mostly attracted to opposite sex, equally attracted to both sexes, mostly attracted to same-sex, only attracted to same-sex), using two large nationally representative datasets (N = 15,208) from the USA. The results indicated that same-sex attraction was associated with substantial loss in direct reproductive output. More specifically, significant differences between the different types of same-sex attraction were found: Exclusive and mostly homosexual orientation identities were associated with the highest direct reproductive cost, while mostly attracted to opposite sex orientation and bisexuality identities were associated with lower direct reproductive costs. In addition, bisexual women did not differ significantly from exclusively heterosexual women in terms of their reproductive output. The implications of these findings for the evolutionary origins of same-sex attraction are further discussed.
同性吸引与直接生殖成本有关，即生育的生物学后代数量减少。本研究旨在使用来自美国的两个大型全国代表性数据集（N=15208）评估不同形式的性吸引（即仅对异性有吸引力、主要对异性有吸引力、对两性同等吸引力、主要对同性有吸引力、仅对同性有吸引力）的这种成本。结果表明，同性吸引与直接生殖产出的大量损失有关。更具体地说，不同类型的同性吸引之间存在显著差异：排他性和主要同性恋取向身份与最高的直接生殖成本相关，而主要对异性吸引和双性恋身份与较低的直接生殖成本相关。此外，双性恋女性的生殖产出与完全异性恋女性没有显著差异。进一步讨论了这些发现对同性吸引进化起源的影响。
