TIL that a 2012 study found 1,458 “new to science” bacteria species in our belly buttons. People’s bacterial profiles are unique, like fingerprints, and can be used in the same way. One person had a bacterium only ever found in Japanese soil," where he had never been. User ifthisthenthat99, in the Today I Learned (TIL) subreddit, 28 Aug 2020
TIL In 2012, scientists found 1,458 new species of bacteria living in the belly button. Everyone's belly button ecology is unique like a fingerprint, and one volunteer's belly button harbored bacteria that had perviously been found only in soil from Japan...where he had never been. User caleom, in the Today I Learned (TIL) subreddit, 26 May 2014
A Jungle in There: Bacteria in Belly Buttons are Highly Diverse, but Predictable User jeargle, in the Biology subreddit, 13 Nov 2012