From Wikipedia:
"Miner's canary
Canaries were once regularly used in coal mining as an early warning system.[3] Toxic gases such as carbon monoxide, methane or carbon dioxide in the mine would kill the bird before affecting the miners. Because canaries tend to sing much of the time, they would stop singing prior to succumbing to the gas therefore alerting miners to the danger. The use of so called miner's canaries in British mines was phased out in 1987.[4]
Hence, the phrase "canary in a coal mine" is frequently used to refer to a person or thing which serves as an early warning of a coming crisis. By analogy, the term climate canary is used to refer to a species that is affected by an environmental danger prior to other species, thus serving as an early warning system for the other species with regard to the danger."
In the game Taboo, one person has to get the other players to guess the word on a card, without saying a list of related words. In last night's game, someone had the word "canary", which led to a discussion of how the bird used to be sent into a mine to detect deadly gas, before miners entered. Upon hearing this, a piece of my heart died. "WHY
would they use the canary???" I cried. "It's so beautiful and yellow and it sings so pretty! Why couldn't they use a mockingbird or something!"This led us to the conclusion that a book would probably be written about the tragic plight of these mockingbirds.
Then we realized it had, in fact, already been written. So much for my debut novel To Kill a Mockingbird: The Story of How the Canary Escaped from the Mines, & Was Replaced by the Mockingbird.
