I read a science fiction story once about two aliens discussing life on earth.
“What about number 3 of Sol?”
“Oh, well the intelligent life search turned up positive but they are not ready.”
“Not ready? They have RF emissions, they must be ready!”
“Well, we analyzed the RF emissions. They are just meat noises. The beings there are meat. They send pictures of the meat. They blow gas through holes in the meat to communicate, and they use machines to send RF coded emissions of the meat sounds. Quite clever in a way.”
“Are you sure? Remember Telex-4, that looked like meat, but actually had a carbon core?”
“No, we picked up a few, and probed them. They are all meat.”
“Well, I agree with your assessment. Some forms of life are just too disgusting for our federation to accept.”