It’s a biological mission that began with a chance encounter with a lemur who was picking his nose.
It wasn’t just any lemur; an aye-aye was filmed by Professor Anne-Claire Fabre of the University of Bern burying her elongated finger in her nostril.
“I wanted to know where this finger is going?” she told the BBC.
The meeting at the Duke Lemur Center in the United States led Professor Fabre and her colleagues to question the evolutionary origins of the habit.
Aye-ayes are nocturnal primates found only in Madagascar. They are famous for their weird, thin and long fingers, which they use to fish for larvae from branches.
“He was entering the full length and, [when you look at] the length of his head, it was like – where is he going? “he recalled.” I was wondering – is he inserting it into his brain? It was so strange and it seemed impossible. “
The question intrigued prof. Fabre that she conducted a 3D anatomical analysis of the aye-aye head, to reconstruct the seemingly impossible anatomy of the nose pinch.
“It was going into the breast and from the breast to the throat and mouth,” she explained.
With her colleagues, Prof. Fabre looked in the scientific literature for evidence of other animals that tickle their noses. In a study published in the Journal of Zoology, the team found 12 examples of primates caught pinching their noses.
As Professor Fabre, who is also a mammalian curator at the Natural History Museum in Bern, pointed out, there are very few studies that aim to understand why an animal, including humans, may have developed the urge to pinch its nose.
‘We really think this behavior is underestimated because it is really seen as a bad habit,’ explained Professor Fabre. Studies investigating behavior in people have shed light on how common the habit is, revealing that most humans often touch their noses but are reluctant to admit it.
There are some studies looking at the cons – and possible benefits – of nose picking. Some have pointed to its role in spreading harmful bacteria. But there is at least one study that suggests that taking off your nose and eating it might actually be healthy for your teeth, as people who clean their noses reported fewer cavities.
One study encouraged further research by suggesting that nasal mucus ingestion could play an important role for the immune system, due to the immune proteins in the mucus.
Basically, Professor Fabre says it is likely to have evolved for a reason and should be studied.
“We have no idea of its functional role,” he told the BBC. “And it could be beneficial.”
Rather than just being disgusting, it could have benefits for some species and as so many animals seem to share this habit, Professor Fabre said: ‘I think we really need to investigate it.’