EURASIAN ROLLER BIRD

Imagine you saw some people to whom you wanted to say hello, but as you approached, they opened their mouths—and vomited on you. You would give them a wide berth, right? In the case of young Eurasian roller birds, they have a good reason for this rude behavior: They assumed you were going to eat them. Rollers have been known to travel from Europe to central Asia, and along the way they encounter countless snakes, rats, and other predators. When the young birds hurl their orange, putrid-smelling intestinal fluid, it keeps the bad guys at bay and alerts their parents to potential trouble.