Rhinos are almost blind. They haven’t had to develop keen eyesight in their evolutionary history because no one was tough enough to compete with their size, strength, and powerful defensive armor. Until, that is, humans started poaching these animals for their horns. Since they can’t see humans creeping up on them, a bird plays the role of look-out and warns the rhino of danger. The red-billed oxpecker feeds off the ticks and lice on the rhino hide and in return gives a sharp call that alerts the rhino to battle stations.