World Library  
Flag as Inappropriate
Email this Article

Trophic mutualism

Article Id: WHEBN0022648747
Reproduction Date:

Title: Trophic mutualism  
Author: World Heritage Encyclopedia
Language: English
Subject: Mutualism (biology), Landscape ecology, Trophic, Recruitment (biology), Copiotroph
Collection: Behavioral Ecology, Ecology Terminology, Mutualism (Biology)
Publisher: World Heritage Encyclopedia

Trophic mutualism

Trophic mutualism is a key type of ecological mutualism. Specifically, "trophic mutualism" refers to the transfer of energy and nutrients between two species. This is also sometimes known as resource-to-resource mutualism. Trophic mutualism often occurs between an autotroph and a heterotroph.[1] Although there are many examples of trophic mutualisms, the heterotroph is generally a fungus or bacteria. This mutualism can be both obligate and opportunistic.


  • Examples 1
  • History of Trophic Mutualism Research 2
  • See also 3
  • References 4


  • Rhizobia- Rhizobia are bacteria that conduct Nitrogen fixation for legume plants. Specifically, these bacteria can be from generas Allorhizobium, Azorhizobium, Bradyrhizobium, Mesorhizobium, Rhizobium, or Sinorhizobium.[2] In this mutualistic relationship, the bacteria grow on or within the root hair and penetrate into the plant tissues[3] Although the exact means of interaction between the Rhizobia and plant varies with genus and species, all forms of this interaction are made up of the infection of bacteria, bacteria colonization, control of O2, and exchange of Carbon and Nitrogen.[4] The role that rhizobias play in fixing nitrogen for legumes is the basis for why legumes can be used in crop rotation.[5]
  • Mycorrhizae- Mycorrhizae are similar to rhizobia in that they interact with plants at their roots. Whereas Rhizobia are bacteria that fix nitrogen, mycorrhizas are fungi that bring nutrients to the plants in return for carbon. Mycorrhizas are also capable of improving water uptake and communicating to their hosts to resist to pathogens.[6] Three main types of mycorrhizae exist:
  1. Arbuscula: found in non-woody and tropical plants
  2. Ectomycorrhiza: found in boreal and temperate forests
  3. Ericoid: found in species of the heathland.[7]
  • Digestive symbyotes – Digestive symbyotes are an example of an important trophic mutualism that does not occur between an autotroph and heterotroph. Bacteria known as “extracellular symbionts”[8] live within the gastrointestinal tracts of vertebrates, where they aid in the digestion of food. The bacteria benefits by extracting substrates from the eaten food, while the animal’s assimilation is increased by being able to digest certain foods that it’s natural system cannot. (book) In addition, these bacteria create short-chain fatty acids (SCFA), providing the vertebrate with energy totaling up to anywhere from 29%-79% of the vertebrate’s maintenance energy depending on the species.[9]

History of Trophic Mutualism Research

Ecologists first began to understand trophic mutualisms in the mid-20th century with the investigation of nutrient abundance and distribution. One of the first trophic mutualisms was discovered in 1958 by Professor Leonard Muscatine of UCLA, the relationship between endozoic algae and coral.[10] In this relationship, the algae provides the coral with a Carbon source to develop its CaCO3 skeleton and the coral secretes a protecting nutrient rich mucus which benefits the algae. Perhaps one of the most famous discoveries made by Muscatine in the field of trophic mutualism came about 10 years later in another aquatic based system-the relationship between algae and water hydra.[11] This work was significant in establishing the presence of mutualistic relationships in both aquatic and terrestrial environments.

Perhaps the most widely acclaimed example of a trophic mutualism was the discovery of the leafcutter ant that engage in trophic mutualism with a fungus.[12] These ants cultivate a certain type of fungus by providing it with leaves and other nutrients. In turn the ants will feed on a special nutrient that is only created by the fungus they nurture. This trophic mutualism was studied in detail in the 1970s and since.

See also


  1. ^ Odum, Eugene. Fundamentals of Ecology. 3rd ed. Philadelphia: W.B. Saunders Company, 1971.
  2. ^ Vessey, K.J., K. Pawlowski, and B. Bergman, Root-based N2-fixing symbioses: Legumes, actinorhizal plants, Parasponiasp. and cycads. Plant and Soil 2005. 266(1-2): p. 205-230.
  3. ^ Townsend, C.R., M. Begon, and J.L. Harper, Essentials Of Ecology Third Edition 2008, Malden, MA: Backwell Publishing
  4. ^ Vessey, K.J., K. Pawlowski, and B. Bergman, Root-based N2-fixing symbioses: Legumes, actinorhizal plants, Parasponiasp. and cycads. Plant and Soil 2005. 266(1-2): p. 205-230.
  5. ^ Saito, K., B. Linquist, and B. Keobualapha, Stylosanthes guianensis as a short-term fallow crop for improving upland rice productivity in northern Laos. Field Crops Research 2006. 96(2/3): p. 438-447.
  6. ^ Douglas H. Boucher, Sam James and Kathleen H. Keeler Annual Review of Ecology and Systematics, Vol. 13, (1982), pp. 315-347
  7. ^ Townsend, C.R., M. Begon, and J.L. Harper, Essentials Of Ecology Third Edition 2008, Malden, MA: Backwell Publishing
  8. ^ Townsend, C.R., M. Begon, and J.L. Harper, Essentials Of Ecology Third Edition 2008, Malden, MA: Backwell Publishing
  9. ^ Stevens, C.E. and I.D. Hume, Contributions of Microbes in Vertebrate Gastrointestinal Tract to Production and Conservation of Nutrients. Physiological Reviews, 1998. 72(2): p. 383-427.
  10. ^ Hoegh-Guldberg, O., et al., Len Muscatine (1932–2007) and his contributions to the understanding of algal-invertebrate endosymbiosis. Coral Reefs, 2007. 26(4): p. 731-739.
  11. ^ Muscatine, Leonard, and Howard Lenhoff. "Symbiosis: On the Role of Algae Symbiotic with Hydra." Science 142 (19681): 956-58.e
  12. ^ Weber, Neal A. 1972. Gardening Ants the Attines. The American Philosophical Society. Philadelphia
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.