Scientists are nothing if not endlessly curious, and sometimes that trait can lead them into unusual research directions. Maybe they find themselves exploring whether sex could be a natural alternative to nasal sprays for relieving nasal congestion, or maybe they’ll end up taking the vitals of a rhinoceros while the animal is sedated and suspended from its feet for helicopter transport. Perhaps they might find surprising insights into how cats communicate or into the bacteriomes of discarded wads of chewing gum from different parts of the world. These and other unusual research topics were honored tonight in a virtual ceremony to announce the 2021 recipients of the annual Ig Nobel Prizes. You can watch the livestream of the awards ceremony above.
Established in 1991, the Ig Nobels are a good-natured parody of the Nobel Prizes that honors “achievements that first make people laugh, and then make them think.” The unapologetically campy award ceremony usually features miniature operas, scientific demos, and the 24/7 lectures whereby experts must explain their work twice: once in 24 seconds, and the second in just seven words. Acceptance speeches are limited to 60 seconds. And as the motto implies, the research being honored might seem ridiculous at first glance, but that doesn’t mean it is devoid of scientific merit.
Viewers can tune in for the usual 24/7 lectures, as well as the premiere of a miniopera, A Bridge Between People, in which children try to mediate between argumentative adults by building actual tiny suspension bridges between them—in keeping with the evening’s theme of engineering. Traditionally, the winners also give public talks in Boston the day after the awards ceremony, although the pandemic put a kibosh on that for the second year in a row. Instead, the winners’ talks will once again be given as webcasts a few weeks from now.
Here are the winners of the 2021 Ig Nobel Prizes.
Citation: Susanne Schötz, “for analyzing variations in purring, chirping, chattering, trilling, tweedling, murmuring, meowing, moaning, squeaking, hissing, yowling, howling, growling, and other modes of cat–human communication.”
Schötz, a researcher at Lund University in Sweden, was struck by a talk several years ago comparing the purring of a big cheetah with a domestic cat, which found that both animals purred at around 30 Hertz, despite the significant difference in size. Intrigued, she went home and recorded the purrs of her own cat Vincent as well as those of three young kitty siblings from the same litter—Donna, Rocky, and Turbo—who found their way into her care. Thus began a yearslong project to better comprehend the different vocalizations of domestic cats, spawning five separate papers (in 2011, 2012, 2013, 2014, and a review paper in 2016). Donna, Rocky, and Turbo were the subjects in all of the studies.
Cats purr for many different reasons: when they are angry, stressed, in pain, and yes, when they are contented and happy. But the phenomenon has not been well-studied, particularly when it comes to acoustic analysis. They also chirp, chatter, trill, moan, yowl, meow, growl, and hiss, among other common vocalizations. Schötz has found that a combined murmur and meow is the most common kitty utterance, while watching birds through a window will elicit chatters, chirps, tweets, and tweedles (prolonged chirps or tweets). Meows for food will have a rising contour to the pitch, while meows associated with a trip to the vet have falling pitch contours.
Based on all that previous work, Schötz and her collaborators received a grant to study “Melody in Human-Cat Communication,” playfully dubbed “Meowsic.” The ultimate goal is to collect even more data in support of their key hypotheses: that cats “semi-consciously” alter intonation, intensity, length, and quality of their vocalizations to fit different contexts; that most cats share similar types of this so-called “prosodic variation”; and that these variations can be correctly interpreted by experienced human listeners. Most cat owners would probably agree.
Citation: Leila Satari, Alba Guillén, Àngela Vidal-Verdú, and Manuel Porcar, “for using genetic analysis to identify the different species of bacteria that reside in wads of discarded chewing gum stuck on pavements in various countries.”
People have been chewing some form of gum for millennia, from wood tar during the Mesolithic and Neolithic eras, all the way up to the many varieties of commercial chewing gum sold around the world today. Once the gum has released all its flavor, people have a bad habit of depositing the spent wad on public surfaces, especially walls and pavements—or priceless works of art. Sometimes it even becomes a tourist attraction, like Seattle’s notorious “gum wall” located in an alley behind Pike Place Market. (The wall was steam cleaned to remove 20 years of accumulated gum in 2015.)
But discarded chewing gum also offers potential positive benefits. In addition to DNA, used gum can contain oral bacteria as well as certain opportunistic pathogens like Streptococcus spp. and Corynebacterium spp. Leila Satari and her co-authors at the University of Valencia in Spain set out to characterize the bacteriome of discarded chewing gum from five different countries—including the streets around their Valencia laboratory—and monitor how it changed over time. Their experiments also involved chewing 13 gum samples (Orbit and Trident brands) and placing the wads in outdoor pavement for up to 12 weeks, monitoring how the bacterial content changed.
Satari et al. found a moderate degree of diversity in terms of the bacterial populations in the chewing gum samples. They also found that, over the course of a few weeks, the kinds of microbes typically found in recently chewed gum (the oral microbiome) gave way to microbes typically found in the surrounding environment. “Taken together, our results suggest that bacteria can play a role in the natural biodegradation of the chewing gum and may also be a source of strains with other biodegradable properties,” the authors concluded in their paper. And while there are concerns about wasted chewing gum carrying pathogenic microorganisms, the relative longevity of the oral bacteria could prove useful in the legal and forensic arenas, akin to DNA analysis.
Citation: Jörg Wicker, Nicolas Krauter, Bettina Derstroff, Christof Stönner, Efstratios Bourtsoukidis, Achim Edtbauer, Jochen Wulf, Thomas Klüpfel, Stefan Kramer, and Jonathan Williams, “for chemically analyzing the air inside movie theaters, to test whether the odors produced by an audience reliably indicate the levels of violence, sex, antisocial behavior, drug use, and bad language in the movie the audience is watching.”
Everyone knows that the process by which ratings boards determine film ratings is highly subjective, based on what they consider to be age-appropriate material for different audiences (violence, sexual content, profanity, drug use, and so forth). Wouldn’t it be nice if studios could monitor the breath of audiences during test screenings to get a more objective measure of how certain content is affecting them?
This team of German scientists certainly thought so and published an intriguing study back in 2015 that identified key chemical signals—in the form of exhaled volatile organic compounds (VOCs)—in response to specific scenes in a given film. When the audience’s collective pulse and breathing rate increases in unison, special sensors can detect corresponding rises in CO2 and hundreds of other VOCs, some of which were found to correspond to specific types of scenes. The effect proved strongest with suspense and comedy scenes.
Wicker et al. followed up with a second paper in 2018, attempting to demonstrate proof of content for using these VOC measurements as tools to make age-appropriate classifications for films. The data was collected from 135 screenings of 11 different films, measuring the exhalations of some 13,000 viewers who attended screenings at a multiplex CineStar theater in Mainz, Germany. Unfortunately, “Most compounds were not able to predict all age classifications reliably,” the authors concluded. This might be due to a mismatch between subjective “perceived sensibilities” and biological responses, they reasoned, or due to the small number of films included in the study. The one bright spot was isoprene, the only compound that reliably predicted three out of five German age classifications: FSK 0, 6, and 12.
Citation: Robin Radcliffe, Mark Jago, Peter Morkel, Estelle Morkel, Pierre du Preez, Piet Beytell, Birgit Kotting, Bakker Manuel, Jan Hendrik du Preez, Michele Miller, Julia Felippe, Stephen Parry, and Robin Gleed, “for determining by experiment whether it is safer to transport an airborne rhinoceros upside-down.”
The wild black rhinoceros (Diceros bicornis) faces a serious threat from poachers in southern Africa, along with agriculture development encroaching on its turf. This is leading to too much inbreeding. So African governments have taken to occasionally relocating the rhinos to different geographical regions to mix things up a bit. The problem is that transport by truck is difficult if not impossible, given the rugged terrain, so the Namibian Ministry of Environment and Tourism (MET) has resorted to transporting the rhinos aerially. This involves sedating the ungulates (from a safe distance) with a potent opioid and then suspending the drugged rhinos by their feet under the helicopter for as long as 30 minutes.
Robin Radcliffe (Cornell University) and his co-authors noted that nobody had studied the physiological effects of this practice on the rhinos. Concerns include whether there were adverse effects from the opioids used (complications can include hypoventilation, hypoxemia, hypercapnia, or hypertension) and from suspending the sedated beasts upside-down compared to being in a horizontal position when being transported by truck. (An animal’s posture under anesthesia can affect cardiovascular and pulmonary function.) Their study involved 12 sedated rhinos. Six were placed first in a horizontal (lateral recumbent) position before being suspended by their feet, while six others had the order of the two positions reversed. The researchers took several measurements of key vital signs while the animals were in both positions.
Radcliffe et al. had hypothesized that the animals’ upside-down posture would result in more adverse effects than the horizontal (lateral) position. But their results failed to bear that out. All 12 rhinos showed signs of severe hypoxemia (low blood oxygen) and hypercapnia (excessive CO2 in the blood). However, suspending rhinos from their feet for 10 minutes “did not impair pulmonary function more than did lateral recumbency,” they wrote.
Citation: Pavlo Blavatskyy, “for discovering that the obesity of a country’s politicians may be a good indicator of that country’s corruption.”
In the popular imagination, corruption and politics often go together like chocolate and peanut butter, only with far less desirable outcomes. According to Blavatskyy, a researcher with the Montpellier Business School in France, prior studies have shown that political corruption (like bribery and extortion) can lower a country’s economic growth, increase costs for road construction, deter foreign investment, and increase public debt, among other adverse effects. But measures used to determine how corrupt a given country’s political leaders might be tend to be highly subjective. In this paper, Blavatskyy proposes an alternative, more quantifiable methodology for assessing corruption: the body mass index (BMI) of political leaders.
Since medical records are generally not obtainable (if they are kept at all) for political leaders, Blavatskyy decided to test whether computer vision/machine learning could determine a person’s BMI using facial recognition. He selected 299 sample images of the faces of political leaders from 15 post-Soviet states, “because corruption is perceived to be a significant problem in the region.” Those samples were then subjected to a computer vision algorithm to obtain estimations of BMI for each politician. (Let’s leave aside for the moment that BMI is a highly imperfect means of determining a person’s body composition, despite its prevalence in the medical profession.)
He found that most of the politicians in the data set had quite high BMIs: 96 were severely obese (BMI between 35 and 40) while 13 were severely obese (BMI greater than 40). Only 10 boasted a BMI within the normal range, and none was underweight. Furthermore, when Blavatskyy compared his data with measures of corruption in those 15 states, he found a high correlation between the two. For instance, the Baltic countries (Estonia, Lithuania, and Latvia) and Georgia are deemed least corrupt, and their political leaders have the lowest median BMI. It wasn’t a perfect correlation, but Blavatskyy still concluded that this could be a viable method for assessing political corruption. However, he was careful to note that these results “do not necessarily imply that individual obese politicians are more corrupt than non-obese politicians.”
Citation: Olcay Cem Bulut, Dare Oladokun, Burkard Lippert, and Ralph Hohenberger, “for demonstrating that sexual orgasms can be as effective as decongestant medicines at improving nasal breathing.”
It’s a rare scientific paper that opens with an anecdote about the time Sigmund Freud let a pal perform experimental nasal surgery on him, but this is that paper. Chances are that you, like me, were unaware that back in 1897, a German otolaryngologist named Wilhelm Fliess—a close friend and confidant of Freud—came up with a theory of “reflex nasal neurosis,” positing that there was a physiological connection between the nose and the genitalia in humans, in the form of “genital spots located on the nasal turbinate.” There was never any scientific validity to Fliess’ theory but that didn’t stop Freud from referring a patient, whom he had diagnosed with the condition, for surgery. Yes, it ended badly, with “recurrent nasal bleeding and a disfigured nose,” per the authors.
Nonetheless, the authors wondered if perhaps there might be something to Fliess’ theory over a century later. Certainly not genital spots in the nose—that’s long been debunked—but perhaps sex could help unclog a stuffed nose. After all, studies have shown that physical exercise and hormonal changes can open up nasal airways. Why not sex? It’s kind of physical exercise.
Eighteen heterosexual couples (all health care workers or partners of health care workers) participated in this study, with measurements of nasal resistance and flow taken before sex to establish a baseline, right after climaxing, 30 minutes after orgasm, an hour after orgasm, and three hours after climaxing. Then they repeated the experiment the next day, with participants administering a nasal decongestion spray before having sex. (In a nod to gender equity, “the data were only obtained if both individuals [in a couple] experienced sexual orgasm.”)
Bulut et al. found that sex could indeed improve nasal congestion as effectively as nasal decongestant for up to 60 minutes, returning to baseline levels within three hours. Granted, a good 12-hour nasal spray would last much longer, but it’s less fun. And some people might experience adverse effects from nasal spray, so having a natural substitution method for congestion would be helpful. The authors hope that there will be further studies to investigate whether masturbation has a similar effect for singletons.
Citation: Ethan Beseris, Steven Naleway, and David Carrier, “for testing the hypothesis that humans evolved beards to protect themselves from punches to the face.”
Having a thick, full beard has been perceived as highly masculine in many cultures throughout the ages. But Beseris et al. thought there might be more to it than cultural preferences. Perhaps, they reasoned, human beards can provide protection in a fight. After all, the mandible (typically covered by a beard) is the most commonly fractured bone during a fight, and may have been a serious injury in eras lacking modern surgical treatments. They decided to test this hypothesis that thick facial hair serves to protect the face from blunt trauma resulting from strikes during a fight.
Since it wasn’t practical to take fully bearded skin samples from human cadavers, the team used skin samples from domestic sheep. Sheep fleece isn’t a perfect match for human hair, but it’s reasonably close. The samples were placed over a bone analog made of a fiber epoxy composite. One-third of the samples were furred, one-third were sheared, and one-third were plucked, and all were subjected to blunt force, via an anvil dropped from a specified height.
They found that the furred samples absorbed almost 30 percent more energy than the sheared and plucked samples, indicating “that hair is indeed capable of significantly reducing the force of impact from a blunt strike and absorbing energy, thereby reducing the incidence of failure,” the authors wrote in their paper. Assuming the same is true of human facial hair, “This may explain why facial hair is associated with high masculinity, social dominance, and behavioral aggressiveness, as it may function as a true indicator of invulnerability to facial injury.”
Citation: Alessandro Corbetta, Jasper Meeusen, Chung-min Lee, Roberto Benzi, and Federico Toschi, “for conducting experiments to learn why pedestrians do not constantly collide with other pedestrians.”
Pedestrian traffic is a fascinating case study in dynamic collective behavior, and hence holds much interest for physicists. This paper explores how human walkers continuously adjust the path of their trajectory as they encounter oncoming pedestrian traffic, in order to avoid collisions and maintain a comfortable personal space. “Not only is this scientific topic fascinating because of its connections with the physics of emerging complexity, pattern formation, and active matter, but it is also extremely relevant for its applications for the design, safety, and performance of civil facilities,” the authors wrote.
Physicists typically model such systems as interacting matter particles, with social forces acting on people in similar ways to physical forces. But modeling such a complex system is difficult, in part because of a dearth of high-quality experimental data. So Corbetta et al. set up a six-month pedestrian tracking experiment at thee train station in Eindhoven, The Netherlands, collecting data from October 2014 to March 2015 with the help of four overhead Microsoft KinectTM sensors. They collected over 100,000 pedestrian trajectories each day, amounting to about five million total, and used that data to build a better model for pedestrian interactions best described as “binary collision avoidance” (two people trying not to bump into each other). The authors believe their approach can be extended to more complex and denser crowd interactions.
Citation: Hisashi Murakami, Claudio Feliciani, Yuta Nishiyama, and Katsuhiro Nishinari, “for conducting experiments to learn why pedestrians do sometimes collide with other pedestrians.”
Murakami et al. decided to conduct an experiment to study the self-organized patterns that emerge in human crowds, like spontaneous lane formation, which provides a functional benefit to the collective system. The team hypothesized that, despite the prevalence of the aforementioned interacting particles model in such research, it can’t explain certain empirical observations. For instance, prior studies have found that interactions between pedestrians are influenced not by the current positions of their neighbors (distance-dependent physical force), but by anticipating their neighbors’ future positions. In other words, “pedestrians in a crowd are not just passively repelled by other pedestrians, but actively find a passage through a crowd by anticipating and negotiating with neighbors to avoid collisions in advance,” the authors wrote.
The researchers recruited 54 male university students and had them walk repeatedly along a straight corridor, with a waiting area on either end. They divided the participants into two groups walking in different directions, after assuming randomly selected starting positions. The twist: some of the participants were “distracted walkers,” instructed to peruse their mobile phones while strolling down the corridor. (The authors note that distracted walking is a major cause of pedestrian accidents.) Their movements were tracked via video recordings.
The team found that the addition of distracted walkers into the mix delayed pattern formation in the crowd, and led to more collisions between pedestrians, regardless of whether they were looking at their phones or not. “These results imply that avoidance maneuvers are normally a cooperative process and that mutual anticipation between pedestrians facilitates efficient pattern formation,” the authors concluded. “Our findings may influence various fields, including traffic management, decision-making research, and swarm dynamics.”
Citation: John Mulrennan, Jr., Roger Grothaus, Charles Hammond, and Jay Lamdin, “for their research study ‘A New Method of Cockroach Control on Submarines.'”
Submarines constitute a closed system when operating underwater, recycling the air via purification, for instance. That makes controlling cockroach populations on board submarines a unique challenge, since it’s impossible to fumigate with the usual insecticides without the toxic vapors lingering in the air. According to Mulrennan et al., both diesel and nuclear submarines employ carboxide fumigation for cockroach control (or at least it was standard practice in 1971, when this study was published.) But there weren’t any uniform regulations.
To explore alternatives, the researchers treated eight submarines with a commercially prepared aerosol called dichlorvos, making sure all cabinets, drawers, and void spaces were opened, and all ventilation systems turned off. After two hours, all the vessels were ventilated for an hour, and then crew members were allowed to reboard. Mulrennan et al. counted all the dead cockroaches right after ventilation to determine an initial kill count, and after 24 hours, any remaining roaches were flushed out. They also took air samples inside all the submarines to determine the concentration of dichlorvos before and after ventilation.
The results: dichlorvos proved to be 97-100 percent effective in controlling cockroaches on the vessels after 24 hours, and the air concentration of the chemical dissipated rapidly to safe levels within one to four hours. The treatment had no effect on any cockroach eggs, however, so the authors recommended re-treating submarines after two weeks (by which time any lingering eggs would have hatched). It’s worth noting that science has progressed significantly since 1971. The European Union banned the use of dichlorvos in 1998, and the US EPA has restricted its use since 1995, because of concerns of lingering toxic effects—such as a 2010 study showing an increased risk of ADHD in children.
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