Overview:The Kiwi is a bird that has thrown out the rulebook of bird biology. It doesn’t fly, lives in the dark, and resembles a mammal more than anything bird-like. Since the introduction of rodents, this national symbol has faced an existential threat. But how did a flightless bird find itself on islands in the middle of the ocean? From the rainforests of Australia to ancient caves in one of New Zealand’s wildest places, we discover how the secret to the kiwi’s success may have become its gravest threat.