The backyard dormouse glows below UV gentle – however we don’t know why

Backyard dormice might not appear significantly flamboyant. In truth, the small, brownish-white rodents spend a lot of their life attempting to not be seen. However new analysis reveals that below the appropriate gentle, these dormice shine with brilliant pinks and greenish-blues.

Photoluminescence happens when a substance absorbs photons of ultraviolet gentle and re-emits them at longer wavelengths. It happens in lots of marine animals, some bugs and millipedes, and within the plumage of some birds. It encompasses two processes: fluorescence, when photons are re-emitted nearly instantly, and phosphorescence, which might final for a number of minutes.

After seeing current research that discovered photoluminescence in nocturnal mammals akin to flying squirrels and springhares, Grete Nummert at Tallinn Zoo in Estonia puzzled if backyard dormice (Eliomys quercinus) would show photoluminescence too. She made a high-stakes wager together with her colleague: “The losing one would bake a cake,” Nummert says.

She and her colleagues gathered a number of of the backyard dormice stored at Tallinn Zoo whereas they have been sleeping, and shone ultraviolet gentle on the animals by way of a yellow filter.

A lot of the mice’s fur shone a brilliant reddish pink. With out the yellow filter, the fur seems extra of a purple color. The toes and the nostril, alternatively, have been bluish inexperienced.

To develop their observations, the researchers examined dormice saved on the Estonian Museum of Pure Historical past below the UV gentle. These previous specimens additionally displayed photoluminescence, although their colors had light over time.

Nummert, who says the cake she received was “delicious”, isn’t certain but why the dormice are photoluminescent. Some parrots use photoluminescence to sign to potential mates. Springhares have a patchy photoluminescence which will assist them camouflage amongst crops that replicate gentle in the same method, relying on what sort of creatures are wanting.

It’s additionally potential that the photoluminescence exhibited by dormice and different rodents is only a by-product of one thing they eat, or another pure course of. It isn’t even clear if the dormice can understand these colors themselves — people actually can’t with out the assistance of UV gentle.

“There is a whole world we cannot see,” Nummert says. “Animals perceive the world differently from us.”