What came first the chicken or the egg?

At first glance, it may seem that a chicken must have come from an egg first. "Egg" is a word, that is used to describe the resulting product of procreation for many species. Based on the theory of evolution a non chicken egg at some point led to the birth of a chicken. It is important to note that an egg does not instantly turn into a chicken and there is a vast and potentially infinite spectrum of transitionary states. Somewhere in the infinite spectrum of this evolutionary transition a chicken and egg existed for a moment. One can argue that a chicken and its egg were created exactly at the same instant in time. We could further argue that the chicken and egg of yesterday is not the same chicken and egg of today.