Australian mammals and marsupials including wombats ‘glow in the dark’ under ultraviolet light, according to a team of scientists.
After a US study in October found that platypuses are biofluorescent, researchers from Western Australian Museum borrowed a UV light to verify the claim.
Not only were they able to confirm the findings of the earlier study, but also discovered that many other marsupials and mammals also glow in the dark.
Researchers don’t yet know why these creatures – including wombats and bilby – are biofluorescent, but believe it could be to help them spot fellow members of their own species, as the bulk of those glowing in the dark were nocturnal.
Wombats are just one of the species at the Western Australian Museum found to be bioflourescent under UV light
In October, US scientists from Northland College discovered – accidentally – that if you shine a UV light on a platypus it will glow green in the dark.
This is a form of biofluorescence – something that has long been known about in plants, insects and sea creatures – but until now had not been seen in mammals.
Inspired by the US discovery, Kenny Travouillon, a palaeontologist from Western Australia Museum, found a UV light and used it on specimens in the museum.
‘We borrowed it and turned off the lights in the collection and looked around for what was glowing and not glowing,’ Dr Travouillon told ABC News.
They started by checking the platypus to verify the findings of the US study and they found they ‘were all glowing, which confirmed the research.’
After confirming the US research Travouillon looked to marsupial moles and wombats – finding they also started to glow under UV light.
‘We did on the carnivorous marsupials and they did not glow at all,’ he told ABC, adding this could be because if prey can see UV light the predators couldn’t hide.
Travouillon, who is curator of mammalogy at the museum, has tried the UV light on two dozen mammal species – not an extensive search, but an overview.
He said about a third of them were found to glow under UV light including the platypus, echidna, bandicoots, bilbies, possums and some bats.
‘After platypus was shown to glow under UV light, couldn’t resist trying bilbies… their ears and tails shine bright like a diamond,’ he wrote on Twitter.
A bilby specimen stored at the Western Australian Museum under UV light was found to have glowing ears and fur by researchers
Bioflourescence is triggered when a living creature is able to absorb enough high energy radiation – such as UV light – that it can emit it at a lower frequency.
‘There are compounds in lots of different animal parts that do seem to fluoresce, so it’s not surprising to find there may be other chemical compounds in other things like fur that fluoresce,’ wildlife forensic scientist Greta Frankham told ScienceAlert.
Many of the creatures found to glow under UV light are also nocturnal, the team behind the latest discovery explained.
This included bilbies, an endangered desert dwelling species that likes eating scorpions – another animal that glows under UV light.
Other nocturnal creatures found to glow in the dark included the wombat and the bandicoot – but for humans to see the glow we need an intense UV light source.
Platypuses have been found to glow green under UV light. It was an accidental discovery by researchers at Northland College in the US
This prompted Travouillon to speculate that the creatures can see much more than we are able to see.
However, Michael Bok, an expert from Lund University in the evolution of vision, said it was unlikely there was any visual signal responsible for animals evolving this trait.
‘Be careful about applying ecological or visual relevance to this. Many biological materials fluoresce, but the lighting conditions where it is visible to anything are incredibly unnatural. It is extremely implausible that this is a visual signal,’ he said.
Bok shared a mock research paper with the words ‘insert animal’ to illustrate that so many creatures have been shown to glow under UV light that more work is needed to understand why.
Doctoral student from the University of Exeter, George Hancock joked: ‘Honestly you could parade around a zoo with a black light at this point and just generate papers. Why do they glow, we don’t know? Cause apparently that’s enough.’
The original US paper on biofluorescence in the platypus has been published in the journal Mammalia.
NOCTURNAL ANIMALS REST DURING THE DAY AND ARE ACTIVE AT NIGHT TIME
A new study has found that some animals rely on the starry sky to navigate at night. Frogs are among these animals (file photo)
Nocturnal animals rest during the day and are active at night.
This means they hunt, mate and perform other necessary survival activities without the help of the sun.
Many nocturnal animals have built-in bodily functions that help them survive during nighttime hours when it might be difficult to see.
For example, some nocturnal animals’ eyes are larger, which gives them the ability to function satisfactorily even in the dark.
Additionally, some nocturnal animals have extremely sensitive ears that can help them defend themselves in dark environments.
Lastly, some have heightened senses of smell, touch and taste to help them perform better during the nighttime.