Gremlins.
I know. Just hasslin' ya... I got the right, I've actually met you. :)
Any deity worthy of a graven image can cobble up a working universe complete with fake fossils in under a week - hey, if you're not omnipotent, there's no real point in being a god. But to start with a big ball of elementary particles and end up with the duckbill platypus without constant twiddling requires a degree of subtlety and the ability to Think Things Through: exactly the qualities I'm looking for when I'm shopping for a Supreme Being.