I Contain Multitudes: The Microbes Within Us and a Grander View of Life

by Ed Yong

As the baby picks up new species from its parents and environment, its gut microbiome becomes gradually more diverse.

Many conditions, including obesity, asthma, colon cancer, diabetes, and autism, are accompanied by changes in the microbiome, suggesting that these microbes are at the very least a sign of illness, and at most a cause of it.

let us note that these questions can be answered only by collecting small pieces of data, just as Darwin and Wallace did on their seminal voyages.

“Nothing is more crucial to the survival and independence of organisms – be they elephants or protozoa – than the maintenance of a constant internal environment.”

can sway the brain too – the organ that, more than any other, makes us who we are.

The meaning of these differences is open to debate, but they do at least show that bacteria can affect human brain activity.45