Though I don’t think there is a definite answer for this but for me personally I believe that the chicken eggs comes before the chicken.
Just like how there’s no caterpillar there wouldn’t be butterfly. Or how human transform from monkey. Without egg there will be no chicken although the same thing can be said vice versus however, just like how the theory that human comes from apes (monkey) there could be possibility that chicken had also gone through some transformation of its own. In this case, egg has more possibilities because there are quite a lot of animal that produces egg including ducks, birds and more. And therefore creating a new species call “Chicken”. This is just a personal thought.
