(NYT Magazine) – The human microbiome is essential to our health, but scientists still know very little about it. Two researchers set out to map this largely uncharted terrain.

Scientists refer to this vast, unexplored terrain as biology’s dark matter. Our bodies are home to more bacteria — on our skin, up our noses, in our guts and mouths and around our genitals — than there are stars in the Milky Way. These microbes have evolved not only with us but inside us, and scientists who study them closely say that hardly a biological process or system exists in which they do not play a role. They helped create our digestive systems and our immune systems. They influence the size and shape of our bodies. At least some research suggests that they also affect our brains, moods, personalities and behaviors. And yet, most of them have still not been identified, let alone studied. (Read More)