I've always thought it was the egg, out of a certain romantic notion that it's the primordial egg from which everything comes from. Anyway, finally somebody has made it their business to ponder the age-old question of which came first, the chicken or the egg? That's one less mystery now in our world, although if you come to think of it, maybe it's better we didn't know at all. Some things are better left head-scratchingly unanswerable. Video from AsapSCIENCE.