STANFORD, Calif. — Researchers at the Stanford University School of Medicine are as interested in a baby’s poop as doting parents are, and for good reason.When a baby is born, so too is a new microbial ecosystem in the baby’s gut. The Stanford team has made the most extensive survey yet of how the microbes establish flourishing communities in what began as a sterile environment. Their findings will be published in the July issue of Public Library of Science-Biology.