“What’s indisputable is that, before humans milked cows, herded goats or raised hogs; before they invented agriculture, or written language, even before they had permanent homes, humans had dogs in their lives or dogs had humans in theirs lives,” I wrote back then.
Outside being a best friend and companion, dogs have unique traits that we have used through the ages to help and protect us in many ways. Maybe none greater than their sense of smell. “With up to 300 million scent receptors, dogs are among the best smell detectors in the animal world,” writes a team of forensic and biochemistry researchers in a post on TheConversation.com. “The human nose, by comparison, contains only around 6 million scent receptors. Dog brains also devote 40% more brain space than humans to analyzing odors.”
Beyond their natural instincts, we have been able to train dogs to use their sense of smell to sniff out all manner of things from illegal drugs to agricultural pests, to missing people.
“Dogs accomplish this by successfully recognizing the odors of substances called volatile organic compounds that are specifically associated with these targets. Not only can trained dogs detect these volatile organic compounds, but oftentimes they can do it with greater sensitivity than analytical instruments,” say the researchers. This unique sense of smell has also been successfully used to recognize “unique ‘biomarkers’ in the exhaled breath of patients with certain diseases or chronic medical conditions, including cancer and diabetes, as well as for pre-seizure detection in epileptic individuals.”