» HOW THE NOSE KNOWS: Vibrations?

by Brian Awehali

Fifth-Century Greek philosopher Democritus, the putative founder of modern science and atomic theory, who laughed constantly and lived more than one hundred years, once had occasion to ponder our sense of smell. It was, he theorized, the result of our nose reading the shape of airborne particles. Democritus called these particles “atoms,” and he thought sweet atoms were “round and of a good size,” while sour ones were “bulky, jagged, and many angled.”

This “shapist” theory of smell, or olfaction, continues to this day. It boils down to the essential concept of tiny pieces of things being “read” by receptors in our nose. Democritus called these pieces “atoms,” but he had no sense of atomic theory in the modern sense, which asserts that these pieces are, in fact, molecules. But that’s just a theory, and the truth is that no one really knows how our sense of smell works. The shapist theory has many inconsistencies and demonstrated limitations. Molecules with the same shape produce different smells; inversely, two molecules with completely different shapes can produce the same smell (sandalwood).

On August 6, 1945, at 8:15am, miles away from the site of the Hiroshima bombing, people reported an impossibly bright light and the smell of burning rubber. This posed a problem for the shape theory of smell: If smell was the result of particulate matter – molecules – landing on receptors in the nose, how then to explain the instantaneous travel of molecules from the blast site to noses miles away?

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by Brian Awehali

The first time you kiss somebody, you may well be caught up in romance and various libidinal tides, but your brain and olfactory system are hard at work, gathering information to decide whether to take it to the “next level.” At least that’s how the assembled panelists and journalists at a recent American Association for the Advancement of Science meeting in Chicago saw the process.

“You’re not just kissing,” said one scientist suggestively, “you are likely absorbing information about your partner’s immune system, looking for a good match should you two procreate.”

Other scientists in attendance copiously supported their colleague’s assertion by noting findings in related studies. “A similar tendency has also been found,” asserted one postdoctoral researcher in the Berkeley Olfactory Research Program, “in some rather interesting tests where women sniffing male armpit sweat chose those indicating immune systems complementary–not similar–to their own.”

Certainly there exist women for whom the idea of a long session of male armpit huffing evokes an unseemly dark thrill. You might hope that one or more such women were among those who signed up for this study. But when pondering this pit-sweat-sniffing story, one must consider the long tour of ignominies visited upon countless women that led up to this particular moment in scientific history, and the moment in which each woman in the study was bade: Choose the best armpit.

(Alternately, the study may not have involved live male armpits at all, but rather the sniffing of previously collected male armpit sweat. Either way, it’s an odd study. It also provides me a rare opportunity to link to an only slightly related Old Spice commercial about armpits, men, manliness, and frenching):

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