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Ecogeographical variables on the 4 global TDWG levels

The Biodiversity Information Standards (formerly Taxonomic Database Working Group, TDWG) have defined a world geographical scheme for recording species distributions. This consists of geographical units defined at four nested levels of spatial resolution: TDWG level 1 is at the coarser scale and includes 9 continental areas (Africa, Antarctica, Asia-temperate, Asia-tropical, Australasia, Europe, Pacific, Northern America, and Southern America); level 2 includes 52 sub-continental regions; level 3 includes 369 units, mostly corresponding to countries or large intra-national regions; and level 4 has 609 units, including states for the largest countries. Shapefiles representing these geographical divisions are available online.

We compiled a set of environmental, human, and spatial variables useful to perform macroecological analyses of species' distribution and diversity patterns, and obtained their values in each spatial unit on the 4 TDWG levels using Quantum GIS and GRASS software. This electronic database is provided as supplementary material to Fontaneto et al. (2012), who describe the sources of the variables and how they were processed.

Please cite the following paper when using these data:

Fontaneto D., Barbosa A.M., Segers H. & Pautasso M. (2012) The ‘rotiferologist’ effect and other global correlates of species richness in monogonont rotifers. Ecography 35: 174-182