Does the size of an animal’s nose predict how well it can smell? The answer is, perhaps surprisingly, no; in fact, the nose itself doesn’t do any of the actual odor detection. The nose pulls air past what’s called the olfactory bulb, an extension of the brain with chemical receptors, and it’s the binding of compounds to these receptors that allows one to smell things. The more compounds an animal can tell apart, the better it can smell. Here, scientists trained elephants to indicate whether two things smell different to them; in the process, they discover that elephants are better at smelling than… honeybees! Who knew?
Olfactory discrimination ability of Asian elephants (Elephas maximus) for structurally related odorants.
“Using a food-rewarded two-choice instrumental conditioning paradigm, we assessed the ability of Asian elephants, Elephas maximus, to discriminate between 2 sets of structurally related odorants. Read More
I have heard many heated arguments about the best way to store coffee (whole beans in the freezer, duh!), but nobody seems to care how long-term storage affects body odor samples. Does refreezing ruin them like it does ice cream? If I freeze my boyfriend’s sweaty shirt for six months, will I find it less “pleasant” or “attractive”? Well, I’m happy to say this study finally answers these questions, and then some.
Methods of human body odor sampling: the effect of freezing.
“Body odor sampling is an essential tool in human chemical ecology research. However, methodologies of individual studies vary widely in terms of sampling material, length of sampling, and sample processing. Although these differences might have a critical impact on results obtained, almost no studies test validity of current methods. Here, we focused on the effect of freezing samples between collection and use in experiments involving body odor perception. Read More
“Olfactory function influences social behavior. For instance, olfaction seems to play a key role in mate choice and helps detecting emotions in other people. In a previous study, we showed that people who were born without a sense of smell exhibit enhanced social insecurity. Based on the comments to this article we decided to have a closer look to whether the absence of the sense of smell affects men and women differently. Read More
“Chemosensory active volatile organic compounds occur in the breathing air at many workplaces and it has been assumed that they are potent to impair workers’ cognitive performance; however, the nature of this relationship is not understood. In the current study we investigated whether the combination of strong chemosensory potency and unpleasant odor valence is a sufficient predictor for the appearance of neurobehavioral impairment. Read More
“In recent years, bed bug (Hemiptera: Cimicidae) problems have increased dramatically in many parts of the world, leading to a renewed interest in their chemical ecology. Most studies of bed bug semiochemicals have been based on the collection of volatiles over a period of time followed by chemical analysis. Here we present for the first time, a combination of proton transfer reaction mass spectrometry and video analysis for real-time measurement of semiochemicals emitted by isolated groups of bed bugs during specific behavioural activities. Read More
“By application of the aroma extract dilution analysis (AEDA) on an aroma distillate isolated from a freshly prepared, stewed beef/vegetable gravy, 52 odor-active compounds were detected in the flavor dilution (FD) factor range of 4-4096. On the basis of high FD factors in combination with the results of the identification experiments, 3-(methylthio)propanal (cooked potato), 3-mercapto-2-methylpentan-1-ol (gravy-like), (E,E)-2,4-decadienal (deep-fried, fatty), 3-hydroxy-4,5-dimethyl-2(5H)-furanone (lovage-like), vanillin (vanilla-like), (E,E)-2,4-nonadienal (deep-fried), and (E)-2-undecenal (metallic) are suggested as key contributors to the aroma of the gravy. To get an insight into the role of the vegetables as sources of gravy odorants, a beef gravy was prepared without vegetables. Read More
“Gas-chromatography analysis of 90 samples of vaginal secretions from 10 women revealed that at any given sample time the perceptible vaginal odor of each individual women was composed of numerous separate odorous effluents. Read More
“Previous studies showed that orange odor reduces the anticipatory anxiety and improves the mood of patients waiting for scheduled appointments in small dental practices. We replicated these previous studies in the setting of three large dental clinics. In addition, we investigated whether another pleasant fruity smell (apple odor) is similarly associated with reduced anxiety. Read More
“Police officers frequently use the presence or absence of an alcohol breath odor for decisions on proceeding further into sobriety testing. Epidemiological studies report many false negative errors. The current study employed 20 experienced officers as observers to detect an alcohol odor from 14 subjects who were at blood alcohol concentrations (BACs) ranging from zero to 0.130 g/dl. Over a 4 h period, each officer had 24 opportunities to place his nose at the terminal end of a 6 in. tube through which subjects blew. Read More
“Our natural body odor goes through several stages of age-dependent changes in chemical composition as we grow older. Similar changes have been reported for several animal species and are thought to facilitate age discrimination of an individual based on body odors, alone. We sought to determine whether humans are able to discriminate between body odor of humans of different ages. Body odors were sampled from three distinct age groups: Young (20–30 years old), Middle-age (45–55), and Old-age (75–95) individuals. Perceptual ratings and age discrimination performance were assessed in 41 young participants. Read More