"The microorganisms that decompose the organic matter in the surface soil [of tropical forests] are aided by bacteria and single-celled animals in the alimentary canals of termites, cockroaches, and beetles.  The ubiquitous termites depend on protozoa, which permanently inhabit their gut, for cellulose digestion, and similarly the ants that cultivate fungus gardens use the fungi to digest the cellulose of their plant harvests, for they themselves are unable to do it alone."—Thank you, Michael Emsley (writer) and Kjell B. Sandved (photographer) for Rain Forests and Cloud Forests, Harry N. Abrams, Inc., 1979, p.115