If you have been to the airport or any public place since 9/11, we see dogs standing next to security people at the ready because of their ability to smell explosives. Police dogs have also been used for missing persons or finding the remains of a deceased person. Did you know that dogs can smell diseases and sense seizures before they happen? Dogs possess about fifty times more olfactory receptors in their noses compared to humans and the part of the dog’s brain that is devoted to analyzing smells is about 40 times greater than humans. Dogs also have a vomeronasal organ which enables them to detect pheromones, which are chemicals that transfer information to another member of either the same or another species.
There are humans that are also capable of smelling disease, they are called super smellers. Joy Milne a “super smeller” who is capable of detecting scents too subtle for most people to perceive and is also a retired nurse living in Perth, Scotland. Joy first noticed a “sort of woody, musky odor” from her husband about 12 years before his diagnosis of Parkinson’s disease. Tilo Kunath, an Edinburgh University neurobiologist became aware of Milne’s observations of smell during a lecture he gave in 2012. Milne’s husband Les had since passed away, but Kunath tested Milne by having her smell 12 shirts worn by a mixture of healthy volunteers and patients diagnosed with Parkinson’s. Milne correctly picked out the six shirts worn by those suffering from Parkinson’s disease. She also picked another shirt that was initially thought to be a normal volunteer, but eight months later it was later learned that the shirt the person belonged to was diagnosed with Parkinson’s!