Sept. 10 (UPI) -- The recipients of the 2021 Ig Nobel Prizes include researchers who experimented with upside-down rhinos, analyzed the bacteria in discarded gum and studied the ways cats communicate with humans.
The prizes, awarded by science magazine Annals of Improbable Research, were announced Thursday at the 31st annual Ig Nobel Prize ceremony.
The Biology Prize went to Swedish researcher Susanne Schotz, who analyzed the variations in cat vocalizations while communicating with humans.
The Ecology Prize was awarded to a team of Spanish and Iranian researchers who used genetic analysis to compare the different species of bacteria found on discarded chewing gum recovered from paved surfaces in various countries.
The Chemistry Prize went to a team of researchers from Germany, Britain, New Zealand, Greece, Cyprus and Austria who used chemical analysis to test whether bodily odors created by a movie theater audience could be used to track incidents of violence, sexuality, drug use and profanity in films.
The Economics Prize was presented to Pavlo Blavatskyy, who led a study that suggests the obesity of a country's politicians can be used to indicate the level of corruption in the country.
The Medicine Prize was awarded to Olcay Cem Bulut, Dare Oladokun, Burkard Lippert and Ralph Hohenberger for their study demonstrating that sexual orgasms are as effective as decongestant medicines at improving nasal breathing.
The Peace Prize was given to a team of U.S. researchers who tested the hypothesis that humans evolved beards to protect themselves from punches to the face.
The Physics Prize went to a team of researchers who conducted experiments to learn why pedestrians do not constantly collide with other pedestrians, while the Kinetics Prize went to a different team of researchers who looked into why pedestrians sometimes do collide with other pedestrians.
The Entomology Prize was awarded to John Mulrennan Jr., Roger Grothaus, Charles Hammond and Jay Lamdin, the authors of research study "A New Method of Cockroach Control on Submarines."
The Transportation Prize was given to a team of Namibia, South Africa, Tanzania, Zimbabwe, Brazil, Britain and U.S. researchers who conducted experiments to determine whether it is safer to airlift a rhinoceros with the animal upside-down.