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1.
Hist. ciênc. saúde-Manguinhos ; 28(supl.1): 161-183, out.-dez. 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1360461

RESUMO

Abstract The Caribbean monk seal (Monachus tropicalis), the only seal species native to Central America, was declared extinct in 2008, with the last confirmed sighting in 1952. This species historically had a broad range throughout the gulf of Mexico. This article discusses the history of Western science on the monk seal, from its first recorded sighting by a Western colonizer in 1492 to scientific collection in the 1800s and 1900s, as a history of the erasure of this species. Museum practices of collecting and displaying Caribbean monk seals have directly contributed to this erasure, and ways of writing a new history by giving the Caribbean monk seal the capacity to refuse erasure are suggested.


Resumo A foca-monge-do-caribe (Monachus tropicalis), a única espécie de focas nativa da América Central, foi declarada extinta em 2008, tendo o último registro de avistamento confirmado em 1952. Historicamente, essa espécie ocupou vastas áreas do golfo do México. Este artigo discute a história da ciência ocidental sobre a foca-monge, desde o primeiro registro de seu avistamento por um colonizador ocidental, em 1492, até a coleção científica nos anos 1800 e 1900, como uma história de desaparecimento da espécie. As práticas museológicas de coleta e exposição de focas-monge-do-caribe contribuíram diretamente para tal desaparecimento, e aqui são sugeridas maneiras de escrever uma nova história concedendo à foca-monge-do-caribe a possibilidade de recusa ao desaparecimento.


Assuntos
Humanos , História Natural , Focas Verdadeiras , Meio Ambiente , Extinção Biológica , Fauna Aquática , História do Século XX , Animais , Museus
2.
Suma psicol ; 28(1): 37-42, Jan.-June 2021. graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1280693

RESUMO

Resumen Introducción y objetivo: Los procesos de aprendizaje y motivación han sido centrales para la comprensión de los mecanismos que subyacen al tabaquismo. En particular, existe evidencia creciente sobre la importancia de valores motivacionales de incentivo para entender el inicio y mantenimiento del tabaquismo. El objetivo general de este experimento fue evaluar el papel de la nicotina aguda sobre el valor de incentivo de una recompensa natural, (comida) asociada con un estímulo ambiental, (palanca experimental). Método: Se utilizaron ratas Wistar. Se administró nicotina (0.4 mg/kg) de manera aguda en momentos específicos del entrenamiento, utilizando un procedimiento de diez sesiones de adquisición y cuatro sesiones extinción en una tarea pavloviana de automoldeamiento. El diseño experimental incluyó tres grupos, el grupo control de solución salina y grupos de nicotina durante la adquisición y la extinción. Resultados: Se encontró que la administración aguda de nicotina, de manera específica y en comparación con los otros dos grupos experimentales, resultó en un efecto de retardo durante la fase de extinción, y que una administración similar de nicotina no resultó en efectos observables durante el desempeño comportamental en adquisición. Conclusiones: Estos resultados apoyan el papel de la nicotina como fortalecedora del valor de incentivo de las claves ambientales durante la extinción para una tarea de automoldeamiento.


Abstract Introduction and goal: Learning and motivational processes have been central for a modern understanding of tobacco addiction. There is evidence that supports the importance of incentive motivational processes for the maintenance of tobacco addiction. The main goal of the present experiment was to evaluate the effects of acute nicotine on the incentive value of a natural reward, (food) paired with an environmental cue (pressing lever). Method: Wistar rats were used. Accute nicotine (0.4 mg/kg) was administered on key sessions, using a pavlovian autoshaping procedure involving ten acquisition and four extinction sessions. The experimental design included three groups, a saline administration control group and groups with specific nicotine administration during either acquisition or extinction. Results: We found that acute administration of nicotine, in contrast with saline only or previous nicotine administration during acquisition, had an enhancing effect on responding for the environmental cue during autoshaping extinction, but we did not find evidence that acute nicotine affected acquisition performance. Conclusion: Our results are consistent with a role of nicotine enhancing the incentive value of stimuli during extinction from a pavlovian autoshaping task.


Assuntos
Nicotina , Tabagismo , Extinção Biológica , Motivação
3.
Braz. arch. biol. technol ; 64: e21200760, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1278452

RESUMO

Abstract In this study, in vitro propagation and acclimatization of Helianthemum germanicopolitanum Bornm. plant, a local endemic in Çankırı Province (Turkey) with arid and semi-arid lands, and an endangered species taking part among medicinal and aromatic plants were accomplished, which is under-researched. In this study, three basal media [a) Murashige and Skoog b) Gamborg's B5, and c) Nitsch & Nitsch], two gelling agents (agar 7 g/L, and gelrite 2.1 g/L), eight cytokinins and eight auxin doses of plant growth regulators [a) 6-benzyladenin, b) Kinetin-(0, 0.5, 1, and 2 mg/L), c) Indole-3-butyric acid, d) α-napthaleneacetic acid-(0, 0.25, 0.5, and 1 mg/L)] prepared in 64 different combinations with 30 g/L sucrose was added to the basal media and adjusted to pH 5.7 for in vitro propagation of H. germanicopolitanum. During in vitro propagation of the plant, external and internal infections were frequently encountered and this was solved by the developed protocol. The best shoot growth (1.141 cm) and shoot length (0.572 cm) were obtained in the Gamborg's B5 medium in combination with Kinetin (0.5 mg/L)+Indole-3-butyric acid (0.5 mg/L)+gelrite. The maximum number of shoots (19.50) and the best multiplication rate (94%) were obtained in the media containing benzyladenin (1 mg/L)+Indole-3-butyric acid (0.5 mg/L) plant growth regulator in Murashige and Skoog medium solidified with agar. At the rooting stage, the maximum number of roots (30) was reached in the Murashige and Skoog medium containing gelrite and the best rooting rate (92%) with agar. A hundred plants representing the best shoot and root growth were taken to acclimatization stage, and 32 of these plants adapted to external conditions.


Assuntos
Cistaceae , Ar Condicionado , Extinção Biológica , Plantas Medicinais
4.
Acta sci., Biol. sci ; 42: e47448, fev. 2020. ilus, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460912

RESUMO

The in vitro seed germination which results in the production of disease-free seedlings and greenhouse germination of the seeds of Mansonia altissima was investigated in order to establish a better way of germination of the timber species. Five levels of GA3 treatment were used in in vitro germination with three replicate and two seeds were inoculated in each of the jam bottle. Whereas, in greenhouse germination, five levels of different treatments were used, replicated three times and each Petri plate contained 15 seeds. The experiment was repeated twice and the data from each experiment was put together and used for the statistical analysis. The results showed that seeds germination occurred eight days after inoculation in in vitro but in the case of greenhouse germination, it took only five days. For in vitro rapid germination of Mansonia altissima, the MS medium should be supplemented with 1.0 μm of GA3. Equally, in greenhouse germination, the seeds need to be soaked in 1.0 mM of GA3 for 24 hours. Alternatively, in the absence of GA3, the seeds can be soaked in water for 24 hours before broadcasting the seeds on the seedbed for germination, as this will help to identify nonviable seeds.


Assuntos
Extinção Biológica , Germinação , Malvaceae/crescimento & desenvolvimento , Técnicas In Vitro
5.
Rev. Asoc. Colomb. Cien. Biol. (En línea) ; 1(32): 183-198, 20200000. tab
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1379243

RESUMO

La biodiversidad comprende la variabilidad de organismos y los sistemas ecológicos de los que forma parte, y constituye el sustento de la humanidad. Sin embargo, las actividades humanas han modificado a la biodiversidad en sus distintos niveles a un grado sin precedentes. Por lo cual, el objetivo de este trabajo fue analizar y describir el estado de la biodiversidad global y las cinco importantes causas de su declive: degradación y pérdida del hábitat, introducción de especies exóticas, sobreexplotación de recursos, contaminación y el cambio climático. La crisis actual se califica como la sexta extinción masiva, donde los anfibios y los corales formadores de arrecifes son los que presentan mayor riesgo de desaparecer. Debido a que para los próximos años el panorama no es el mejor, es urgente la toma acciones integrales para relentizar los procesos que dañan la integridad y funcionamiento de la diversidad biológica.


Biodiversity comprises the variability of organisms and the ecological systems of which it is part, and constitutes the livelihood of humanity. However, human activities have modified biodiversity at its various levels to an unprecedented level. Therefore, the aim of this work was to analyze and describe the state of global biodiversity and the five important causes of its decline: degradation and loss of habitat, introduction of exotic species, overexploitation of resources, pollution and climate change. The current crisis is classified as the sixth mass extinction, with amphibians and reef-building corals most at risk of disappearing. Because for the next few years the outlook is not the best, it is urgent to take concrete actions to slow down the processes that damage the integrity and functioning of biological diversity.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Extinção Biológica
6.
Neotrop. ichthyol ; 17(1): e180071, 2019. tab, graf
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1002707

RESUMO

Brycon nattereri is an endangered Neotropical fish reported along conserved stretches of the upper Paraná, Tocantins and São Francisco rivers. Populations of this species have been very rare in some Paraná River sub basins. This study analyzes the genetic diversity and population structure of B. nattereri in a restricted area of occurrence recently identified in upper Paraná River basin. Seven microsatellite loci and 497 bp of D-Loop mitochondrial region were examined in 92 individuals from four points along the area of occurrence. Both molecular markers indicated a single population distributed along a stretch of the river approximately 80 km long. Although some of the data suggest an ancient bottleneck, current levels of genetic diversity (H E = 0.574 and h = 0.616) were similar to those of other species of the genus Brycon. The results suggest that the population of B. nattereri has been able to maintain satisfactory levels of genetic diversity, in spite of the small area of occurrence. These data have highlighted an important conservation area and action may prove essential to improve the quality of the environment, and especially the water and riparian plant life, if the area is to be managed and conserved efficiently.(AU)


Brycon nattereri é um peixe Neotropical ameaçado de extinção reportado para trechos conservados dos rios Paraná, Tocantins e São Francisco. Populações desta espécie têm sido muito raras em algumas sub-bacias do rio Paraná. Este estudo analisou a diversidade genética e a estrutura populacional de B. nattereri em uma área de ocorrência restrita recentemente identificada na bacia do alto rio Paraná. Sete locos microssatélites e 497 pb da região mitocondrial D-Loop foram examinados para 92 indivíduos de quatro pontos ao longo da área de ocorrência. Ambos os marcadores moleculares indicaram uma única população distribuída em um trecho de aproximadamente 80 km do rio. Embora alguns dados tenham sugerido um antigo gargalo genético, os atuais níveis de diversidade genética (H E = 0,574, h = 0,616) foram similares aos de outras espécies do gênero Brycon. Estes resultados sugerem que a população de B. nattereri tem mantido níveis satisfatórios de diversidade genética, apesar da pequena área de ocorrência. Estes dados destacaram uma importante área de conservação e ações podem melhorar a qualidade do ambiente, especialmente para a vida aquática e mata ciliar, se a área for eficientemente manejada e conservada.(AU)


Assuntos
Animais , Variação Genética , Extinção Biológica , Caraciformes/classificação , Caraciformes/genética
7.
Rev. biol. trop ; 66(3): 1197-1207, jul.-sep. 2018. tab, graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-977377

RESUMO

Resumen Desde el 2011, los pescadores artesanales de Taganga (Caribe colombiano) capturaron al pez león en nasas para el Parque Nacional Natural Tayrona. Este hecho generó la percepción de que el pez león causó la disminución de la pesca. Para determinar los cambios en las especies capturadas y conocer la abundancia del pez león en este arte, se analizó el desembarco histórico en nasas entre 1993 y 2014, así como, el desembarque a tres unidades económicas de pesca entre marzo 2012 y julio 2014. El análisis histórico mostró que la disminución de las especies y los kilogramos desembarcados ocurrió desde el 2000. Un total de 4 913 individuos fueron desembarcados entre marzo 2012 y julio 2014, de los cuales el 85 % fueron especies de interés comercial y el resto fueron utilizadas por los pescadores para su consumo. Los desembarcos entre marzo 2012 y julio 2014 estuvieron condicionados a factores climáticos, donde la co-ocurrencia de Pterois volitans y las principales especies comerciales y de autoconsumo no mostró evidencia de que el pez león afecte sus abundancias. Se confirma así la presencia del pez león como un nuevo integrante en los desembarcos en nasas en la Bahía de Taganga.


Abstract Incidental catch in traps of the lionfish Pterois volitans (Scorpaeniformes: Scorpaenidae) in the Colombian Caribbean. Since 2011, small-scale fishermen from Taganga Bay (Colombian Caribbean) have been catching lionfish in traps in the Tayrona National Natural Park, which had caused them to believe that the lionfish is the cause of the decrease in overall fishing. In order to determine the changes in the species captured and to know the abundance of the lionfish in this fishing method, we analyzed the historical landings in traps between 1993 and 2014, as well as the landing of three fishing units between March 2012 and July 2014. The historical analysis showed that the decline in species and kilograms landed has been occurring since 2000. A total of 4 913 specimens were landed between March 2012 and July 2014, of which 85 % were species of commercial interest, and the rest were used by fishermen for consumption. Landings between 2012 and 2014 were conditioned by climatic conditions, where the co-occurrence between Pterois volitans and the main commercial species and self-consumption did not provide evidence of the lionfish affecting its abundance. This confirms the presence of the lionfish as a new member in the landings in traps the Taganga Bay. Rev. Biol. Trop. 66(3): 1197-1207. Epub 2018 September 01.


Assuntos
Animais , Colômbia , Saneamento de Portos , Extinção Biológica , Pesqueiros , Peixes
8.
Neotrop. ichthyol ; 16(4): [e180066], out. 2018. mapas, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-964069

RESUMO

The present report represents the first cytogenetic description of Steindachneridion doceanum, great catfish which is currently at high extinction risk and it is listed as threatened on the red list of the Brazilian Ministry of the Environment, also are suggested karyotype relationships with other species of the same genus endemic from other river basins. The results revealed a diploid number of 2n = 56 and the karyotype composed of 18 metacentric, 20 submetacentric, 10 subtelocentric and 8 acrocentric chromosomes (NF = 104). The AgNORs and CMA3 signals were coincident in location occupying the short arm of an acrocentric chromosome pair (25th), in a secondary constriction. The 5S rDNA genes were localized on the short arms of one subtelocentric pair. C-banding revealed terminal blocks on the short arms on many chromosomes as well as terminal positive bands at the both ends of a submetacentric pair. C banding also revealed a large heterochromatic block in the secondary constriction (25th) region that was coincident with the AgNORs sites and CMA3+ bright bands. In spite S. doceanum represent an endemic taxon, in spite their geographic isolation their cytogenetic characteristics show similarities with other species of the genus.(AU)


O presente trabalho apresenta a primeira descrição citogenética de Steindachneridion doceanum, grande bagre que se encontra atualmente em alto risco de extinção e listado como ameaçado na lista vermelha do Ministério do Meio Ambiente, também sugere relações cariotípicas com outras espécies do mesmo gênero, endêmicas de outras bacias hidrográficas. Os resultados revelaram um número diplóide de 56 cromossomos e o cariótipo composto por 18 elementos metacêntricos, 20 submetacêntricos, 10 subtelocêntricos e 8 acrocêntricos (NF = 104). As marcações AgNORs e CMA3 foram coincidentes ocupando o braço curto de um par de cromossomos acrocêntricos (par 25), em uma constrição secundária. Os genes 5S rDNA foram detectados nos braços curtos de um par subtelocêntrico. A banda C revelou blocos terminais nos braços curtos em vários cromossomos, bem como blocos terminais nas duas extremidades de um par submetacêntrico. A banda C também evidenciou um grande bloco heterocromático na constrição secundária (par 25) coincidente com os sítios AgNORs e as bandas CMA3 positivas. Apesar de S. doceanum representar um táxon endêmico, suas características citogenéticas mostram semelhanças com outras espécies do gênero das quais se encontra geograficamente isolado.(AU)


Assuntos
Animais , Peixes-Gato/genética , Extinção Biológica , Cariótipo
9.
An. acad. bras. ciênc ; 89(3): 1465-1485, July-Sept. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-886738

RESUMO

ABSTRACT The non-avian dinosaurs died out at the end of the Cretaceous, ~66 million years ago, after an asteroid impact. The prevailing hypothesis is that the effects of the impact suddenly killed the dinosaurs, but the poor fossil record of latest Cretaceous (Campanian-Maastrichtian) dinosaurs from outside Laurasia (and even more particularly, North America) makes it difficult to test specific extinction scenarios. Over the past few decades, a wealth of new discoveries from the Bauru Group of Brazil has revealed a unique window into the evolution of terminal Cretaceous dinosaurs from the southern continents. We review this record and demonstrate that there was a diversity of dinosaurs, of varying body sizes, diets, and ecological roles, that survived to the very end of the Cretaceous (Maastrichtian: 72-66 million years ago) in Brazil, including a core fauna of titanosaurian sauropods and abelisaurid and carcharodontosaurid theropods, along with a variety of small-to-mid-sized theropods. We argue that this pattern best fits the hypothesis that southern dinosaurs, like their northern counterparts, were still diversifying and occupying prominent roles in their ecosystems before the asteroid suddenly caused their extinction. However, this hypothesis remains to be tested with more refined paleontological and geochronological data, and we give suggestions for future work.


Assuntos
Animais , Dinossauros/classificação , Fósseis/anatomia & histologia , Paleontologia , Brasil , Dinossauros/anatomia & histologia , Extinção Biológica
10.
An. acad. bras. ciênc ; 89(1,supl): 491-496, May. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-886667

RESUMO

ABSTRACT Biodiversity decline has been the focus of discussions in the last decade, especially on the amphibian species decline. After a scientometric analysis using international databases, we found that the number of peer-reviewed articles considering education practices related to the theme increased along with the number of ecological researches. However, the increase in ecological researches is much higher than the increase in publications of education practices. Studies suggest that conservation attitudes are important and that education practices are an important tool for improving human perceptions on this subject. In this sense, increase the publication of projects and programs results related to local education practices in international journals could help the dissemination of efficient methods for conservation, as well as facilitating access to information internationally, since species decline, especially for amphibians, is a global concern. Then, we suggest that educational practices, at least when related to conservation, should follow a more standardized protocol, and be published in international journals, as the efficiency of such practices should be evaluated and methods once published could help other nations to improve their ecological literacy.


Assuntos
Humanos , Animais , Bibliometria , Revisão da Pesquisa por Pares/tendências , Anfíbios , Publicações Periódicas como Assunto , Bases de Dados Bibliográficas , Ecologia/estatística & dados numéricos , Extinção Biológica
11.
Rev. chil. infectol ; 30(3): 237-243, jun. 2013. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-679902

RESUMO

The incidence of whooping cough in Chile ranges from 4.1 and 7.5 per hundred thousand inhabitants. B. pertussis detection is performed by Real Time PCR (Q-PCR) directed to the insertion sequence IS481. However, this sequence is also found in the genome of B. bronchiseptica and B. holmesii. The latter is also a respiratory pathogen whose clinical features are similar to B. pertussis. However, it is important to differentiate between these species because in immunosuppressed patients B. holmesii is more likely to cause bacteremia and is less susceptible to erythromycin. The goal of this work is to measure prospectively and retrospectively the presence of B. holmesii in samples reported positive for B. pertussis in the period 2010-2011. During this period, 1994 nasopharyngeal specimens entered the laboratory for Bordetella sp. PCR, of which 224 were positive. The analysis by Q-PCR directed to the recA gene of B. holmesii of all 224 positive samples determined a prevalence of B. holmesii of 0.6% (12/1994). Because of its more aggressive behavior in immunosupressed patients and its different resistance pattern, routine screening of B. pertussis and B. holmesii is currently performed for all samples in which Bordetella sp PCR is initially detected.


La incidencia de coqueluche en Chile varía entre 4,1 y 7,5 por 100.000 habitantes. La detección de Bordetella pertussis se realiza por RPC-tiempo real (Q-RPC) dirigida a la secuencia de inserción IS481. Sin embargo, esta secuencia se encuentra también en el genoma de B. bronchiseptica y B. holmesii. Este último es también un patógeno respiratorio que produce un cuadro similar a B. pertussis. Sin embargo, es importante diferenciar entre estas especies porque en pacientes inmunosuprimidos B. holmesii tiene mayor tendencia a causar bacteriemia y además es menos susceptible a eritromicina. El objetivo de este trabajo es determinar, prospectiva y retrospectivamente, la presencia de B. holmesii en muestras informadas positivas para B. pertussis en el período 2010-2011. Durante ese período ingresaron al laboratorio 1. 994 muestras de hisopado nasofaríngeo para RPC de Bordetella sp., de las cuales 224 fueron positivas. El análisis por Q-RPC dirigido al gen recA de B. holmesii de las 224 muestras positivas determinó una prevalencia de B. holmesii de 0,6% (12/1994). Debido al comportamiento más agresivo en inmunosuprimidos y al patrón de resistencia de B. holmesi, se decide incorporar la detección de rutina de B. pertussis y B. holmesii en todas las muestras en que se detecta inicialmente la presencia de Bordetella sp.


Assuntos
Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Bordetella/genética , DNA Bacteriano/análise , Coqueluche/epidemiologia , Coqueluche/microbiologia , Bordetella pertussis/genética , Chile/epidemiologia , Surtos de Doenças , Métodos Epidemiológicos , Extinção Biológica , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano , Análise de Sequência de DNA
12.
Biosci. j. (Online) ; 29(2): 408-411, mar./apr. 2013. graf, tab
Artigo em Português | LILACS | ID: biblio-914407

RESUMO

O Jacarandá da Bahia é uma espécie florestal nativa pertencente a família Leguminosaea Papilionoideae com ocorrência desde o sul da Bahia até o estado de São Paulo. O extrativismo e a pecuária contribuíram para a sua quase extinção e apesar disso, pouco tem sido feito para a multiplicação desta espécie. A micropropagação é uma alternativa para obtenção de grande quantidade de mudas sadias em curto espaço de tempo. Foram utilizados meristemas apicais e gemas axilares de plântulas de Jacarandá da Bahia, cultivadas em condições assépticas nos tratamentos compostos por meios de cultura (MS e WPM), concentrações de BAP (4, 9 e 18 µM) e com a ausência ou presença de agente antioxidante (PVP ou carvão ativado), totalizando 18 tratamentos, cada um com 10 repetições. As avaliações foram realizadas com 4 e 8 semanas de cultivo, considerando a porcentagem de explantes oxidados. Os meios de cultura de antioxidantes testados não diferiram estatisticamente entre si, porém tratamentos com BAP na concentração de 18 µM foram os que apresentaram maior oxidação.


Dalbergia nigra is a native forest species belonging the Papilionoideae-Leguminosaea family occurring from southern Bahia to the state of Sao Paulo. The extraction and livestock contributed to its near extinction and yet little has been done to the multiplication of this species. The micropropagation techniques are an alternative in order to achieve a large amount of seedlings in a short time and under conditions plant without diseases. Used apical and lateral meristems of Dalbergia nigra seedlings, grown in aseptic conditions in treatments consisting of different culture media (MS and WPM), BAP concentrations (4, 9 and 18 µM) and the absence or presence of antioxidant agent (PVP or activated charcoal), all crossed each other, totaling 18 treatments, each with 10 repetitions. Evaluations were performed at 4 and 8 weeks of cultivation, considering the percentage of browning explants. The culture media of antioxidants tested did not differ statistically, but BAP at a concentration of 18 µM were those with the highest oxidation.


Assuntos
Técnicas In Vitro , Meristema , Conservação dos Recursos Naturais , Dalbergia , Extinção Biológica , Antioxidantes
13.
Braz. j. biol ; 73(1): 91-101, Feb. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-671369

RESUMO

Grasslands are characteristic physiognomies of the Brazilian Cerrado domain. One of last remnants of these threatened environments in the state of São Paulo is located in Itirapina Ecological Station, considered as an Important Bird Area (IBA). We investigated bird assemblages that use seasonally flooded grasslands, and predominantly dry grasslands, from August 2010 until July 2011. We focused on aspects of assemblage structure, and possible responses of birds to environmental changes. We recorded 76 species, of which 23.7% are threatened. Some basic aspects of assemblages were similar between environments, such as diversity descriptors, and the tendency of increase richness in the same periods. Other parameters differed between environments, such as absolute richness, recorded monthly (lower in seasonally flooded grasslands). Considering time dimension in analyses, we observed differences in assemblage structure over time, within and between environments. When birds were grouped in guilds, assemblage structure did also differ. We identified significant correlations between the abundance of some guilds and environmental variables. Changes in the availability of resources and microhabitats may affect structure and organization of the studied bird assemblages.


Os campos são fisionomias características do domínio do Cerrado no Brasil. Um dos últimos remanescentes destes ambientes ameaçados no Estado de São Paulo está localizado na Estação Ecológica de Itirapina, a qual é considerada uma IBA (Important Bird Area). Foram investigadas as assembleias de aves que utilizaram os campos limpos sazonalmente alagáveis e os campos limpos predominantemente secos, de agosto de 2010 a julho de 2011. Neste estudo, focaram-se aspectos da estrutura das assembleias e possíveis respostas das aves às mudanças ambientais. Foram registradas 76 espécies, das quais 23,7% estão ameaçadas. Alguns aspectos básicos das assembleias foram similares entre os ambientes, como os descritores de diversidade e a tendência de aumento da riqueza durante os mesmos períodos; outros aspectos se distinguiram, como a riqueza absoluta registrada mensalmente (menor nos campos limpos sazonalmente alagáveis). Ao considerar-se a dimensão temporal nas análises, notam-se diferenças na estrutura ao longo do tempo, dentro e entre os ambientes. Quando as aves foram agrupadas em guildas, a estrutura das assembleias também se mostrou diferente. Identificaram-se correlações significativas entre a abundância de algumas guildas e as variáveis ambientais. Mudanças na disponibilidade de recursos e micro-habitats podem afetar a estrutura e a organização das assembleias das aves estudadas.


Assuntos
Animais , Aves/classificação , Estações do Ano , Brasil , Extinção Biológica , Densidade Demográfica , Dinâmica Populacional
14.
Rev. colomb. biotecnol ; 14(2): 28-37, dic. 2012. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-671878

RESUMO

Rhodogeron coronopifolius Griseb., es una especie vegetal de la familia Asteraceae, que se encuentra en peligro crítico de extinción. Es endémico de la provincia Villa Clara en la región central de Cuba. Habita en el matorral xeromorfo sub espinoso sobre serpentina. Existen solo cinco poblaciones naturales dentro de un área protegida, la principal causa de amenaza es la fragmentación de su hábitat por acciones antrópicas. Debido a su situación de conservación, se hace necesario realizar estudios de la diversidad genética de las poblaciones naturales para así generar información básica y diseñar una estrategia de conservación. El objetivo de este trabajo fue analizar de manera preliminar la diversidad genética de cuatro poblaciones de esta especie utilizando marcadores AFLP (Polimorfismo de Longitud de Fragmentos Amplificados). Se emplearon dos combinaciones de iniciadores y se evaluó el porcentaje de polimorfismo así como la similitud entre los individuos. Se obtuvieron 165 loci de los cuales el 78,7 % fueron polimórficos. La población de mayor polimorfismo fue Corojito con 85,2%, de manera general el polimorfismo fue alto con valores entre 75 y 87%. La similitud entre los individuos también fue alta con un promedio de 0,74. El agrupamiento genético fue independiente a la población de procedencia, lo que sugiere que existe intercambio genético entre las poblaciones y que estas comparten más del 80 % de los alelos que fueron analizados. Los resultados obtenidos son importantes para el mantenimiento in situ de la especie y para tomar decisiones en aras de su conservación.


Rhodogeron coronopifolius Griseb., is a specie of Asteraceae family, in critical danger of extinction. It is an endemic of Villa Clara city in the central region of Cuba. Its inhabits sub thorny xeromorphic heath on serpentine soil. Only five natural populations exist included in a protected area, the main threat cause is the fragmentation of its habitat for antropics activities. Due to their conservation status, it becomes necessary to analyze the genetic diversity of the natural populations in order to generate basic information usefull to apply a conservation strategy. The main goal of this work was to evaluate in a preliminary manner the genetic diversity of four populations of this specie using AFLP markers (Amplified Fragment Length Polymorphism). Two primer combinations were used and the polymorphism percentage was evaluated as well as the similarity among the individuals. A total of 165 loci were obtained of which 78,7% were polymorphic. The population with higher polymorphism was Corojito with 85,2%. High level of polymorphism was observed among population showing values between 75 and 87%. The similarity among the individuals was also high with an average of 0,74. The genetic grouping was independent to the origin of the population. This suggesting that gene flow exists among the populations, those which share more than 80% of the alleles analyzed. This is important for the in situ maintenance of the specie and to take decisions for their conservation.


Assuntos
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Asteraceae , Cuba , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Política Ambiental , Conservação dos Recursos Naturais , Extinção Biológica
15.
Rev. biol. trop ; 60(4): 1631-1639, Dec. 2012. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-662236

RESUMO

Black lechwe (Kobus leche smithemani) is a semi-aquatic medium sized antelope currently enlisted on the IUCN red list of endangered species and is only endemic to the Bangweulu basin of Zambia. Its population has significantly decreased due to floods that took place during the period 1930-1940 from over 250 000-15 000 leading the Zambian government to gazette all habitats of Black lechwe into state protected areas, and to establish urgent management strategies needed to save the remaining population from extinction. Using retrospective data, our findings show that the population has increased from 15 000 animals in 1954 to 55 632 in 2009. The current population is estimated at 34.77% (55 632/160 000) of the carrying capacity of the Bangweulu basin. Although the Black lechwe is one of the 42 species offered for consumptive utilization by the Zambia Wildlife Authority (ZAWA), only 0.12% and 0.08% of the current stock was offered for safari and resident hunting annually for the period 2005-2009, respectively. Annual quota utilization were estimated at 67% (n=37) and 81% (n=37) for safari and resident hunting, respectively. Hence, overall income obtained from utilization of Black lechwe is very low accounting for only 2.1% of the total revenue earned from wildlife utilization. Although the current population trend is showing a unit increase of 639 animals per year, it is still far below levels ideal for the lucrative utilization. In this study, we demonstrate that adverse ecological changes on wildlife species, can lead to their vulnerability and danger of extinction, and that their recovery to full carrying capacity may demand a considerable amount of time.


El lechwe negro (Kobus leche smithemani) es un antílope semi-acuático de tamaño medio que en la actualidad se encuentra en la lista roja de la UICN de especies en peligro de extinción y sólo es endémica de la cuenca del Bangweulu de Zambia. Su población ha disminuido considerablemente, de más de 250 000 a 15 000, debido a las inundaciones que se dieron durante el período 1930-1940, lo que llevó al gobierno de Zambia a declarar todos los hábitats del lechwe negro en áreas protegidas estatales, y a establecer estrategias de administración urgentes necesarias para salvar el resto de la población de la extinción. Utilizando los datos retrospectivos, nuestros resultados muestran que la población ha aumentado de 15 000 animales en 1954 a 55 632 en 2009. La población actual se estima en 34.77% (55 632/160 000) de la capacidad de carga de la cuenca del Bangweulu. Aunque el lechwe Negro es una de las 42 especies que se ofrecen para su utilización consuntiva por la Autoridad de Vida Silvestre de Zambia (ZAWA), sólo el 0.12% y 0.08% de la población actual se ha ofrecido para el safari y la caza residente anual para el período 2005-2009, respectivamente. La utilización de la cuota anual se estima en 67% (n=67) y 81% (n=37) para safari de caza y residente, respectivamente. Por lo tanto, los ingresos totales obtenidos de la utilización del lechwe negro son muy bajos contando sólo el 2.1% de los ingresos totales obtenidos de la utilización de la fauna silvestre. Aunque la tendencia actual de la población está mostrando un incremento unitario de 639 animales por año, está todavía muy por debajo de los niveles ideales para la utilización lucrativa. En este estudio, se demuestra que los cambios ecológicos perjudiciales sobre especies de fauna silvestre, puede conducir a su vulnerabilidad y peligro de extinción, y que la recuperación de su capacidad de carga completa puede exigir una cantidad considerable de tiempo.


Assuntos
Animais , Antílopes/classificação , Ecossistema , Espécies em Perigo de Extinção , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Monitoramento Ambiental , Extinção Biológica , Densidade Demográfica , Zâmbia
16.
Acta sci., Biol. sci ; 34(4): 429-436, Oct.-Dec. 2012. mapas, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-859676

RESUMO

The Antillean manatee (Trichechus manatus) is the most threatened aquatic mammal in Brazil. It was considered to be extinct in Sergipe until 1998, when a re-introduced animal (Astro) arrived. Given plans for the re -introduction of more animals, a survey was conducted of the waterside communities of the animal's home range, on the southern coast of Sergipe. Between March and November, 2009, 27 people were interviewed in 12 communities, using a 14- item questionnaire. All the interviewees knew Astro and were familiar with his behaviour. The primary source of tension between the animal and the community is its habit of approaching vessels and, in particular, fishing equipment. Some fishermen reported that he takes fish from their nets. While most local residents are tolerant of the animal's presence, some interviewees reported aggression in the context of fishing. Most of the interviewees agreed with the idea of re -introducing more animals locally, but conflicts related to fishing were seen as the main potential problem. Given this, there is a clear need for a comprehensive environmental education programme, in order to guarantee the conservation of the species in the region.


O peixe-boi marinho (Trichechus manatus) é o mamífero aquático mais ameaçado no Brasil. Era considerado extinto em Sergipe até 1998, quando chegou um animal reintroduzido (Astro). Visando a eventual reintrodução de mais animais, foi realizado um levantamento de comunidades ribeirinhas de sua área de vida, no litoral Sul de Sergipe. Entre março e novembro de 2009, 27 pessoas foram entrevistadas em 12 comunidades, usando um questionário com 14 perguntas. Todos os entrevistados conheciam o Astro e tinham alguma noção de seu comportamento. A fonte principal de atrito entre o animal e a comunidade é seu hábito de se aproximar de embarcações e, principalmente, de equipamentos de pesca. Alguns pescadores relataram que o animal retira peixes de suas redes. Apesar da tolerância geral em relação à presença do animal, alguns entrevistados relataram agressões no contexto da pesca. A maioria dos entrevistados foi acessível à ideia de reintroduzir mais animais na região, embora o atrito em relação à pesca se destacou como o maior problema em potencial. Assim, ficou clara a necessidade de um programa abrangente de conscientização ambiental, para garantir a conservação da espécie na região.


Assuntos
Animais , Características de Residência , Conservação dos Recursos Naturais , Trichechus inunguis , Extinção Biológica
17.
An. acad. bras. ciênc ; 83(2): 483-511, June 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-589910

RESUMO

Enchodontoidei are extinct marine teleost fishes with a long temporal range and a wide geographic distribution. As there has been no comprehensive phylogenetic study of this taxon, we performed a parsimony analysis using a data matrix with 87 characters, 31 terminal taxa for ingroup, and three taxa for outgroup. The analysis produced 93 equally parsimonious trees (L = 437 steps; CI = 0. 24; RI = 0. 49). The topology of the majority rule consensus tree was: (Sardinioides + Hemisaurida + (Nardorex + (Atolvorator + (Protostomias + Yabrudichthys ) + (Apateopholis + (Serrilepis + (Halec + Phylactocephalus ) + (Cimolichthys + (Prionolepis + ( (Eurypholis + Saurorhamphus ) + (Enchodus + (Paleolycus + Parenchodus ))))))) + ( (Ichthyotringa + Apateodus ) + (Rharbichthys + (Trachinocephalus + ( (Apuliadercetis + Brazilodercetis ) + (Benthesikyme + (Cyranichthys + Robertichthys ) + (Dercetis + Ophidercetis )) + (Caudadercetis + (Pelargorhynchus + (Nardodercetis + (Rhynchodercetis + (Dercetoides + Hastichthys )))))). The group Enchodontoidei is not monophyletic. Dercetidae form a clade supported by the presence of very reduced neural spines and possess a new composition. Enchodontidae are monophyletic by the presence of middorsal scutes, and Rharbichthys was excluded. Halecidae possess a new composition, with the exclusion of Hemisaurida. This taxon and Nardorex are Aulopiformes incertae sedis.


Os Enchodontoidei são peixes teleósteos marinhos extintos, com uma longa amplitude temporal e uma ampla distribuição geográfica. Tendo em vista que não há nenhuma proposta ampla para a filogenia deste táxon, foi realizada uma aná lise de parcimônia com base numa matriz de dados de 87 caracteres, 31 táxons terminais no grupo interno, e três táxons no grupo externo. Como resultado da análise, foram obtidas 93 árvores igualmente parcimoniosas (L = 437 passos; CI = 0,24; RI = 0,49). O consenso de maioria é representado pela seguinte topologia: (Sardinioides + Hemisaurida + (Nardorex + (Atolvorator + (Protostomias + Yabrudichthys ) + (Apateopholis + (Serrilepis + (Halec + Phylactocephalus ) + (Cimolichthys + (Prionolepis + ( (Eurypholis + Saurorhamphus ) + (Enchodus + (Paleolycus + Parenchodus ))))))) + ( (Ichthyotringa + Apateodus ) + (Rharbichthys + (Trachinocephalus + ( (Apuliadercetis + Brazilodercetis ) + (Benthesikyme + (Cyranichthys + Robertichthys ) + (Dercetis + Ophidercetis )) + (Caudadercetis + (Pelargorhynchus + (Nardodercetis + (Rhynchodercetis + (Dercetoides + Hastichthys )))))). O grupo Enchodontoidei não é monofilético. Os Dercetidae formam um clado suportado pela presença de espinhos neurais muito reduzidos e possuem uma nova composição. Os Enchodontidae são um grupo monofilético, devido à presença de escudos no dorso, e Rharbichthys foi excluído do clado. Os Halecidae possuem uma nova composição, com a exclusão de Hemisaurida. Este táxon e Nardorex são Aulopiformes incertae sedis.


Assuntos
Animais , Extinção Biológica , Peixes/classificação , Classificação/métodos , Filogenia
18.
Journal of the Korean Medical Association ; : 149-155, 2011.
Artigo em Coreano | WPRIM | ID: wpr-37690

RESUMO

Climactic changes, especially global warming, are potentially the largest global threat to human health and the source of the greatest number of cases of disease. If current emissions and land use trends continue unchecked, future generations will face more serious conditions, including injury, disease, and death related to natural disasters and heat waves, higher rates of climate-related infections, widespread malnutrition, and more allergy and air pollutionrelated morbidity and mortality. This review highlights the relationship between global climate changes and human health and provides some suggestions for improvement. According to the Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC) published in 2007, global warming is caused by greenhouse gas (GHG) emissions. The most important GHG is carbon dioxide (CO2), which is released by the burning of fossil fuels and, to a lesser extent, by land use practices, followed by nitrous oxide and methane. IPCC predicts that global temperatures will rise 1.8degrees C-4.0degrees C by 2099. According to the report, we can expect a significant rise in sea levels, massive species extinctions, changes in storm and drought cycles, altered ocean circulation, and redistribution of vegetation after crossing the "tipping point" of global warming. Human health will be adversely affected by the accelerating climate change. This review stimulates health care providers to provide quality care to susceptible individuals confronting new threats from climactic changes, as well as to work toward a mitigation of the drivers of climate change at the individual, community, and policy levels as part of a long-term commitment to protecting public health.


Assuntos
Humanos , Queimaduras , Dióxido de Carbono , Clima , Mudança Climática , Desastres , Secas , Extinção Biológica , Combustíveis Fósseis , Aquecimento Global , Pessoal de Saúde , Hipersensibilidade , Raios Infravermelhos , Desnutrição , Metano , Óxido Nitroso , Saúde Pública , Responsabilidade Social
19.
Journal of the Korean Medical Association ; : 175-180, 2011.
Artigo em Coreano | WPRIM | ID: wpr-37686

RESUMO

The average temperature of the Earth's near-surface air and the oceans has increased 0.74 +/- 0.18degrees C over the last century. Climate change can cause sea levels to rise, change the amount and pattern of precipitation, shrink the cover of rain forest and forest, increase the intensity of extreme weather events, and cause species extinctions and changes in agricultural yields. Many human diseases, such as cardiovascular diseases, allergies, respiratory diseases, and infectious diseases, are related to climate fluctuation. Climate change can cause the level of air pollutants to increase and affect the interaction of air pollutants and respiratory allergens. Ambient air pollutants such as nitrogen dioxide, ozone, particulate matter, volatile organic compounds, and sulfur dioxide have been linked to allergic diseases and asthma. Here, the effect of climate change and air pollution on health outcomes such as asthma and allergic diseases is reviewed.


Assuntos
Humanos , Poluentes Atmosféricos , Poluição do Ar , Alérgenos , Asma , Doenças Cardiovasculares , Clima , Mudança Climática , Doenças Transmissíveis , Extinção Biológica , Hipersensibilidade , Dióxido de Nitrogênio , Oceanos e Mares , Ozônio , Material Particulado , Chuva , Dióxido de Enxofre , Compostos Orgânicos Voláteis , Tempo (Meteorologia)
20.
Rev. biol. trop ; 58(4): 1115-1126, dic. 2010. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-637986

RESUMO

Human activity is leading to mass species extinctions worldwide. Conservation biology (CB) courses, taught worldwide at universities, typically focus on the proximal causes of extinction without teaching students how to respond to this crisis. The Extinction of Species 360 course has been taught yearly each fall semester to several hundred students at the University of Wisconsin-Madison for over two decades. In 2007 the instructor and five teaching assistants combined principles driving extinctions, based on traditional lectures and discussion sections, with action-oriented education targeting individual consumer habits, to a group of 285 students. Students learn the science underpinning conservation efforts, as evidenced by highly significant learning (<.001) gains in a 22 question survey in every measured category, and also make direct and immediate changes in their lifestyle and consumption habits. This course succeeded in each of its three primary goals: a) informed students about the value of and threats to biodiversity, similar to traditional CB courses, b) emphasized our personal role (as consumers) in perpetuating the extinction crisis and c) facilitated activities to reduce our impact and help alleviate the crisis. The results suggested students learned CB concepts and understood biodiversity’s value, increased their awareness of the connection between personal consumption and extinction, and reduced their collective ecological footprints. Furthermore, students complemented their learning and multiplied the potential for consumption reduction, by participating in action-based activities. Such academic courses can provide a rigorous treatment of the direct and indirect causes of extinction while developing a student’s sense of personal empowerment to help slow the extinction crisis. Rev. Biol. Trop. 58 (4): 1115-1126. Epub 2010 December 01.


La actividad humana está produciendo grandes extinciones de especies en todo el mundo. Los cursos de biología de la conservación (BC), impartidos en universidades de todo el mundo, por lo general se enfocan en las causas de la extinción, sin enseñar a los estudiantes cómo responder a esta crisis. Durante más de dos décadas, la Universidad de Wisconsin-Madison ha ofrecido el curso Extinción de las Especies (#360), que se ha dado cada año, durante otoño a varios cientos de estudiantes cada vez. En 2007 el instructor y cinco asistentes de enseñanza combinaron los principios de manejo de la extinción, con base en presentaciones tradicionales y una sección de discusión, con educación con acción-orientada a los hábitos individuales de consumo, a un grupo de 285 estudiantes. Ellos aprendieron que la ciencia sustenta los esfuerzos de conservación, como lo demuestra el aprendizaje altamente significativo (P<.001) en una encuesta de 22 preguntas en todas las categorías medidas, y en cambios directos e inmediatos en su estilo de vida y hábitos de consumo. Este curso tuvo éxito en cada uno de sus tres objetivos principales: a) los estudiantes fueron informados sobre el valor y las amenazas a la biodiversidad, similar a los tradicionales cursos de BC, b) hizo hincapié en nuestro papel personal (como consumidores) en perpetuar la crisis de la extinción y c) facilito actividades para reducir nuestro impacto y ayudar a disminuir la crisis. Los resultados sugieren que los estudiantes aprendieron conceptos de CB y comprendieron el valor de la biodiversidad, aumentaron su preocupación por la conexión entre el consumo personal y la extinción, y redujeron la huella ecológica colectiva. Además, los estudiantes complementaron su aprendizaje y se multiplicó el potencial de reducción del consumo, mediante la participación en actividades basado en acciones concretos. Estos cursos académicos pueden proporcionar un tratamiento riguroso de las causas directas e indirectas de la extinción, al mismo tiempo que desarrollar en el estudiante el sentido de poder personal para ayudar a disminuir la crisis de la extinción.


Assuntos
Humanos , Biologia/educação , Extinção Biológica , Ensino/métodos , Conservação dos Recursos Naturais/métodos , Estudantes , Universidades
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