Global Patterns of Evolutionary Distinct and Globally Endangered Amphibians and Mammals

Isaac NJB (2013) Global Patterns of Evolutionary Distinct and Globally Endangered Amphibians and Mammals. PLoS ONE 8(5): e63582. doi:10.1371/journal.pone.0063582 Global Patterns of Evolutionary Distinct and Globally Endangered Amphibians and Mammals Kamran Safi 0 Katrina Armour-Marshall 0 Jonathan E. M. Baillie 0 Nick J. B. Isaac 0 Zoe G. Davies, University of Kent, United Kingdom 0 1 Department for Migration and Immuno-ecology, Max Planck Institute for Ornithology , Seewiesen, Germany , 2 Department of Biology, University of Konstanz , Konstanz, Germany , 3 Institute of Zoology, Zoological Society of London , London , United Kingdom , 4 Imperial College London , Berkshire , United Kingdom , 5 Natural Environment Research Council, Centre for Ecology and Hydrology , Oxfordshire , United Kingdom Background: Conservation of phylogenetic diversity allows maximising evolutionary information preserved within fauna and flora. The ''EDGE of Existence'' programme is the first institutional conservation initiative that prioritises species based on phylogenetic information. Species are ranked in two ways: one according to their evolutionary distinctiveness (ED) and second, by including IUCN extinction status, their evolutionary distinctiveness and global endangerment (EDGE). Here, we describe the global patterns in the spatial distribution of priority ED and EDGE species, in order to identify conservation areas for mammalian and amphibian communities. In addition, we investigate whether environmental conditions can predict the observed spatial pattern in ED and EDGE globally. Methods and Principal Findings: Priority zones with high concentrations of ED and EDGE scores were defined using two different methods. The overlap between mammal and amphibian zones was very small, reflecting the different phylobiogeographic histories. Mammal ED zones were predominantly found on the African continent and the neotropical forests, whereas in amphibians, ED zones were concentrated in North America. Mammal EDGE zones were mainly in South-East Asia, southern Africa and Madagascar; for amphibians they were in central and south America. The spatial pattern of ED and EDGE was poorly described by a suite of environmental variables. Conclusions: Mapping the spatial distribution of ED and EDGE provides an important step towards identifying priority areas for the conservation of mammalian and amphibian phylogenetic diversity in the EDGE of existence programme. - The current biodiversity crisis driven by anthropogenic action has led to a rate of species loss of up to a thousand times greater than that of background extinction [13]. One of the most significant issues now facing conservationists is how to best allocate limited resources for the best conservation outcome [4], given the uneven global distribution of biodiversity [5,6]. The main question considered when defining global conservation priorities is which geographical regions should be protected so as to maintain maximum biological diversity? [7]. Major institutional strategies of global conservation prioritisation focus on counts of irreplaceable and/or vulnerable species, and cover large portions of the earths land surface [5]. The priority regions identified by these strategies represent frameworks within which to allocate funding to national and local conservation projects. Species richness approaches are limited by their failure to take into account the ecological role of species in communities and the different contributions they make to ecological communities. Biodiversity value may thus be better estimated by its contribution to evolutionary history, where more evolutionarily distinct species have higher value [8,9]. Preservation of phylogenetic diversity allows scientists and conservationists to maximise information preserved within fauna and flora [9,10] (but see also [11]). The fact that evolutionarily distinct species generally have more divergent traits [12] suggests they might play a disproportionate role in ecosystem functioning [8,13]. Atkinson [14] observed that given two threatened taxa, one a species not closely related to other living species and the other a widespread and common species, it seems reasonable to give priority to the taxonomically distinct form. An additional argument for considering phylogenetic information in conservation is that extinction risk is not phylogenetically random [3]. Closely related species show similar threat levels; extinction risk is generally higher in species which are large, longlived, slowly reproducing and with specialised habitats and high levels of endemism [1,3,9]. Species predicted to survive into the future are likely to be widespread generalists (sometimes called weedy species), replacing those considered specialised, charismatic and distinctive [9]. To date, the protection of phylogenetic diversity has not yet been incorporated into priority setting approaches employed by conservation funding agencies or NGOs. Available research has indicated that priority regions such as biodiversity hotspots contain more phylogenetic diversity than expected by species numbers alone [15]. Recent studies also suggest that the loss of phylogenetic diversity is not spatially random and that regions such as the Amazonian basin and South East Asia are losing phylogenetic diversity faster than expected by random extinction [16]. Moreover, species contributing highly to phylogenetic diversity are no more likely to receive conservation attention than average [17]. Although there are many suggested measures of phylogenetic diversity at the community level [13,1820], only a few speciesbased measures exist and only one has been promoted as an institutional conservation programme [1,10]. The EDGE of Existence programme [21] raises conservation awareness and funding for species that are both evolutionary distinct (ED) and globally endangered (GE, i.e. they are highly threatened). The algorithm for generating ED and EDGE scores has been extensively tested [1,10,22] but the distribution of these metrics in space has not been mapped to date. Here, we identify priority areas based on risk of extinction and evolutionary uniqueness of species by investigating the global distribution of ED and EDGE species. Our goal is to identify the regions of the world where ED species (ED zones) and EDGE species (EDGE zones) are concentrated. We also seek to understand possible environmental factors that are correlated with high ED and EDGE, in order to shed light on the processes driving global patterns of phylogenetic diversity and threat. We used published ED and EDGE scores for mammals [1,10] and amphibians [22], which we obtained from the EDGE of existence programme [21] (see supplemental online material file Data S1). The range distribution data (range maps) for all species were obtained from IUCN [23] (accessed in July 2010 http:// www.iucnredlist.org/technical-documents/spatial-data) (Table 1). Each species (...truncated)