I’d like to start by saying, before actually having read the article at the link below, I had come to exactly the same conclusion, so I’m not disputing this answer.
http://www.straightdope.com/columns/read/479/which-came-first-the-chicken-or-the-egg
However…
If you really take the intent of the question to mind, I’m not so sure the second answer is as “retarded” as is purported.
The question “What came first, the chicken or the egg?” is intended to be a paradox, and one can deduce that the question is in fact worded improperly for our contemporary times and instead should be worded “What came first, the chicken or the chicken egg?”.
If worded like this, the paradox still exists. The answer then depends on whether the type of egg is determined by what animal laid the egg, or what animal hatches out of the egg.
Let’s say that the chicken’s direct ancestor (for the sake of argument, we’ll say it was a dodo) reproduces by way of laying an egg, but through the miracle of evolution, a mutation causes the offspring occupant of that egg to be a chicken instead of a dodo. Was that egg that hatched a dodo egg, because it was laid by a dodo, or was it a chicken egg because it’s occupant was a chicken?
This question is at the heart of the dilemma. If a dodo lays a dodo egg that happens to hatch a mutant which is a new species called chicken, well then the chicken came first, and the chicken egg doesn’t come along until that chicken lays an egg. Conversely, if a dodo lays a chicken egg, well then clearly the chicken egg comes before the chicken (unless you get into the business of when the egg shell actually forms around the fetal chicken, and at what point the fetus is considered a chicken).
I’m sure this has been a waste of time to anyone who bothered to read it, but I just needed to add my piece (which in all likelihood isn’t even an original argument, although it’s at least original to me), especially because the answer given by Cecil (while correct) was based on the literal interpretation of the question and not the intent.