In October, research revealed that the fantastically weird, duck-billed platypus glows blue-green under ultraviolet light. Now, tests by scientists at the Western Australian Museum (WAM) may have added more marsupials and mammals to the list of critters with fluorescent fur, reports Rachel Edwards for the Australian Broadcasting Corporation (ABC News). Even a few select bits of the famously feisty Tasmanian devil showed up glowing when conservation technician Jake Schoen of the Toledo Zoo tested a special UV camera on the zoo’s resident devils, Spiderman and Bubbles, reports Cara Giaimo for the New York Times.
WAM curators initially went to shine a black light on the platypuses in their natural history collection to check on the creature’s purported ultraviolet (UV) glow. Tests swiftly verified that WAM's taxidermied platypuses did indeed glow, which made Kenny Travouillon, the museum's curator of mammalogy, wonder if there might be other unexpected ultraviolet biofluorescence lurking in their collections.
Lo and behold, Travouillon’s preliminary investigations suggest bare-nosed wombats, endangered marsupials called bilbies, some bats, echidnas, hedgehogs and porcupines also sport some ultraviolet highlights, according to the Times.
The Toledo Zoo is excited to report the first documented case of biofluorescence in Tasmanian devils!— Toledo Zoo (@ToledoZoo) December 5, 2020
Biofluorescence refers to the phenomenon by which a living organism absorbs light and reemits it as a different color.
#ToledoZoo #Biofluorescence #TasmanianDevils pic.twitter.com/IxhXvHzqMl
As soon as Travouillon posted photos of the glowing animals to Twitter he got a message from a researcher at Curtin University who offered to bring in forensic light equipment for more tests. Travouillon tells ABC News that those additional tests suggested some animals may even reflect other parts of the non-visible light spectrum in addition to UV light.
"We will look at various marsupials to see if there is a pattern with nocturnal mammals, a lot more research coming in the future," Travouillon tells ABC News.
More research is needed to more firmly establish the ranks of glowing mammals, and it’s entirely unclear what, if any, function the biofluorescence may serve.
"It is possible that it is actually taking the ultraviolet light that is more prevalent at dusk and dawn, making it kind of disappear so that any predators that are keying in on ultraviolet light can't see the platypus because it is kind of cloaking itself," Sarah Munks, a biologist who studies the platypus at the University of Tasmania, tells ABC News. "All the work done on other species suggests that it is an ancient form of camouflage. It could just be one of these ancestral traits, like humans have remnant tails,” says Monk.
Michael Bok, a visual systems biologist at Lund University who was not involved in any of the new research, tells the Times it’s unlikely that these animals appear to one another as they do in the otherworldly photos. “It would be incredibly surprising,” Bok tells the Times, if these species “could make out these fluorescent patterns in any sort of natural lighting environment.” Bok also noted the fluorescence of human fingernails and teeth, which doesn't attract scientific attention.
But even if all this UV fluorescence is just biological happenstance, the extra moment in the UV limelight may provide added support for wildlife conservation. "If it's quirky and interesting like that it will always get people's attention,” Travouillon tells ABC News.
Schoen tells the Times the photo of his glowing Tasmanian devils has introduced people to the animals for the first time, with some writing online that they “didn’t even know that it was a real animal.” The devils’ biofluorescence “may just be a coincidence,” he tells the Times, “but it’s certainly a lot of fun.”