The chicken and the egg

In my previous post, I referred to the "chicken and egg" problem: Who came first?

Marketing is full of chicken and egg problems (especially when it comes to the diffusion of innovation). I had used this metaphor for a long time and but did not really know the answer to the question.

Finally, I decided to e-mail my old biology professor from college. The answer: The egg came first. But this answer just postpones the question. The problem is that the egg can be traced in the evolutionary chain back to amphibian reptiles. So, what came first, the egg or the reptile? Then again, the reptile's ancestor likely came before either of the two.