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The kokoe poison dart frog is the third most toxic member of the Phyllobates genus — just behind the golden poison dart frog and the black-legged poison frog – when encountered in the wild. It is also the tiniest of all three, but what it lacks in size it makes up for in song. Its mating call has been called loud and bird-liike. Instead of males wrestling each other for dominance, they will simply face off and call loudly until one of them backs down. But don't be lured in by that song — these frogs store batrachotoxin in glands in their skin, which can be fatal in humans.13