Area, isolation, and climate explain the diversity of mammals on island worldwide

Identifying the determinants of insular biodiversity at large scales remains a question in biogeography. We conducted a global test of island biogeography theory by evaluating the importance of island physical, environmental, and historical characteristics on mammal species richness and endemism. We quantified the effects of island characteristics while accommodating variation among biogeographic realms by fitting generalized linear and mixed models. Analyzes were also performed separately for bats and non-volant mammals. Diversity patterns were most consistently influenced by the physical characteristics of the islands. Area positively affected mammal diversity, in particular the number of non-volant endemics. Island isolation, both current and past, was associated with lower richness but greater endemism. Flight capacity modified the relative importance of past versus current isolation, with bats responding more strongly to current and non-volant mammals to past isolation. Environment..., We derived a global database of mammalian insular biodiversity by using the Global Administrative areas version 3.6 (GADM, 2018) to subset spatial polygons of all land masses smaller than Greenland (2,166,000 km²) that are surrounded by salty water and overlapping it with the mammalian range maps from IUCN (IUCN, 2017). We carefully inspected and manually corrected any other alignment inconsistencies using QGIS 3.6 (Open Source Geospatial Foundation Project, 2019). We opted for a highly conservative approach of excluding any island with the slightest doubt about species attribution and ignoring islands where no mammal species occurs according to the IUCN data (i.e., our dataset only includes islands with at least one species). For example, regions with clusters of nearby islands – e.g., Patagonia and Scandinavia. We removed introduced species from the database by excluding (1) species polygons recorded as introduced by IUCN and (2) species listed as invasive for each particular island i..., We excluded from the dataset those islands where no mammal species occur so that the dataset only includes islands with at least one species. Appendix 1 contains the presence and absence matrix of mammal species per island. The name of the rows is paired with the ID column in the spreadsheet in Appendix 2, which contains the island's physical, environmental, and biotic variables. The file \"mammal_insularity_from_IUCN.csv\" contains a list of all the mammal species in the presence and absence matrix and a categorization indicating whether the species is only \"continental\", \"continental_and_insular\" or only \"insular\"., # Mammal diversity on islands worldwide

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Data from: Barreto Elisa, Rangel Thiago F., Pellissier Loc and Graham Catherine H. 2021Area, isolation and climate explain the diversity of mammals on islands worldwideProc. R. Soc. B.2882021187920211879 [http://doi.org/10.1098/rspb.2021.1879](http://doi.org/10.1098/rspb.2021.1879)

This data contains a presence and absence matrix of mammal species per island and a compilation of mammalian species richness, endemism and a series of physical and environmental characteristics of each island. A total of 5,592 islands (out of the ~17,000 islands larger than 1km worldwide; Weigelt et al., 2013) are included in the data.

## Versioning

June 2024 update: Appendix 1 with the presence-absence matrix was updated to remove 15 duplicated entries. The file \"mammal_insularity_from_IUCN.csv\" was added.

## Description of the Data

We derived aglobal database of mammal species on over 5,500 islands worldwide by overlapping island shapefiles from theGlobal...