On the microbial level, a person's underarms are akin to lush rain forests brimming with diversity,and that's a good thing,according to a new "topographic map" of human skin. Most of our skin is like an arid desert, said study co-author Julia Segre"¦ "But as you walk through this desert you encounter an oasis, which is the inside of your nose," she said. "You encounter a stream, which is a moist crease. [These] areas are like habitats rich in diversity"
The bacteria were taken from sites that were categorized as dry (like the forearm), moist (like the aforementioned armpit and the bellybutton), and oily (like the space between the eyebrows). They found a far greater number of bacterial species than expected belonging to 205 different families, and also discovered that the different skin "ecosystems" hold very different bacterial strains. That means strangers often share the same bacteria living on their underarms, even as two separate sites on the same person contain wildly different bacteria
