Deep space and deep sea are commonly held to be two of the regions about which we know least. But scientists have discovered a third and it lies much closer to home.
Towards the end of 2012 a group of North Carolina-based researchers published the results of experiments in which they swabbed 60 belly buttons and identified a total of 2,368 species of bacteria. A Jungle in There: Bacteria in Belly Buttons are Highly Diverse, but Predictable asserts that, “The belly button is one of the habitats closest to us, and yet it remains relatively unexplored. We analyzed bacteria and arachaea [single-celled microorganisms] from the belly buttons of humans from two different populations sampled within a nation-wide citizen science project.”
It seems that people’s individual profiles are bacterially unique. The follow up Belly Button Biodiversity (BBB) project goes on to say:
“The belly button has captured the imagination for centuries – it’s made us giggle, it’s made us blush, it’s made us turn our heads in horror (just do a Google image search for belly buttons). It’s the portal through which we were connected to our mothers; and it’s the physical reminder of our evolutionary past.”
And, according to Claire Cronin, a doctor who wrote “Clean Your Belly Button” for the web site of the Massachusetts Medical Society (17 November 2010):
“There is a surprising lack of awareness on the public’s part as to what can accumulate in a belly button and therefore what must be removed. These collections can take the form of a hair ball or a blackened wax cast of the umbilicus. Lint from clothes can accumulate just as it does in the dryer. Some entrepreneurial folk actually save and display their navel lint in jars. Unfortunately, the volume of material increases as the patient ages and just like their arteries, can harden. I like to think of it as a cache of a lifetime of little treasures.”
In 1968 on Hokkaido, Japan’s northernmost island, the town of Furano inaugurated the Belly Button Festival where dancers turn their heso (belly button) into a face, using paint, and perform dances with special costumes and props. The festival takes place in summer since Hokkaido is known for inhospitable winters with Siberian winds bringing the temperature down to a belly-button puckering minus 30 degrees. Navel-gazing is clearly a scientific past-time.