Microbes have existed for billions of years, but though we felt their effects, scientists only began to learn about them in the last hundred years. Our knowledge of the microbial world has blossomed in the 21st century and is expanding every day. Rob DeSalle (The Brain) and Susan Perkins are curators at the American Museum of Natural History, and Welcome to the Microbiome is an excellent introduction to this exciting scientific field, clearly written for a general audience and illustrated with fine black-and-white drawings by Patricia J. Wynne.
Your body is home to about "ten thousand different species of microbes... approximately the same number as the species of birds that exist on the planet." Although many of us may have been taught to think of "germs" and "bacteria" as threats, most of the species we live with are harmless or even beneficial to us, and DeSalle and Perkins argue that "our definition of what a pathogen is clearly needs to change." They cover the origins and definitions of life; the relationships of the "three great domains of life--Archaea, Eukaryota and Bacteria"; our attempts to detect and identify them, including genetic sequencing; how immune systems work in higher and lower animals; and how microbes travel, interact and affect us, including studies of microbes and roller derby teams, subways, obesity and mental health. They emphasize that this is not just a subject for scientists: "Our very survival may well depend on understanding, and respecting, the ecology and evolutionary context of the microbiomes in and on us." --Sara Catterall