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On the theory of niche overlap
Theoretical Population Biology, 1974Abstract The factors which are likely to limit niche overlap are studied for a class of idealized biological communities in which several species compete on a onedimensional continuum of resources, e.g., food size. Although the shape of the resource spectrum restricts the composition of possible equilibrium communities, and although this restriction ...
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On the limit to niche overlap for nonuniform niches
Theoretical Population Biology, 1976Abstract May and MacArthur (1972) have demonstrated that where several species are in competition for a single resource the requirement of long term population stability sets an upper limit to the allowable similarity of competing species. Their model considers a community of N species competing on a one dimensional resource continuum e.g., food ...
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Multivariate measures of similarity and niche overlap
Theoretical Population Biology, 1989Niche overlap measures are used to assess the similarity in resource use by two species. Recently researchers have used niche overlap measures as summary measures and for making inferences, typically about competition for resources. The problem of estimating niche overlap when the niches are multivariate normal distributions with equal covariance ...
Lu, Ruey-Pyng +2 more
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Oikos, 1982
The niche overlap hypothesis states that "maximal tolerable overlap should vary inversely with the intensity of competition." Rigorous testing of this hypothesis has been complicated by problems of measurement and by the difficulty of formulating operational definitions of "maximal tolerable overlap" and "intensity of competition." We test this ...
John H. Porter, Raymond D. Dueser
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The niche overlap hypothesis states that "maximal tolerable overlap should vary inversely with the intensity of competition." Rigorous testing of this hypothesis has been complicated by problems of measurement and by the difficulty of formulating operational definitions of "maximal tolerable overlap" and "intensity of competition." We test this ...
John H. Porter, Raymond D. Dueser
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Bias in Estimating Niche Overlap
Ecology, 1982Bias refers to the accuracy of a particular estimator. We evaluate bias, using analytic and simulation technics, for six measures of overlap: the likelihood ratio measure, the chi—square measure, the measure based on the Freeman—Tukey statistic, Morisita's adjusted index, Morista's original index, and Horn's information index.
Eric P. Smith, Thomas M. Zaret
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Niche Overlap and Competition in Woodrats
Journal of Mammalogy, 1971The ranges of Neotoma lepida and Neotoma fuscipes overlap in the Mohave Desert of southeastern California. Food resources of these woodrats were analyzed to determine degree of overlap and other possible competitive interactions. In most aspects of habitat, the two species are distinctly separated, but analyses of food caches and stomach contents ...
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A note on structural holes theory and niche overlap
Social Networks, 2003Diffuse competition due to niche overlap between actors without (direct) ties with each other, constrains their structural autonomy. This is not dealt with in Burt’s mathematical model of his well-known structural holes theory. We fix his model by introducing a network measure of niche overlap.
Bruggeman, J.P. +3 more
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NICHE — Programs for Niche Breadth, Overlap and Hypervolumes
1991The concept of niche involves two complementary aspects, one related to the hypervolume occupied by a species or a community in the ecological space (e.g. Hutchinson 1957, 1978; Feoli, Ganis and Woldu 1988) and the other related to the pattern of resources exploitation and competition (e.g.
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Niche overlap and environmental variability
Mathematical Biosciences, 1976Abstract This article investigates whether several forms of environmental variability will limit niche overlap in a group of competing organisms. A simulation method was used to answer this question for the Lotka-Volterra model of competition. The basic result is that the maximum tolerable variability is significantly less for systems with high ...
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Niche Width and Niche Overlap: A Method for Measuring Them
Ecology, 1972Suppose r different animal species are found in some or all of c different habitats. Observations on the numbers of occurrences of the animals in the habitats can be tabulated in an r ° c table. The overall "diversity" of the table, HT say, is defined as Brillouin's information measure with the r ° c table's cell frequencies of the different "symbols."
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