there are more stars and planets in the known universe than sand stones on our planet.
i dont deny the existance of alien life.
i just think that if any species is smart enough to travel lightyears to your planet, they surely have a smarter way of comunication than knicking down corn.

no aliens ever made contact with us. if they did, why leave? dont you think that NOT ONE alien woudl stay here to study us? really?
let me tell you about the fermi paradox. it says that WE are the only technologic race in the universe.
either because all other species are behind us OR because more advanced species were destroyed already...
think about that...