Noses Vary Inside and Out
What historical art of painted noses tell us about olfaction.
Posted Aug 10, 2013
When it comes to painting human noses, artists have always understood their obvious common characteristics; but more importantly, they have comprehended how dramatically noses vary from person to person. Throughout history, the portrayals of this anatomically proportioned protruding facial feature have been crucial in representing information and truth about their subjects. From the form’s physical contours and colorings, to the light and shadows of paint, visual depictions of the most forward facet of the face have offered revealing information about the diversity of humankind. Some noses represent iconic family traits and lineages, like the prevalent ones of the house of Medici, emphasizing bloodline and inheritance. Evidence of ethnicity, race, or region of origin, is often revealed by nose shape and size. Buttressing this approach to nose identity is considerable evidence that indicates that the nose’s form and internal structure evolved in relationship to climate. A man’s nose is generally larger than a woman’s—due to an adolescent surge of testosterone—and often, a subject’s sex can be identified by nose alone. Flared nostrils urgently convey an individual’s momentary psychology and his or her emotions of anger, arousal, or excitement; Portraits of red noses often express illness and alcohol abuse; An exaggeration of the nose has been indispensable, effective, and even abused, in portrayals of caricature.
Now, we must take note that aesthetic portrayals of the nose in all its varieties teach us about it as an organ of smell as well. It seems that our smell sensitivities and perceptions are as personalized as our nose’s visual appearance, as the chemical sense is shaped by the differences of our genetic blueprints. Expanding on our understanding of the genetic basis of olfactory receptors, recent findings reported in the journal Current Biology, by researchers of Plant and Food Research of New Zealand, headed by Sara Jaeger, Jeremy McRae and Richard Newcomb, have found that our ability to perceive certain odors and taste certain compounds, is mediated by our DNA dictating variations within olfactory receptors.
Jaeger, McRae and Newcomb began their research by testing ten scents used in processed foods, beverages, and other products on 187 people. Each person smelled all ten compounds and the odor concentration level at which it was perceived was documented. Each subject’s DNA was then sequenced and segments were identified that were likely linked to smell variations. Four compounds were found to have genes associations with them: malt (isobutyraldehyde), apple (β-damascenone), blue cheese (2-heptanone) and the floral smell (β-ionone). Interestingly, traits that govern olfactory sensitivity, controlling odor experience or recognition, were found to be the same across cultures. Considering this information, we can say that we all not only have unique noses, we perceive the world through a personalized smellscape that affects the way we smell, taste, remember, behave, and express emotion.
Reflecting on the nature of odor processing that goes on high up in the nasal passages, some scientists have hypothesized that the reduction of physiological properties necessary for smell function, in what may be a growing in percentage of individuals, might be explained as an evolutionary adaptive change that amounts to a trade-off of human olfactory capacity for vision advantages, as vision replaces smell as the primary sense crucial to survival. The artist’s keen skills of observation and deduction about the nose may have come at the cost of smelling the rose or violet he or she paints.
Copyright © 2013 by Gayil Nalls