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arXiv · 2607.20513

Magnetosensitivity of amphibian morphological pigmentation is light- and eye-dependent and consistent with the radical pair mechanism

Hadi Zadeh-Haghighi·Gabriel E. Bertolesi·Sarah McFarlane·Christoph Simon
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Abstract

Weak magnetic fields influence a wide range of biological processes, yet the underlying mechanisms are poorly understood. The radical pair mechanism (RPM), which involves quantum spin dynamics, is a leading hypothesis. Here we show that weak magnetic fields modulate morphological pigmentation -- specifically, the number of perioptic melanophores -- in Xenopus laevis tadpoles in a field-strength-dependent manner. The response is light- and eye-dependent. The observed field-strength dependence is quantitatively consistent with a radical pair model. These properties are reminiscent of the light-dependent magnetoreception that is thought to operate in migratory birds, and establish amphibian pigmentation as a tractable vertebrate system for the study of radical-pair quantum biology.

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Hadi Zadeh-Haghighi, Gabriel E. Bertolesi, Sarah McFarlane, Christoph Simon. 2026-07-07. Magnetosensitivity of amphibian morphological pigmentation is light- and eye-dependent and consistent with the radical pair mechanism. https://arxiv.org/abs/2607.20513

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