Birds flap their wings while landing even though it costs energy; a new physics model found a pigeon-sized bird would need more than twice its cruising speed and roughly 60 metres to stop without flapping

• Have you ever pondered the physics of the bird?
• In the mobile game Flappy Bird, the bird’s problem is not flying forward, it is staying airborne.
• Every tap buys a little lift, every pause lets gravity pull it down.