Irreducible complexity is an argument used to refute Darwinian Evolution. Irreducible complexity means that “new life cannot come into existence by the Darwinian method of slight successive changes over a long period of time … As with a car engine, all the right parts must be in place in the right size at the same time for there to be any function at all. You can build an engine part by part (and that takes intelligence), but you can’t drive to work with only a partial engine under the hood. Nor could you drive to work if one essential part of your engine were modified but others were not. In the same way, living systems quickly would become nonfunctional if they were modified piece by piece.” (I Don’t Have Enough Faith To Be an Atheist, Pg.146, 145).
The Chicken came first.