Latitudinal Gradients of Biodiversity: Theory and Empirical Patterns

TitleLatitudinal Gradients of Biodiversity: Theory and Empirical Patterns
Publication TypeJournal Article
Year of Publication2018
AuthorsWillig, MR, Presley, SJ
JournalEncyclopedia of the Anthropocene
Keywordsfunctional biodiversity, Geometric constraints, Phenetic biodiversity, phylogenetic biodiversity, Rapoport effect, scale, species richness, Species–area relationships, taxonomic biodiversity, α diversity, β diversity
AbstractIncreasing biodiversity from the poles toward the equator is one of the most well-established patterns in ecology and biogeography. This latitudinal gradient pertains to all major taxa and to all dimensions of biodiversity (i.e., taxonomic, functional, and phylogenetic). Latitudinal gradients in functional and phylogenetic biodiversity are strong, but not entirely a product of variation in species richness. These gradients have been attributed to many ecological and evolutionary mechanisms (e.g., environmental stability, productivity, area, evolutionary speed, diversification rate); however, it is unlikely that a single mechanism drives these patterns. Rather, a combination of mechanisms likely explain latitudinal gradients of biodiversity, with the relative importance of particular mechanisms being contingent on taxon, biogeographic region, or dimension of biodiversity.