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1.
Conserving and managing biodiversity in the face of ongoing global change requires sufficient evidence to assess status and trends of species distributions. Here, we propose novel indicators of biodiversity data coverage and sampling effectiveness and analyze national trajectories in closing spatiotemporal knowledge gaps for terrestrial vertebrates (1950 to 2019). Despite a rapid rise in data coverage, particularly in the last 2 decades, strong geographic and taxonomic biases persist. For some taxa and regions, a tremendous growth in records failed to directly translate into newfound knowledge due to a sharp decline in sampling effectiveness. However, we found that a nation’s coverage was stronger for species for which it holds greater stewardship. As countries under the post-2020 Global Biodiversity Framework renew their commitments to an improved, rigorous biodiversity knowledge base, our findings highlight opportunities for international collaboration to close critical information gaps.

Conserving and managing biodiversity in the face of ongoing global change requires sufficient evidence to assess status and trends of species distributions. This study analyzes national trajectories in closing spatiotemporal knowledge gaps for terrestrial vertebrates (1950-2019) based on novel indicators of data coverage and sampling effectiveness.  相似文献   

2.
《生物多样性公约》第十五次缔约方大会(COP15)将评估全球生物多样性保护已有进展, 审议并通过“2020年后全球生物多样性框架”, 后者是实现2050愿景“与自然和谐相处”的关键, 有助于达成联合国可持续发展的目标。生物多样性资金机制现在是将来也是实施全球生物多样性保护行动计划的重要保证。根据《生物多样性公约》信息交换所的数据, 目前各缔约方每年对本国生物多样性保护的投资额度占其当年国内生产总值(GDP)的比例比较小。中国作为发展中国家, 2015年时生物多样性保护资金投入占GDP比例为0.255%, 在世界各国中处于比较高的水平。近年中国对生物多样性保护的投入连年增加, 2019年时已经达约0.6%。有研究表明, 目前全球每年生物多样性保护资金的缺口至少500亿美元, 未来十年还有更大的资金缺口, 而且当前已有生物多样性资金渠道比较单一, 并存在一些短板, 远远不能满足生物多样性保护行动的要求, 急需建立新的资金机制, 调动更多资源, 推动2030年生物多样性保护任务和目标的实现。《生物多样性公约》的资金机制可以与包括《联合国气候变化框架公约》在内的其他相关环境公约协同增效, 比如基于自然的解决方案将生物多样性保护与气候变化减缓等环境目标联系起来。中国作为COP15的东道国, 有积极协调磋商的责任, 力求在大会上推动形成一个新的资金机制, 即全球生物多样性保护基金, 为“2020年后全球生物多样性框架”的实施保驾护航。新的生物多样性保护资金机制将独立于现有的生物多样性保护资金机制, 具有多样化投资渠道并引入绩效评估机制, 将经费与任务目标关联, 提高资金的使用效率, 支持发展中国家的生物多样性保护行动。  相似文献   

3.
农业生物多样性是《生物多样性公约》(以下简称《公约》)履约的核心议题之一, 对世界粮食安全、农业可持续发展以及实现碳中和具有重要实践意义。然而, 越来越多的研究表明, 由于人口的持续增长和饮食结构的根本性改变, 农业扩张已成为生物多样性丧失的主要驱动力之一。本文基于《公约》条款、第二次至第十四次缔约方大会相关决定、生物多样性和生态系统服务政府间科学与政策平台评估报告、第五版《全球生物多样性展望》(GBO-5)等内容, 系统梳理了《公约》谈判中农业生物多样性的履约进展和演变进程, 分析了农业生物多样性面临的严峻形势及存在问题。在此基础上, 从深入农业生物多样性相关指标研究、基于自然的解决方案、实现农业绿色可持续发展以及推动非国家利益相关方参与等层面, 就加强中国农业生物多样性保护工作提出建议, 以期有利于塑造中国良好对外形象, 也为维护世界农业稳定和粮食安全、推动《公约》第十五次缔约方大会(COP15)的顺利召开和成果达成奠定科学基础。  相似文献   

4.
The EU''s Biodiversity Strategy for 2030 makes great promises about halting the decline of biodiversity but it offers little in terms of implementation. Subject Categories: S&S: Economics & Business, Ecology, S&S: Ethics

Earth is teeming with a stunning variety of life forms. Despite hundreds of years of exploration and taxonomic research, and with 1.2 million species classified, we still have no clear picture of the real extent of global biodiversity, with estimates ranging from 3 to 100 million species. A highly quoted—although not universally accepted—study predicted some 8.7 million species, of which about 2.2 million are marine (Mora et al, 2011). Although nearly any niche on the surface of Earth has been colonized by life, species richness is all but evenly distributed. A large share of the known species is concentrated in relatively small areas, especially in the tropics (Fig 1). Ultimately, it is the network of the interactions among life forms and the physical environment that make up the global ecosystem we call biosphere and that supports life itself.Open in a separate windowFigure 1Biological hotspots of the worldA total of 36 currently recognized hotspots make up < 3% of the planet''s land area but harbor half of the world''s endemic plant species and 42% of all terrestrial vertebrates. Overall, hotspots have lost more than 80% of their original extension. Credit: Richard J. Weller, Claire Hoch, and Chieh Huang, 2017, Atlas for the End of the World, http://atlas‐for‐the‐end‐of‐the‐world.com/. Reproduced with permission.Driven by a range of complex and interwoven causes–such as changes in land and sea use, habitat destruction, overexploitation of organisms, climate change, pollution, and invasive species–biodiversity is declining at an alarming pace. A report by the Intergovernmental Science‐Policy Platform on Biodiversity and Ecosystem Services (IPBES) issued a clear warning: “An average of around 25 per cent of species in assessed animal and plant groups are threatened, suggesting that around 1 million species already face extinction, many within decades, unless action is taken to reduce the intensity of drivers of biodiversity loss. Without such action, there will be a further acceleration in the global rate of species extinction, which is already at least tens to hundreds of times higher than it has averaged over the past 10 million years” (IPBES, 2019) (Fig 2). Although focused on a smaller set of organisms, a more recent assessment by WWF has reached similar conclusions. Their Living Planet Index, that tracks the abundance of thousands of populations of mammals, birds, fish, reptiles, and amphibians around the world, shows a stark decline in monitored populations (WWF, 2020). As expected, the trend of biodiversity decline is not homogeneous with tropical areas paying a disproportionately high price, mostly because of unrestrained deforestation and exploitation of natural resources.Open in a separate windowFigure 2The global, rapid decline of biodiversity(A) Percentage of species threatened with extinction in taxonomic groups that have been assessed comprehensively, or through a “sampled” approach, or for which selected subsets have been assessed by the IUCN Red List of Threatened Species. Groups are ordered according to the best estimate, assuming that data‐deficient species are as threatened as non‐data deficient species. (B) Extinctions since 1500 for vertebrate groups. (C) Red List Index of species survival for taxonomic groups that have been assessed for the IUCN Red List at least twice. A value of 1 is equivalent to all species being categorized as Least Concern; a value of zero is equivalent to all species being classified as Extinct. Data for all panels from www.iucnredlist.org. Reproduced from (IPBES, 2019), with permission.
Driven by a range of complex and interwoven causes […] biodiversity is declining at an alarming pace.
Against this dire background, the EU has drafted a Biodiversity Strategy 2030, an ambitious framework aimed to tackling the key reasons behind biodiversity loss. The plan hinges around a few main elements, such as the establishment of protected areas for at least 30% of Europe''s lands and seas (Fig 3); a significant increase of biodiversity‐rich landscape features on agricultural land by establishing buffer zones like hedges and fallow fields; halting and reversing the decline of pollinators; and planting 3 billion trees by 2030 (https://ec.europa.eu/info/strategy/priorities‐2019‐2024/european‐green‐deal/actions‐being‐taken‐eu/eu‐biodiversity‐strategy‐2030_en). The budget for implementing these measures was set at €20 billion per year.Open in a separate windowFigure 3Natura 2000, the EU''s network of protected areasIn 2019, 18% of land in the EU was protected as Natura 2000, with the lowest share of protected land in Denmark (8%) and the highest in Slovenia (38%). In 2019, the largest national network of terrestrial Natura 2000 sites was located in Spain, covering 138,111 km2, followed by France (70,875 km2) and Poland (61,168 km2). Reproduced from Eurostat: https://ec.europa.eu/eurostat/statistics‐explained/index.php?title=Main_Page “Nature is vital for our physical and mental wellbeing, it filters our air and water, it regulates the climate and it pollinates our crops. But we are acting as if it didn''t matter, and losing it at an unprecedented rate”, said Virginijus Sinkevičius, Commissioner for the Environment, Oceans and Fisheries, at the press launch of the new EU action (https://ec.europa.eu/commission/presscorner/detail/en/ip_20_884). “This new Biodiversity Strategy builds on what has worked in the past, and adds new tools that will set us on a path to true sustainability, with benefits for all. The EU''s aim is to protect and restore nature, to contribute to economic recovery from the current crisis, and to lead the way for an ambitious global framework to protect biodiversity around the planet”.Environmental groups and other stakeholders have welcomed the EU''s pledge in principle. “This is a unique opportunity to shape a new society in harmony with nature”, applauded Wetlands International. “We must not forget that the biodiversity and climate crisis is a much bigger and persistent challenge for humanity than COVID‐19”, (https://europe.wetlands.org/news/welcoming‐the‐eu‐biodiversity‐strategy‐for‐2030/). EuroNatur, a foundation focused on conservation, stated that the goals set out by the new strategy provide a strong basis for improving the state of nature in the EU (www.euronatur.org).Alongside the voices of praise, however, many have expressed concerns that the strategy could turn into a little more than a wish list. “The big issue of the strategy is that while setting a goal for financial funds, the EU does not specify where the money is supposed to come from. It only says it should include ‘EU funds and national and private funding’”, commented the European Wilderness Society, an environmental advocacy non‐profit organization headquartered in Tamsweg, Austria. “Goals are important, but do not create change without an organized and sustainable implementation. It''s a good and ambitious document, but what is also obvious is the lack of strategy of how to implement it, and a lack of discussion of why previous documents of this type failed” (https://wilderness‐society.org/ambitious‐eu‐biodiversity‐strategy‐2030/).
Alongside the voices of praise, however, many have expressed concerns that the strategy could turn into a little more than a wish list.
The Institute for European Environmental Policy (IEEP) is on the same page. The sustainability think‐tank based in Brussels and London noted that the outgoing EU 2020 biodiversity strategy showed major implementation problems, especially because of lack of engagement at national level and of ad hoc legislation supporting the meeting of key targets. Therefore, “[it] can be argued that a legally binding approach to the biodiversity governance framework is urgently needed unless Member States and other key stakeholders can show greater intrinsic ownership to deliver on agreed objectives”, (https://ieep.eu/news/first‐impressions‐of‐the‐eu‐biodiversity‐strategy‐to‐2030). In addition, IEEP remarked that money is an issue, since the €20 billion figure appears more as an estimate than a certified obligation.“The intentions of the Commission are good and the strategy contains a number of measures and targets that can really make a difference. However, implementation depends critically on the member states and experiences with the Common Agricultural Policy the past decade or so have taught us that many of them are more interested in short‐term economic objectives than in safeguarding the natural wealth of their country for future generations”, commented David Kleijn, an ecologist and nature conservation expert at the Wageningen University, the Netherlands. “I think it is important that we now have an ambitious Biodiversity Strategy but at the same time I have little hope that we will be able to achieve its objectives”.
I think it is important that we now have an ambitious Biodiversity Strategy but at the same time I have little hope that we will be able to achieve its objectives.
There is further criticism against specific measures, such as the proposal of planting 3 billion trees. “To have lots of trees planted in an area does not necessarily translate into an increase of biodiversity. Biodiverse ecosystems are the result of million years of complex multi‐species interactions and evolutionary processes, which are not as easy to restore”, explained plant ecologist Susana Gómez‐González, from the University of Cádiz, Spain. Planting a large number of trees is a too simplistic approach for saving European forests from the combined effects of excessive anthropic pressure and climate change, and could even have detrimental effects (see Box 1). More emphasis should be placed instead in reducing tree harvesting in sensitive areas and in promoting natural forest renewal processes (Gómez‐González et al, 2020). “For a biodiversity strategy, increasing the number of trees, or even increasing the forest area, should not be an objective; priority should be given to the conservation and restoration of natural ecosystems, forests and non‐forests”, Gómez‐González said.In other cases, it could be difficult, if not impossible, to reach some of the goals because of lack of information. For example, one of the roadmap''s targets is to restore at least 25,000 km of Europe''s rivers back to free‐flowing state. However, the number of barriers dispersed along European rivers will probably prevent even getting close to the mark. An international research team has collected detailed information on existing instream barriers for 147 rivers in 36 European countries, coming up with the impressive figure of over 1.2 million obstacles that inevitably impact on river ecosystems, affecting the transport and dispersion of aquatic organisms, nutrients, and sediments (Belletti et al, 2020). Existing inventories mainly focused on dams and other large barriers, while, in fact, a large number of artificial structures are much smaller, such like weirs, locks, ramps, and fords. As a result, river fragmentation has been largely underestimated, and the models used to plan flow restoration might be seriously flawed. “To avoid ‘death by a thousand cuts’, a paradigm shift is necessary: to recognize that although large dams may draw most of the attention, it is the small barriers that collectively do most of the damage. Small is not beautiful”, concluded the authors (Belletti et al, 2020).

Box 1: Why many trees don''t (always) make a forestForests are cathedrals of biodiversity. They host by far the largest number of species on land, which provide food and essential resources for hundreds of millions of people worldwide. However, forests are disappearing and degrading at an alarming pace. The loss of these crucial ecosystems has given new impulses to a variety of projects aimed at stopping this devastation and possibly reversing the trend.Once it is gone, can you rebuild a forest? Many believe the answer is yes, and the obvious solution is to plant trees. Several countries have thus launched massive tree‐planting programs, notably India and Ethiopia, where 350 million trees have been planted in single day (https://www.unenvironment.org/news‐and‐stories/story/ethiopia‐plants‐over‐350‐million‐trees‐day‐setting‐new‐world‐record). The World Economic Forum has set up its own One Trillion Tree initiative (https://www.1t.org/) “to conserve, restore, and grow one trillion trees by 2030”. Launched in January last year at Davos, 1t.org was conceived as a platform for governments, companies and NGOs/civil society groups to support the UN Decade on Ecosystem Restoration (2021–2030). The initiative has been christened by renowned naturalist Jane Goodall, who commented: “1t.org offers innovative technologies which will serve to connect tens of thousands of small and large groups around the world that are engaged in tree planting and forest restoration”, (https://www.weforum.org/agenda/2020/01/one‐trillion‐trees‐world‐economic‐forum‐launches‐plan‐to‐help‐nature‐and‐the‐climate/).However, things are way more complicated than they appear: large‐scale tree planting schemes are rarely a viable solution and can even be harmful. “[A] large body of literature shows that even the best planned restoration projects rarely fully recover the biodiversity of intact forests, owing to a lack of sources of forest‐dependent flora and fauna in deforested landscapes, as well as degraded abiotic conditions resulting from anthropogenic activities”, commented Karen Holl from the University of Caliornia, Santa Cruz, and Pedro Brancalion from the University of São Paulo (Holl & Brancalion, 2020). A common problem of tree plantations, for example, is the low survival rate of seedlings, mostly because the wrong tree species are selected and due to poor maintenance after planting. Moreover, grasslands and savannas, which are often targeted for establishing new forests, are themselves treasure troves of biodiversity. Ending indiscriminate deforestation, improving the protection of existing forests, and promoting their restoration would therefore be a more efficient strategy to preserve biodiversity in the shorter term. If tree planting is indeed necessary, it should be well planned by selecting the right areas for reforestation, using suitable tree species that can maximize biodiversity, and involving local populations to maintain the plantations, Holl and Brancalion argue (Holl & Brancalion, 2020).

…even the best planned restoration projects rarely fully recover the biodiversity of intact forests, owing to a lack of sources of forest‐dependent flora and fauna in deforested landscapes…
The health of soil, where a high proportion of biodiversity is hosted, is another problem the new strategy should address in a more focused manner. “In my opinion, the EU Biodiversity Strategy is already a leap forward in terms of policy interest in soils in general and in soil biodiversity in particular. Compared with other nations/regions of the world, Europe is by far in the forefront regarding this issue”, commented Carlos António Guerra at the German Centre for Integrative Biodiversity Research (iDiv) in Leipzig, Germany, and Co‐leader of the Global Soil Biodiversity Observation Network (https://geobon.org/bons/thematic‐bon/soil‐bon/). “Nevertheless, the connection between soil biodiversity and ecological functions needs further commitments. Soils allow for horizontal integration of several policy agendas, from climate to agriculture and, very importantly, nature conservation. This is not explicit in the EU Biodiversity Strategy in regard to soils”. It remains to be seen if EU restoration plan will emphasize soil biodiversity, or consider it as a mere side effect of other initiatives, Guerra added. “A soil nature conservation plan should be proposed”, he said. “Only such a plan, that implies that current and future protected areas have to consider, describe and protect their soil biodiversity would make a significant push to help protect such a valuable resource”.More generally, research shows that the current paradigm of protection must be shifted to prevent further losses to biodiversity. In fact, an analysis of LIFE projects—a cornerstone of EU nature protection—found that conservation efforts are extremely polarized and strongly taxonomically biased (Mammola et al, 2020). From 1992 to 2018, investment in vertebrates was sixfold higher than that for invertebrates, with birds and mammals alone accounting for 72% of the targeted species and 75% of the total budget. In relative terms, investment per species for vertebrates has been 468 times higher than for invertebrates (Fig 4). There is no sound scientific reasoning behind this uneven conservation attention, but just popularity. “[T]he species covered by a greater number of LIFE projects were also those which attracted the most interest online, suggesting that conservation in the EU is largely driven by species charisma, rather than objective features”, the researchers wrote (Mammola et al, 2020).Open in a separate windowFigure 4Taxonomic bias in EU fauna protection effortsBreakdown of the number of projects (A) and budget allocation (B) across main animal groups covered by the LIFE projects (n = 835). (C) The most covered 30 species of vertebrates (out of 410) and invertebrates (out of 78) in the LIFE projects analyzed (n = 835). The vertical bar represents monetary investment and the blue scatter line the number of LIFE projects devoted to each species. Reproduced from (Mammola et al, 2020), with permission.  相似文献   

5.
Habitat loss is the most prevalent threat to biodiversity in North America. One of the most threatened landscapes in the United States is the sagebrush (Artemisia spp.) ecosystem, much of which has been fragmented or converted to non‐native grasslands via the cheatgrass‐fire cycle. Like many sagebrush obligates, greater sage‐grouse (Centrocercus urophasianus) depend upon sagebrush for food and cover and are affected by changes to this ecosystem. We investigated habitat selection by 28 male greater sage‐grouse during each of 3 years after a 113,000‐ha wildfire in a sagebrush steppe ecosystem in Idaho and Oregon. During the study period, seeding and herbicide treatments were applied for habitat restoration. We evaluated sage‐grouse responses to vegetation and post‐fire restoration treatments. Throughout the 3 years post‐fire, sage‐grouse avoided areas with high exotic annual grass cover but selected strongly for recovering sagebrush and moderately strongly for perennial grasses. By the third year post‐fire, they preferred high‐density sagebrush, especially in winter when sagebrush is the primary component of the sage‐grouse diet. Sage‐grouse preferred forb habitat immediately post‐fire, especially in summer, but this selection preference was less strong in later years. They also selected areas that were intensively treated with herbicide and seeded with sagebrush, grasses, and forbs, although these responses varied with time since treatment. Wildfire can have severe consequences for sagebrush‐obligate species due to loss of large sagebrush plants used for food and for protection from predators and thermal extremes. Our results show that management efforts, including herbicide application and seeding of plants, directed at controlling exotic annual grasses after a wildfire can positively affect habitat selection by sage‐grouse.  相似文献   

6.
赵阳  李宏涛 《生物多样性》2022,30(11):22049-46
近年来我国每年发布《企业社会责任报告》近2,000份, 有相当比例包含生物多样性内容。但长期以来, 披露内容的实质性与可信度严重不足, 亟需引导、规范和审核。本文探讨建立我国企业生物多样性信息公开透明机制, 旨在解决两个主要问题: 一是风险规避, 二是资源调动。本文根据《生物多样性公约》相关规定, 首先梳理企业生物多样性信息披露国内外进展, 指出存在内容碎片化, 科学指标缺失, 结果难以比较, 投入产出、同业及历史数据缺乏比对分析等不足。其次, 采用5个生物多样性指标, 进一步对《企业社会责任报告评估指数》研究发现: 不同行业差异化明显、金融机构催化作用凸显、重视纳入制度战略框架、报告内容同质化严重、定性描述多于定量分析、货币化核算方法缺失、资金投入信息披露保守、未经第三方独立审核等特点。最后, 提出提高企业透明度的4项建议: (1)加强顶层设计纳入, (2)改进环境政策指引, (3)优化金融激励措施, (4)强化公司能力建设。这将为政府和金融部门量化生态影响, 管控投资风险, 实施扩大生物多样性融资决策提供支持。  相似文献   

7.
Environmental DNA metabarcoding is becoming a predominant tool in biodiversity assessment, as this time‐ and cost‐efficient tactics have the ability to increase monitoring accuracy. As a worldwide distributed genus, Rheocricotopus Brundin, 1956 still does not possess a complete and comprehensive global DNA barcode reference library for biodiversity monitoring. In the present study, we compiled a cytochrome c oxidase subunit 1 (COI) DNA barcode library of Rheocricotopus with 434 barcodes around the world, including 121 newly generated DNA barcodes of 32 morphospecies and 313 public barcodes. Automatic Barcode Gap Discovery (ABGD) was applied on the 434 COI barcodes to provide a comparison between the operational taxonomic units (OTU) number calculated from the Barcode Index Number (BIN) with the “Barcode Gap Analysis” and neighbor‐joining (NJ) tree analysis. Consequently, these 434 COI barcodes were clustered into 78 BINs, including 42 new BINs. ABGD yielded 51 OTUs with a prior intraspecific divergence of Pmax = 7.17%, while NJ tree revealed 52 well‐separated clades. Conservatively, 14 unknown species and one potential synonym were uncovered with reference to COI DNA barcodes. Besides, based on our ecological analysis, we discovered that annual mean temperature and annual precipitation could be considered as key factors associated with distribution of certain members from this genus. Our global DNA barcode reference library of Rheocricotopus provides one fundamental database for accurate species delimitation in Chironomidae taxonomy and facilitates the biodiversity monitoring of aquatic biota.  相似文献   

8.
The first few words of the title of this symposium are “Anchoring Biodiversity Information”. In order to properly anchor anything for a long-lasting future, a solid foundation needs to have been laid. For the zoological portion of biodiversity information, that firm foundation is best exemplified in the works of Charles Davies Sherborn. This man, like others of his ilk, was intimately focused on indexing names. This incredible focus was a life-long passion for him and culminated in his 9500-page Index Animalium of over 400,000 names of animals. This Index represents not only one of the most prodigious efforts in publication by a single man and the single most important reference to names in zoology, but a permanent legacy to the efforts of an indexer that proved to be an inspiration to many.  相似文献   

9.
《生物多样性公约》第十五次缔约方大会(COP15)计划于2021年在云南昆明召开, 大会将评估《2011-2020年生物多样性战略计划》执行情况及实施进展。如能达成协议, 将出台“2020年后全球生物多样性框架”, 作为指导2020年之后全球生物多样性保护的最新纲领性文件。这是生物多样性保护国际进程的一个里程碑, 也是展现中国以及云南多年来生物多样性保护成效的重要契机。作为中国生物多样性最为丰富的省份和具有全球意义的生物多样性关键地区之一, 云南在生物多样性保护方面投入巨大努力, 在全国较早发布省级《生物多样性保护战略与行动计划(2012-2030年)》、开创地方立法先河、率先试点建设国家公园、较早开展县域生物多样性本底调查与评估研究工作、建立了首个国家级野生生物种质资源库等, 在就地保护、迁地保护、重大生态工程等众多领域都取得显著成效。本文在梳理云南生物多样性保护进展与成就的基础上, 对保护成效进行了评估, 并有针对性地探讨了云南生物多样性保护未来发展方向及重大意义, 加强全省农业生物多样性的保护与可持续利用、发挥跨境生物多样性保护及减贫示范作用、协调发展生物多样性保护与少数民族传统知识保护等方面是云南省生物多样性保护今后发展的重要方向, 同时本文也为进一步促进云南生物多样性保护与管理提供了基础资料, 并为COP15提供地方履约实例。  相似文献   

10.
For community ecologists, “neutral or not?” is a fundamental question, and thus, rejecting neutrality is an important first step before investigating the deterministic processes underlying community dynamics. Hubbell''s neutral model is an important contribution to the exploration of community dynamics, both technically and philosophically. However, the neutrality tests for this model are limited by a lack of statistical power, partly because the zero‐sum assumption of the model is unrealistic. In this study, we developed a neutrality test for local communities that implements non‐zero‐sum community dynamics and determines the number of new species (N sp) between observations. For the non‐zero‐sum neutrality test, the model distributed the expected N sp, as calculated by extensive simulations, which allowed us to investigate the neutrality of the observed community by comparing the observed N sp with distributions of the expected N sp derived from the simulations. For this comparison, we developed a new “non‐zero‐sum N sp test,” which we validated by running multiple neutral simulations using different parameter settings. We found that the non‐zero‐sum N sp test rejected neutrality at a near‐significance level, which justified the validity of our approach. For an empirical test, the non‐zero‐sum N sp test was applied to real tropical tree communities in Panama and Malaysia. The non‐zero‐sum N sp test rejected neutrality in both communities when the observation interval was long and N sp was large. Hence, the non‐zero‐sum N sp test is an effective way to examine neutrality and has reasonable statistical power to reject the neutral model, especially when the observed N sp is large. This unique and simple approach is statistically powerful, even though it only employs two temporal sequences of community data. Thus, this test can be easily applied to existing datasets. In addition, application of the test will provide significant benefits for detecting changing biodiversity under climate change and anthropogenic disturbance.  相似文献   

11.
Authentic research experiences (AREs) are a powerful strategy for inspiring and retaining students in science, technology, engineering, and math (STEM) fields. However, recent demand for virtual learning has emphasized the need for remote AREs that also foster a sense of community and interpersonal connections among participants. Here, we describe an ARE activity that leverages digitized diet data from natural history collections to provide students with collaborative research experience across any learning environment. Using magnified photographs of frog stomach contents collected in the Peruvian Amazon, we designed an open‐source “bowl game” competition that challenges students to identify, measure, and compare diet items across vouchered frog specimens (“Batrachian Barf Bowl”). To demonstrate learning outcomes, we ran this activity with 39 herpetology class students from the University of Notre Dame and the University of Michigan. We used pre‐ and post‐activity assessments to evaluate effectiveness, scientific accuracy of results, and impact on student well‐being. With minimal preparation and training in invertebrate identification, students were successful in identifying hundreds of frog diet items to taxonomic order, although accuracy varied among clades (global accuracy ~70%). While we found no difference in science identity, community, or self‐efficacy between the two institutions at either time point (pre‐ and post‐activity), we found that well‐being was significantly higher for both sets of students after the activity. Overall, this approach offers a model for combining active learning with museum collections to provide experiential research opportunities that highlight the power of scientific collaboration.  相似文献   

12.
Glia contribute to synapse elimination through phagocytosis in the central nervous system. Despite the important roles of this process in development and neurological disorders, the identity and regulation of the "eat‐me" signal that initiates glia‐mediated phagocytosis of synapses has remained incompletely understood. Here, we generated conditional knockout mice with neuronal‐specific deletion of the flippase chaperone Cdc50a, to induce stable exposure of phosphatidylserine, a well‐known "eat‐me" signal for apoptotic cells, on the neuronal outer membrane. Surprisingly, acute Cdc50a deletion in mature neurons causes preferential phosphatidylserine exposure in neuronal somas and specific loss of inhibitory post‐synapses without effects on other synapses, resulting in abnormal excitability and seizures. Ablation of microglia or the deletion of microglial phagocytic receptor Mertk prevents the loss of inhibitory post‐synapses and the seizure phenotype, indicating that microglial phagocytosis is responsible for inhibitory post‐synapse elimination. Moreover, we found that phosphatidylserine is used for microglia‐mediated pruning of inhibitory post‐synapses in normal brains, suggesting that phosphatidylserine serves as a general "eat‐me" signal for inhibitory post‐synapse elimination.  相似文献   

13.
“2020年后全球生物多样性框架”是当前《生物多样性公约》谈判的焦点议题之一。本文阐述了框架制定的背景, 介绍了“2020年后全球生物多样性框架”不限成员名额工作组(Open Ended Working Group, OEWG),的谈判过程, 综合分析了缔约方在各有关磋商进程中的观点, 以及目前缔约方对框架各个要素的共识和分歧, 评估了框架的制定进展, 并就框架的设计提出四点展望: (1)阐明转型变革的具体实施路径; (2)平衡反映公约三大目标; (3)加强与其他全球治理进程的协同; (4)强化框架对全球及缔约方履约进展的评估和审查。最后提出对我国的建议: (1)及时更新国家生物多样性战略与行动计划(National Biodiversity Strategies and Action Plans, NBSAP); (2)加强国内生物多样性工作的协调; (3)继续加强生态环境执法和责任机制。为缔约方更好参与框架制定进程, 深入了解框架及其磋商进展提供参考, 并为下一步框架制定提供参考。  相似文献   

14.
During implantation, the murine embryo transitions from a “quiet” into an active metabolic/proliferative state, which kick‐starts the growth and morphogenesis of the post‐implantation conceptus. Such transition is also required for embryonic stem cells to be established from mouse blastocysts, but the factors regulating this process are poorly understood. Here, we show that Ronin plays a critical role in the process by enabling active energy production, and the loss of Ronin results in the establishment of a reversible quiescent state in which naïve pluripotency is promoted. In addition, Ronin fine‐tunes the expression of genes that encode ribosomal proteins and is required for proper tissue‐scale organisation of the pluripotent lineage during the transition from blastocyst to egg cylinder stage. Thus, Ronin function is essential for governing the metabolic capacity so that it can support the pluripotent lineage’s high‐energy demands for cell proliferation and morphogenesis.  相似文献   

15.
SARS‐CoV‐2 is a newly emerged coronavirus that caused the global COVID‐19 outbreak in early 2020. COVID‐19 is primarily associated with lung injury, but many other clinical symptoms such as loss of smell and taste demonstrated broad tissue tropism of the virus. Early SARS‐CoV‐2–host cell interactions and entry mechanisms remain poorly understood. Investigating SARS‐CoV‐2 infection in tissue culture, we found that the protease TMPRSS2 determines the entry pathway used by the virus. In the presence of TMPRSS2, the proteolytic process of SARS‐CoV‐2 was completed at the plasma membrane, and the virus rapidly entered the cells within 10 min in a pH‐independent manner. When target cells lacked TMPRSS2 expression, the virus was endocytosed and sorted into endolysosomes, from which SARS‐CoV‐2 entered the cytosol via acid‐activated cathepsin L protease 40–60 min post‐infection. Overexpression of TMPRSS2 in non‐TMPRSS2 expressing cells abolished the dependence of infection on the cathepsin L pathway and restored sensitivity to the TMPRSS2 inhibitors. Together, our results indicate that SARS‐CoV‐2 infects cells through distinct, mutually exclusive entry routes and highlight the importance of TMPRSS2 for SARS‐CoV‐2 sorting into either pathway.  相似文献   

16.
Long‐term biodiversity experiments have shown increasing strengths of biodiversity effects on plant productivity over time. However, little is known about rapid evolutionary processes in response to plant community diversity, which could contribute to explaining the strengthening positive relationship. To address this issue, we performed a transplant experiment with offspring of seeds collected from four grass species in a 14‐year‐old biodiversity experiment (Jena Experiment). We used two‐ and six‐species communities and removed the vegetation of the study plots to exclude plant–plant interactions. In a reciprocal design, we transplanted five “home” phytometers (same origin and actual environment), five “away‐same” phytometers (same species richness of origin and actual environment, but different plant composition), and five “away‐different” phytometers (different species richness of origin and actual environment) of the same species in the study plots. In the establishment year, plants transplanted in home soil produced more shoots than plants in away soil indicating that plant populations at low and high diversity developed differently over time depending on their associated soil community and/or conditions. In the second year, offspring of individuals selected at high diversity generally had a higher performance (biomass production and fitness) than offspring of individuals selected at low diversity, regardless of the transplant environment. This suggests that plants at low and high diversity showed rapid evolutionary responses measurable in their phenotype. Our findings provide first empirical evidence that loss of productivity at low diversity is not only caused by changes in abiotic and biotic conditions but also that plants respond to this by a change in their micro‐evolution. Thus, we conclude that eco‐evolutionary feedbacks of plants at low and high diversity are critical to fully understand why the positive influence of diversity on plant productivity is strengthening through time.  相似文献   

17.
Recognizing the imperiled status of biodiversity and its benefit to human well-being, the world''s governments committed in 2010 to take effective and urgent action to halt biodiversity loss through the Convention on Biological Diversity''s “Aichi Targets”. These targets, and many conservation programs, require monitoring to assess progress toward specific goals. However, comprehensive and easily understood information on biodiversity trends at appropriate spatial scales is often not available to the policy makers, managers, and scientists who require it. We surveyed conservation stakeholders in three geographically diverse regions of critical biodiversity concern (the Tropical Andes, the African Great Lakes, and the Greater Mekong) and found high demand for biodiversity indicator information but uneven availability. To begin to address this need, we present a biodiversity “dashboard” – a visualization of biodiversity indicators designed to enable tracking of biodiversity and conservation performance data in a clear, user-friendly format. This builds on previous, more conceptual, indicator work to create an operationalized online interface communicating multiple indicators at multiple spatial scales. We structured this dashboard around the Pressure-State-Response-Benefit framework, selecting four indicators to measure pressure on biodiversity (deforestation rate), state of species (Red List Index), conservation response (protection of key biodiversity areas), and benefits to human populations (freshwater provision). Disaggregating global data, we present dashboard maps and graphics for the three regions surveyed and their component countries. These visualizations provide charts showing regional and national trends and lay the foundation for a web-enabled, interactive biodiversity indicators dashboard. This new tool can help track progress toward the Aichi Targets, support national monitoring and reporting, and inform outcome-based policy-making for the protection of natural resources.  相似文献   

18.
The effect of spring temperature on spring phenology is well understood in a wide range of taxa. However, studies on how winter conditions may affect spring phenology are underrepresented. Previous work on Anthocharis cardamines (orange tip butterfly) has shown population‐specific reaction norms of spring development in relation to spring temperature and a speeding up of post‐winter development with longer winter durations. In this experiment, we examined the effects of a greater and ecologically relevant range of winter durations on post‐winter pupal development of A. cardamines of two populations from the United Kingdom and two from Sweden. By analyzing pupal weight loss and metabolic rate, we were able to separate the overall post‐winter pupal development into diapause duration and post‐diapause development. We found differences in the duration of cold needed to break diapause among populations, with the southern UK population requiring a shorter duration than the other populations. We also found that the overall post‐winter pupal development time, following removal from winter cold, was negatively related to cold duration, through a combined effect of cold duration on diapause duration and on post‐diapause development time. Longer cold durations also lead to higher population synchrony in hatching. For current winter durations in the field, the A. cardamines population of southern UK could have a reduced development rate and lower synchrony in emergence because of short winters. With future climate change, this might become an issue also for other populations. Differences in winter conditions in the field among these four populations are large enough to have driven local adaptation of characteristics controlling spring phenology in response to winter duration. The observed phenology of these populations depends on a combination of winter and spring temperatures; thus, both must be taken into account for accurate predictions of phenology.  相似文献   

19.
Primaquine (PQ) and Tafenoquine (TQ) are clinically important 8‐aminoquinolines (8‐AQ) used for radical cure treatment of Pvivax infection, known to target hepatic hypnozoites. 8‐AQs can trigger haemolytic anaemia in individuals with glucose‐6‐phosphate dehydrogenase deficiency (G6PDd), yet the mechanisms of haemolytic toxicity remain unknown. To address this issue, we used a humanized mouse model known to predict haemolytic toxicity responses in G6PDd human red blood cells (huRBCs). To evaluate the markers of eryptosis, huRBCs were isolated from mice 24–48 h post‐treatment and analysed for effects on phosphatidylserine (PS), intracellular reactive oxygen species (ROS) and autofluorescence. Urinalysis was performed to evaluate the occurrence of intravascular and extravascular haemolysis. Spleen and liver tissue harvested at 24 h and 5–7 days post‐treatment were stained for the presence of CD169+ macrophages, F4/80+ macrophages, Ter119+ mouse RBCs, glycophorin A+ huRBCs and murine reticulocytes (muRetics). G6PDd‐huRBCs from PQ/TQ treated mice showed increased markers for eryptosis as early as 24 h post‐treatment. This coincided with an early rise in levels of muRetics. Urinalysis revealed concurrent intravascular and extravascular haemolysis in response to PQ/TQ. Splenic CD169+ macrophages, present in all groups at day 1 post‐dosing were eliminated by days 5–7 in PQ/TQ treated mice only, while liver F4/80 macrophages and iron deposits increased. Collectively, our data suggest 8‐AQ treated G6PDd‐huRBCs have early physiological responses to treatment, including increased markers for eryptosis indicative of oxidative stress, resulting in extramedullary haematopoiesis and loss of splenic CD169+ macrophages, prompting the liver to act as the primary site of clearance.  相似文献   

20.
Wolinsky H 《EMBO reports》2011,12(12):1226-1229
Looking back on the International Year of Biodiversity, some conservationists hope that it has raised awareness, if nothing else. Even so, many scientists remain pessimistic about our efforts to halt biodiversity decline.The United Nations'' (UN) International Year of Biodiversity in 2010 was supposed to see the adoption of measures that would slow global environmental decline and the continuing loss of endangered species and habitats. Even before, in 2002, most UN members had committed to halting the decline in biodiversity, which is a measure of the health of ecosystems. But the results of these international efforts have been funereal. Moreover, the current global economic crisis, coupled with growing anti-science attitudes in the USA, are adding to the concern of scientists about whether there is the political will to address the loss of biodiversity and whether habitat loss and extinction rates are reaching a point of no return.“There is not a single report received last year that claimed to have stopped or reduced the loss of biodiversity”Ahmed Djoghlaf, Executive Secretary of the Convention on Biological Diversity under the UN Environment Programme based in Montreal, Canada, said that of the 175 national reports submitted as part of the International Year of Biodiversity to his agency last year, none reported any progress. “There is not a single report received last year that claimed to have stopped or reduced the loss of biodiversity,” he said. “These reports confirm that the rate of loss of biodiversity today is unprecedented and the rate is 1,000 higher than the rate of natural extinction on species, and [his agency''s Global Biodiversity Outlook 2010; UN, 2010a] predicts that if business is allowed to continue then major ecosystems, the ocean, the fish, the forests, will reach the tipping point, meaning that there will be irreversible and irreparable damage done to the ecosystems.”The UN campaign traces its roots to the European Union (EU) commitment in 2001 to halt the loss of biodiversity by 2010. The 2010 goal was incorporated into the UN Millennium Development Goals because of the severe impact of biodiversity loss on human well-being. However, the EU last year conceded in a report that it missed its 2010 target, too. The EU''s Biodiversity Action Plan, launched in 2006, shows that Europe''s biodiversity “remains under severe threat from the excessive demands we are making on our environment, such as changes in land use, pollution, invasive species and climate change.” Yet, EU Environment Commissioner Janez Potočnik has seen some positive signs: “We have learned some very important lessons and managed to raise biodiversity to the top of the political agenda. But we need everyone on board and not just in Europe. The threat around the world is even greater than in the EU,” he wrote last year (EC, 2010).Despite the initiative''s poor report card, Djoghlaf was upbeat about the International Year of Biodiversity. “It was a success because it was celebrated everywhere,” he said. “In Switzerland, they conducted a survey before and after the International Year of Biodiversity and they concluded that at the end of the year, 67% of all the Swiss people are now aware of biodiversity. When the year started it was 40%. People are more and more aware. In addition, biodiversity has entered the top of the political agenda.”In October 2010, delegates from 193 countries attended the UN Convention on Biodiversity in Nagoya, Japan, and adopted 20 strategic goals to be achieved by 2020 (UN, 2010b). The so-called Aichi Biodiversity Targets include increased public awareness of the values of biodiversity and the steps that individuals can take to conserve and act sustainably; the halving or halting of the rate of loss of all natural habitats, including forests; and the conservation of 17% of terrestrial and inland water, and 10% of coastal and marine areas through effective and equitable management, resulting in ecologically representative and well-connected systems. By contrast, 13% of land areas and 1% of marine areas were protected in 2010.However, the Convention on Biological Diversity is not enforceable. Anne Larigauderie, Executive Director of DIVERSITAS (Paris, France), which promotes research on biodiversity science, said that it is up to the individual countries to adopt enforceable legislation. “In principle, countries have committed. Now it depends on what individual countries are going to do with the agreement,” she said. “I would say that things are generally going in the right direction and it''s too early to tell whether or not it''s going to have an impact in terms of responding and in terms of the biodiversity itself.”Researchers, however, have been disappointed by The International Year of Biodiversity. Conservation biologist Stuart Butchart, of Birdlife International in Cambridge, UK—a partnership of non-governmental environmental organizations and colleagues from other environmental groups—compiled a list of 31 indicators to measure progress towards the 2010 goal of the International Year of Biodiversity. He and his collaborators reported in Science (Butchart et al, 2010) that these indicators, including species population trends, extinction risks and habitat conditions, showed declines with no significant rate reductions. At the same time, indicators of pressure on biodiversity, such as resource consumption, invasive alien species, nitrogen pollution, over-exploitation and climate change impacts showed increases. “Despite some local successes and increasing responses (including extent and biodiversity coverage of protected areas, sustainable forest management, policy responses to invasive alien species and biodiversity-related aid), the rate of biodiversity loss does not appear to be slowing,” the researchers wrote.wrote.Open in a separate window© Thomas Kitchin & Victoria Hurst/Wave/CorbisButchart pointed out that even if the International Year of Biodiversity had an impact on raising awareness and reducing biodiversity loss, detecting the change would take time. He said that the International Year of Biodiversity fell short of increasing awareness in parts of government not dealing with the environment, including ministries of transport, tourism, treasury and finance. It also seems probable that the campaign had little impact on the business sector, which affects development projects with a direct impact on biodiversity. “People can''t even seem to get together on global climate change, which is a whole lot more obvious and right there,” Peter Raven, president emeritus of the Missouri Botanical Gardens in St Louis, USA, explained. “Biodiversity always seems to be a sort of mysterious background thing that isn''t quite there.”“People can''t even seem to get together on global climate change, which is a whole lot more obvious and right there…”Illka Hanski, a professor in the Department of Ecology and Evolutionary Biology at the University of Helsinki in Finland, said that studies such as Butchart''s “indicate that nothing really happened in 2010. Biodiversity decline continued and has been declining over the past 10 years.”Other researchers are more positive, although with reservations. Conservation biologist Thomas Eugene Lovejoy III, Heinz Center Biodiversity Chair and former president of the Center in Washington, DC, USA—a non-partisan, non-profit organization dedicated to advancing sound environmental policy—said that economic trends affect biodiversity and that biodiversity efforts might actually be benefiting from the current global economic crisis. For example, the decline in the housing markets in the USA and Europe has reduced the demand on lumber for new construction and has led to a reduction in deforestation. “Generally speaking, when there is an economic downturn, some of the things that are pressuring biodiversity actually abate somewhat. That''s the good news. The bad news is that the ability to marshal resources to do some things proactively gets harder,” he said.Chris Thomas, a conservation biologist at the University of York in the UK, who studies ecosystems and species in the context of climate change, said that economic depressions do slow the rate of damage to the environment. “But it also takes eyes off the ball of environmental issues. It''s not clear whether these downturns, when you look over a period of a decade, make much difference or not.” Hanski agreed: “[B]ecause there is less economic activity, there may be less use of resources and such. But I don''t think this is a way to solve our problems. It won''t lead to any stable situation. It just leads to a situation where economic policies become more and more dependent on measures that try actually just to increase the growth as soon as possible.”…biodiversity efforts might actually be benefiting from the current global economic crisisRaven said that in bad times, major interests such as those involved in raising cattle, growing soybeans and clearing habitat for oil palms have reduced political clout because there is less money available for investment. But he said economic downturns do not slow poor people scrounging for sustenance in natural habitats.To overcome this attitude of neglect, Lovejoy thinks there ought to be a new type of ‘economics'' that demonstrates the benefits of biodiversity and brings the “natural world into the normal calculus.” Researchers are already making progress in this direction. Thomas said that the valuation of nature is one of the most active areas of research. “People have very different opinions as to how much of it can be truly valued. But it is a rapidly developing field,” he said. “Once you''ve decided how much something is worth, then you''ve got to ask what are the financial or other mechanisms by which the true value of this resource can be appreciated.”Hanski said that the main problem is the short-term view of economic forecasts. “Rapid use of natural resources because of short-term calculation may actually lead to a sort of exploitation rather than conservation or preservation.” He added that the emphasis on economic growth in rich societies in North America and Europe is frustrating. “We have become much richer than in 1970 when there actually was talk of zero growth in serious terms. So now we are richer and we are becoming more and more dependent on continued growth, the opposite of what we should be aiming at. It''s a problem with our society and economics clearly, but I can''t be very optimistic about the biodiversity or other environmental issues in this kind of situation.” He added that biodiversity is still taking a backseat to economics: “There is a very long way to go right now with the economic situation in Europe, it''s clear that these sorts of [biodiversity] issues are not the ones which are currently being debated by the heads of states.”The economic downturn, which has led to reduced government and private funding and declines in endowments, has also hurt organizations dedicated to preserving biodiversity. Butchart said that some of the main US conservation organizations, including the Nature Conservancy and the World Wildlife Federation, have experienced staff cuts up to 30%. “Organizations have had to tighten their belts and reign in programmes just to stay afloat, so it''s definitely impacted the degree to which we could work effectively,” he said. “Most of the big international conservation organizations have had to lay off large numbers of staff.”…a new type of ‘economics'' that demonstrates the benefits of biodiversity and brings the “natural world into the normal calculus”Cary Fowler, Executive Director of the Global Crop Diversity Trust in Rome, Italy, a public–private partnership to fund key crop collections for food security, also feels the extra challenges of the global economic crisis. “We invest our money conservatively like a foundation would in order to generate income that can reliably pay the bills in these seed banks year after year. So I''m always nervous and I have the computer on at the moment looking at what''s happening with the sovereign debt crisis here in Europe. It''s not good,” he said. “Governments are not being very generous with contributions to this area. Donors will rarely give a reason [for cutting funding].”The political situation in the USA, the world''s largest economy, is also not boding well for conservation of and research into biodiversity. The political extremism of the Republican Party during the run up to the 2012 presidential election has worried many involved in biodiversity issues. Republican contender Texas Governor Rick Perry has been described as ‘anti-science'' for his denial of man-made climate change, a switch from the position of 2008 Republican candidate John McCain. Perry was also reported to describe evolution as a “theory that''s out there, and it''s got some gaps in it” at a campaign event in New Hampshire earlier in the year.“Most of the big international conservation organizations have had to lay off large numbers of staff”Raven said this attitude is putting the USA at a disadvantage. “It drives us to an anti-intellectualism and a lack of real verification for anything which is really serious in terms of our general level of scientific education and our ability to act intelligently,” he said.Still, Larigauderie said that although the USA has not signed the conventions on biodiversity, she has seen US observers attend the meetings, especially under the Obama administration. “They just can''t speak,” she said. Meanwhile, Lovejoy said that biodiversity could get lost in the “unbelievable polarisation affecting US politics. I have worked out of Washington for 36 years now—I''ve never seen anything like this: an unwillingness to actually listen to the other side.”Raven said it is vital for the USA to commit to preserving biodiversity nationally and internationally. “It''s extremely important because our progress towards sustainability for the future will depend on our ability to handle biodiversity in large part. We''re already using about half of all the total photosynthetic productivity on land worldwide and that in turn means we''re cutting our options back badly. The US is syphoning money by selling debt and of course promoting instability all over the world,” he explained. “It''s clear that there is no solution to it other than a level population, more moderate consumption levels and new technologies altogether.”The EU and the UN have also changed the time horizon for halting the decline in biodiversity. As part of the Nagoya meeting, the UN announced the UN Decade for Biodiversity. The strategic objectives include a supporting framework for the implementation of the Biodiversity Strategic Plan 2011–2020 and the Aichi Biodiversity Targets, as well as guidance to regional and international organizations, and more public awareness of biodiversity issues.But Butchart remains sceptical. “I suspect ‘decades of whatever'' have even less impact than years,” he said. “2008 was the International Year of the Potato. I don''t know how much impact that had on your life and awareness. I think there is greater awareness and greater potential to make significant progress in addressing biodiversity loss now than there was 10 years ago, but the scale of the challenge is still immense.”“…our progress towards sustainability for the future will depend on our ability to handle biodiversity in large part”Hanski has similar doubts. “I believe it''s inevitable that a very large fraction of the species on Earth will go extinct in the next hundred years. I can''t see any change to that.” But he is optimistic that some positive change can be made. “Being pessimistic doesn''t help. The nations still can make a difference.” He said he has observed ecotourism playing a role in saving some species in Madagascar, where he does some of his research.“We''re not going to fundamentally be able to wipe life off the planet,” Thomas said. “We will wipe ourselves off the planet virtually certainly before we wipe life out on Earth. However, from the point of view of humanity as a culture, and in terms of the resources we might be able to get from biodiversity indirectly or directly, if we start losing things then it takes things millions of years to ‘re-evolve'' something that does an equivalent job. From a human perspective, when we wipe lots of things out, they''re effectively permanently lost. Of course it would be fascinating and I would love to be able to come back to the planet in 10 million years and see what it looks like, assuming humans are not here and other stuff will be.”Djoghlaf, by contrast, is more optimistic about our chances: “I believe in the human survival aspect. When humankind realises that the current pattern of production and consumption and the current way that it is dealing with nature is unsustainable, we will wake up.”  相似文献   

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