Global priorities for conservation of reptilian phylogenetic diversity in the face of human impacts

Rikki Gumbs,Walter Jetz,Uri Roll,Claudia L Gray,Michael Hoffmann,Shai Meiri,Monika Böhm,Richard Grenyer,James Rosindell,Nisha R Owen

doi:10.1038/s41467-020-16410-6

Abstract

Phylogenetic diversity measures are increasingly used in conservation planning to represent aspects of biodiversity beyond that captured by species richness. Here we develop two new metrics that combine phylogenetic diversity and the extent of human pressure across the spatial distribution of species — one metric valuing regions and another prioritising species. We evaluate these metrics for reptiles, which have been largely neglected in previous studies, and contrast these results with equivalent calculations for all terrestrial vertebrate groups. We find that regions under high human pressure coincide with the most irreplaceable areas of reptilian diversity, and more than expected by chance. The highest priority reptile species score far above the top mammal and bird species, and reptiles include a disproportionate number of species with insufficient extinction risk data. Data Deficient species are, in terms of our species-level metric, comparable to Critically Endangered species and therefore may require urgent conservation attention.

Highlights

Phylogenetic diversity measures are increasingly used in conservation planning to represent aspects of biodiversity beyond that captured by species richness
We find that small ranges—key determinants of extinction risk—are phylogenetically clumped in lepidosaurs (Pagel’s test for phylogenetic signal: λ = 0.373, p ≪ 0.0001; Supplementary Fig. 1), and for lizards, amphisbaenians, and the tuatara and snakes independently, but not in turtles (λ = 0.12, p = 0.03) or crocodilians (λ = 0.048, p = 0.815; following correction for multiple testing, adjusted p-value threshold = 0.01)
We find that Data Deficient tetrapods have significantly longer terminal branches than those listed as Least Concern (4.3 MY), Near Threatened (4.3 MY) and Vulnerable (4.8 MY; adjusted p-values from ANOVA and Tukey HSD test < 0.001) and similar to Endangered (5.2 MY) and Critically Endangered (5.5 MY) species

Summary

Introduction

Phylogenetic diversity measures are increasingly used in conservation planning to represent aspects of biodiversity beyond that captured by species richness. We develop two new metrics that combine phylogenetic diversity and the extent of human pressure across the spatial distribution of species — one metric valuing regions and another prioritising species. We evaluate these metrics for reptiles, which have been largely neglected in previous studies, and contrast these results with equivalent calculations for all terrestrial vertebrate groups. PD is increasingly recognised as an important component of global biodiversity[9,10] linked to increased ecosystem productivity[11,12] and human well-being[4,13,14]. Policy Platform on Biodiversity and Ecosystem Services (IPBES) recognises PD as a key indicator of global trends in nature’s contribution to people[18]

Methods

Results

Conclusion