The deadly toxin with no known antidote
Poison dart frogs have evolved to produce highly poisonous skin secretions because many of their predators, such as snakes and spiders, have evolved to develop a resistance to milder toxins.
Their young are a brownish colour and their poison has not developed yet – these animals accumulate their poison as they reach adulthood. In fact, one adult frog contains sufficient poison in its skin to kill at least ten adult humans.
The poison is absorbed directly through the skin and is easily transmitted. Its potency and the ease with which it is administered make it even more deadly. It attacks the nervous system and quickly leads to heart failure. A single genetic mutation in these frogs means they are entirely immune to their own toxins.