How did the chicken come about though? If we define chicken as exactly what we have today, that means it must have been born in a hard shelled egg. I'm assumin

How did the chicken come about though? If we define chicken as exactly what we have today, that means it must have been born in a hard shelled egg. I'm assuming that evolution would happen slowly over time, the creature that ended up becoming the chicken would have had to already been laying eggs. The egg laying feature would need to already be present for it to be our modern day preciously defined chicken. The egg had to have come first