Many frogs and toads produce toxic and noxious substances in glands in their skin but the poison arrow frog takes this to extremes. All of the poison arrow frogs that live in the rainforests of South America are incredibly brightly coloured to warn of their danger that lurks in their tiny forms.
They produce incredibly powerful poisons. The venom of the kokoi poison arrow frog of Colombia is one of the most powerful of all known poisons, even those manufactured by the modern chemical and pharmaceutical industries. As little as 0.00001 g is capable of killing an adult man.
The local Choco Indians collect the frogs for their poison and skewer several frogs at a time on a long stick. The tribesmen hold the frogs over a fire so that the poison oozes out of their skin and then they used it to smear on the tips of their hunting arrows.