People usually assume that this is just one of those rethorical questions, but does science have an answer to that ancient riddle?
http://www.straightdope.com/classics/a2_218.html
It’s been done already…
I always wanted to know which came first: the chicken-salad sandwich or the egg-salad sandwich? 
Zev Steinhardt
Thank you!:}
A chicken and an egg were laying in bed. The egg looks over at the chicken, smiles, takes a drag on a cigarette, and says: “Well, I guess that answers that question”.
Actually, looking at Cecil’s answer, it seems like the question itself is too broad. The question becomes more answerable if it’s asked as "What came first, the chicken or the chicken egg?
An egg was laid by a chicken precursor, which resulted in the first chicken. But was that egg truly a chicken egg, not being laid by a chicken? Or, the way I’m thinking of it, was the first chicken a result of another creature’s egg, and so, the first true chicken egg was laid by the first chicken? Is it the producer of the egg or the result of the egg which specifies what kind of egg it is? Or is it both?
It seems to me that the chicken came first.
[sub]“Too much time on my hands”, says the little inner voices…[/sub]
You sort of answered your own question: If the pre-chicken- creature laid an egg that contained a chicken, in hindsight we would know it was a chicken egg. The chicken egg came before the chicken.
The philosophical chicken came before the philosophical egg because the first simple creature (the philosophical chicken) pre-dates any egg or hatching mechanism.
… and how about the egg that the Silly Putty comes in? Did that come before or after the Silly Putty?
If we look at the question genetically, the mutation that led to the genetic entity we know as a chicken happened in the sex cells of some earlier non-chicken. So, the egg that creature laid contained pure chicken DNA.
So, the egg that was genetically a chicken egg preceded the creature that hatched from such eggs.
If you follow the line of ancestry far enough back, you’ll find the eggs to be laid not by a chicken exactly, but by some form of pre-chicken reptile, in turn descended from the dinosaurs (which unquestionably did lay eggs). Unknown to modern science is the answer to the question “Did dinosaurs really taste like chicken?”
Anyway, “the egg” did come before “the chicken”, by millions of years.
Old joke: “A chicken is just an egg’s way of making another egg.”
The egg wins out, as is obvious after giving it more thought. Thanks folks. Now I can move forward with my life, secure that my level of ignorance is ever so slightly less then it was when I awoke this morning.
Of course, given the slow pace of evolution, the non-chicken that laid the chicken egg would be 99.999whatever% chicken itself. The human classification of species does have some subjectiveness to it so that we’d probably call the parent a chicken too. Bottom line, the transition from non-chicken to chicken is a gray area. Remember a whole population must follow suit, not just one individual.
The egg is a presumptuous chicken & the real comes before the presumptuous, thus the chicken before the egg, duh.
Does this mean everyone has to don a chicken suit just like that guy in San Diego? And, what if I’m clautrophobic and didn’t want to put on the suit, would that mean I’m too chicken to be a chicken?
Just checkin’.
This thread made me think what would happen if you changed the situation to be a baby/parent relationship? Which came first, the parent or the baby? The logical answer is that the parent came first, but wasn’t that parent once a baby? Therefore, the chicken was once an egg?
Of course, the real question is “which came first - the mycelle or the ribozyme?”