Aim
Beta diversity analyses clarify mechanisms structuring ecological communities, but their multidimensional facets remain poorly explored in arthropods. Here, we quantified taxonomic, phylogenetic, and functional beta diversity in scorpions, partitioned these facets into species replacement and richness differences, and evaluated the relative importance of spatial structure and environmental conditions in driving community assembly.
Location
Northeastern Brazil, South America.
Taxon
Scorpions (Arachnida: Scorpiones).
Methods
Taxonomic beta diversity was estimated using species presence across 70 sites in northeastern Brazil. Phylogenetic turnover was calculated from a multi-locus molecular tree, and functional beta diversity was derived from morphometric and ecological traits. All beta diversity facets were decomposed into replacement and richness-difference components. We applied Moran's eigenvector maps to represent spatial structure and used variation partitioning to test the independent and shared contributions of environmental factors and space.
Results
Beta diversity was high across all facets and dominated by species replacement, indicating that assemblages differ mainly through species substitution rather than species gain or loss. Spatial analysis revealed that the three beta diversity facets are organized largely by broad-scale spatial autocorrelation matching a longitudinal climatic gradient. Variation partitioning showed that environmental characteristics explained more variation than pure spatial predictors for all beta diversity facets. Phylogenetic beta diversity, especially its replacement component, exhibited the strongest environmental signal, supporting the idea that closely related lineages retain similar climatic tolerances. Functional beta diversity showed weaker, although still substantial, environmental structuring, suggesting partial decoupling between function and lineage identity.
Main Conclusions
Our findings support species sorting along a climatic gradient as the primary determinant of scorpion beta diversity, with dispersal limitation playing a secondary role. Climatically distinct environments shelter phylogenetically unique assemblages, reinforcing the importance of conserving sites across the full climatic spectrum. These results emphasize that analyses restricted to taxonomic data may underestimate the depth of ecological and evolutionary turnover occurring across environmental gradients.
Araújo Foerster, S. Í., & Lira, A. (2026). Broad-Scale Climatic Gradients Drive Multiple Facets of Scorpion Beta Diversity in Northeastern Brazil. Journal of Biogeography, 53(6), e70271. https://doi.org/10.1111/jbi.70271
