One mystery of birds’ flight is solved! The elegance of birds’ flight, their seemingly effortless aerial turns and the softness of their landing, have been envied by many people. From countless observations, it has been known that the birds use a small group of feathers, called “the alula”, a thumb-like structure that is present at the bend of the wing, in slow and steep flight such as landing. Why do they use it? How the tiny feathers can help them land softly? … [Read More]