How Wings Got Useful

How do half-formed wings help an animal that cannot yet fly? One clue comes from living birds. Chukar partridge chicks, long before they can take off, flap their stubby wings to scramble up steep slopes and even tree trunks — the flapping presses their feet into the surface for grip. It hints that early dinosaur wings paid off as traction and balance first, with full powered flight arriving only later, once the design was good enough.