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8.3: Summary of interactions

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    In summary, based on the effects of each population on the other, two species can interact mainly in three different ways, as shown in Figure \(\PageIndex{1}\). Competition is a ‘−−’ combination, mutualism is ‘++’, and predation is ‘+−’, in either order.

    Summary of interactions.JPG
    Figure \(\PageIndex{1}\). Summary of species interactions based on signs of their interaction parameters.

    Sandwiched between the boxes above are special cases where one of the interaction terms is zero, or very close to zero. These are called “commensalism,” when one parameter is positive and the other is zero, or “amensalism,” when one parameter is negative and the other is zero. We won’t focus further on these special cases.

    This page titled 8.3: Summary of interactions is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Clarence Lehman, Shelby Loberg, & Adam Clark (University of Minnesota Libraries Publishing) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.