"and now the conclusion: the chicken and the egg are the same thing!"

No, not really. They are two different "things" (chicken and egg), similar in that they are composed of the same "thing" (energy/matter) but due to the varying composition we can accurately call them two different things.

Unless you're working off a monistic view of the universe, in which case I should say they are two different representations of the same thing, but, really, at this point, we are just struggling with the semantics of metaphysics, a struggle that has lead some philosophers to deny that metaphysical inquiries have any value past the practice of logical thought.

"If there is a god then the chicken came first.
The egg needs the chicken to nurse it and sit on it for warmth."

Not necessarily. First, the egg only requires protection and warmth, something that could be provided by a chicken-like, but not necessarily chicken, creature. Further, if there is a God, the evolutionary process is not automatically disregarded as God and evolution do not necessarily conflict (only some understandings of God conflict with evolution, silly understandings that defy logic).