The Poison Dart Frog
While at first glance this frog may appear to be a colorful, 2-inch bundle of joy, it's one of the deadliest animals on earth. One golden poison dart frog contains enough venom to kill 10 grown men. They're historically used by indigenous tribes to poison their weapons—giving rise to their distinctive name. The bright colors are meant to warn predators of their toxicity, and it seems to work: Only one known snake can survive ingesting these dangerous amphibians. While you may not be in direct danger of consumption unless you're a fly, make sure not to get on this frog's bad side.