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An interaction between two species that benefits both. Individualsthat interact with mutualists experience higher sucess than those that do not.Hence, behaving mutualistically is advantageous to the individual, and it doesnot require any concern for the well-being of the partner. At one time,mutualisms were thought to be rare curiosities primarily of interest to naturalhistorians. However, it is now believed that every species is involved in oneor more mutualisms. Mutualisms are thought to lie at the root of phenomena asdiverse as the origin of the eukaryotic cell, the diversification of floweringplants, and the pattern of elevated species diversity in tropical forests.

Mutualisms generally involve an exchange of substances or services thatorganisms would find difficult or impossible to obtain for themselves. Forinstance, Rhizobium bacteria found in nodules on the roots of manylegume (bean) species fix atmospheric nitrogen into a form (NH3)that can be taken up by plants. The plant provides the bacteria with carbon inthe form of dicarboxylic acids. The carbon is utilized by the bacteria asenergy for nitrogen fixation. Consequently, leguminous plants often thrive innitrogen-poor environments where other plants cannot persist. Anotherwell-known example is lichens, in which fungi take up carbon fixed duringphotosynthesis of their algae associates.

A second benefit offered within some mutualisms is transportation. Prominentamong these mutualisms is biotic pollination, in which certain animals visitflowers to obtain resources and return a benefit by transporting pollen betweenthe flowers they visit. A final benefit is protection from one's enemies.For example, ants attack the predators and parasites of certain aphids inexchange for access to the aphids' carbohydrate-rich excretions(honeydew).

Another consideration about mutualisms is whether they are symbiotic. Twospecies found in intimate physical association for most or all of theirlifetimes are considered to be in symbiosis. Not all symbioses are mutualistic;symbioses may benefit both, one, or neither of the partners.

Mutualisms can also be characterized as obligate or facultative (dependingon whether or not the partners can survive without each other), and asspecialized or generalized (depending on how many species can confer thebenefit in question).

Two features are common to most mutualisms. First, mutualisms are highlyvariable in time and space. Second, mutualisms are susceptible to cheating.Cheaters can be individuals of the mutualist species that profit from theirpartners' actions without offering anything in return, or else otherspecies that invade the mutualism for their own gain.

Mutualism has considerable practical significance. Certain mutualisms playcentral roles in humans' ability to feed the growing population. It hasbeen estimated that half the food consumed is the product of bioticpollination. See Ecology, Plant pathology


Mutual interactions between two species that are beneficial to both species.
References in periodicals archive ?
Proudhon concluded that despite their differing contexts, both the Italian question and the Polish question ought to have been resolved by the principle of mutualist federation.
Second, this conceptual model does not suggest instability as do population-level models such as May's (1973), in which population sizes of mutualists increase without bound (an "orgy of mutual benefaction").
Nevertheless, mutualist clinics provided a collective attitude to medical work which would become critical after the 1959 revolution.
35) This is also, incidentally, the reason the mutualist "occupancy" position on land ownership is unlibertarian.
However, broadly speaking, mutualist genomes preferentially retain fundamental cellular processes (e.
For Kant (at least in his mutualist mode), to approach the question of membership from a presumption that "delineation must come first" puts the political cart before the horse: the regulative ideal of the delineative approach not only misunderstands the analytic priority of settling entry before deliberation, its particular misunderstanding is antithetical to the very individual and social process that makes possible a public space.
Alongside profit-oriented private enterprise and the various types of public enterprise, there must be room for commercial entities based on mutualist principles and pursuing social ends to take root and grow.
As a Mutualist, Tucker rigorously embraced free markets and voluntary exchange void of all government privilege and regulation.
His written work, all of which is freely availiable online, includes "Studies in Mutualist Political Economy, Organization Theory: An Individualist Anarchist Perspective," and "The Homebrew Industrial Revolution: A Low-Overhead Manifesto.
The activities of the Hartlepool Good Intent Lodge provide an example of how a club's private administration of capital, public desire for respectability, and mutualist approach to charity intersected.
For instance, debate about the collective liberal concept of "community" was particularly important since it could be used to "forge a strong mutualist bond among their members and as a strategem to eliminate opposition to liberal ideas.
In the 19th century, Raiffeisen initiated the savings and loan cooperatives in Germany that have evolved into the mutualist banks of Europe and the New World.