Human Olfactory sense is Underrated

Researchers at the University of California at Berkeley conceived an experiment of their own which, though it looked funny at times, came up with some serious evidence. It appears people can follow a scent surprisingly well, having nothing else to rely on but their noses. Those who participated in the experiment were blindfolded and asked to wear sound-muffling headphones as well as thick gloves, kneepads and elbow pads. A line of string was dipped in chocolate scent and then embedded in the grass, and the participants crawled away on all fours, trying to follow the track (this being the funny part of the research); they couldn’t see the string or feel it.

The serious part came when researchers found that their subjects were actually close on the trail – slowly but surely the people followed the scent and even took turns as the trail did.

The purpose of the experiment was to ascertain whether having two nostrils spaced slightly apart helps track a scent, just as having two ears enables the brain to locate the source of a sound.
When each nostril was blocked, the participants' scent-tracking accuracy dropped dramatically.

The study indicates that there is a strong purpose for humans having precisely two nostrils: the human brain compares data it gets from each nostril to get clues about where a smell is coming from. The Berkeley study demystifies the theory that says human nostrils are too close together to get distinct signals.

By revealing how noses locate smells, scientists hope to lay the groundwork for electronic noses that could detect hazards like land mines. The work was funded in part by the Army Research Office.
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