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1.
PLoS Biol ; 20(5): e3001544, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35617356

RESUMEN

The Red List of Threatened Species, published by the International Union for Conservation of Nature (IUCN), is a crucial tool for conservation decision-making. However, despite substantial effort, numerous species remain unassessed or have insufficient data available to be assigned a Red List extinction risk category. Moreover, the Red Listing process is subject to various sources of uncertainty and bias. The development of robust automated assessment methods could serve as an efficient and highly useful tool to accelerate the assessment process and offer provisional assessments. Here, we aimed to (1) present a machine learning-based automated extinction risk assessment method that can be used on less known species; (2) offer provisional assessments for all reptiles-the only major tetrapod group without a comprehensive Red List assessment; and (3) evaluate potential effects of human decision biases on the outcome of assessments. We use the method presented here to assess 4,369 reptile species that are currently unassessed or classified as Data Deficient by the IUCN. The models used in our predictions were 90% accurate in classifying species as threatened/nonthreatened, and 84% accurate in predicting specific extinction risk categories. Unassessed and Data Deficient reptiles were considerably more likely to be threatened than assessed species, adding to mounting evidence that these species warrant more conservation attention. The overall proportion of threatened species greatly increased when we included our provisional assessments. Assessor identities strongly affected prediction outcomes, suggesting that assessor effects need to be carefully considered in extinction risk assessments. Regions and taxa we identified as likely to be more threatened should be given increased attention in new assessments and conservation planning. Lastly, the method we present here can be easily implemented to help bridge the assessment gap for other less known taxa.


Asunto(s)
Conservación de los Recursos Naturales , Extinción Biológica , Animales , Biodiversidad , Especies en Peligro de Extinción , Humanos , Filogenia , Reptiles
2.
An Acad Bras Cienc ; 96(2): e20230262, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38747834

RESUMEN

Brazil harbors the highest richness of Convolvulaceae with 424 species recognized mainly distributed in the Amazon, Atlantic Forest, Caatinga and Cerrado phytogeographic domains. Seventeen of these species are representatives of Bonamia, with ten endemic to the country. The aim of the study was to map the distribution of this group to understand its richness, its sampling and detecting areas of endemism, valuable information for conservation. We collected data gathered from herbaria and from the online database. The data were refined (1) excluding of records not at the species level; (2) records with no identification of collection site or with only the identification of the state of collection. There was calculated the richness, the number of records and an estimate of richness per cell. We conducted a parsimony analysis of endemism for distribution analysis. Finally, the knowledge of richness for the species was analyzed. There were gathered 420 occurrence records, in 87 grid cells. Most grid cells observed in the study presented one species. Two endemic areas were found for the genus. The results contribute to the understanding of the distribution of the group in Brazil, highlighting shortfalls in collections.


Asunto(s)
Biodiversidad , Brasil
3.
Conserv Biol ; 37(5): e14100, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37070377

RESUMEN

The first target of the Convention for Biological Diversity (Aichi target 1) was to increase public awareness of the values of biodiversity and actions needed to conserve it-a key prerequisite for other conservation targets. Monitoring success in achieving this target at a global scale has been difficult; however, increased digitization of human life in recent decades has made it easier to measure people's interests at an unprecedented scale and allows for a more comprehensive evaluation of Aichi target 1 than previously attempted. We used Google search volume data for over a thousand search terms related to different aspects of biodiversity and conservation to evaluate global interest in biodiversity and its conservation. We also investigated the correlation of interest in biodiversity and conservation across countries to variables related to biodiversity, economy, demography, research, education, internet use, and presence of environmental organizations. From 2013 to 2020, global searches for biodiversity components increased, driven mostly by searches for charismatic fauna (59% of searches were for mammal species). Searches for conservation actions, driven mostly by searches for national parks, decreased since 2019, likely due to the COVID-19 pandemic. Economic inequality was negatively correlated with interest in biodiversity and conservation, whereas purchasing power was indirectly positively correlated with higher levels of education and research. Our results suggest partial success toward achieving Aichi target 1 in that interest in biodiversity increased widely, but not for conservation. We suggest that increased outreach and education efforts aimed at neglected aspects of biodiversity and conservation are still needed. Popular topics in biodiversity and conservation could be leveraged to increase awareness of other topics with attention to local socioeconomic contexts.


Evaluación del interés mundial en la biodiversidad y la conservación Resumen La primera meta del Convenio sobre la Diversidad Biológica (Meta 1 de Aichi) era aumentar la conciencia pública sobre los valores de la biodiversidad y las acciones necesarias para conservarla, un requisito previo clave para otras metas de conservación. Ha sido difícil monitorear el éxito en la obtención de esta meta a escala mundial; sin embargo, la creciente digitalización de la vida humana en las últimas décadas ha facilitado la medición de los intereses de la gente a una escala sin precedentes y permite una evaluación más exhaustiva de la Meta 1 de Aichi que la que se había intentado previamente. Utilizamos datos sobre el volumen de búsquedas en Google de más de mil términos relacionados con distintos aspectos de la biodiversidad y la conservación para evaluar el interés mundial en la biodiversidad y su conservación. También investigamos la correlación del interés por la biodiversidad y la conservación en los distintos países con variables relacionadas a la biodiversidad, la economía, la demografía, la investigación, la educación, el uso del internet y la presencia de organizaciones ambientalistas. Las búsquedas mundiales sobre los componentes de la biodiversidad aumentaron de 2013 a 2020, impulsadas sobre todo por búsquedas de especies carismática (el 59% de las búsquedas correspondían a especies de mamíferos). Las búsquedas de acciones de conservación, impulsadas principalmente por búsquedas de parques nacionales, han disminuido desde 2019, probablemente debido a la pandemia de COVID-19. La desigualdad económica se correlacionó negativamente con el interés en la biodiversidad y la conservación, mientras que el poder adquisitivo se correlacionó indirectamente de manera positiva con niveles más altos de educación e investigación. Nuestros resultados sugieren un éxito parcial en la obtención de la Meta 1 de Aichi en el sentido de que aumentó ampliamente el interés por la biodiversidad, pero no por la conservación. Sugerimos que se necesitan mayores esfuerzos de divulgación y educación dirigidos a aspectos desatendidos de la biodiversidad y la conservación. Los temas populares de biodiversidad y conservación podrían aprovecharse para aumentar la conciencia sobre otros temas si se presta atención a los contextos socioeconómicos locales.


Asunto(s)
COVID-19 , Pandemias , Animales , Humanos , Conservación de los Recursos Naturales/métodos , Biodiversidad , Mamíferos
5.
J Therm Biol ; 73: 50-60, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29549991

RESUMEN

Temperature increases can impact biodiversity and predicting their effects is one of the main challenges facing global climate-change research. Ectotherms are sensitive to temperature change and, although predictions indicate that tropical species are highly vulnerable to global warming, they remain one of the least studied groups with respect to the extent of physiological variation and local extinction risks. We model the extinction risks for a tropical heliothermic teiid lizard (Kentropyx calcarata) integrating previously obtained information on intraspecific phylogeographic structure, eco-physiological traits and contemporary species distributions in the Amazon rainforest and its ecotone to the Cerrado savannah. We also investigated how thermal-biology traits vary throughout the species' geographic range and the consequences of such variation for lineage vulnerability. We show substantial variation in thermal tolerance of individuals among thermally distinct sites. Thermal critical limits were highly correlated with operative environmental temperatures. Our physiological/climatic model predicted relative extinction risks for local populations within clades of K. calcarata for 2050 ranging between 26.1% and 70.8%, while for 2070, extinction risks ranged from 52.8% to 92.8%. Our results support the hypothesis that tropical-lizard taxa are at high risk of local extinction caused by increasing temperatures. However, the thermo-physiological differences found across the species' distribution suggest that local adaptation may allow persistence of this tropical ectotherm in global warming scenarios. These results will serve as basis to further research to investigate the strength of local adaptation to climate change. Persistence of Kentropyx calcarata also depends on forest preservation, but the Amazon rainforest is currently under high deforestation rates. We argue that higher conservation priority is necessary so the Amazon rainforest can fulfill its capacity to absorb the impacts of temperature increase on tropical ectotherms during climate change.


Asunto(s)
Aclimatación , Temperatura Corporal , Extinción Biológica , Calentamiento Global , Lagartos/fisiología , Animales , Femenino , Locomoción , Masculino , Modelos Biológicos , Bosque Lluvioso , Factores de Riesgo , Temperatura , Clima Tropical
6.
J Biol Res (Thessalon) ; 28(1): 3, 2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33557958

RESUMEN

Amniote vertebrates share a suite of extra-embryonic membranes that distinguish them from anamniotes. Other than that, however, their reproductive characteristics could not be more different. They differ in basic ectothermic vs endothermic physiology, in that two clades evolved powered flight, and one clade evolved a protective shell. In terms of reproductive strategies, some produce eggs and others give birth to live young, at various degrees of development. Crucially, endotherms provide lengthy parental care, including thermal and food provisioning-whereas ectotherms seldom do. These differences could be expected to manifest themselves in major differences between clades in quantitative reproductive traits. We review the reproductive characteristics, and the distributions of brood sizes, breeding frequencies, offspring sizes and their derivatives (yearly fecundity and biomass production rates) of the four major amniote clades (mammals, birds, turtles and squamates), and several major subclades (birds: Palaeognathae, Galloanserae, Neoaves; mammals: Metatheria and Eutheria). While there are differences between these clades in some of these traits, they generally show similar ranges, distribution shapes and central tendencies across birds, placental mammals and squamates. Marsupials and turtles, however, differ in having smaller offspring, a strategy which subsequently influences other traits.

7.
PLoS One ; 13(3): e0192834, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29513695

RESUMEN

We summarize thermal-biology data of 69 species of Amazonian lizards, including mode of thermoregulation and field-active body temperatures (Tb). We also provide new data on preferred temperatures (Tpref), voluntary and thermal-tolerance ranges, and thermal-performance curves (TPC's) for 27 species from nine sites in the Brazilian Amazonia. We tested for phylogenetic signal and pairwise correlations among thermal traits. We found that species generally categorized as thermoregulators have the highest mean values for all thermal traits, and broader ranges for Tb, critical thermal maximum (CTmax) and optimal (Topt) temperatures. Species generally categorized as thermoconformers have large ranges for Tpref, critical thermal minimum (CTmin), and minimum voluntary (VTmin) temperatures for performance. Despite these differences, our results show that all thermal characteristics overlap between both groups and suggest that Amazonian lizards do not fit into discrete thermoregulatory categories. The traits are all correlated, with the exceptions of (1) Topt, which does not correlate with CTmax, and (2) CTmin, and correlates only with Topt. Weak phylogenetic signals for Tb, Tpref and VTmin indicate that these characters may be shaped by local environmental conditions and influenced by phylogeny. We found that open-habitat species perform well under present environmental conditions, without experiencing detectable thermal stress from high environmental temperatures induced in lab experiments. For forest-dwelling lizards, we expect warming trends in Amazonia to induce thermal stress, as temperatures surpass the thermal tolerances for these species.


Asunto(s)
Aclimatación/fisiología , Regulación de la Temperatura Corporal/fisiología , Temperatura Corporal/fisiología , Lagartos/fisiología , Temperatura , Animales , Brasil , Ecosistema , Geografía , Lagartos/clasificación , Especificidad de la Especie
8.
Biota Neotrop. (Online, Ed. ingl.) ; 23(4): e20231520, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1527942

RESUMEN

Abstract It is repeatedly stressed the need to characterize the extant biodiversity in tropical ecosystems. However, inventory studies are still progressing slowly in dry ecosystems, leading to the underestimation of their true biodiversity and hindering conservation efforts. In this study, we present primary and secondary data, along with an updated list of amphibians and reptiles from two localities in the São Francisco-Gurguéia region in Piauí. Additionally, we compare the species composition between nine areas within the Caatinga, which were sampled using standardized methods over the past ten years, to examine broader spatial patterns of community composition. To survey reptiles and amphibians, we employed similar methods and sampling efforts in two areas within the Serra das Confusões National Park (SCNP) region. Our surveys recorded a total of 73 species of amphibians and reptiles, of which 24 are new distribution records for the SCNP region. Consequently, our findings increase the known herpetofauna in the region to 94 species. Despite their proximity, the two sites in the SCNP region exhibited only 42% similarity in species composition, and they differed significantly from other areas within the Caatinga. Furthermore, even the closer Caatinga areas presented differences in species composition, highlighting the necessity to evaluate biodiversity across the landscape and contribute to understanding biogeographic patterns.


Resumo É repetidamente enfatizada a necessidade de caracterizar a biodiversidade vivente em ecossistemas tropicais. No entanto, os estudos de inventário ainda estão progredindo lentamente em ecossistemas secos, levando à subestimação de sua verdadeira biodiversidade e dificultando os esforços de conservação. Neste estudo, apresentamos dados primários e secundários, juntamente com uma lista atualizada de anfíbios e répteis de duas localidades na região de São Francisco-Gurguéia, do Piauí. Além disso, comparamos a composição de espécies entre nove áreas dentro da Caatinga, que foram amostradas usando métodos padronizados nos últimos dez anos, para examinar padrões espaciais mais amplos de composição da comunidade. Para estudar répteis e anfíbios, utilizamos métodos e esforços de amostragem semelhantes em duas áreas na região do Parque Nacional da Serra das Confusões (PNSC). Nossos levantamentos registraram um total de 73 espécies de anfíbios e répteis, das quais 24 são novos registros de distribuição para a região do PNSC. Consequentemente, nossos resultados aumentam a herpetofauna conhecida na região para 94 espécies. Apesar da proximidade, os dois locais na região do PNSC exibiram apenas 42% de similaridade na composição de espécies e diferiram significativamente de outras áreas dentro da Caatinga. Mesmo áreas mais próximas da Caatinga apresentaram diferenças na composição de espécies, destacando a necessidade de avaliar a biodiversidade em toda a paisagem e contribuir para a compreensão de padrões biogeográficos.

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