Hormesis and the Golden Ratio: Toward a Universal Estimator of Adaptive Capacity

Hormesis represents a universal feature of biological plasticity across species and environmental contaminants. Here I propose that the maximum stimulatory peak converges upon the golden ratio (φ = 1.618), representing a 61.8% increase above baseline, a value embedded within the empirically observed 30%-60% range but offering mathematical precision for a unifying quantitative reference. I further hypothesize that the internal architecture of the hormetic zone may follow the complementary proportion of φ (0.382), with the rising phase occupying the smaller fraction (steep ascent) and the falling phase the larger fraction (gradual decline), reflecting natural selection for rapid threat response followed by sustained benefit. This framework positions the golden ratio as a potential evolutionary optimum, a Pareto-efficient allocation where further investment yields diminishing returns. While the dose-width to toxicity remains variable and context-dependent, the peak magnitude may reveal a fundamental constraint on the adaptive capacity of life. Testing this hypothesis requires systematic meta-analysis of existing databases and targeted experiments manipulating resource availability, genetic background, and evolutionary history.