This particular question is one of the most debatable question in history and it's actually a science question.
Let me ask the community though, which do you think came first, the chicken or the egg?
The scientists now believe that the egg came first before the chicken came.
The reason they say the egg acme first is because is the process of evolution, animals change very slowly over time. It's not something you can see with your eye happening. Just like how your little sister or brother grows into an adult right before your eyes but you don't see how the changed, it just happened but evolution takes way longer than that.
They said that a very long time ago, there were birds that were not chickens but were very similar to chickens. One of these birds laid an egg and due to some tiny changes in its DNA, the chick that hatched from it became what we now call a chicken. So the first true chicken came from an egg laid by a bird that was almost like a chicken but not. We already know that animals including ourselves develop new traits over many generations as a way to evolve to changing conditions, that's the reason the slight DNA change happened for the first chicken to come.
So that explains the question, the egg came before the chicken.
