Print PageBiodiversity, considered broadly, consists of many types of diversity, such as species richness, phylogenetic diversity, and trait or functional diversity. The relationship between phylogenetic diversity and species richness is well established. However, little is known about how trait diversity changes across lineages or spatially, including the general relationship between trait diversity and other measures of diversity. Using terrestrial mammals as a study system, and focusing on four well studied traits, we quantify the relationship between species richness, phylogenetic diversity, and trait diversity among major mammal lineages and spatially across the globe. We also contrast results using trait variance as the basic measure of trait diversity with results using a measure of trait diversity based on niche filling.
Results/Conclusions
Across lineages, phylogenetic diversity is generally a stronger correlate of trait diversity than species richness, however this varies depending upon whether traits show strong or weak phylogenetic signal. Spatially, trait diversity shows the strongest correlation with phylogenetic diversity in continental regions with unusually high phylogenetic diversity in proportion to their species richness, such as in mainland Africa. The converse of this result is that in many regions neither phylogenetic diversity nor species richness is a very good predictor of expected trait diversity. If a major goal of conservation is to preserve assemblages that have high trait or functional diversity, in many cases direct measures of trait diversity for species of interest will be absolutely essential to identifying these targets.
