Why Anti-Trans Arguments May Be Anti-Science: A Structural Explanation via Overdominance Equilibrium

This preprint presents a minimal evolutionary model demonstrating how transgender identities can persist as a stable minority under the classical overdominance (heterozygote advantage) mechanism. By modeling a simple genotype-fitness structure, the paper shows that when heterozygous individuals exhibit higher average fitness than either homozygous type, population-level selection naturally stabilizes a small proportion of full-expression phenotypes (e.g., transgender identity), alongside a broader non-binary or ambiguous middle zone. The model has three key implications: The existence of transgender and non-binary individuals is not paradoxical from a biological standpoint, but a mathematically expected outcome. Attempts to eliminate such expressions are structurally misguided, akin to erasing a system’s stable attractor. The lack of engagement with such basic biological reasoning in modern gender discourse reflects a deeper theoretical misalignment. This work argues that denying the structural plausibility of transgender existence constitutes a form of anti-scientific reasoning. The paper aims to reframe the discourse surrounding gender diversity using tools from population genetics and evolutionary stability theory.