Remember how you learned in BIO 101 that many fluids in the human body are normally sterile? And you know how you laugh with condescension when someone dares to question this dogma? After all, we know that the gut and the skin are full of microorganisms, but the lung? The bladder? This is inconceivable, heretical! Well, actually, this, like many other dogmas that seemed like God's word at the time, has been broken open by some very interesting research emerging from multiple laboratories around the world. I was first stopped in my tracks about a year ago, while listening to an NPR story in my car and learning that the number of bugs we carried on and in us was about 10-times greater than the number of our own cells. Then, in a farm house in Cornwall a couple of weeks ago, while on vacation, I read an article in an October 2009 issue of Eureka , The Times monthly science magazine, which once again made me ponder our sojourns in life, the bacteria that cohabitate with us. And fi...