How do birds wings work - how do they fly?

Answers:
they flap them ;)

---

the wings help to overcome the gravity, so they fly afloat in the air

---

no idea

---

birds have lungs which are like air sacks enabling it to float and light hollow bones also help it to fly.
their wings are very feathery and help the bird to push air in order to navigate itself

---

?

---

There are four forces which makes birds to fly.
Four forces (thrust and drag, lift and weight) helps them to fly.
Same for airplanes too.

---

The fundamentals of bird flight are similar to those of aircraft. Lift force is produced by the action of air flow on the wing, which is an airfoil/aerofoil ...Flapping involves two stages: the down-stroke, which provides the majority of the thrust, and the up-stroke, which can also (depending on the bird's wings) provide some upward force. At each up-stroke the wing is slightly folded inwards to reduce upward resistance. Birds change the angle of attack between the up-stroke and the down-stroke of their wings.

---

It's very complex - it involves different types of feathers for different uses, air currents and gravity. The whole of a bird's anatomy is specifically designed to allow them the power of flight, not just their wings. I think this will explain it best:
http://en.wikipedia.org/wiki/bird_flight...

Chalice