I have several things to add:
First, the concept that "aliens" planted us here is just as likely a possibility as say, we were grown anthropods and all those realitive shenanigans. Point being, it is a theory, not truth, and does not counter any thoughts or belifes in some all powerfull being.
Second, who says that we couldnt do something along this theory? Create a bacteria that can live in conditions particular to a certain enviroment on a seperate planet, send it to said planet, and watch it evolve. This something that could truly prove an evolution theory, although it still does not discredit God.
Thirdly, I belive some one mentioned Cuneiform. You have seen 'The Fourth Kind' way too many times. Yes, this primitive writing has mathmatical formulas in it, but it cannot be said that they were ahead of us in tangents and so on because the were using 60 numbers instead of 10. Not to mention you can also declare that there is mathmatical value within my own ass. So much for Babylon. I suppose you would also suggest that pyramids are landing platforms, (yes i watch movies too.)
Lastly, if this subject interests you, try fathoming the concept that maybe these "intergalactic visitors" are our god's. There is a book by a, I belive Swiss, archeologist, whose name escapes me at the moment, that wrote a very interesting novel that centers around this very subject. The book is called 'Chariots of the Gods?". It bases itself around acient civilazations that were possibly influenced by extraterrastrials. Such empires include; Egypt, Mesopatamia, and the Central and South American Civ's (Aztecs, Inca's, ect......). Its a very good read and should shed some light for those looking to learn more about this subject so that you have a better example of some of the history.