We’ve all heard the canary-in-the-coal-mine history.
Just over 100 years ago, in 1911, John Scott Haldane, a Scottish physician and research professor of physiology at Oxford University became known to some as “the father of oxygen therapy,” in part because he used science to test and recommend using birds – specifically canaries – to detect carbon monoxide and protect coal miners.
Canaries, and other birds, are good early detectors of carbon monoxide because they need immense quantities of oxygen to enable them to fly. Their anatomy allows them to get oxygen when they inhale and still more when they exhale, by holding air in extra sacs. That meant that in mines they got a double dose of air, along with any poisons the air might contain. If they became ill or died, the miners had an early warning to evacuate.
It wasn’t until 1986, when more scientists developed the “electronic nose,” a detector with a digital reading, that the canaries were freed from their dangerous duty, according to Smithsonian Magazine.
But birds – some 389 North American species of them to be exact – are still warning us of danger from carbon monoxide and its cousin carbon dioxide – two important drivers of climate change. And scientists again are researching the birds’ warnings and telling us how to read the signs.