Understanding global patterns of mammalian functional and phylogenetic diversity

Area of Science:

• Ecology
• Evolutionary Biology
• Macroecology

Background:

• Species richness is a common but limited measure of biodiversity.
• Phylogenetic diversity (PD) and functional diversity (FD) offer alternatives by considering evolutionary and ecological differences.
• Global-scale relationships between these diversity measures remain under-investigated.

Purpose of the Study:

• To investigate the global-scale relationships between species richness, PD, and FD.
• To determine how environmental conditions influence the spatial congruence of these diversity metrics.
• To explore the implications for understanding mammalian diversity gradients.

Main Methods:

• Comparative analysis of species richness, PD, and FD across global datasets.
• Statistical modeling to assess the influence of environmental variables (e.g., temperature, seasonality) on diversity measure mismatches.
• Examination of residual variance to identify environmental drivers of spatial variation.

Main Results:

• PD and FD generally corroborate species richness as a measure of biodiversity.
• Environmental conditions significantly influence the spatial congruence between species richness, PD, and FD.
• PD increases with mean annual temperature, while FD decreases with reduced seasonality relative to PD.
• Tropical regions exhibit a functional diversity (FD) deficit, suggesting higher species packing in ecological space.

Conclusions:

• Global environmental gradients shape the spatial patterns of different biodiversity measures.
• The interplay between historical and ecological processes influences mammalian diversity gradients.
• Utilizing multiple diversity metrics is crucial for a comprehensive understanding of global biodiversity patterns.