Although individuals can harbour up to a thousand different types of microbes, more than 90% of these belong to one or other of two groups, called Bacteroidetes and Firmicutes.

• 虽然个体差异能使人带有一千多种不同的微生物，但是其中百分之九十以上都归属于两个门类，即拟杆菌门和壁厚菌门。