Both authors contributed equally to this work.
Unifying measures of biodiversity: understanding when richness and phylogenetic diversity should be congruent
Article first published online: 24 APR 2013
© 2013 John Wiley & Sons Ltd
Diversity and Distributions
Volume 19, Issue 7, pages 845–854, July 2013
How to Cite
Tucker, C. M., Cadotte, M. W. (2013), Unifying measures of biodiversity: understanding when richness and phylogenetic diversity should be congruent. Diversity and Distributions, 19: 845–854. doi: 10.1111/ddi.12087
- Issue published online: 13 JUN 2013
- Article first published online: 24 APR 2013
- NSERC. Grant Number: #386151
- conservation prioritization;
- evolutionary history;
- habitat protection;
- phylogenetic diversity;
- spatial distributions
Biogeographical theory and conservation valuation schemes necessarily involve assessing how biodiversity is distributed through space and ‘biodiversity’ encapsulates many different aspects of biological organization and information. While biogeography may try to explain biodiversity patterns, successful conservation strategies should attempt to maximize different aspects of diversity. Ultimately, diversity patterns are the product of evolutionary history, and research and conservation efforts seek to understand the unequal distribution of evolutionary history. For conservation efforts, results have been inconsistent as to whether species richness (SR) provides sufficient surrogacy for evolutionary history. Here, we provide a conceptual framework allowing for the direct comparison of taxonomic richness and phylogenetic diversity (PD), both in terms of their mechanistic relationship and the relationship between their spatial distributions.
We present a framework that relates regional SR, PD, biogeographically weighted evolutionary distinctiveness and biogeographically weighted SR. Further, we use simulations to illustrate how the size of the species pool, topological patterns within the phylogeny and autocorrelation in spatial distributions affect the correlation among metrics.
In regions that include both recently diversified groups and ancient species poor lineages, large species pools and low spatial autocorrelation, the correlation between biodiversity measures is lower than regions with low richness, balanced phylogenetic trees and high spatial autocorrelation.
We can now understand and predict when regional richness and PD should be strongly correlated. This congruency is the product of evolutionary and ecological processes that determine species pool membership and community assembly. Further, in regions where SR is not expected to be congruent with phylogenetic distinctiveness, re-examining how existing reserve networks protect the multiple aspects of biodiversity is critically important.