Human: What is a symbiotic relationship, and what are some examples of symbiotic relationships? Assistant: 
A symbiotic relationship is one in which two organisms live together in close association, typically to the mutual benefit of both. Examples include lichens, corals, and mycorrhizal fungi that form mutually beneficial associations with plants. Other examples include the gut bacteria of mammals, which help digest food, and the nitrogen-fixing bacteria of legumes, which convert atmospheric nitrogen into a form usable by plants.