I’m always impressed by the olfactory feats my canine companions Jill and Samson can accomplish. From searching a field for a groundhog to chase, to lasering in on the treat bag as I pull it from the kitchen shelf, I’m envious sometimes of the whole other world of scents they seem to inhabit!
Well, science may be showing that envy is not required: humans may actually have senses of smell comparable to that of dogs, and other big smellers like rodents. While we bipeds may have been socialized to not pay keen attention to scent input, we actually have competitive numbers of odour receptor genes, as well as a large olfactory bulb compared to the size of the rest of our brains. John McGann, a neuroscientist out of Rutgers and author of a recent paper in Science attempting to dispel the myth of humans as poor smellers, believes these physical realities translate into a better smelling skill set for us. McGann goes back to other studies and attempts to set the record straight. From the Guardian:
“Humans have approximately 1,000 odour receptor genes, for instance, compared to 1,100 in mice, which some had taken as confirmation of mouse superiority. However, other work suggests there is not a tight relationship between the number of olfactory genes and smelling ability. One study found that cows have 2,000 such genes – far more than dogs.
Even the constant sniffing of some animals may also be misleading, McGann said. When a rat is exposed to a new smell, for instance, it performs ‘fast investigative sniffing’ but rats have the same reaction to hearing an unfamiliar new sound or seeing something unexpected. ‘Sniffing, to some extent, means “I’m curious”,’ he said.” [Or, as we saw last week, “I’m anxious.”]
McGann does concede a few points to the dogs though – that the reason they can detect the smell of explosives and we can’t could be due to the higher concentration of olfactory receptors in their noses. And critics of McGann’s work say that dogs have always been better at the kind of scent work (like tracking, sussing out drugs, or detecting kinds of cancers) that humans could not aspire to, even with the attention of a sommelier. But I think we could definitely fall somewhere in that huge middle ground between bloodhound and Pet Rock! If the nose knows, it’s only a matter of letting it do its thing, and the science will follow.