Possibly. The trees-down (or "arboreal") hypothesis has been around for many years, says evolutionary biologist Richard O. Prum of Yale University. Researchers guessed that the scales of tree-dwelling Triassic reptiles elongated into feathers, which helped them leap away from predators. Once the proto-birds could glide, they were en route to avian flight. "It was like one big, crazy hairball of ideas all stuck together," Prum says.