Corn is bleieved to be form space, and is only related closely to some grass. (now worlds largest crop).

Mushrooms are from space. Mabe alenes are sending us drug strains, this all happened before we were what we are today ehh? Cannabis grows strong and quick, so does mushrooms. Mabe we are supposed to be a harvesting planet. Grow dugs on here. Or get some primative civilizations to cultivate, then oneday drop bye and steal all our drugs. Were mabe the amerstardam of the galexy. I hope not though, otherwise our galexy is pretty bland. :P.

OR mabe they just figured they would help us out.