Microstructure and transcriptomics reveal rapid light-induced visual plasticity in the non-obligate cave dweller Oreolalax rhodostigmatus (Megophryidae, Anura)

Prolonged light exposure induces significant structural, ultrastructural, and molecular adaptations in the visual organs of O. rhodostigmatus tadpoles, including retinal layer thickening, photoreceptor regeneration, and upregulation of phototransduction pathways. The downregulation of s26 and absence of mutations common in obligate cavefish suggest retained latent pathways enabling reversible plasticity, rather than irreversible degeneration. This adaptive plasticity allows non-obligate cave dwellers to balance energy conservation in darkness with functional vision restoration upon light exposure, representing a distinct evolutionary strategy compared to obligate cave species.