How does melanin inside the eye improve vision by absorbing stray light?

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How does an anole change its color? — coloration The anole changes color in response to its stress level.

In the context of biological coloration, melanin plays a critical role in maintaining visual clarity within the vertebrate eye. It is located in the retinal epithelium, where it functions by absorbing stray light that has passed through the retina without being captured by visual pigments.1

By absorbing this excess light, melanin prevents it from scattering or reflecting within the eye, which would otherwise degrade image quality. This process ensures that light does not interfere with the primary visual signals, thereby enhancing contrast and overall visual acuity. In many invertebrates, a similar protective function is performed by ommochromes located in secondary pigment cells that surround the photoreceptors.1