Bacteria Divide People Into 3 Types, Scientists Say
20th April 2011
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.
Judging by recent history, there will soon be a dating service to match people by their gut type.