Right now in the scientific world, it’s time for mammals to shine – literally.
Researchers are building a growing (and dazzling) list of fluorescent mammals, and a new addition, a cuddly jumping rodent called Springhare, has just jumped into the spotlight, with its brown fur glowing in swirling pink and orange disco patterns below ultraviolet (UV) rays.
Scientists have recently discovered the pink glow of spring specimens in museum specimens and in live animals in captivity. They found that the striking fluorescent colors of springhares are “fun and vivid,” forming patterns that are very diverse “relative to the biofluorescence found in other mammals,” the new study wrote.
Related: Bioluminescent: A great gallery in the dark
Biofluorescent animals have fur or skin that absorbs and redirects light of short waves as a longer wavelength, changing its color. Many species of invertebrates, reptiles, amphibians, fish and birds are fluorescent, but in recent years scientists have also discovered the fluorescence of mammals that are active at dusk or at night, such as flying squirrels, opossums and platypuses.
Springhares, the only members of the rodent genus Pedetidae, are also nocturnal. There are two types – P. capensis i P. surdaster – is found in South Africa and in parts of Kenya and Tanzania. They have short front and powerful hind limbs like jumping kangaroos. According to research, both types shine.
Researchers discovered the hidden glow of springhares as they searched for signs of biofluorescence in flying squirrels and other sliding mammals in the Field Museum collection in Chicago, said study lead author Eric R. Olson, an associate professor of natural resources at Northland College in Ashland, Wisconsin. Their search led them to scaly squirrels, which did not glow, and then to a nearby drawer where the squirrels kept their closest living relatives: spring.
“We saw this pink-orange biofluorescence in drawers, and it was an exciting moment,” Olson said in a Live Science email. “Seeing something like this, probably for the first time – really sparked a fire of curiosity.”
A total of 14 museum specimens and six captive-bred springs were inspected – five alive and one deceased. Under UV light, the dark brown fur on Springhare’s back lit up in streaks, spots, and bright pink spots.
“Both male and female samples fluoresced in the same regions and with the same intensity,” the study authors reported.
The luminous colors of Springhares produce organic compounds called porphyrins, according to the study. Springhares probably get their pink glow from coproporphyrins and uroporphyrins, which scientists have isolated from animal fur, said study co-author Michaela Carlson, an assistant professor of chemistry at Northland College. These two compounds fluoresce in the yellow, orange, or red region visible spectrum “depending on the conditions,” Carlson said in an email to Live Science.
And unlike other glowing mammals, the bright patterns of Springhares were very different among individuals, and in some they were even uneven.
“The most intense fluorescent areas were mostly around the back squares,” Carlson said. Initially, scientists wondered if springhares applied color-changing porphyrins to their fur by grooming, “since porphyrins can be excreted through urine and feces,” Carlson said in an email. The researchers eventually dismissed that hypothesis because they could not wash the porphyrins from the spring fur. Visible light breaks down these chemicals, “so potentially part of the samples is a result of this exposure,” Carlson explained.
Another possibility is that sampling can serve as a kind of camouflage, creating a visual “noise” that could protect the spring from predators that are sensitive to UV radiation, Olson said.
“However, there is also a good chance that this trait plays no role in interactions within or between species,” he added. “Further research is needed.”
Most – but not all – known mammals that show biofluorescence are most active in low-light environments, suggesting that biofluorescence may be a more widespread characteristic among species that are outdoors in the dark or at night. “But a thorough assessment of a wider range of species is still needed to determine if it is actually more common in this group or not,” Olson said.
The findings were published online Feb. 18 in the journal Scientific reports.
Originally posted on Live Science.