Post-flight feast: Study suggests reindeer vision evolved to spot favorite food

Researchers from Dartmouth College and the University of St. Andrews report that reindeer eyes may have evolved to easily spot their preferred meal, reindeer moss. Reindeer eyes have mirror-like tissue that changes color from greenish gold in the summer to vivid blue in the winter, amplifying the low light of polar winter. Unlike other mammals, reindeer can see light in the ultraviolet spectrum. Reindeer moss absorbs UV light, making it stand out as dark patches to the animals. This allows reindeer to conserve energy by efficiently finding food.