Subsequent research by Australian scientists revealed that other animals also glow under UV light, including marsupials, the first accidental discovery by American scientists that platypuses glow.
After reading a publication in Mammalia about the platypus’s surprising nocturnal glow, Dr. Kenny Travouillon from the Western Australian Museum did a little experiment.
As curator of mammals, he had many dead mammals in his care, so he decided to apply UV light to some of them to see if they would glow in the dark.
A surprising number of them do.
Travouillon posted updates on the results on the museum’s social media platforms. His research shows that in addition to echidnas, the platypus’ closest living relative, other creatures that also glow under UV light include opossums, wombats, bilbies,, and several Australian bats.
Subsequently, other people presented their research, which included sightings of eastern bandicoots and bright Tasmanian sugar gliders.
Although it has long been recognized that some insects and marine animals exhibit fluorescence, it was not previously known that many Australian mammals also exhibited this phenomenon. However, not all native Australian mammals have this trait.
For example, none of the examined members of the Travouillon family of kangaroos showed any color response to UV radiation, while several other animals remained similarly dark.
Based on Travouillon’s tweets, Curtin University academics contacted him about collaborating on a more thorough investigation. They want to explain why some marsupials have this special trait while others don’t.
But in the meantime, Travouillon gave IFLScience access to his working hypotheses. He tried shining a light on other predatory marsupials, such as Tasmanian devils and quolls, but none of them glowed in response.
He speculates that this could be because, especially at dusk, a light show of this kind would alert potential victims to their existence. Small mammals can glow in peace, as predators often suffer from color blindness, although prey species may seem to lose even more due to lack of vision.
Because kangaroos live in groups, they can see each other without the need for color. During the mating season, solitary animals must be able to identify each other, says Travouillon. However, it is not clear how this idea explains the diversity among particularly social bats, and Travouillon stresses that more research is needed before a comprehensive explanation can be provided.
Since platypuses close their eyes when submerged, Travouillon further questions whether they use their glow as a mating signal. Rather, they believe that it is probably a remnant of some distant ancestor, similar to a human tail.
Travouillon observed that the species he studied showed no signs of light production per se, while some bioluminescent animals did. This makes it more likely that they are fluorescent: “I think their fur reflects UV light in some way, probably its chemical composition.”
Curiously, this common marsupial trait went unrecognized until now, as scientists have known—since 1983—that UV radiation causes North American opossums to have hallucinogenic hues.
Recent discoveries of biofluorescence in Australian mammals represent an exciting advance in our understanding of animal behavior and adaptation.
Dr. Kenny Travouillon’s research has revealed that not only platypuses glow under UV light, but several other marsupials, including echidnas, opossums, and wombats, share this interesting trait. This finding expands our knowledge of mammalian biology and highlights the rich diversity of adaptations present in Australia’s unique fauna.
Collaboration between scientists and researchers indicates a growing interest in uncovering the causes of this phenomenon. While the biofluorescent abilities of some marsupials may serve specific ecological or social functions, such as communication during mating or improving survival against predators, the absence of this trait in others raises important questions about evolutionary pressures and adaptations.
The hypothesis that some animals may not exhibit fluorescence due to their social behavior or predatory status opens up avenues for further investigation.
Moreover, the discovery that many mammals have this trait, previously thought to be limited to insects and marine life, suggests that there are likely many other undiscovered aspects of mammalian biology waiting to be explored.
This underscores the need for continued research in this area, particularly understanding how environmental factors influence the development of such features.Â
Overall, Travouillon’s findings challenge us to reassess the complexity of animal communication and adaptation and remind us that nature often holds surprises that challenge our existing knowledge.
As scientists delve deeper into this field, we can expect more revelations that will enhance our appreciation for the complex relationships between animals and their environments.