A newly discovered fossil in Japan dated 120 million years ago may force scientists to rewrite the evolution of flight. Preserved in 3D, it displays a bony plate near the tail that usually found in modern birds. This triangular structure supports tail feathers and promotes the evolution of shorter tails for flying. But researchers now suspect that it isn’t necessarily a flight adaptation. Earlier bird fossils from the early Cretaceous recovered from northeastern China provided an incomplete view of how birds’ distinctive adaptations projected in the avian family tree.