The Microbiota and the Environment

In 1875, Pierre-Joseph von Benadine presented over 250 examples of relationships between a microorganism and a larger multicellular organism. What Van Benadine was describing with his messmate was a commensal relationship. Ecologically, commensal relationships occur when one organism benefits without helping or harming the other. The microbiome refers to all organisms inhabiting the body, from bacteria to viruses to parasites.