Scientists have discovered why people pick their nose and eat the snot.
The disgusting act may be frowned on by human beings, but one type of primate has specialised fingers for doing exactly that.
Scientists found picking your nose can spread bacteria such as Staphylococcus. Another study showed people who eat their own snot have fewer dental cavities.
The long-fingered lemur uses its lengthy digits to stick up its nostrils before it licks its finger clean.
it is among a dozen primates, including humans who pick their nose and eat the mucus, according to the study.
HullLive reports that their findings, published in the Journal of Zoology, could shed some light on the evolution and the possible functional role of nose picking across all these species.
Lead author Anne-Claire Fabre, a scientific associate at the Natural History Museum in London, 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.”
The aye-aye belongs to a category of species known as strepsirrhine primates and is native to Madagascar.
Also known as the world’s largest nocturnal primate, this lemur has rodent-like teeth and a specialised long and thin middle finger.
The aye-aye’s fingers make up about 65% of the length of the hand – which the creature uses to locate food inside wood by tapping on it and then extracting small grubs.
But researchers also observed something else about the aye-aye: the lemur uses its longest finger to pick its nose.
Ms Fabre said: “It was impossible not to notice this aye-aye picking its nose.
“This was not just a 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!”
To better understand this behaviour, the research team used an imaging technique known as a CT scan – usually used by medical professionals to obtain internal images of the body – to look inside the skull and hand of an aye-aye specimen at the museum.
Their aim was to reconstruct the position of the middle finger inside the nasal cavity.
Findings suggested that the finger is likely to descend all the way into the throat.
The Mirror reported in 2018 how parents who catch their children picking their noses and tell them off for it because it's gross.
It may be unhygienic and a bit embarrassing if your children decide to do it in a public place and most mums and dads think it is relatively harmless.
But it turns out picking your nose could spread a dangerous bacteria which causes pneumonia, new research warns.
The study, published in the European Respiratory Journal, showed the transmission of pneumonia can occur through contact between the nose and hands when exposed to the bacteria.
Researchers found bacteria spreads at the same rate whether dry or wet, or whether people pick or even just rub their noses.
Pneumonia is a major cause of death around the world and is estimated to be responsible for 1.3million deaths in children under five years of age.
