Rudolph doesn't go Snowblind

Polar explorers and local populations such as Inuit sometimes experience a condition known as snow blindness. This is also known as ultraviolet keratitis, a painful eye condition caused by prolonged exposure to ultraviolet rays. Ultraviolet radiation is well known for being dangerous to humans, because of the associated risk of melanoma. This risk gains with latitude, because of the thinner ozone layer, that is less effective in blocking those rays, explaining the high rate of snowblindness.

The Inuit, to help prevent snow blindness, carved snow goggles from reindeer antlers. Those goggles were curved to fit the user's face, protecting the eye from UV radiation. Anyhow this solution wasn't possible for reindeers, so biologists started wondering how Arctic mammals adapted to survive in those conditions. It resulted that they did not only adapted to tolerate those conditions but also used  them as an evolutionary advance becoming able to perceive UV light. This brought them many advantages. In fact their primary food, lichens, and fur of their predator both adsorbed UV light and made them stand out the snowy landscape, that reflects light.

A deep understanding of how reindeer prevented  UV rays from being dangerous  could be useful to treat loss of vision with age. In fact the loss of central photoreceptors over the course of life could be related to light exposure. Understanding how and why Arctic mammals adapted to those extreme conditions could be fundamental to prevent and treat loss of vision with age.