The Enteric Microbiota (Colloquium Series on Integrated Systems Physiology)

Bacteria have lived in and on animal hosts since multicellular life evolved about 1 billion years ago. Hosts provide habitat and nutrition to the microbial communities and derive many benefits from their guests that contribute with metabolic (recovery of energy and nutrients), defensive (barrier effect against invaders) and trophic (immune regulation, neuro-endocrine development) functions.