100% agree. I was surprised that the population of people who would take such a quiz are actually 50/50 on this! I agree that the best basis for chickenhood is

100% agree. I was surprised that the population of people who would take such a quiz are actually 50/50 on this! I agree that the best basis for chickenhood is the genetic one you present, which implies that the egg came first. Further, I think that the second-best argument is that the first chicken was the first animal to be called "chicken" by someone. In that case, that first chicken came from an egg, which was laid by something which was never called a chicken, hence not a chicken. The egg still came first. Writing this now, it occurs that perhaps almost any satisfying definition of chicken implies that the egg came first. If you can define what a chicken is and you assume that chickens have not always existed, then it follows that there must have been a first chicken. If you assume that the first chicken hatched from an egg (if not, your definition of chicken is quite broad!), and that at the time it hatched, it was a chicken, then the egg came first. As above, there are reasonable ways for a non-chicken to lay an egg which hatches a chicken. I don't see any good ways around "egg came first" other than a definition of chicken that allows a non-chicken to become a chicken after it hatches. You could argue that the first chicken became one the first time someone called it that. Okay, but that seems pretty slippery, because if, today, a chicken is born in the woods and no human is aware of it, it's actually not a chicken, merely a bird that might one day become a chicken.