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.