from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun An association between two organisms of different species in which each member benefits.

from The Century Dictionary.

  • noun A symbiosis in which two organisms living together mutually and permanently help and support one another.
  • noun Lichens are examples among plants.

from the GNU version of the Collaborative International Dictionary of English.

  • noun (Ethics) The doctrine of mutual dependence as the condition of individual and social welfare.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun ecology any interaction between two species that benefits both; typically involves the exchange of substances or services

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun the relation between two different species of organisms that are interdependent; each gains benefits from the other


from Wiktionary, Creative Commons Attribution/Share-Alike License

mutual +‎ -ism


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  • The meaning of the word mutualism has, in recently years, been extended from its original meaning in classical ecology.

    Chapter 6 1995

  • If you look at a great eco-system like a choral community you find a very complex community of individuals which co-operate together and work together in mutualism, or what we call symbiosis.

    The Runaway Brain 1984

  • One such route is via the idea of mutualism, which gave rise to the great friendly society, mutual assurance society, credit union and co-operative movements.

    Archive 2009-08-01 John M 2009

  • A mutualism is a symbiotic interaction between two species in which both species benefit, and is therefore a + + (double positive) interactions.

    Community ecology 2008

  • The term 'symbiosis' builds on the notion of mutualism in biological communities where at least two otherwise unrelated species exchange materials, energy, or information in a mutually beneficial manner.

    Industrial symbiosis 2008

  • The saga of human-feline mutualism, which is often non-obligatory on both sides of the relationship, thus offers lessons for game theory.

    Archive 2006-07-01 2006

  • And what worries me is that people will get the wrong idea about both co-operative businesses and about "Mutualism" and if these attempts to use co-ops in public policy do not work out as well as they are now being touted will be disillusioned with the idea of mutualism, and Mutualism, itself.

    #039;s Place - Comments 2010

  • But the way most of us think of symbiotic relationships is the kind called "mutualism" where both parties benefit from the relationship.

    Vendors, Publishers & Librarians - a Symbiotic Relationship 2006

  • The term "mutualism" as applied to these cases means, of course, that the aphids, coccids, and membracids are of service to the ants and in turn profit by the companionship of these more active and aggressive insects.

    Introduction to the Science of Sociology Robert Ezra Park 1926

  • Among other things, he advocated what he called "mutualism," an economic practice that disincentivized profit - which, according to him, was a destabilizing force - and argued far ahead of his time for banks with free credit and unions to protect labor. Top Stories 2011


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  • "The interaction between the ants and their fungus crop, and the ants and the bacteria is known as a mutualistic relationship. In general a mutualism is established when both members of the interaction benefit from the relationship. In the ant–fungus mutualism, the ants get food from the fungus. This mutualism is so tight that if the fungus is lost, the entire colony may die. In return, the fungus receives a continuous supply of growing material, protection from the environment, and protection from disease-causing pests."

    - 'Sustainable Agriculture - What Ants Knew 50 Million Years Before We Did',, 16 Nov 2008.

    November 17, 2008

  • Big surprise that zombie ants originated from a comment by bilby. I'm guessing there is a specific parasite out there that is manipulating bilby's brain into performing erratic behaviors so he'll get the attention of a bilby-eating predator (the next intended host).

    March 6, 2017

  • Yeah, as if vending machines were known for ripping up the MENSA test.

    March 7, 2017

  • Just gimme a muesli bar already you money-chewing, overstuffed, zincalume clink-clunk dole-da-junk denizen of shitty workplaces.

    March 7, 2017

  • A parasite is no doubt altering bilby's dopaminergic neurotransmissions resulting in neuropsychiatric symptoms, including a change in predator vigilance. it's also entirely possible that parasites have affected bilby's sexual arousal pathways when he's exposed to muesli bars soaked in dingo urine.

    March 7, 2017

  • Go back to doing what you do best, you know, stealing children's pocket money in exchange for giving them diabetes.

    March 8, 2017

  • Not a question to ask on the mutualism page.

    March 9, 2017

  • Is it bad that my first thought upon reading this thread was to wonder whether dingo urine would render those muesli bars non-vegan?

    March 14, 2017