Studying Disgusting Things in Science and the Science Behind What We Find Disgusting

Expression of Disgust

Some areas of research are glamorous, such as the stars, the genome, or dinosaurs. Some other areas of research are vital to our well-being, such as vaccines, heart disease, and cancer. Other areas of research are fun, such as puzzles and game theory. And the best thing about research in these areas is that you can talk about it during lunch, dinner, and cocktail parties!
 
However, some areas of research delve into subjects that most people would consider downright disgusting. But what are scientists to do if their pursuit of the scientific truth leads them to spend long hours in the office, the field, or the lab designing and carrying out experiments or analyses dealing with slimy icky things, body parts, tissue samples, or bodily fluids? In this post we are going to see why people consider some things disgusting, but first we are going to go over some examples of research into disgusting things that scientists have published.
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Coincident Tick Infestations in the Nostrils of Wild Chimpanzees and a Human in Uganda by Hamer and coworkers, published in The American Journal of Tropical Medicine and Hygiene in 2013.
Here a scientist studying ticks in the nostrils of chimpanzees found that one of these arachnids had latched on to his own nose. He took it out, sequenced its DNA, and found out it may be a new species!
 
Buttock Augmentation: A Novel Alternative to a Lengthy Procedure by George Solomon, published in The American Journal of Cosmetic Surgery in 2016.
Who would not be interested in coming up with a better procedure to increase buttock size?
 
The effect of acute increase in urge to void on cognitive function in healthy adults by Lewis and coworkers, published in the journal Neurourology and Urodynamics in 2011.
In this research, scientists had people perform cognitive tasks while drinking fluid. The researchers found that the more you want to pee, the less well you perform in a cognitive task. Good to know!
 
Volatile components in defensive spray of the hooded skunk, Mephitis macroura by Wood and coworkers, published in the Journal of Chemical Ecology in 2002.
Here the researchers investigated all the chemical compounds present in the anal sack of a variety of skunk. This research stinks!
 
Experimental replication shows knives manufactured from frozen human feces do not work by Eran and coworkers, published in the Journal of Archaeological Science: Reports in 2019.
An old story in archeological circles stated that a man made a knife from his frozen feces to butcher an animal. The researcher here found out these knives do not work. So now you know what not to do when trying to butcher an animal.
 
The fate of the embedded virgin sand flea Tunga penetrans: Hypothesis, self-experimentation and photographic sequence by Thielecke and Feldmeier, published in the journal Travel Medicine and Infectious Disease in 2013.
In this article, a researcher found that a sand flea had burrowed under her skin. She allowed it to remain there and made observations that permitted her to gain insight into how sand fleas reproduce. Now, that’s dedication!
 
The effect of Having Christmas Dinner with In-Laws on Gut Microbiota composition by de Clercq and coworkers, published in the Human Microbiome Journal in 2019.
Yes, you read that right. These researchers investigated how having dinner with your in laws changes the bacterial composition of your intestinal contents.
 
Personal space invasions in the lavatory: suggestive evidence for arousal by Middlemist and coworkers, published in the Journal of Personality and Social Psychology in 1976.
Here researchers found that men who have other men peeing next to them take longer to begin peeing. I would just sing that song, “Don’t stand so close to me.”
 
Biomechanics of male erectile function by Daniel Udelson, published in the Journal of the Royal Society, Interface in 2007.
The author of this article studied the male organ and came up with complex mathematical equations that describe its buckling as well as blood flow through it. This guy is an expert.
 
Pressures produced when penguins pooh—calculations on avian defaecation by Meyer-Rochow and Gal published in the journal Polar Biology in 2003.
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As it turns out, some researchers not only study disgusting things, but they also study why you find the things they study disgusting!
 
The observation was made a long time ago that those things that people find disgusting are related in various ways to infectious diseases. So, scientists have developed the hypothesis that the feeling of disgust in animals such as humans evolved to affect behavior in such a way as to reduce the risk of infection. This is the so called “parasite avoidance theory”.
 
A group of researchers tested the theory by performing an experiment where they presented several disgusting scenarios in writing to a total of more than 2,600 participants in a study. These scenarios ranged from watching people pick their nose, spotting an unflushed toilet, or seeing pus come out of a genital sore, to accidentally using someone else’s deodorant, eating onion flavored ice cream, or watching a fly crawl across the face of a sleeping friend. The participants were asked to rate each scenario in a scale from 0 (no disgust) to 100 (extreme disgust). Using statistics, the scientists found that the responses of the participants could be categorized into six factors: avoidance of skin lesions, spoiled foods, animal vectors, promiscuous sexual practices, and individuals with poor hygiene or atypical appearance. This suggests that human beings have an instinctive “pathogen detection system” that leads them to avoid people, practices, and objects associated with infectious disease.
 
But research into disgust is not merely an academic endeavor. Disgust plays an important role in anxiety and phobias, and disgust is an emotion that can often affect our judgement in subtle ways. For instance, in another study researchers asked people to make moral judgments in environments where they were exposed to disgusting stimuli such as a bad smell. They found that people in the disgusting environments tended to make harsher moral judgments. This awareness of the effects of disgust in human psychology has been applied to promote the avoidance of behaviors by people that can lead to spread of disease. Unfortunately, it can also be misapplied to fan prejudice and stigmatize individuals or entire groups of people. For example, studies have revealed that people that are more prone to being disgusted have a greater intuitive disapproval of gay people, and in the past (it is more subtle nowadays) much anti-gay propaganda contained associations with disgusting images and statements.
 
 
Disgust expression photo by Eric Molina from flickr is used here under an Attribution 2.0 Generic (CC BY 2.0) license.