Science news in brief
Meet the newest member of the fluorescent mammal club
Platypuses do it. Opossums do it. Even three species of North American flying squirrel do it. And, breaking news: two species of rabbit-size rodents called springhares do it. That is, they glow under black light, that perplexing quirk of certain mammals that is baffling biologists and delighting animal lovers all over the world.
Springhares, which hop around the savannahs of southern and eastern Africa, weren’t on anyone’s fluorescence bingo card. Like the other glowing mammals, they are nocturnal. But unlike the other creatures, they are Old World placental mammals, an evolutionary group not previously represented. Their glow, a unique pinkish-orange the authors call “funky and vivid,” forms surprisingly variable patterns, generally concentrated on the head, legs, rear and tail.
Fluorescence is a material property rather than a biological one. Certain pigments can absorb ultraviolet light and re-emit it as a vibrant, visible colour. But mammals, it seems, don’t tend to have these pigments. A group of researchers, many associated with Northland College in Ashland, Wisconsin, has been chasing
down exceptions for the past few years – ever since one member, biologist Jonathan Martin, happened to wave a UV flashlight at a flying squirrel in his backyard. It glowed eraser pink. The researchers then went to the Field Museum in Chicago. When the team tried a drawer that housed preserved springhares, they beamed back. “We were equal parts shocked and excited,” said Erik Olson, an associate professor of natural resources at the college and an author of the new paper, published in Scientific Reports. Over the next several years, the researchers examined 14 springhare specimens from four countries, some male and some female. All showed fluorescence – many in a patchy pattern, which was unique among mammals they’ve studied, Olson said.
Chemical analysis of springhare hair found that the fluorescence comes largely from a set of pigments called porphyrins, which have also been found to cause this effect in marine invertebrates and birds, said Michaela Carlson and Sharon Anthony, chemists at Northland College who worked on the paper. But the biggest question is: why?
The springhare findings in particular provide some avenues for exploration. There is a possibility that fluorescence helps animals hide from predators with UV-sensitive vision, by absorbing wavelengths that would otherwise be brightly reflected and emitting less visible ones. In that case a patchy pattern like the springhares’ might be another asset, Olson said. Cara Giaimo
Hear the sound of a 17,000-year-old seashell horn
In 1931, researchers working in southern France unearthed a large seashell at the entrance to a cave. Unremarkable at first glance, it languished for decades in the collections of a nearby natural history museum.
Now, a team has reanalysed the roughly foot-long conch shell using modern imaging technology. It’s an extremely rare example of a “seashell horn” from the Paleolithic period, the team concluded. And it still works – a musician recently coaxed three notes from the 17,000-year-old shell. “I needed a lot of air to maintain the sound,” said Jean-Michel Court, who performed the demonstration and is also a musicologist at the University of Toulouse.
The Marsoulas Cave, in the foothills of the French Pyrenees, has long fascinated researchers with its colourful paintings depicting bison, horses and humans. It’s where the enormous tan-coloured conch shell was first discovered, an incongruous object that must have been transported from the Atlantic Ocean, over 150 miles away.
Only in 2016 did researchers begin to analyse the shell anew. Artefacts like this conch help paint a picture of how cave dwellers lived, said Carole Fritz, an archaeologist at the University of Toulouse who has been