Dr. Marshall Westwood fell ill after eating pufferfish in Indonesia, experiencing numbness and paralysis. He was diagnosed with tetrodotoxin poisoning from the pufferfish. Later, while birdwatching in Papua New Guinea, Westwood's fingers and lips went numb after handling a pitohui bird. Westwood discovered the bird produces homobatrachotoxin, a toxin similar to tetrodotoxin that acts on voltage-gated sodium channels. Westwood asked colleagues to help determine how this new toxin works.