Can Archaeology Dogs Smell Ancient Time?
sapiens.org
sapiens.org
Dogs can be trained to smell _cancer._ That is mind-bogglingly cool.
https://www.npr.org/sections/health-shots/2020/03/23/8202745...
Dogs being able to detect much more recent things does not surprise me at all
[0] https://www.pbs.org/video/welcome-to-fossil-country-mpoq6h/ (around the 18:50 mark)
I am really glad Apple put an EKG into their Apple Watch without being prompted by competition. Many people have been helped immensely by discovering underlying heart conditions through it.
You could build much smaller devices to detect particular molecules, but even a CO detector is about the size of your thumb. And it would take quite a lot of such devices to even begin to describe a real smell.
[1] https://en.wikipedia.org/wiki/Gas_chromatography%E2%80%93mas...
Also, a few months ago, an article was shared on HN explaining how dogs are able to detect heat with their nose. And this makes sense too: whenever I shower, my dog starts sniffing and scratching walls near the shower stall, where the pipe is.
I bet she could sense a rat hidden inside a wall or in the ground. Predator™.