Certain species of frogs in the genus Phyllobates have a powerful defensive adaptation—their skin can secrete a milky fluid that contains an extremely toxic compound called batrachotoxin (BTX). These frogs, which are found in Colombia, are known as poison dart frogs because some indigenous Colombian hunters coat the tips of their blowgun darts with the frogs' skin secretions. An animal hit by one of these darts dies quickly. What is the mechanism of action of BTX?Although BTX is a powerful antipredator poison, one snake species in Colombia eats poison dart frogs. Suggest a hypothesis that might explain how the snake is resistant to the toxin.