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1.
Front Plant Sci ; 15: 1253260, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39109066

RESUMEN

Seasonally tropical dry forests (SDTFs) in the American tropics are a highly diverse yet poorly understood and endangered ecosystem scattered from Northern Mexico to Southern Argentina. One floristic element of the STDFs is the genus Magoniella (Polygonaceae), which includes two liana species, M. laurifolia and M. obidensis, which have winged fruits and are distributed from Costa Rica to Southern Brazil. In a field expedition to the SDTFs of the Colombian Caribbean in 2015, morphologically distinctive individuals of Magoniella were found. In this study, we investigated the species boundaries within Magoniella and determined the phylogenetic position of these morphologically distinctive individuals in the tribe Triplaridae. We compiled morphological trait data across 19 specimens of both species and produced newly sequenced nuclear-plastid DNA data for M. obidensis. Morphometric analyses revealed significant differences in fruit length and perianth size among individuals from the Colombian Caribbean compared to M. obidensis and bract length when compared to M. laurifolia. Maximum likelihood analysis of non-conflicting nuclear and plastid datasets placed the Colombian Caribbean individuals as sister to M. obidensis with maximum statistical support. Additionally, pairwise sequence comparisons of the nuclear ribosomal ITS and the lfy2i loci consistently showed 15-point mutations (10 transitions, five transversions) and six 2 bp-long substitutions that differ between M. obidensis and the Colombian Caribbean individuals. Our morphological and molecular evidence thus suggests that the Colombian Caribbean individuals of Magoniella represent a divergent population from M. laurifolia and M. obidensis, which we describe and illustrate as a new species, M. chersina. Additionally, we provide nomenclatural updates for M. laurifolia and M. obidensis. This study highlights the power of combining morphological and molecular evidence in documenting and naming plant diversity.

2.
Glob Chang Biol ; 30(3): e17208, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38441414

RESUMEN

Substantial global restoration commitments are occurring alongside a rapid expansion in land-hungry tropical commodities, including to supply increasing demand for wood products. Future commercial tree plantations may deliver high timber yields, shrinking the footprint of production forestry, but there is an as-yet unquantified risk that plantations may expand into priority restoration areas, with marked environmental costs. Focusing on Brazil-a country of exceptional restoration importance and one of the largest tropical timber producers-we use random forest models and information on the economic, social, and spatial drivers of historic commercial tree plantation expansion to estimate and map the probability of future monoculture tree plantation expansion between 2020 and 2030. We then evaluate potential plantation-restoration conflicts and opportunities at national and biome-scales and under different future production and restoration pathways. Our simulations show that of 2.8 Mha of future plantation expansion (equivalent to plantation expansion 2010-2020), ~78,000 ha (3%) is forecast to occur in the top 1% of restoration priority areas for terrestrial vertebrates, with ~547,500 ha (20%) and ~1,300,000 ha (46%) in the top 10% and 30% of priority areas, respectively. Just ~459,000 ha (16%) of expansion is forecast within low-restoration areas (bottom 30% restoration priorities), and the first 1 Mha of plantation expansion is likely to have disproportionate impacts, with potential restoration-plantation overlap starkest in the Atlantic Forest but prominent in the Pampas and Cerrado as well. Our findings suggest that robust, coherent land-use policies must be deployed to ensure that significant trade-offs between restoration and production objectives are navigated, and that commodity expansion does not undermine the most tractable conservation gains under emerging global restoration agendas. They also highlight the potentially significant role an engaged forestry sector could play in improving biodiversity outcomes in restoration projects in Brazil, and presumably elsewhere.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Brasil , Agricultura Forestal , Probabilidad
3.
BMC Biol ; 21(1): 26, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36750946

RESUMEN

BACKGROUND: Ponerine ants are almost exclusively predatory and comprise many of the largest known ant species. Within this clade, the genus Neoponera is among the most conspicuous Neotropical predators. We describe the first fossil member of this lineage: a worker preserved in Miocene-age Dominican amber from Hispaniola. RESULTS: Neoponera vejestoria sp. nov. demonstrates a clear case of local extinction-there are no known extant Neoponera species in the Greater Antilles. The species is attributable to an extant and well-defined species group in the genus, which suggests the group is older than previously estimated. Through CT scan reconstruction and linear morphometrics, we reconstruct the morphospace of extant and fossil ants to evaluate the history and evolution of predatory taxa in this island system. CONCLUSIONS: The fossil attests to a shift in insular ecological community structure since the Miocene. The largest predatory taxa have undergone extinction on the island, but their extant relatives persist throughout the Neotropics. Neoponera vejestoria sp. nov. is larger than all other predatory ant workers known from Hispaniola, extant or extinct. Our results empirically demonstrate the loss of a functional niche associated with body size, which is a trait long hypothesized to be related to extinction risk.


Asunto(s)
Hormigas , Animales , Fósiles , Ámbar , República Dominicana , Tamaño Corporal
4.
Proc Biol Sci ; 289(1984): 20220887, 2022 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-36476005

RESUMEN

Many tropical seed-dispersing frugivores are facing extinction, but the consequences of the loss of endangered frugivores for seed dispersal is not well understood. We investigated the role of frugivore endangerment status via robustness-to-coextinction simulations (in this context, more accurately described as robustness-to-partner-loss simulations) using data from the Brazilian Atlantic Forest biodiversity hotspot. By simulating the extinction of endangered frugivores, we found a rapid and disproportionate loss of tree species with dispersal partners in the network, and this surprisingly surpassed any other frugivore extinction scenario, including the loss of the most generalist frugivores first. A key driver of this pattern is that many specialist plants rely on at-risk frugivores as seed-dispersal partners. Moreover, interaction compensation in the absence of endangered frugivores may be unlikely because frugivores with growing populations forage on fewer plant species than frugivores with declining populations. Therefore, protecting endangered frugivores could be critical for maintaining tropical forest seed dispersal, and their loss may have higher-than-expected functional consequences for tropical forests, their regeneration processes, and the maintenance of tropical plant diversity.


Asunto(s)
Dispersión de Semillas , Brasil
5.
Biota Neotrop. (Online, Ed. ingl.) ; 22(spe): e20221363, 2022. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1394009

RESUMEN

Abstract Mammals are charismatic organisms that play a fundamental role in ecological functions and ecosystem services, such as pollination, seed dispersal, nutrient cycling, and pest control. The state of São Paulo represents only 3% of the Brazilian territory but holds 33% of its mammalian diversity. Most of its territory is dominated by agriculture, pastures, and urban areas which directly affect the diversity and persistence of mammals in the landscape. In addition, São Paulo has the largest port in Latin America and the largest offshore oil reservoir in Brazil, with a 600 km stretch of coastline with several marine mammal species. These human-made infrastructures affect the diversity, distribution, ecology, and the future of mammals in the state. Here, we answer five main questions: 1) What is the diversity of wild mammals in São Paulo state? 2) Where are they? 3) What is their positive and negative impact on human well-being? 4) How do mammals thrive in human-modified landscapes? 5) What is the future of mammals in the state? The state of São Paulo holds 255 species of native mammals, with four endemic species, two of them globally endangered. At least six species (two marsupials, Giant otter, Pampas deer, Brazilian dwarf brocket deer, and Giant armadillo) were extirpated from the state due to hunting and habitat loss. The intense human land use in the state forced many mammalian species to change their diet to cope with the intense fragmentation and agriculture. Large-scale monoculture has facilitated the invasion of exotic species such as wild boars (javali) and the European hare. Several "savanna-dwelling" species are expanding their ranges (Maned wolf, Brocket deer) over deforested areas and probably reflect changes towards a drier climate. Because the state has the largest road system, about 40,000 mammals from 33 species are killed per year in collisions causing an economic loss of 12 million dollars/year. The diversity of mammals is concentrated in the largest forest remnants of Serra do Mar and in the interior of the State, mainly in the regions of Ribeirão Preto and Jundiaí. Sampling gaps are concentrated throughout the interior of the state, particularly in the northwest region. Wild mammals play a fundamental role in many ecosystem services, but they can also be a concern in bringing new emergent diseases to humans. Although the taxonomy of mammals seems to be well known, we show that new species are continuously being discovered in the state. Therefore, continuous surveys using traditional and new technologies (eDNA, iDNA, drones), long-term population monitoring, investigation of the interface of human-wildlife conflict, and understanding of the unique ecosystem role played by mammals are future avenues for promoting sustainable green landscapes allied to human well-being in the state. The planting of forest or savanna corridors, particularly along with major river systems, in the plateau, controlling illegal hunting in the coastal areas, managing fire regimes in the Cerrado, and mitigating roadkill must be prioritized to protect this outstanding mammal diversity.


Resumo Os mamíferos são organismos carismáticos que desempenham um papel fundamental na função ecológica e nos serviços ecossistêmicos, como polinização, dispersão de sementes, ciclagem de nutrientes e controle de pragas. O Estado de São Paulo representa apenas 3% do território brasileiro, mas detém 33% da diversidade de mamíferos. A maior parte de seu território é dominado pela agricultura, pastagens e áreas urbanas que afetam diretamente a diversidade e a persistência dos mamíferos na paisagem. Além disso, São Paulo possui o maior porto da América Latina e o maior reservatório de petróleo costeiro do Brasil, com 600 km de extensão de litoral com diversas espécies de mamíferos marinhos. Essas infraestruturas afetam a diversidade, distribuição, ecologia e o futuro dos mamíferos no estado. Aqui, respondemos cinco perguntas principais: 1) Qual é a diversidade de mamíferos silvestres no Estado de São Paulo? 2) Onde eles ocorrem? 3) Qual é o seu impacto positivo e negativo no bem-estar humano? 4) Como os mamíferos persistem em paisagens modificadas pelo homem? 5) Qual é o futuro dos mamíferos no estado? O estado de São Paulo possui 255 espécies de mamíferos nativos, com quatro espécies endêmicas, duas delas globalmente ameaçadas de extinção. Pelo menos seis espécies (dois marsupiais, ariranha, veado-campeiro, veado-cambuta e tatu-canastra) foram extirpadas do estado devido à caça e perda de habitat. O intenso uso humano da terra no estado forçou muitas espécies de mamíferos a mudar sua dieta para lidar com a intensa fragmentação e agricultura. A monocultura em larga escala facilitou a invasão de espécies exóticas, como porcos selvagens (javaporco) e a lebre europeia. Várias espécies de áreas abertas estão expandindo suas áreas de distribuição (lobo-guará, veado-catingueiro) sobre áreas desmatadas e provavelmente refletem mudanças em direção a um clima mais seco. Como o estado possui o maior sistema rodoviário do Brasil, cerca de 40 mil mamíferos de 33 espécies são mortos por ano em colisões, causando um prejuízo econômico de 12 milhões de dólares/ano. A diversidade de mamíferos está concentrada nos maiores remanescentes florestais da Serra do Mar e no interior do Estado, principalmente nas regiões de Ribeirão Preto e Jundiaí. As lacunas amostrais estão concentradas em todo o interior do estado, principalmente na região noroeste. Os mamíferos silvestres desempenham um papel fundamental em muitos serviços ecossistêmicos, mas também podem ser uma preocupação em trazer novas doenças emergentes para as populações humanas. Embora a taxonomia de mamíferos pareça ser bem conhecida, mostramos que novas espécies estão sendo continuamente descobertas no estado. Portanto, pesquisas usando tecnologias tradicionais e novas (eDNA, iDNA, drones), monitoramento populacional de longo prazo, a investigação da interface do conflito homem-vida selvagem e a compreensão do papel único no ecossistema desempenhado pelos mamíferos são um caminho futuro para promover uma paisagem verde sustentável aliada ao bem-estar humano no estado. O plantio de corredores florestais ou de cerrado, principalmente junto aos principais sistemas fluviais, no planalto, o controle da caça ilegal nas áreas costeiras, o manejo dos regimes de fogo no Cerrado e a mitigação dos atropelamentos devem ser uma prioridade para proteger essa notável diversidade de mamíferos.

6.
Rev. peru. biol. (Impr.) ; 28(spe): e21967, dic. 2021. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1377185

RESUMEN

Resumen Para tomar decisiones en conservación o manejo de especies silvestres es prioritario conocer su estado de conservación, siendo el método de la IUCN el más utilizado para categorizar especies según su nivel de amenaza, tanto a nivel global como a nivel nacional. En este artículo realizamos un análisis de las especies de plantas y vertebrados amenazadas y de aquellas con datos insuficientes del departamento de Loreto, el más grande y uno de los más biodiversos del Perú, con el fin de identificar las principales amenazas que soportan, identificar los vacíos de información y comparar la congruencia entre la lista nacional y la global. Uniendo ambas listas, en Loreto se ha registrado 226 especies consideradas amenazadas. Existen grandes diferencias entre la lista nacional y la global, principalmente para plantas y peces. La principal amenaza registrada es la pérdida de hábitat, que afecta a la mayor parte de las especies de vertebrados terrestres amenazados. Existen grandes vacíos de información sobre tamaño y tendencia poblacional en todos los grupos taxonómicos, y de distribución en las plantas amenazadas. Entre las especies con datos insuficientes, los vacíos principales se dan en los aspectos de distribución y población, pero también en amenazas, ecología y taxonomía. Nuestros resultados resaltan la necesidad de actualizar la lista de plantas amenazadas del Perú, así como crear una lista de peces amenazados y realizar investigación sobre distribución, población, amenazas y taxonomía de las especies con datos insuficientes y de las especies amenazadas con vacíos de información.


Abstract In order to make decisions on the conservation or management of wild species, it is a priority to know their conservation status. For this purpose, the most widely used method is IUCN's categorization of species according to the level of threat they face, both globally and nationally. In this article we conducted an analysis of threatened plant and vertebrate species, and of data deficient species in the department of Loreto, the largest and one of the most biodiverse in Peru, to identify the main threats they face, identify information gaps, and compare the national and global lists. According to both lists combined, 226 species considered threatened have been recorded in Loreto. Large differences exist between the national and global lists, mainly for plants and fish. The main threat recorded is habitat loss, which affects most of the threatened terrestrial vertebrate species. Large gaps persist in information on population size and trends for all taxonomic groups, and on distribution for threatened plants. Among the data deficient species, the main gaps are in distribution and population aspects, but also in threats, ecology, and taxonomy. Our results highlight the need to update the list of threatened plants of Peru, as well as to create a list of threatened fish species and to conduct research on the distribution, population, threats, and taxonomy of species with deficient data and threatened species with information gaps.

7.
Conserv Biol ; 35(6): 1821-1832, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34166530

RESUMEN

The reintroduction of a species that is extinct in the wild demands caution because reintroduction locations may be associated with threats, such as hunting, poor-quality habitat, and climate change. This is the case for Cyanopsitta spixii (Spix's Macaw), which has been extinct in the wild since 2000. The few living individuals were created in captivity and will be used in a reintroduction project within the species' original distribution area, the Caatinga domain (Brazil). Because the occurrence records for this bird are old and inaccurate, we investigated the current and future environmental suitability of the 14 plant species used by C. spixii as resource. These plants are key elements for the long-term reestablishment of the species in the wild, so the use of models helps in the assessment of the effects of climate change on the availability of these resources for the species and informs selection of the best places for reintroduction. We based our models of environmental suitability on 19 bioclimatic variables and nine physical soil and topography variables. Climate projections were created for the present and for the year 2070 with an optimistic (SSP2-4.5) and a pessimistic (SSP5-8.5) climate scenario. Both future climate scenarios lead to a reduction in area of environmental suitability that overlapped for all the plant species: 33% reduction for SSP2-4.5 and 63% reduction for SSP5-8.5. If our projections materialize, climate change could thus affect the distribution of key resources, and the maintenance of C. spixii would depend on restoration of degraded areas, especially riparian forests, and the preservation of already existing natural areas. The Caatinga domain is very threatened by habitat loss and, for the success of this reintroduction project, the parties involved must act to protect the species and the resources it uses.


Evaluación de los Sitios de Reintroducción de Especies con base en la Futura Idoneidad Climática para los Recursos Alimenticios Resumen La reintroducción de una especie que se encuentra extinta en vida libre exige precaución pues las localidades de reintroducción pueden estar asociadas con amenazas como la cacería, hábitats de mala calidad y el cambio climático. Éste es el caso para Cyanopsitta spixii (Guacamaya de Spix), que ha estado extinta en vida libre desde el 2000. Los pocos individuos vivos nacieron en cautiverio y se usarán para un proyecto de reintroducción dentro del área original de distribución de la especie: el dominio Caatinga (Brasil). Ya que los registros de la presencia de esta ave son viejos e imprecisos, investigamos la idoneidad ambiental actual y a futuro de 14 especies de plantas que C. spixii usa como recurso. Estas plantas son elementos importantes para el restablecimiento a largo plazo de las especies en vida silvestre, así que el uso de modelos asiste en la evaluación de los efectos del cambio climático sobre la disponibilidad de recursos para la especie e informa la selección de los mejores lugares para la reintroducción. Basamos nuestros modelos de la idoneidad ambiental en 19 variables bioclimáticas y 9 variables físicas del suelo y la topografía. Las proyecciones climáticas fueron creadas para el presente y para el año 2070 con un escenario climático optimista (SSP2-4.5) y uno pesimista (SSP5-8.5) Ambos escenarios climáticos futuros llevan a una reducción en el área de idoneidad ambiental sobrepuesta para todas las especies de plantas: 33% de reducción para SSP2-4.5 y 63% de reducción para SSP5-8.5. Si nuestras proyecciones se materializan, el cambio climático podría entonces afectar la distribución de los recursos importantes, por lo que la conservación de C. spixii dependería de la restauración de las áreas degradadas, especialmente los bosques riparios y la preservación de las áreas naturales existentes. El dominio Caatinga se encuentra muy amenazado por la pérdida del hábitat y, para el éxito de este proyecto de reintroducción, las partes involucradas deben actuar para proteger a la especie y los recursos que utiliza.


Asunto(s)
Conservación de los Recursos Naturales , Caza , Cambio Climático , Ecosistema , Bosques , Humanos
8.
Proc Biol Sci ; 288(1946): 20202905, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33715429

RESUMEN

Preventing extinctions requires understanding macroecological patterns of vulnerability or persistence. However, correlates of risk can be nonlinear, within-species risk varies geographically, and current-day threats cannot reveal drivers of past losses. We investigated factors that regulated survival or extinction in Caribbean mammals, which have experienced the globally highest level of human-caused postglacial mammalian extinctions, and included all extinct and extant Holocene island populations of non-volant species (219 survivals or extinctions across 118 islands). Extinction selectivity shows a statistically detectable and complex body mass effect, with survival probability decreasing for both mass extremes, indicating that intermediate-sized species have been more resilient. A strong interaction between mass and age of first human arrival provides quantitative evidence of larger mammals going extinct on the earliest islands colonized, revealing an extinction filter caused by past human activities. Survival probability increases on islands with lower mean elevation (mostly small cays acting as offshore refugia) and decreases with more frequent hurricanes, highlighting the risk of extreme weather events and rising sea levels to surviving species on low-lying cays. These findings demonstrate the interplay between intrinsic biology, regional ecology and specific local threats, providing insights for understanding drivers of biodiversity loss across island systems and fragmented habitats worldwide.


Asunto(s)
Extinción Biológica , Mamíferos , Animales , Región del Caribe , Humanos , Islas , Indias Occidentales
9.
Biota Neotrop. (Online, Ed. ingl.) ; 21(2): e20201083, 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1285463

RESUMEN

Abstract: Knowledge of the ichthyofauna of a hydrographic basin is the minimum necessary condition for the implementation of any measures for the exploration, management or preservation of water and fishing resources. Despite its relevance, the number of fish species across the Iguassu River basin is still uncertain. Thus, the objective of this study was to compile the fish species that occur in the extensive stretch of the basin above the Iguassu Falls. In addition, we recorded the level of threat of extinction for native species, the origin of nonnative species, and their main vectors of introduction. To achieve this goal, a survey was carried out through consultations with ichthyological collections as well as online databases. Also, a literature review was conducted using the search platforms Thomson Reuters, SciELO and Elsevier's ScienceDirect to locate all articles published by March 2020 that addressed the topic "ichthyofauna in the Iguassu River basin". The survey compiled a total of 133 fish species distributed in nine orders, 29 families and 72 genera. Seventy-nine fish species were recorded that occur throughout the entire length of the basin, 119 species that occur in the hydrographic units of the middle and lower Iguassu River (40 exclusive) and 93 species that occur in the hydrographic unit of the upper Iguassu River (14 exclusive). The endemism rate shown here for the Iguassu River basin (approximately 69%) contrasts with the 40 nonnative fish species recorded (approximately 30% of the total species in the basin). Successive impoundments, reductions in habitat quality and the increase in the number of nonnative species are the main threats to native species, especially to the endemic species; approximately 20% of these species were listed in some category of threat of extinction. We emphasize that constant monitoring of ichthyofauna is necessary to discover putatively undescribed species, as well as for the application of management strategies to mitigate the negative effects and promote the control of the spread of nonnative species.


Resumo: Conhecer a ictiofauna de uma bacia hidrográfica compreende condição mínima necessária para que se possam implantar quaisquer medidas de exploração, manejo ou preservação dos recursos hídricos e pesqueiros. Apesar de sua relevância, o número de espécies de peixes de toda a bacia hidrográfica do rio Iguaçu ainda é incerto. Assim, o objetivo deste estudo foi compilar as espécies de peixes que ocorrem no extenso trecho da bacia acima das Cataratas do Iguaçu. Além disso, registramos o nível de ameaça de extinção às espécies nativas, a origem das espécies não nativas e suas principais vias de introdução. Para isso foi realizado um levantamento por meio de consultas a coleções ictiológicas, bem como aos bancos de dados online, além de revisão de literatura por meio do uso das plataformas de buscas Thomson Reuters, Scielo e Elsevier - ScienceDirect, que abordavam o tópico "ictiofauna da bacia do rio Iguaçu" e o período de tempo incluiu todos os trabalhos publicados até março de 2020. O levantamento compilou ao todo 133 espécies, distribuídas em nove ordens, 29 famílias e 72 gêneros. Em toda a extensão da bacia foram registradas 79 espécies de peixes. Nas unidades hidrográficas do médio e baixo rio Iguaçu foram registradas 119 espécies (40 exclusivas) e na unidade hidrográfica do alto rio Iguaçu foram registradas 93 espécies (14 exclusivas). A taxa de endemismo para a bacia do rio Iguaçu (aproximadamente 69%) contrasta com as 40 espécies de peixes não nativos registradas (aproximadamente 30% do total de espécies na bacia). Os sucessivos barramentos, a perda de qualidade de habitats e o aumento no número de espécies não nativas são ameaças às espécies autóctones, especialmente às endêmicas, as quais apresentam aproximadamente 20% listadas em alguma categoria de ameaça ao risco de extinção. Ressaltamos que o monitoramento constante da ictiofauna é necessário para a descoberta de espécies supostamente não descritas, bem como para a aplicação de estratégias de manejo para mitigar os efeitos negativos e promover o controle da disseminação de espécies não nativas.

10.
Biota Neotrop. (Online, Ed. ingl.) ; 21(3): e20211204, 2021. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1278412

RESUMEN

Abstract: Climate change will likely be the most significant challenge faced by species in this century, and species' ability to cope with climate change depends on their life history and ecological and evolutionary traits. Understanding how these traits mediate species' responses is beneficial for identifying more vulnerable species or prone to extinction risk. Here, we carried out a literature review describing how four traits commonly used in vulnerability assessments (i.e. clutch size, diet breadth, dispersal ability, and climatic tolerance) may determine species vulnerability. We also portray the possible mechanisms that explain how these traits govern species responses to climate change. The literature suggests different mechanisms operating for the evaluated traits. The mechanism of response to climate change differs between species inhabiting tropical and temperate regions: while species from the temperate areas may respond positively to temperature rise, tropical species may be severely affected. Since ectotherms depend on environment temperature, they are more sensitive and present different response mechanisms from endotherms.


Resumo: A mudança climática provavelmente será o maior desafio enfrentado pelas espécies neste século e a capacidade das espécies em lidar com a mudança climática depende de seus próprios atributos de história de vida, ecológicos e evolutivos. Entender como esses atributos mediam as respostas das espécies é extremamente útil para identificar espécies que são mais vulneráveis ou sujeitas ao risco de extinção. Aqui, realizamos uma revisão da literatura com foco na descrição de como quatro atributos comumente usados em avaliações de vulnerabilidade (tamanho da ninhada, amplitude da dieta, capacidade de dispersão e tolerância climática) podem realmente determinar a vulnerabilidade das espécies. Também retratamos os possíveis mecanismos que explicam como esses atributos governam as respostas das espécies à mudança climática. A literatura sugere diferentes mecanismos operando para os atributos avaliados. O mecanismo de resposta à mudança climática difere entre as espécies que habitam as regiões tropicais e temperadas: enquanto as espécies das regiões temperadas podem responder positivamente ao aumento da temperatura, as espécies tropicais podem ser severamente afetadas. Como os ectotérmicos dependem da temperatura ambiente, eles são mais sensíveis e apresentam mecanismos de resposta diferentes dos endotérmicos.

11.
Integr Environ Assess Manag ; 16(5): 676-680, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32176418

RESUMEN

The Fundão tailings dam held back approximately 50 million cubic meters of tailings from an Fe ore mine in the state of Minas Gerais, Brazil. The dam failed on 5 November 2015, releasing tailings into the Rio Doce watershed and causing an environmental disaster in a biodiversity hotspot. To guide conservation action following the event, Brazilian authorities demanded an impact assessment focused on terrestrial species threatened by extinction. Postdisaster impact assessment is substantially more challenging than predevelopment impact assessment. Predisaster baseline data were sparse, and much was unknown about how the Fundão dam failure impacted terrestrial species threatened with extinction. Baseline reconstruction and impact pathway validation and characterization was critical. Ecosystem reconstruction revealed that 1580 ha of terrestrial ecosystems were destroyed, including approximately 480 ha of Atlantic rainforest. Collaboration with local experts identified 346 species of vertebrates, invertebrates, and vascular plants threatened with extinction that were impacted or potentially impacted. Species composition and impacts varied within 4 distinct segments of the Rio Doce watershed. Nine potential impact pathways were identified using data and literature review combined with information provided by regulators, experts, and media. Not all were valid. Validating and characterizing each pathway within each watershed segment involved data evaluation, an ecological risk screening, and field assessments. Impact pathway evaluation proved critical to dispelling misconception, accurately understanding postdisaster impacts, and directing conservation action; the importance of this step cannot be overemphasized. Integr Environ Assess Manag 2020;16:676-680. © 2020 SETAC.


A barragem de Fundão armazenava milhões de metros cúbicos de rejeitos de uma mina de ferro no estado de Minas Gerais, Brasil. A barragem se rompeu em 5 de novembro de 2015, liberando rejeitos para a bacia do rio Doce, provocando um desastre ambiental em um hotspot de biodiversidade. Visando orientar ações de conservação após o evento, autoridades ambientais brasileiras demandaram uma avaliação de impactos com foco em espécies ameaçadas de extinção. Avaliações de impacto pós-desastre são substancialmente mais desafiadoras do que avaliações padrão, que antecedem a execução de empreendimentos. No caso de Fundão, dados da linha de base anterior ao desastre eram escassos, e pouco se sabia a respeito de como os vetores de impacto relacionados ao rompimento poderiam ter afetado a biodiversidade terrestre, incluindo a sua magnitude, duração e abrangência espacial. Consequentemente, a reconstrução da linha de base e a validação e caracterização dos potenciais vetores de impacto foram os primeiros passos essenciais. A reconstrução da linha de base para ecossistemas, feita a partir de imagens de satélite, revelou que aproximadamente 1580 ha de ecossistemas terrestres foram suprimidos, incluindo ~480 ha de mata atlântica. Por meio de colaboração com especialistas na biodiversidade local e utilizando fontes diversas de dados e literatura, foram identificadas 346 espécies de vertebrados, invertebrados e plantas vasculares ameaçadas de extinção ocorrentes ou potencialmente ocorrentes nas áreas afetadas. A composição em espécies variou entre quatro distintos segmentos da bacia do rio Doce, assim como os impactos incidentes. Nove potenciais vetores de impacto foram identificados utilizando-se dados e revisões da literatura, além de informações fornecidas por órgãos ambientais e especialistas, e pela mídia. A validação e caracterização de cada vetor de impacto em cada segmento da bacia envolveu a avaliação de dados, uma análise preliminar de risco ecológico, e avaliações em campo. A avaliação de vetores de impacto mostrou-se fundamental para dirimir equívocos de interpretação e acuradamente entender os impactos pós-desastre; a importância desta etapa não pode ser menosprezada. O cruzamento de características biológicas e ecológicas das espécies terrestres ameaçadas de extinção, em cada segmento da bacia, com a caracterização dos vetores de impacto, permitiu a atribuição de consequências dos impactos, constituindo uma maneira efetiva de priorizar medidas mitigadoras com vistas ao alcance de metas de conservação pós-desastre. Integr Environ Assess Manag 2020;16:676-680.


Asunto(s)
Desastres , Ríos , Colapso de la Estructura , Animales , Brasil , Ecosistema
12.
Neotrop Entomol ; 49(2): 213-226, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31916201

RESUMEN

Ground beetles (Coleoptera: Carabidae) are among the early colonisers of recently deglaciated terrains. While patterns of carabid colonisation along forelands of retreating glaciers have been thoroughly investigated in temperate climates, information remains scarce in tropical mountains. This study aimed to describe for the first time the carabid beetle species assemblages along the chronosequence of two tropical Andean glaciers (Antisana and Carihuairazo, Ecuador). Shannon index, taxonomic distinctness and species assemblage composition did not reveal deterministic and directional patterns. Only the principal coordinate analysis performed on the Antisana dataset showed that some species had a clear preference for terrains deglaciated for more than 200 years. Our results showed that equatorial glacier forelands are colonised by pioneer species that persist from the recently deglaciated terrains (less than 25 years) to terrains deglaciated since more than 200 years. This pattern fits the 'addition and persistence model' of high-latitude glacier forelands, rather than the 'species replacement model' of the Alps. The pioneer species observed are high-altitude specialists adapted to constantly cold environments, but not specifically ice-related. In the current context of climate warming, pioneer and cold-adapted species living near the glaciers of equatorial mountains are therefore only threatened by the 'summit trap' risk, unlike in temperate regions, as they are not strictly linked to the glacier microclimate.


Asunto(s)
Distribución Animal , Escarabajos/clasificación , Cubierta de Hielo , Animales , Clima , Ecuador
13.
Conserv Biol ; 34(1): 266-275, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31183898

RESUMEN

As a landscape becomes increasingly fragmented through habitat loss, the individual patches become smaller and more isolated and thus less likely to sustain a local population. Metapopulation theory is appropriate for analyzing fragmented landscapes because it combines empirical landscape features with species-specific information to produce direct information on population extinction risks. This approach contrasts with descriptions of habitat fragments, which provide only indirect information on risk. Combining a spatially explicit metapopulation model with empirical data on endemic species' ranges and maps of habitat cover, we calculated the metapopulation capacity-a measure of a landscape's ability to sustain a metapopulation. Mangroves provide an ideal model landscape because they are of conservation concern and their patch boundaries are easily delineated. For 2000-20015, we calculated global metapopulation capacity for 99 metapopulations of 32 different bird species endemic to mangroves. Northern Australia and Southeast Asia had the highest richness of mangrove endemic birds. The Caribbean, Pacific coast of Central America, Madagascar, Borneo, and isolated patches in Southeast Asia in Myanmar and Malaysia had the highest metapopulation losses. Regions with the highest loss of habitat area were not necessarily those with the highest loss of metapopulation capacity. Often, it was not a matter of how much, but how the habitat was lost. Our method can be used by managers to evaluate and prioritize a landscape for metapopulation persistence.


Uso de la Teoría de Metapoblaciones para la Conservación Práctica de las Aves Endémicas de Manglares Resumen A medida que un paisaje se fragmenta cada vez más debido a la pérdida de hábitat, los parches se vuelven más pequeños y aislados y, por lo tanto, menos propensos a sostener a una población local. La teoría de metapoblaciones es adecuada para analizar paisajes fragmentados porque combina características empíricas del paisaje con información de cada especie para producir información directa sobre los riesgos de extinción de la población. Este enfoque contrasta con las descripciones de los fragmentos de hábitat que solo proporcionan información directa sobre el riesgo. Mediante la combinación de un modelo metapoblacional espacialmente explícito con datos empíricos de los rangos de distribución de especies endémicas y mapas de la cobertura del hábitat, calculamos la capacidad de la metapoblación - una medida de la capacidad del paisaje para sostener una metapoblación. Los manglares proporcionan un paisaje modelo ideal porque son de interés para la conservación y los límites de los parches son delineados fácilmente. Calculamos la capacidad de la metapoblación global para el período 2000-2015 de 99 metapoblaciones de 32 especies de aves endémicas de manglares. El norte de Australia y el sudeste de Asia tuvieron la mayor riqueza de aves endémicas de manglares. El Caribe, la costa del Pacífico de Centroamérica, Madagascar, Borneo y parches aislados en el sudeste de Asia en Myanmar y Malasia tuvieron las mayores pérdidas de metapoblaciones. Las regiones con mayor pérdida hábitat fueron necesariamente aquellas con mayor pérdida de capacidad de la metapoblación. A menudo no era una cuestión de cuánto, sino cómo se perdió el hábitat. Nuestro método se puede utilizar por manejadores para evaluar y priorizar un paisaje para la persistencia de la metapoblación.


Asunto(s)
Conservación de los Recursos Naturales , Modelos Biológicos , Animales , Australia , Aves , Borneo , Región del Caribe , América Central , Ecosistema , Madagascar , Malasia , Mianmar , Dinámica Poblacional
14.
J Theor Biol ; 485: 110051, 2020 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-31626812

RESUMEN

In community ecology, neutral models make the assumption that species are equivalent, such that species abundances differ only because of demographic stochasticity. Despite their ecological simplicity, neutral models have been found to give reasonable descriptions of expected patterns of biodiversity in communities with many species. Such patterns include the expected total number of species and species-abundance distributions describing the expected number of species in different abundance classes. However, the expected patterns represent only the central tendencies of the full distributions of possible outcomes. Thus, ecological inferences and conclusions based only on expected patterns are incomplete, and may be misleading. Here, we address this issue for the spatially implicit neutral model, by using classic results from birth-death processes to derive (1) the probability distribution of extinction time of a species with given abundance for the metacommunity; (2) the probability distributions of total species richness and number of species with given abundance for both the metacommunity and local community; and (3) the probability distributions of the average immigration and extinction rates in the local community, across different values of total species richness. We illustrate the utility of these probability distributions in providing greater ecological insight via statistical inference. Firstly, we show that under the neutral metacommunity model, there is only 2.65×10-9 probability that the age of a common tree species in the Amazon is  ≤ 3  × 108 yr, which is approximately the oldest estimated age of the first angiosperm. Thus, species ages from the model are unrealistically high. Secondly, for a tree community in a 50 ha plot at Barro Colorado Island in Panama, we show that the spatially implicit model can be fitted to observed species richness and an independent estimate of the immigration parameter, with the fitted model predicting a species-abundance distribution close to the observed distribution. Our results complement those using sampling formulae that specify the multivariate probability distribution of species abundances from neutral models.


Asunto(s)
Emigración e Inmigración , Modelos Biológicos , Dinámica Poblacional , Biodiversidad , Ecosistema , Humanos , Islas , Panamá , Probabilidad
15.
Rev. colomb. cienc. pecu ; 32(1): 58-63, ene.-mar. 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1042783

RESUMEN

Abstract Background: Prolificacy has a high economic value and is one of the most important reproduction traits in small ruminants such as Markhoz goats, which is an endangered breed. Objective: To estimate genetic, environmental and phenotypic trends, and genetic parameters for litter size (LS), as a prolificacy trait of Markhoz goat does. Methods: The study was conducted using kidding records of 3,064 Markhoz does from 1992 to 2015. Genetic parameters were estimated with a logit link function using ASReml software, fitting a repeatability animal model, with birth year, kidding year, and kidding age as fixed effects, and direct additive genetic and permanent environmental effects as random effects. Genetic, phenotypic and environmental trends were estimated by using regression of breeding value, phenotypic value and environmental deviation averages on birth year, respectively. Results: Low and negligible heritability (0.002), repeatability (0.054) and coefficient of permanent environment (0.052) were estimated for LS, which indicates low possibility to achieve rapid genetic progress through phenotypic selection. A non-significant -actually, zero- genetic trend (0.00004 heads/kidding/year), and significant negative phenotypic and environmental trends (-0.01097 and -0.01100 heads/kidding/year, respectively) were estimated in this study. Conclusion: Optimizing environmental conditions and application of high-throughput technologies in selection programs could help reducing the extinction risk of Markhoz breed.


Resumen Antecedentes: La prolificidad tiene un alto valor económico y es uno de los rasgos reproductivos más importantes en pequeños rumiantes, tales como la raza caprina Markhoz. que está en peligro de extinción. Objetivo: Estimar las tendencias genéticas, ambientales y fenotípicas, y los parámetros genéticos para el tamaño de la camada (LS), como rasgo de prolificidad de las hembras de cabras Markhoz. Métodos: Se utilizaron registros de partos de 3.064 hembras Markhoz, de 1992 a 2015. Los parámetros genéticos se estimaron con una función de enlace logit utilizando el software ASReml, ajustando un modelo animal de repetibilidad, con el año de nacimiento, el año del parto y la edad al parto como efectos fijos, y genéticos aditivos directos y efectos ambientales permanentes como efectos aleatorios. Las tendencias genéticas, fenotípicas y ambientales se estimaron mediante la regresión del valor de la cría, el valor fenotípico y los promedios de desviación ambiental en el año de nacimiento, respectivamente. Resultados: Se estimó la heredabilidad -baja e insignificante- (0,002), repetibilidad (0,054) y coeficiente de ambiente permanente (0,052) para LS, lo que indica una baja posibilidad de lograr un progreso genético rápido a través de selección fenotípica. Se estimó una tendencia genética no significativa -de hecho, cero- (0,00004 cabezas/parto/año) y se estimaron tendencias fenotípicas y ambientales negativas significativas (-0,01097 y -0,01100 cabezas/parto/año, respectivamente) en el período estudiado. Conclusión: La optimización de las condiciones ambientales y la aplicación de tecnologías de alto rendimiento en los programas de selección podrían reducir el riesgo de extinción de la raza Markhoz.


Resumo Antecedentes: A prolificidade tem um elevado valor económico e é uma das mais importantes características de reprodução nos pequenos ruminantes, como a raça de caprinos Markhoz, que está em perigo de extinção. Objetivo: Estimar tendências genéticas, ambientais e fenotípicas, e parâmetros genéticos para o tamanho da serapilheira (LS), como um traço de proliferação de cabras Markhoz. Métodos: Este estudo foi realizado usando registros de parto de 3.064 Markhoz entre 1992 e 2015. Os parâmetros genéticos foram estimados com uma função logit link utilizando o software ASReml, ajustando um modelo animal de repetibilidade, com o ano de nascimento, o ano de parto ea idade de caçoar como efeitos fixos e efeitos ambientais diretos e genéticos diretos como efeitos aleatórios. As tendências genéticas, fenotípicas e ambientais foram estimadas pela regressão do valor de criação, valor fenotípico e médias de desvio ambiental no ano de nascimento, respectivamente. Resultados: Herdabilidade baixa e negligenciável (0,002), repetibilidade (0,054) e coeficiente de ambiente permanente (0,052) foram estimadas para LS, o que indica baixa possibilidade de alcançar um progresso genético rápido através da seleção fenotípica. Foi estimada uma tendência genética não-significativa e realmente zero (0,00004 cabeças/parto/ano) e tendências fenotípicas e ambientais negativas significativas (-0,01097 e -0,01100 cabeças/parto/ano, respectivamente) no período estudado. Conclusão: Parece que a otimização das condições ambientais ea aplicação de tecnologias de alto rendimento em programas de seleção poderiam reduzir o risco de extinção para a raça Markhoz.

16.
Conserv Biol ; 33(3): 523-533, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30809858

RESUMEN

Herbarium specimens are increasingly recognized as an important resource for conservation science and virtual herbaria are making specimens freely available to a wider range of users than ever before. Few virtual herbaria are designed with conservation use as a primary driver. Exceptionally, Brazil's Reflora Virtual Herbarium (RVH) was created to increase knowledge and conservation of the Brazilian flora. The RVH is closely integrated with the Flora of Brazil 2020 platform on which Brazil's new national Flora is under construction. Both resources are accessible via the Reflora home page and thousands of users move seamlessly between these Reflora resources. To understand how the Reflora resources are currently used and their impact on conservation science, we conducted a literature review and an online survey. We searched for publications of studies in which Reflora resources were used and publications resulting from Brazilian researchers who were part of Reflora's research and mobility program. The survey contained multiple choice questions and questions that required a written response. We targeted Reflora webpage visitors with the survey to capture a wider range of Reflora users than the literature review. Reflora resources were used for a variety of conservation-relevant purposes. Half the 806 scientific publications in which Reflora was cited and 81% of the 1069 survey respondents accessing Reflora resources mentioned conservation-relevant research outputs. Most conservation-relevant uses of the Reflora resources in scientific publications were research rather than implementation focused. The survey of Reflora users showed conservation uses and impacts of virtual herbaria were more numerous and diverse than the uses captured in the literature review. Virtual herbaria are vital resources for conservation science, but they must document use and impacts more comprehensively to ensure sustainability.


Revalorización del Conocimiento sobre Conservación por Medio de Mayor Acceso a la Información Botánica Resumen Los especímenes de los herbarios son reconocidos cada vez más como un recurso importante para la ciencia de la conservación, y, como nunca antes, los herbarios virtuales están poniendo a los especímenes a libre disposición para una gama mucho más amplia de usuarios. Pocos herbarios virtuales están diseñados con el uso para la conservación como conductor primario. Excepcionalmente, se creó el Herbario Virtual Reflora de Brasil (RVH, en inglés) para incrementar el conocimiento y la conservación de la flora brasileña. El RVH está integrado cuidadosamente con la plataforma Flora de Brasil 2020, sobre la cual está bajo construcción la nueva flora nacional de Brasil. Se accede a ambos recursos a través de la página inicial de Reflora y miles de usuarios navegan continuamente entre estos recursos de la página. Para entender cómo se usan actualmente los recursos de Reflora así como su impacto sobre la ciencia de la conservación, realizamos una revisión de la literatura y una encuesta en línea. Buscamos las publicaciones de estudios que usaron los recursos de Reflora y las publicaciones elaboradas por investigadores brasileños que formaron parte del programa de investigación y movilidad de Reflora. La encuesta incluyó preguntas de opción múltiple y preguntas que requerían una respuesta escrita. Enfocamos la encuesta en los visitantes a la página web de Reflora para obtener una gama más amplia de usuarios de Reflora que la que obtendríamos sólo con la revisión de la literatura. Los recursos de Reflora se usaron para una variedad de propósitos relevantes para la conservación. La mitad de las 806 publicaciones científicas en las que se citó a Reflora y el 81% de los 1069 encuestados que acceden a los recursos de Reflora mencionaron resultados de investigación relevantes para la conservación. La mayoría de los usos relevantes para la conservación de los recursos de Reflora en las publicaciones científicas estuvieron más enfocados en la investigación que en la implementación. La encuesta para los usuarios de Reflora mostró que los usos e impactos de los herbarios virtuales fueron más numerosos y diversos que los usos capturados en la revisión de la literatura. Los herbarios virtuales son recursos vitales para la ciencia de la conservación, pero deben documentar su uso y sus impactos exhaustivamente para asegurar su sustentabilidad.


Asunto(s)
Conservación de los Recursos Naturales , Brasil , Encuestas y Cuestionarios
17.
Plant Biol (Stuttg) ; 21(1): 122-132, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30195257

RESUMEN

Hybridization is a widespread phenomenon present in numerous lineages across the tree of life. Its evolutionary consequences range from effects on the origin and maintenance, to the loss of biodiversity. We studied genetic diversity and intra- and interspecific gene flow between two sympatric populations of closely-related species, Pitcairnia flammea and P. corcovadensis (Bromeliaceae), which are adapted to naturally fragmented Neotropical inselbergs, based on nuclear and plastidial DNA. Our main results indicate a strong reproductive isolation barrier, although low levels of interspecific gene flow were observed in both sympatric populations. The low rates of intraspecific gene flow observed for both P. corcovadensis and P. flammea populations corroborate the increasing body of evidence that inselberg bromeliad species are maintained as discrete evolutionary units despite the presence of low genetic connectivity. Nuclear patterns of genetic diversity and gene flow revealed that hybridization and introgression might not cause species extinction via genetic assimilation of the rare P. corcovadensis. In the face of reduced intraspecific gene exchange, hybridization and introgression may be important aspects of the Pitcairnia diversification process, with a positive evolutionary impact at the bromeliad community level, and thus contribute to increasing and maintaining genetic diversity in local isolated inselberg populations.


Asunto(s)
Bromeliaceae/genética , Hibridación Genética , Aislamiento Reproductivo , Brasil , ADN de Cloroplastos/genética , Flujo Génico , Variación Genética , Geografía , Haplotipos/genética , Especificidad de la Especie
18.
Zookeys ; (741): 255-269, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29706779

RESUMEN

The biodiversity crisis we live in, marked by high extinction rates, requires well-planned conservation efforts. To overcome this issue, red lists of threatened species are recognized as the main objective approach for evaluating the conservation status of species and therefore guiding conservation priorities. This work focuses on the Myriapoda (Chilopoda and Diplopoda) species listed in the Brazilian red list of fauna to enable discussion of the practical implications of red lists for conservation. Almost all myriapods assessed are endemic to Brazil (99 %) and 73 % are known from subterranean habitats only. Despite of 33 % being recorded from protected areas (PAs), downgrading, degazettement or downsizing of PAs and intense and unregulated ecotourism represent great threats. The PAs network in Brazil tends to fail in conserving myriapod species. The number of data deficient species (42 %) states the need of investing in ecological and taxonomic studies about the group, in order to fill in important knowledge gaps in species assessments nationally and globally. In this work we show that there is a lack of communication between national and global agencies concerning red lists, which results in a significant loss for science and for conservation. Despite investing in national and state red lists, individual countries must take the final step of submitting its data to IUCN global database, as significant international funding is available for IUCN red listed species conservation. Being one of the most diverse countries in the world, and facing the biggest cuts ever on national science funding, losing these important funding opportunities is a huge loss for Brazilian biodiversity conservation and for science. This study raises awareness on subterranean habitats conservation, due to its high endemism and fragility. Since the first edition of the Brazilian Red List in 1968, centipedes are now included for the first time, and millipedes for the second time. The presence of these myriapods in the list brings attention to the group, which usually receives little or no attention in conservation programs and environmental impact assessments. Rather than a specific case for Myriapoda and for Brazil, the points discussed here can be related to arthropods and the tropics, as the most biodiverse countries are emerging economies facing similar challenges in PAs network management, species extinction risks and science funding.

19.
Ecology ; 99(2): 497, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29266462

RESUMEN

South America holds 30% of the world's avifauna, with the Atlantic Forest representing one of the richest regions of the Neotropics. Here we have compiled a data set on Brazilian Atlantic Forest bird occurrence (150,423) and abundance samples (N = 832 bird species; 33,119 bird individuals) using multiple methods, including qualitative surveys, mist nets, point counts, and line transects). We used four main sources of data: museum collections, on-line databases, literature sources, and unpublished reports. The data set comprises 4,122 localities and data from 1815 to 2017. Most studies were conducted in the Florestas de Interior (1,510 localities) and Serra do Mar (1,280 localities) biogeographic sub-regions. Considering the three main quantitative methods (mist net, point count, and line transect), we compiled abundance data for 745 species in 576 communities. In the data set, the most frequent species were Basileuterus culicivorus, Cyclaris gujanensis, and Conophaga lineata. There were 71 singletons, such as Lipaugus conditus and Calyptura cristata. We suggest that this small number of records reinforces the critical situation of these taxa in the Atlantic Forest. The information provided in this data set can be used for macroecological studies and to foster conservation strategies in this biodiversity hotspot. No copyright restrictions are associated with the data set. Please cite this Data Paper if data are used in publications and teaching events.

20.
Ecol Appl ; 27(5): 1633-1645, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28397328

RESUMEN

Climate change is a major threat to biodiversity; the development of models that reliably predict its effects on species distributions is a priority for conservation biogeography. Two of the main issues for accurate temporal predictions from Species Distribution Models (SDM) are model extrapolation and unrealistic dispersal scenarios. We assessed the consequences of these issues on the accuracy of climate-driven SDM predictions for the dispersal-limited Darwin's frog Rhinoderma darwinii in South America. We calibrated models using historical data (1950-1975) and projected them across 40 yr to predict distribution under current climatic conditions, assessing predictive accuracy through the area under the ROC curve (AUC) and True Skill Statistics (TSS), contrasting binary model predictions against temporal-independent validation data set (i.e., current presences/absences). To assess the effects of incorporating dispersal processes we compared the predictive accuracy of dispersal constrained models with no dispersal limited SDMs; and to assess the effects of model extrapolation on the predictive accuracy of SDMs, we compared this between extrapolated and no extrapolated areas. The incorporation of dispersal processes enhanced predictive accuracy, mainly due to a decrease in the false presence rate of model predictions, which is consistent with discrimination of suitable but inaccessible habitat. This also had consequences on range size changes over time, which is the most used proxy for extinction risk from climate change. The area of current climatic conditions that was absent in the baseline conditions (i.e., extrapolated areas) represents 39% of the study area, leading to a significant decrease in predictive accuracy of model predictions for those areas. Our results highlight (1) incorporating dispersal processes can improve predictive accuracy of temporal transference of SDMs and reduce uncertainties of extinction risk assessments from global change; (2) as geographical areas subjected to novel climates are expected to arise, they must be reported as they show less accurate predictions under future climate scenarios. Consequently, environmental extrapolation and dispersal processes should be explicitly incorporated to report and reduce uncertainties in temporal predictions of SDMs, respectively. Doing so, we expect to improve the reliability of the information we provide for conservation decision makers under future climate change scenarios.


Asunto(s)
Distribución Animal , Anuros/fisiología , Cambio Climático , Conservación de los Recursos Naturales , Animales , Argentina , Chile , Modelos Biológicos , Factores de Tiempo
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