1.   But why would such a creature have developed feathers in the first place, if it was incapable of flight?

2.   Several hundred million years ago, fishlike creatures developed rudimentary fingers and toes, which helped them drag their way onto dry terrain.

3.   If the first microscopic creatures developed under such conditions, then life is tough indeed.

4.   The atmosphere filters some out, and earthbound creatures have developed a general tolerance to those that get through.

5.   Traditional theory holds that creatures developed primitive arms, legs, fingers and toes during the evolution from sea beasts to land-roamers.