size_source_pool(speciesData = 21:30, sourcePool = runif(n = 2 * length(speciesData), min = 10, max = 50), speciesProbs = rep(1, length(sourcePool)))
Function to randomize body sizes by drawing species from a user-defined source pool. Species are drawn without replacement, and there is a specified probability vector for the source pool species
Although delineating a source pool of species and estimating their relative colonization probabilities is difficult, this is the most realistic approach to constructing a null distribution.
Strong, D.R. Jr., L.A. Szyska, and D. Simberloff. 1979. Tests of community-wide character displacement against null hypotheses. Evolution 33: 897-913. Schluter, D. and P.R. Grant. 1984. Determinants of morphological patterns in communities of Darwin's finches. American Naturalist 123: 175-196.
obsOverlap <- size_source_pool(dataRodents$Sonoran)