Those of us without 20/20 vision are probably familiar with the tricks of trying to see better. You know, when something in the distance is fuzzy so you squint your eyes a bit in order to make it a little clearer? When people do that, they’re limiting the amount of bent light rays that can enter the eye. Straight light rays don’t need correcting in your eye’s lens, thus they are unaffected by imperfections in its focusing abilities.
That’s a pretty neat trick, being able to modify something physical in order to improve our sense of sight. Just imagine if every sense worked like that. What if we could change the shape of our ears in order to hear someone better in a noisy crowd? What if we could change the shape of our noses in order to pick up on faint scents?
Well then we’d be more like rats.
According to new research from the University of Chicago’s Leslie Kay, that is exactly what rats are able to do with their sense of smell. By hooking up electrodes to the rats’ diaphragm muscles and training the rats to look for a specific scent, scientists were able to detect a change in their approach depending on the scent they were sniffing out.
By altering their diaphragm muscles, the rats affected the amount of airflow coming in through their nostrils. If they were trying to detect odorants that readily absorb into mucus, they took sharp, fast breathes because the front part of their nasal cavity is more sensitive to highly absorbent odorants. Conversely, rats attempting to detect odorants that are not highly absorbent took longer, more sustained breaths in order to get the scent towards the back of the nasal cavity, where those types of odorants are more likely to be detected.
The researchers think it is likely that other animals are capable of the same feat of focusing their sense of smell depending on what it is they’re looking for. It turns out that smelling isn’t a cut and dry matter of the physical properties of odor.
It also matters how you sniff.