You may have thought humans were the only primates with blue eyes, but the Sclater's lemur begs to differ. Found in Madagascar, males and females often have different-color fur, but both can have blue eyes.
The goat's rectangular pupil can be explained by a simple evolutionary fact: They're the hunted, not the hunter. This pupil shape increases the goat's depth perception as well as his peripheral vision - all the better to spot predators with.
You've heard of eyes in the back of your head. Well, the barreleye fish has eyes on top of his head. The large green peepers are visible through his see-through head and can move upward to sense potential danger as well as look straight ahead.
The eyes of an ostrich are the very definition of big and beautiful. These brown beauties can measure 2 inches across, surpassing the eye diameter of giraffes, elephants, and all other land animals for that matter.
These fearless predators feast on scorpions, spiders and such, and can be found in deserts throughout Pakistan, Iran and Iraq. Unlike most geckos, these guys can blink. They clean their eyes by licking them.
The most surprising part about the scallop's eyes is that they exist at all! These eyes are a security system, functioning as light and motion detectors that warn the scallop when a predator is approaching.
Each of the tarsier's eyes is the same size as his brain - they have the largest eye-to-body ratio of any mammal. These large peepers allow him to catch prey and avoid predators during his nighttime excursions in his native forests of Borneo, Sumatra and Belitung.