microbiome

Many scientists and anthropologists (though not all) believe that long before humans came on the evolutionary scene, microbes ruled the earth. When humans finally showed up they had to get with the program, which was symbiosis. The deal was struck that some microbes could use us as walking condominiums in which they could live safe and sound, and in turn they would protect us against other invading microbes and perform a variety of other tasks that scientists are busy discovering.