February 13, 2007 -- Hundreds of Bacterial Species Live On Your Skin

Three years ago, genome pioneer Craig Venter sailed the Sargasso sea and returned with 1,800 species of microbes, including 150 never before seen. An impressive haul. But last week, scientists in New York announced that if you want to discover new and interesting bugs, you need travel no further than your own forearm.  The researchers, at the NYU School of Medicine, identified 182 species of bacteria, including a dozen new ones, in swabs taken from the arms of six healthy volunteers. Their study marks the first full-scale expedition to catalog the biota that calls the human epidermis its home.

The microbes that live in and on our bodies outnumber our own cells 10 to 1. So they’re an important part of our personal ecology. And it turns out the zoo of bacteria on one person’s skin is very different from the zoo on someone else’s. Almost three-quarters of the species identified were unique to an individual. And only four species were found on all six subjects.  For the record, the researchers took their samples from the subjects’ forearms because that way no one had to undress.  So who knows what exotic life forms may be waiting for discovery just behind your knees.