Global priorities for conservation across multiple dimensions of mammalian diversity

Abstract

Conservation priorities that are based on species distribution, endemism, and vulnerability may underrepresent biologically unique species as well as their functional roles and evolutionary histories. To ensure that priorities are biologically comprehensive, multiple dimensions of diversity must be considered. Further, understanding how the different dimensions relate to one another spatially is important for conservation prioritization, but the relationship remains poorly understood. Here, we use spatial conservation planning to (i) identify and compare priority regions for global mammal conservation across three key dimensions of biodiversity-taxonomic, phylogenetic, and traits-and (ii) determine the overlap of these regions with the locations of threatened species and existing protected areas. We show that priority areas for mammal conservation exhibit low overlap across the three dimensions, highlighting the need for an integrative approach for biodiversity conservation. Additionally, currently protected areas poorly represent the three dimensions of mammalian biodiversity. We identify areas of high conservation priority among and across the dimensions that should receive special attention for expanding the global protected area network. These high-priority areas, combined with areas of high priority for other taxonomic groups and with social, economic, and political considerations, provide a biological foundation for future conservation planning efforts.

Keywords: complementarity; phylogenetic dimension; spatial conservation prioritization; taxonomic dimension; trait dimension.

Fig. 1.

The top 17% of cells selected according to zonation prioritization based on the taxonomic dimension, phylogenetic dimension, trait dimension and on the overlap across the three dimensions. In the overlap map, cells in which all three dimensions overlap are shown in dark green, those in which two dimensions overlap are shown in light green, and those selected only by one dimension are shown in orange.

Fig. 2.

Venn diagram showing the proportion of the land surface where we can observe the overlap between the top 17% priority areas across the taxonomic, phylogenetic, and trait dimensions of biodiversity, referent to the overlap map presented in Fig. 1. For example, only 1.8% of the land was selected as an area of priority for both the taxonomic and trait dimensions. The color scheme is that used in the overlap map in Fig. 1.

Fig. S1.

Priority map for conservation of terrestrial mammals according to Zonation analysis, using CAZ. (Top) The map based on the taxonomic dimension. (Middle) The map based on the phylogenetic dimension. (Bottom) The map based on the traits dimension.

Fig. S2.

Correlation plots of the conservation value of each cell resulting from Zonation analysis based on species occurrences (Species), phylogenetic groups (Phylogeny), and trait values (Traits). The Kendall correlation (τ) coefficient is indicated above the plots.

Fig. S3.

Plots of the correlation between mammal species richness per cell and the conservation rank of each cell resulting from Zonation analysis based on species occurrences (Species), phylogenetic groups (Phylogeny), and trait values (Traits). The Kendall correlation (τ) coefficient is indicated above the plots.

Fig. S4.

Plots of the correlation between the number of threatened mammal species per cell and the conservation rank of each cell resulting from Zonation analysis based on species occurrences (Species), phylogenetic groups (Phylogeny), and trait values (Traits). The Kendall correlation (τ) coefficient is indicated above the plots.

Fig. S5.

Conservation values inside currently protected areas (PAs) from the conservation solutions based on the three dimensions of biodiversity (species, phylogeny, and traits). The dotted line indicates the 17% target for conservation, showing that species, phylogeny, and traits that are rare are poorly represented within protected areas.

Fig. 3.

The overlap across areas important for the taxonomic, phylogenetic, and trait dimensions (brown), the current network of protected areas (green), and areas of overlap that are already protected (orange).