The Competitor Conversion Hypothesis of Homosexuality

The Competitor Conversion Hypothesis of Homosexuality | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article The Competitor Conversion Hypothesis of Homosexuality Douglas John Roy, Timothy Peterson This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8282787/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 6 You are reading this latest preprint version Abstract We explore a theoretical model for the evolution and persistence of a gene (G) promoting exclusive same-sex behaviour among males in a sexually reproducing species. The model presumes three preconditions: (1) evolved incest avoidance mechanisms; (2) conditional gene expression based on cues indicating the presence of close male relatives; and (3) susceptibility of rival males to conversion through contact with homosexual individuals. The rare gene conditionally expresses homosexuality in males, causing them to forgo direct reproduction and specialize in converting unrelated rivals. This competitive disruption amplifies the resulting reproductive surplus for kin (brothers) via non-linear price effects within a structured mating market. Specifically, the conversion reduces the equilibrium mating 'prices' females can charge, indirectly yielding a super-additive fitness benefit to related heterosexual males. Given its male-limited benefits and female-mediated costs, such a gene would be strongly favoured if located on the Y chromosome, with potential for counter-evolutionary pressures on the X chromosome. The model offers novel insights into the interplay between genetic architecture and reproductive economics, and suggests testable predictions for the genetic origins of homosexuality and population-level mating outcomes under natural conditions. Homosexuality Same-Sex Behaviour Spite selection Kin selection Extended Phenotype Y Chromosome Fraternal Birth Order Mating Market Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 20 May, 2026 Reviewers agreed at journal 30 Dec, 2025 Reviewers invited by journal 10 Dec, 2025 Editor assigned by journal 10 Dec, 2025 Submission checks completed at journal 10 Dec, 2025 First submitted to journal 04 Dec, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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