Ducks fly.

Ducks have wings.

Ducks didn't always have wings, well they did because they weren't called Ducks when their wingless predecessor was about

But…at some point in time, a duck came from a creature that had no flight capabilities at all.

None whatsoever.

No partial flight, no partially flightless, no flight at all. 0%.

As much flight as a dog.

According to evolution, these completely flightless creatures had, among them, some creatures who also couldn't fly, but COULD "fly" better than the rest and thet f*cked and then the next generation also couldn't fly, at all. 0% flight from anyone. But among the 0% flight species, a couple who also had 0% flight could "fly" better than the rest.

Thus series of non-flying creatures being allowed to f*ck for 2 million years continued.

Keep in mind, within this 2 million years of flightlessness, the rest of the species WAS procreation. None of them could fly. None of them, and they all kept f*cking and living.

And over time, they began to fly somehow.

Wtf…