Skip to contents

Compute pairwise "niche overlap" in geographic space for Maxent predictions. The value ranges from 0 (no overlap) to 1 (identical predictions). The function uses the nicheOverlap function of the dismo package (Hijmans et al. 2011).

Usage

calc.niche.overlap(predictors, overlapStat, quiet = FALSE)

Arguments

predictors

SpatRaster: at least 2 Maxent raster predictions

overlapStat

character: either "D" or "I", the statistic calculated by the nicheOverlap function of the dismo package (default: "D"), which we updated for terra as no correlate currently exists in the new predicts package

quiet

boolean: if TRUE, silence all function messages (but not errors)

Value

A matrix with the lower triangle giving values of pairwise "niche overlap" in geographic space. Row and column names correspond to the results table output by ENMevaluate().

Details

"D" refers to Schoeners D (Schoener 1968), while "I" refers to the I similarity statistic from Warren et al. (2008).

References

Hijmans, R. J., Phillips, S., Leathwick, J. & Elith, J. (2011) dismo package for R. Available online at: https://cran.r-project.org/package=dismo.

Schoener, T. W. (1968) The Anolis lizards of Bimini: resource partitioning in a complex fauna. Ecology, 49: 704-726. doi:10.2307/1935534

Warren, D. L., Glor, R. E., Turelli, M. & Funk, D. (2008) Environmental niche equivalency versus conservatism: quantitative approaches to niche evolution. Evolution, 62: 2868-2883. doi:10.1111/j.1558-5646.2008.00482.x

See also

`nicheOverlap` in the dismo package

Author

Based on dismo::nicheOverlap, which is based on SDMTools::Istat, updated for terra package Robert Muscarella <bob.muscarella@gmail.com>