Results 261 to 270 of about 52,051 (301)

NICHE — Programs for Niche Breadth, Overlap and Hypervolumes

1991
The 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, 1976
Abstract 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, 1972
Suppose 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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Overlap and partitioning of the ecological and isotopic niches

Oikos, 2010
Recently, it was proposed that stable isotope patterns can be used to quantify the width of the ecological niche of animals. However, the potential effects of habitat use on isotopic patterns of consumers have not been fully explored and consequently isotopic patterns may yield deceptive estimates of niche width.
Elizabeth A. Flaherty, Merav Ben‐David
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Trees have overlapping potential niches that extend beyond their realized niches

Science
Tree species appear to prefer distinct climatic conditions, but the true nature of these preferences is obscured by species interactions and dispersal, which limit species’ ranges. We quantified realized and potential thermal niches of 188 North American tree species to conduct a continental-scale test of the architecture of niches. We found strong and
Daniel C. Laughlin, Brian J. McGill
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Niche Overlaps and the Evolution of Competitive Interactions

1989
Several theoretical studies have suggested that the nature of interactions between species effect the structure of communities. Most of these studies were based on the analysis of an interaction matrix A, and its stability properties. The elements of this matrix describe the interactions between species: diagonal elements α ii describe the effect of ...
H. Reşit Akçakaya, L. R. Ginzburg
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Individual foraging specialization: niche width versus niche overlap

Oikos, 2007
(Uploaded by Plazi for the Bat Literature Project) No abstract provided.
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Likelihood Measures of Niche Breadth and Overlap

Ecology, 1979
Currently used niche measures of overlap and breadth are shown to be inappropriate for analyzing field data. Previously proposed measures assume resources are equally available, but this assumption is unwarranted in field studies. Comparisons of different measures of either breadth or overlap are also not valid. A measure of niche breadth is derived by
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Multivariate measures of niche overlap using discriminant analysis

Theoretical Population Biology, 1977
Abstract Two measures of multivariate niche overlap defined on p resource variables are presented. By measuring the niche overlap on the discriminant variable the multivariate problem is reduced to a univariate problem while preserving the relevant multivariate information. The niche overlap is then calculated by two different techniques.
E J, Harner, R C, Whitmore
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The Measurement of Niche Overlap and Some Relatives

Ecology, 1978
Existing overlap indices are examined and are judged to be inadequate on the grounds (1) that they lack simple and appropriate biological interpretations, and (2) that they ignore possible variation among resource states in abundance or availability (a_i). Two indices interpretable in terms of encounters are proposed.
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