Figure 19.20: The Human Body’s Microbiome Is Critical to the Maintenance of Health Surveys of the human microbiome have shown that this diverse community includes thousands of microbial species that are adapted to grow in or on various parts of the human body. Although it has become clear that the composition of this microbiome is closely associated with many aspects of human health, most of the component species are poorly characterized and remain largely unstudied by biologists. What has become clear is that, although the “subcommunities” in different parts of the body share similarities, each is a site-specific assemblage of many distinctive species.