Who came first ? chicken or egg??!

Who came first ? chicken or egg??

I actually think I figured out the answer and I will give a plausible explanation. I have spent many hours and days(lol yea I have no life) contemplating which came first and I figured out the answer. My theory is that the chicken came first. I figured out my answer from a religious perspective, b/c first God created Adam( a grown man and not a baby) then he created Eve(a grown woman) and then the animals. So thus he created the chicken and then the chicken reproduced and created the egg. It is a plausible explanation and my theory. It's sad that I actually thought about that for so long lol. I hope I was of some assisant lol.