The title of this post is from Terry Bisson’s story, They’re Made Out Of Meat, which he has made available online with this introduction:
From OMNI, April 1991. This story, which was a 1991 Nebula nominee, has been appearing around the internet lately without my name attached. Several people were kind enough to alert me, but the truth is I’m more flattered than offended.
Update: Someone made a short-film from the story, someone with money: I recognize the actors.