The chicken or the egg
I was just thinking, the other day, about the old question of which came first, and I decided that the egg undoubtedly came first; even dinosaurs laid eggs, but chickens I think are relatively recent.
Then I decided that, to be at all relevant, the question should really be, "Which came first: the Chicken or the Chicken–Egg?" Now the discussion is concerned with what makes it a Chicken–Egg; is it an egg a chicken lays, or is it an egg from which a chicken hatches?
Both of these, to my mind, are equally valid but if I had to choose, I'd say it was an egg the chicken laid because "Chickens lay Chicken–Eggs" seems more concrete to me than "Chickens hatch from Chicken–Eggs".
Things start to get complicated when you consider more than one generation of chicken; Chickens lay Chicken–Eggs from which Chickens hatch, thus implying that the laying and the hatching are linked which, arguably, they are. Following this backwards you get a chicken that hatched from an egg that was laid by a chicken that hatched from and egg that was… and so on. This suggests that chickens and eggs have always existed, which is nonsense.
The problem is that the chicken and the egg did not suddenly appear; they evolved over a substantial amount of time. Some animal, ultimately a bird though not necessarily having been one all the time, has evolved over millions of years to become the Chicken of today.
Therefore the Chicken and the Chicken–Egg have developed side by side; a Proto–Chicken laid a Proto–Chicken–Egg which hatched into a Proto–Chicken which laid a Proto–Chicken–Egg…
So, neither the Chicken nor the Chicken–Egg came first; they evolved side–by–side and arrived together.
On a similar note, don't forget that the world is flat and it's turtles all the way down…