Scientists think long-fingered lemurs – who like picking their noses – might hold the secret as to why other primates do it.
And yes, by other primates, we do mean humans.
Aye-ayes (also known as long-fingered lemurs) belong to the strepsirrhine primates, and are native to Madagascar (but, before you ask, King Julien from the film franchise is not one of them).
It’s the world largest nocturnal primate with teeth like rodents, and a particularly long and thin middle finger which makes up around two-thirds of its entire hand length.
This finger usually finds food inside wood. But, it’s now been recorded for the first time using this digit to dig around in its nostrils and then lick its fingers clean – an action which was “impossible not to notice”, according to one researcher.
Lead author Anne-Claire Fabre, a scientific associate at the Natural History Museum in London said: “This was not just one-off behaviour but something that it was fully engaged in, inserting its extremely long finger a surprisingly long way down its nose and then sampling whatever it dug up by licking its finger clean.”
And it’s far from alone. At least 12 other primate species have been found doing the same thing: picking their noses and eating the mucus they find there.
While it may not be the most delicious habit (and deeply frowned upon in human circles), the findings published in the Journal of Zoology could yet explain why it’s a habit we just can’t kick.
Fabre said: “There is very little evidence about why we, and other animals, pick our nose.
“Nearly all the papers that you can find were written as jokes.
“Of the serious studies, there are a few in the field of psychology, but for biology there’s hardly anything.
“One study shows that picking your nose can spread bacteria such as Staphylococcus, while another shows that people who eat their own snot have fewer dental cavities.”
Researchers have already used a CT scan to look inside the skull and hand of an aye-aye specimen at the museum, mimicking the action of the lemurs when they, um, go digging for gold.
By putting the middle finger in the nostril, researchers found the finger is likely to stretch all the way down the primate’s throat.
Roberto Portelz Miguez, senior curator in charge of Mammals at the Museum, said: “We hope the future studies will build on this work and help us understand why we and our closest relatives insist on picking our noses!”
Could it be for health reasons? Previous research has suggested it could help boost our immune system by exposing our body to bacteria.
But these researchers believe it is simply a case of the animal enjoying the texture, crunchiness and saltiness...