Nocturnal lemurs called aye-ayes are true champions of nose-picking.
A new video offers the first evidence that these primates stick their fingers up their snouts and lick off the snot. They don’t use just any finger for the job, either. Aye-ayes mine for mucus with the super-long middle finger they normally use to pluck tasty grubs from tree bark. CT scans of the inside of an aye-aye’s head suggest that this spindly digit can poke all the way through the animal’s nasal passages to reach its throat.
“I was really surprised,” says Anne-Claire Fabre. She’s a biologist at the National History Museum of Bern in Switzerland who captured the video. Fabre filmed a female aye-aye named Kali picking her nose at the Duke Lemur Center in Durham, N.C. An aye-aye is about as big as a house cat. But its clawed middle finger is some eight centimeters (more than three inches) long. Kali was shoving almost the entire digit up her nose.
This got Fabre and her colleagues curious. How many other primate species have been caught with their fingers in their nostrils? A search of past studies and online videos revealed that 11 other species of primates are known to pick their noses and snack on the snot. The team shared those findings online October 26 in Journal of Zoology.