Global patterns and mechanisms shaping dimensionality diversity in sharks

Abstract

An adequate description of biodiversity patterns requires an integration of different biological dimensions, including phylogenetic, functional, and taxonomic patterns. In this sense, dimensionality is defined as the number of complementary dimensions represented by metrics necessary to describe diversity in a non-redundant and effective way, with a correlation component (Evenness of Eigenvalues- EE) and the variation component (Importance Values- IV). Here we describe the dimensionality of global diversity patterns for sharks, based on several metrics of taxonomic, functional, and phylogenetic dimensions and the spatial patterns in dimensionality across marine biogeographic realms. We also investigated the relationship between dimensionality and emergent characteristics of each realm, including total richness, body size, area, latitude, and environmental dimensionality. Realm area and latitude were important ecological predictors of the dimensionality correlation component in realms. Phylogenetic diversity was the metric that contributed most to variation in the fundamental space of biodiversity, globally and within realms, highlighting the importance of evolutionary history in structuring shark communities. This is the first work on the diversity dimensionality of sharks, revealing important diversity patterns of the taxon and potential biological and ecological mechanisms related to the phenomenon of dimensionality.

Keywords

• Dimensionality
• Functional diversity
• Phylogenetic diversity
• Richness
• Regularity
• Sharks