They are one of evolution's most useful and prevalent inventions. Ninety five percent of living species are equipped with eyes and they exist in many different forms. Learn how the ancestors of jellyfish may have been the first to evolve light-sensitive cells. Discover how dinosaur's evolved eyes that helped them become successful hunters. Finally, learn how primates evolved unique adaptations to their eyes that allowed them to better exploit their new habitat, and how the ability to see colors helped them find food.