This has happened to me so many times but my memory not being what it was or what yours is.. I had to wait for an example. I didn’t have long to wait..
Just reading NYT – http://www.nytimes.com/2011/04/21/science/21gut.html?_r=1&hp
“In the early 1900s, scientists discovered that each person belonged to one of four blood types. Now they have discovered a new way to classify humanity: by bacteria. Each human being is host to thousands of different species of microbes. Yet a group of scientists now report just three distinct ecosystems in the guts of people they have studied.
The research team, led by Beer Pork …”
Sorry mis-read that – should have been Peer Bork!!