Quantifying niche similarity among new world seed plants--Species Distribution Models (SDMs) & associated metadata
Authors/Creators
- 1. University of Michigan-Ann Arbor
- 2. University of New Mexico
- 3. University of Kansas
- 4. Mississippi State University
- 5. University of Florida
Description
Niche shift and conservatism are often framed as mutually exclusive. However, both processes could contribute to biodiversity patterns. We tested this expectation by quantifying the degree of climatic niche similarity among New World seed plants.
To incorporate the biological reality that species experience varied abiotic conditions across their range, we assembled distribution models and used these to characterize temperature, precipitation, and elevation niches for species as continuously-valued distributions. We then quantified niche similarity (distributional overlap) and identified statistically significant differences compared to a randomized null.
The degree of niche similarity differed among climate variables, plant lineages, and at different phylogenetic scales. For example, ~17% of all seed plants were significantly different in elevational niche from their closest relative(s), whereas for precipitation, this value was only ~4%. Average niche similarity decreased with increasing phylogenetic distance, consistent with niche conservatism; however, variance in niche similarity among close relatives was large, such that there always existed niche differences equaling those among distantly related species.
Our results suggest researchers should incorporate both niche shift and conservatism as important, scale-dependent factors shaping biodiversity patterns as these processes are not mutually exclusive, nor do they contribute equally to patterns among different plant lineages or niche variables.
Notes
This dryad deposit contains a zipped folder which in turn has subfolders for each genus in our dataset. The genus folders contain the Species Distribution Models (SDMs) as raster files in a .TIFF format. SDMs should be accessible with any software suitable for handling such rasters (R, Python, QGIS, etc.).
Please note that this folder contains SDMs for >72, 000 species and as such is quite large (~800 GB when unzipped). We highly recommend using a higher-performance computer with suitable storage capabilities (or external storage device); opening on a personal laptop may not be feasible for many users.
SDMs were used to characterize the climatic niches of American seed plants with respect to temperature, precipitation, and elevation as described in the associated publication. Custom scripts used to parse each SDM into each of these climate variables is available in the Online Supplement (Scripts folder), as well as within this dryad deposit. Climate data used to parse SDMs was obtained from WorldClim, and users could easily parse SDMs into other climate layers or raster/ shape files for their own purposes.
Funding provided by: National Science Foundation
Crossref Funder Registry ID: http://dx.doi.org/10.13039/100000001
Award Number: 1930005
Funding provided by: National Science Foundation
Crossref Funder Registry ID: http://dx.doi.org/10.13039/100000001
Award Number: 1930007
Funding provided by: National Science Foundation
Crossref Funder Registry ID: http://dx.doi.org/10.13039/100000001
Award Number: 1930030
Funding provided by: National Science Foundation
Crossref Funder Registry ID: http://dx.doi.org/10.13039/100000001
Award Number: 1338694