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1.
Conservation priority setting based on phylogenetic diversity has frequently been proposed but rarely implemented. Here, we define a simple index that measures the contribution made by different species to phylogenetic diversity and show how the index might contribute towards species-based conservation priorities. We describe procedures to control for missing species, incomplete phylogenetic resolution and uncertainty in node ages that make it possible to apply the method in poorly known clades. We also show that the index is independent of clade size in phylogenies of more than 100 species, indicating that scores from unrelated taxonomic groups are likely to be comparable. Similar scores are returned under two different species concepts, suggesting that the index is robust to taxonomic changes. The approach is applied to a near-complete species-level phylogeny of the Mammalia to generate a global priority list incorporating both phylogenetic diversity and extinction risk. The 100 highest-ranking species represent a high proportion of total mammalian diversity and include many species not usually recognised as conservation priorities. Many species that are both evolutionarily distinct and globally endangered (EDGE species) do not benefit from existing conservation projects or protected areas. The results suggest that global conservation priorities may have to be reassessed in order to prevent a disproportionately large amount of mammalian evolutionary history becoming extinct in the near future.  相似文献   

2.
The knowledge about the conservation status of species is an important data for conservation biology. Therefore, threatened species lists are a powerful tool for conservation planning and prioritization. Our objective is to compare the global, the national and state red lists of amphibians in Brazil. Threatened species were categorized according to their listing in one or several of these lists. We analyzed for true inconsistencies across lists in order to evaluate practical consequences of such incongruences on amphibian conservation in Brazil. We recorded a total of 61 threatened amphibian species in Brazil (across all red lists). Only one species, Phrynomedusa fimbriata, was listed as Extinct (both in IUCN, Brazil and S?o Paulo lists). A total of eleven endemic species are listed as threatened by the global red list, but do not appear in Brazil’s national red list, which represent an inconsistence among these lists. Besides that, the threat category of Thoropa lutzi and Thoropa petropolitana, two endemic species, differ among both lists, which also represents a problem between both lists. These mismatches may be due to several reasons such as different interpretation of the criteria; different methodologies used; different data availability on species; differences in the dates of assessments processes; the assessors’ attitudes to uncertainty; outdated red lists. Harmonization among red lists permits a better picture of threatened amphibian diversity across scales and to develop global, national and state plans to complement conservation actions in order to maximize the chance of success of these initiatives.  相似文献   

3.
The list of British Red Data birds (Batten et al. 1990) includes 117 species, 109 of which qualified on one or more quantitative criteria referring to rarity, localized distribution, population decline and international importance. A wealth of data on bird population levels and trends in the United Kingdom and Europe has recently become available, allowing refinement and improvement of the criteria for qualification. Here we propose that in assigning priorities for conservation action in the U.K. (Britain and Northern Ireland), three biological axes need to be considered: national threat (measured as rarity, localized distribution and population decline in the U.K.), international importance (the proportion of the European population in the U.K.) and international threat (European/global conservation status). Only the first two of these axes were considered by Batten et al. (1990). Each of these axes has been sub-divided into high, medium and low categories using quantitative thresholds, and from this we produce a national 'conservation cube' (three axes, each with three categories and thus 27 cells). Data permitting, every species in the U.K. can be allocated to one of these cells. We suggest that species high on either (or both) of the national or international threat axes be considered as species of high conservation priority (the red list) and that among the remainder those that rank at least medium on one of the axes be considered as of medium conservation priority (the amber list). All other species are of low conservation priority (the green list). We suggest that this three-axis model could be applicable to other taxa and countries.  相似文献   

4.
The global extinction crisis demands immediate action to conserve species at risk. However, if entire clades such as superfamilies are at risk due to shared evolutionary history, a shift towards conserving clades rather than individual species may be needed. Using phylogenetic autocorrelation analysis, we demonstrate that multiple kinds of extinction threat clump within the amphibian tree of life. Our study provides insight into how these threats may collectively influence the extinction risk of whole clades, consistent with the supposition that related species, with similar traits, share an intrinsic vulnerability to common kinds of threat. Most strikingly, we find a significant concentration of 'enigmatic' decline and critically endangered status within families of the hyloid frogs. This phylogenetic clumping of risk is also geographically concentrated, with most threats found in Central and South America, and Australia, coinciding with reported outbreaks of chytridiomycosis. We speculate that the phylogenetic clumping of threat represents, in part, shared extinction proneness due to shared evolutionary history. However, even if the phylogenetic clumping of threat were simply a by-product of shared geography, this concordance between phylogenetic and geographical patterns represents a prime opportunity. Where practical, we should implement conservation plans that focus on biogeographical regions where threatened clades occur, thereby improving our ability to conserve species. This approach could outperform the usual triage approach of saving individual species after they have become critically endangered.  相似文献   

5.
There is an increasing interest in measuring loss of phylogenetic diversity and evolutionary distinctiveness which together depict the evolutionary history of conservation interest. Those losses are assessed through the evolutionary relationships between species and species threat status or extinction probabilities. Yet, available information is not always sufficient to quantify the threat status of species that are then classified as data deficient. Data‐deficient species are a crucial issue as they cause incomplete assessments of the loss of phylogenetic diversity and evolutionary distinctiveness. We aimed to explore the potential bias caused by data‐deficient species in estimating four widely used indices: HEDGE, EDGE, PDloss, and Expected PDloss. Second, we tested four different widely applicable and multitaxa imputation methods and their potential to minimize the bias for those four indices. Two methods are based on a best‐ vs. worst‐case extinction scenarios, one is based on the frequency distribution of threat status within a taxonomic group and one is based on correlates of extinction risks. We showed that data‐deficient species led to important bias in predictions of evolutionary history loss (especially high underestimation when they were removed). This issue was particularly important when data‐deficient species tended to be clustered in the tree of life. The imputation method based on correlates of extinction risks, especially geographic range size, had the best performance and enabled us to improve risk assessments. Solving threat status of DD species can fundamentally change our understanding of loss of phylogenetic diversity. We found that this loss could be substantially higher than previously found in amphibians, squamate reptiles, and carnivores. We also identified species that are of high priority for the conservation of evolutionary distinctiveness.  相似文献   

6.
The need to protect and preserve biodiversity is a pressing issue and requires that conservation projects be based on solid foundations. Knowledge of species evolutionary history can serve as a tool to help guide conservation projects on the basis of evolutionary heritage. We used communities of Cladocera (Crustacea, Branchiopoda) in urban waterbodies to identify which sites should be prioritized for phylogenetic diversity conservation. Phylogenetic trees were inferred using DNA sequences from two mitochondrial genes. Furthermore, we also evaluated the consequences of phylogenetic uncertainty for identifying sites for conservation priority. Using results from Bayesian analyses, we considered the effect of uncertainty in the phylogenetic tree on phylogenetic diversity (PD) estimation. When phylogenetic uncertainty was taken into account, the conservation value of individual sites became uncertain and several potential comparisons between sites could not be supported. Consequently prioritization of one site over the other could not be defended in biodiversity conservation projects. Our study highlights the fact that accounting for phylogenetic uncertainty can alter the relative conservation priority of sites, as assessed by their phylogenetic diversity. Therefore, variability in the phylogenetic estimates should be consistently considered and integrated into estimates of phylogenetic diversity and conservation decisions to avoid making suboptimal choices.  相似文献   

7.
We present a review on the conservation status and population trends of the 372 amphibian species currently recognized for Mexico. We based our analyses on the information gathered by the International Union for the Conservation of Nature-the Global Amphibian Assessment (IUCN-GAA) as well as on available literature about imminent or potential threats to these organisms in Mexico. This country has the fifth largest amphibian fauna in the world and almost 58% of the species that inhabit this country are considered as threatened. We highlight the proportion of species per order, family, and genus that are currently under severe risk in Mexico. In addition, we prepared a detailed list of the main factors that are threatening amphibians in this country. Evidence is provided that the six main mechanisms that are globally leading amphibians to extinction (alien species, over-exploitation, land use change, global changes, pollution, and infectious diseases) are indeed currently operating in Mexico. We discuss the relative importance of each of these causes. We also highlight the paucity of quantitative studies that support the current conservation status of Mexican amphibian species.  相似文献   

8.
Phylogenetic systematics is heading for a renaissance where we shift from considering our phylogenetic estimates as a static image in a published paper and taxonomies as a hardcopy checklist to treating both the phylogenetic estimate and dynamic taxonomies as metadata for further analyses. The Open Tree of Life project (opentreeoflife.org) is developing synthesis tools for harnessing the power of phylogenetic inference and robust taxonomy to develop a synthetic tree of life. We capitalize on this approach to estimate a synthesis tree for the freshwater crayfish. The crayfish make an exceptional group to demonstrate the utility of the synthesis approach, as there recently have been a number of phylogenetic studies on the crayfishes along with a robust underlying taxonomic framework. Importantly, the crayfish have also been extensively assessed by an IUCN Red List team and therefore have accurate and up-to-date area and conservation status data available for analysis within a phylogenetic context. Here, we develop a synthesis phylogeny for the world''s freshwater crayfish and examine the phylogenetic distribution of threat. We also estimate a molecular phylogeny based on all available GenBank crayfish sequences and use this tree to estimate divergence times and test for divergence rate variation. Finally, we conduct EDGE and HEDGE analyses and identify a number of species of freshwater crayfish of highest priority in conservation efforts.  相似文献   

9.
Aim To define priority sets of ecoregions that should be sufficiently covered in a reserve system to represent all Neotropical carnivores (Mammalia: Carnivora) under three distinct conservation scenarios. Location The Neotropical region. Methods We used broad‐scale biogeographical data of species distribution to define priority sets of ecoregions for conservation of carnivores and mapped four species traits (phylogenetic diversity, body size, rarity and extinction risk), which were used as constraints in prioritization analyses, based on the complementarity concept. We proposed three scenarios: a very vulnerable one, one of species persistence and another of lower human impact. We used the simulated annealing algorithm to generate ecoregion‐irreplaceability pattern and to find the combinations of ecoregions in each conservation scenario. Results We found that only 8% of Neotropical ecoregions are needed to represent all 64 carnivore species at least once. Rain forest ecoregions harbour a greater amount of carnivore phylogenetic diversity, whereas the tropical Andes hold large‐bodied carnivores. Western and southern Neotropical ecoregions have more rare species as well as higher threat levels. In the lower human‐impact set, 12 ecoregions were needed to represent all species. These coincide only partially with those attained by other prioritization scenarios. In the very vulnerable and in the species persistence scenario, 14 and 12 ecoregions were represented, respectively, and the congruence between either one and the lower human‐impact set was fairly low. Shared ecoregions are located in Mexico, Costa Rica, northern Amazon and western Chile. Main conclusions Our results highlight areas of particular interest for the conservation of Neotropical carnivores. The inclusion of evolutionary and ecological traits in conservation assessments and planning helps to improve reserve networks and therefore to increase the effectiveness of proposed priority sets. We suggest that conservation action in the highlighted areas is likely to yield the best return of investments at the ecoregion scale.  相似文献   

10.
A joint analysis considering the world-wide distribution and threat status of Central European vascular plants was carried out to derive conservation priorities for threatened species. A list of 417 taxa is presented, which are threatened throughout Central Europe and/or show a predominantly Central European distribution. As a first step, all plants mentioned in Central European national Red Lists were included in a synoptic table, resulting in a total of 3255 taxa threatened or rare in at least one country. To select species with a high conservation priority, two parameters were estimated: threat status for Central Europe and a new category termed responsibility for the conservation of a species. As criteria for this second parameter, we used the proportion of Central Europe on the world range of a species, the position of Central Europe within this range, and its world-wide threat status. A simple category system including four responsibility categories is proposed. For all species selected, threat status and a responsibility assessment for the whole of Central Europe is given, as well as position and proportion of Central Europe on their world range. By comparison of threat status and responsibility, this list provides a background for assessing national conservation priorities as well as for making decisions about inclusion in international conventions on species conservation. This was shown by a comparison of the species selected using this approach with those included in the two most important European instruments for species conservation – the Berne Convention and the Habitats Directive.  相似文献   

11.
Huang D 《PloS one》2012,7(3):e34459
A substantial proportion of the world's living species, including one-third of the reef-building corals, are threatened with extinction and in pressing need of conservation action. In order to reduce biodiversity loss, it is important to consider species' contribution to evolutionary diversity along with their risk of extinction for the purpose of setting conservation priorities. Here I reconstruct the most comprehensive tree of life for the order Scleractinia (1,293 species) that includes all 837 living reef species, and employ a composite measure of phylogenetic distinctiveness and extinction risk to identify the most endangered lineages that would not be given top priority on the basis of risk alone. The preservation of these lineages, not just the threatened species, is vital for safeguarding evolutionary diversity. Tests for phylogeny-associated patterns show that corals facing elevated extinction risk are not clustered on the tree, but species that are susceptible, resistant or resilient to impacts such as bleaching and disease tend to be close relatives. Intensification of these threats or extirpation of the endangered lineages could therefore result in disproportionate pruning of the coral tree of life.  相似文献   

12.
Bridging the gap between the fossil record and conservation biology has recently become of great interest. The enormous number of documented extinctions across different taxa can provide insights into the extinction risk of living species. However, few studies have explored this connection. We used generalised boosted modelling to analyse the impact of several traits that are assumed to influence extinction risk on the stratigraphic duration of amphibian species in the fossil record. We used this fossil‐calibrated model to predict the extinction risk for living species. We observed a high consensus between our predicted species durations and the current IUCN Red List status of living amphibian species. We also found that today's Data Deficient species are mainly predicted to experience short durations, hinting at their likely high threat status. Our study suggests that the fossil record can be a suitable tool for the evaluation of current taxa‐specific Red Listing status.  相似文献   

13.
Guerrero is one of the most diverse states of Mexico, containing a large number of endemic and endangered amphibian species. However, it is one of the less protected and studied states of the country. Here, we determined the potential distribution of all amphibian species in a risk category present in Guerrero and defined priority areas for amphibian conservation in the state. We modelled the potential distribution of 32 species using the maximum entropy modelling algorithm. These models were used to define priority areas through systematic conservation planning tools. The most important variables explaining species’ potential distribution were measures of climate variability, particularly temperature seasonality. The priority areas for amphibian conservation identified covered a total area of 12,212.72 km2 and contained an important proportion (almost a third) of the cloud mountain forests of the state. The most important planning units for meeting species targets and the most important planning units in terms of biodiversity overlapped in approximately the same planning units, located in the biogeographic regions of the Sierra Madre del Sur and the Pacific Coast. Finally, from the total priority areas identified, only 0.31% (38.17 km2) is currently protected within the existing natural protected areas in Guerrero. Thus, we consider that it is essential to protect additional natural areas in the state. Areas Voluntarily Destined for Conservation (ADVC) may be a good option; however, action must be taken to ensure the legitimacy of the processes by the local people and to avoid privileging only certain members of the community.  相似文献   

14.

Prioritization is crucial in nature conservation, as land and financial resources are limited. Selection procedures must follow objective criteria, and not primarily subjective aspects, such as charisma. In this study, we assessed the level of charisma for all European butterflies. Based on these data, we analysed the charisma values of the species listed on the annexes of the EU Habitats Directive and of the species being of conservation priority according to criteria derived by three objective criteria: Species ecological specialisation, distribution, and threat. The mean level of charisma was higher for species of the EU Habitats Directive than for species of conservation priority and for not-listed species. Five of the twenty most charismatic species were also listed on the EU Habitats Directive, but none occurred on the list of species being of conservation priority. A trait space analysis revealed remarkable differences between the different species assortments: The species listed on the EU Habitats Directive covered a large trait space and included many species with high charismatic value, but low ecological and biogeographical relevance, while species of high conservation priority covered a restricted trait space and did not overlap with charismatic species. According to our findings, the selection of species for nature conservation still follows a mix of being aesthetic combined with some ecological criteria.

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15.
Few strategies for conservation seed banking consider current and climate threats simultaneously and few—if any—represent uncertainty inherent in the assessment process. Here we evaluate the vulnerability of 5148 populations of 71 rare plant species in the North American Central Highlands to current threat, threat from climate change, and their combination. We calculated priorities based on current threat using existing conservation status and protection, and priorities based on climate threat using ecological niche models and species-level traits related to reproduction and dispersal. Current- and climate-based priorities were integrated using a weighted average of rank priority. We managed uncertainty using either a precautionary strategy that avoids any extinctions or a resource-conservative strategy that directs attention to species known to be vulnerable with high certainty. Priorities based on current threats highlighted presently rare species while priorities based on climate threat emphasized presently common species. The location of geographic “hotspots” providing opportunities for efficient seed banking depended strongly on the weight of the climate module relative to the current module, the strategy used to handle uncertainty, and emissions scenario. Integrating threats highlighted some hotspots that were not identified using just current or climate threat, indicating the importance of considering current and climate threats simultaneously. Only the Central Basin of Tennessee, a known center of endemism, was consistently emphasized. We urge (1) integrating current and climate threats when designing seed-banking strategies; and (2) reporting of uncertainty in a manner that allows decision-makers to choose actions based on available resources and tolerable risk.  相似文献   

16.
Phylogenetics has a valuable role in the conservation of the flora of Western Australia particularly in the south-west where the complex evolutionary history has resulted in a diverse flora with both relictual and recently evolved components. Phylogenetic analysis contributes to conservation of plants through clarification of taxonomic status, identification of unique evolutionary lineages, determination of relictual and recently derived species, determination of phylogenetic value for conservation priority setting, and identifying phylogenetically independent comparisons between rare and widespread species. The contribution of phylogenetic analysis to these aspects of effective conservation management are discussed with examples from various species in Western Australia.  相似文献   

17.
Aim Our study aimed to determine priority areas for conservation investment with explicit consideration of the impacts of multiple threatening processes, and the dependencies that exist between actions required to abate these threats. Location Australia. Methods We analysed the return on investment for two different management actions aimed at reducing the impact of invasive species on the native fauna and flora of Australia. We focussed on the management of the European red fox (Vulpes vulpes) and European rabbit (Oryctolagus cuniculus) at two spatial scales: across 72 biogeographic regions of Australia and within one high‐priority biogeographic region. We considered each action independently and also explicitly accounted for the option of an integrated fox and rabbit management action. We accounted for the spatial distributions of the threatened species within our analysis and determined how this refined spatial information influenced both the priority areas and the timing of this investment. Results Integrated fox and rabbit management was identified as a higher priority than singular threat abatement in most bioregions, whereas rabbit control alone was the most frequent priority if dependencies between actions were ignored. At the regional scale, funding was entirely directed to integrated action when seven or more species within the priority region were impacted by more than one threat. The total allocation of funding and timing of initial investment remained relatively insensitive to differences in the spatial overlap of species distributions. Main conclusions Our findings indicate that prioritizing conservation actions without explicit consideration of the impacts of multiple threats can reduce the cost‐effectiveness of investments. The benefits expected from investment in abating one threat alone may be overestimated where other processes continue to threaten species persistence. We conclude that future attention should be directed to refining our understanding of the cost‐efficiencies delivered through integrated actions and institutional mechanisms to achieve their delivery.  相似文献   

18.
Understanding the relationships between species,communities,and biodiversity are important challenges in conservation ecology.Current biodiversity conservation activities usually focus on species that are rare,endemic,distinctive,or at risk of extinction.However,empirical studies of whether such species contribute more to aspects of biodiversity than common species are still relatively rare.The aim of the present study was to assess the contribution of individual amphibian species to different facets of biodiversity,and to test whether species of conservation interest contribute more to taxonomic,functional,and phylogenetic diversity than do species without special conservation status.To answer these questions,19 000 simulated random communities with a gradient of species richness were created by shuffling the regional pool of species inhabiting Emei Mountain.Differences of diversity values were then computed before and after removing individual species in these random communities.Our results indicated that although individual species contributed similarly to taxonomic diversity,their contribution to functional and phylogenetic diversity was more idiosyncratic.This was primarily driven by the diverse functional attributes of species and the differences in phylogenetic relationships among species.Additionally,species of conservation interest did not show a significantly higher contribution to any facet of biodiversity.Our results support the claims that the usefulness of metrics based only on species richness is limited.Instead,assemblages that include species with functional and phylogenetic diversity should be protected to maintain biodiversity.  相似文献   

19.
The conservation status of all the amphibians in China is analyzed,and the country is shown to be a global priority for conservation in comparison to many other countries of the world.Three Chinese regions are particularly rich in amphibian diversity:Hengduan,Nanling,and Wuyi mountains.Sala-manders are more threatened than frogs and toads.Several smaller families show a high propensity to become seriously threatened:Bombinatoridae,Cryptobranchidae,Hynobiidae and Salamandridae.Like other parts of the world,stream-breeding,high-elevation forest amphibians have a much higher likeli-hood of being seriously threatened.Habitat loss,pollution,and over-harvesting are the most serious threats to Chinese amphibians.Over-harvesting is a less pervasive threat than habitat loss,but it is more likely to drive a species into rapid decline.Five conservation challenges are mentioned with recommendations for the highest priority research and conservation actions.  相似文献   

20.
The conservation status of all the amphibians in China is analyzed, and the country is shown to be a global priority for conservation in comparison to many other countries of the world. Three Chinese regions are particularly rich in amphibian diversity: Hengduan, Nanling, and Wuyi mountains. Salamanders are more threatened than frogs and toads. Several smaller families show a high propensity to become seriously threatened: Bombinatoridae, Cryptobranchidae, Hynobiidae and Salamandridae. Like other parts of the world, stream-breeding, high-elevation forest amphibians have a much higher likelihood of being seriously threatened. Habitat loss, pollution, and over-harvesting are the most serious threats to Chinese amphibians. Over-harvesting is a less pervasive threat than habitat loss, but it is more likely to drive a species into rapid decline. Five conservation challenges are mentioned with recommendations for the highest priority research and conservation actions.  相似文献   

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