Beware of Deadly Birds with Nerve Agent Feathers

Two bird species in Papua New Guinea, the regent whistler and rufous-naped bellbird, have been found to store a potent neurotoxin called batrachotoxin in their feathers, which can cause muscle cramps and cardiac failure. Researchers have discovered how these birds avoid making themselves sick from the poison. The toxin is suspected to be a deterrent for predators or parasites. The birds have mutations in a protein that forms one of the sodium channels, which is an example of convergent evolution. The spread of poisonous organisms throughout an ecosystem is a slow-moving but fierce evolutionary battle.