While exploring the origin of the term “stool pigeon”, I happened on this interesting (if sad) article on far more than the the etymology of the saying. It is tied to the history of a massive, largely man-made mass extinction event.
“But while this term might evoke images of someone perched on a stool in a police interrogation room and being made to “sing” like a bird, the actual origins of this term are significantly more horrific, and tied to the greatest manmade extinction event in modern history.”
Check out this interesting article for all the details: