The spoof accolade borrows its name from, but is not connected with, the world-famous Nobel Prize.
Created by the science magazine Annals of Improbable Research, the annual Ig Nobel Prize has been running since 1991.
It honors curious and “imaginative” discoveries and, like the original, has its own popular following.
The winning team of researchers, from Namibia, South Africa, Tanzania, Zimbabwe, Brazil, the UK and the USA, were attempting to see whether rhinos could be more safely transported when airlifted if they were suspended upside down.
As part of the experiment, led by Robin Radcliffe, a senior lecturer in wildlife and conservation medicine at Cornell University, the team sedated 12 black rhinoceroses in Namibia using aerial darts, bound their legs, and suspended them. They then measured their biomarkers for respiration and ventilation.
While the research method may sound bizarre, the findings of the experiment had important implications for conservation efforts.
An important discovery for conservation
Rhinos are often moved, usually by road but sometimes by air, around different parts of the African savannah to ensure the species maintains a diverse gene pool.
Conservationists have been using helicopters to move sedated rhinos across inaccessible terrain for about a decade – either placing them on their side a stretcher attached to the aircraft or hanging them upside down by their legs.
But until now little was known about which transportation method was better for rhino well-being.
Speaking to CNN about the experiment earlier this year, Radcliffe, the lead researcher, said the team had assumed hanging rhinos upside down in transit would be worse for their welfare and were surprised to learn the opposite was true.
The rhinos were found to have higher blood oxygen levels when suspended upside down.
“We were anticipating that the rhinos would fare worse hanging upside down,” he said at the time.
The study, which was published in January in the Journal of Wildlife Diseases, began in 2015 and involved 12 rhinos weighing between 1,770 and 2,720 pounds each.
Among the other scientists honored this year were a group of researchers who looked into the bacteria that live on discarded chewing gum on sidewalks, and researchers who discovered orgasms can clear nasal congestion in humans.
Last year, the Ig Nobel Prize was given to a team of Austrian and Japanese scientists who put an alligator in a helium-filled box and made it make noises.
Another experiment, which found that narcissists can be identified by their eyebrows, was also honored.
CNN’s Rebecca Cairns and Rob Picheta contributed to this report.