Well, you have seen them, so what do you say now?
Of course, your arrowhead is just a version of Paley's "watch in the wilderness". His argument, and yours, is incoherent, however. The watch is placed in contradistinction to nature, and by analogy we are supposed to place nature in contradistinction to itself. It's a specious argument.
My experiment, I get to ask the questions. What does acorns and watches have to do with it?