The Belly Button Biodiversity project recently began taking DNA samples from people's navels to find out what bacteria is living within. Of the roughly 1,400 bacterial strains discovered thus far, at least 662 of them are completely unknown.
We wrote about the North Carolina State project a couple months back, and now the initial results on their first human investigations are in. The researchers swabbed the bellybuttons of 95 volunteers, and then used the 16S ribosomal RNA of the various bacterial strains to identify them. Using that method, they found they couldn't even identify the family, let alone the species, of hundreds of microbes, which strongly suggests they were previously unknown.