Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.675
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 120(28): e2301338120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37399374

RESUMO

Recent fossil discoveries in Western Amazonia revealed that two distinct anthropoid primate clades of African origin colonized South America near the Eocene/Oligocene transition (ca. 34 Ma). Here, we describe a diminutive fossil primate from Brazilian Amazonia and suggest that, surprisingly, a third clade of anthropoids was involved in the Paleogene colonization of South America by primates. This new taxon, Ashaninkacebus simpsoni gen. et sp. nov., has strong dental affinities with Asian African stem anthropoids: the Eosimiiformes. Morphology-based phylogenetic analyses of early Old World anthropoids and extinct and extant New World monkeys (platyrrhines) support relationships of both Ashaninkacebus and Amamria (late middle Eocene, North Africa) to the South Asian Eosimiidae. Afro-Arabia, then a mega island, played the role of a biogeographic stopover between South Asia and South America for anthropoid primates and hystricognathous rodents. The earliest primates from South America bear little adaptive resemblance to later Oligocene-early Miocene platyrrhine monkeys, and the scarcity of available paleontological data precludes elucidating firmly their affinities with or within Platyrrhini. Nonetheless, these data shed light on some of their life history traits, revealing a particularly small body size and a diet consisting primarily of insects and possibly fruit, which would have increased their chances of survival on a natural floating island during this extraordinary over-water trip to South America from Africa. Divergence-time estimates between Old and New World taxa indicate that the transatlantic dispersal(s) could source in the intense flooding events associated with the late middle Eocene climatic optimum (ca. 40.5 Ma) in Western Africa.


Assuntos
Cebidae , Platirrinos , Animais , Filogenia , Brasil , Haplorrinos , Fósseis , Roedores , Evolução Biológica
2.
Proc Natl Acad Sci U S A ; 119(40): e2116446119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36161957

RESUMO

Monitoring the status of species is crucial for biodiversity conservation and sustainable resource management in tropical forests, but conventional in situ monitoring methods are impractical over large scales. Scientists have resorted to two potentially complementary approaches: local ecological knowledge (LEK) and remote sensing. To gauge the potential of combining LEK and remote sensing for assessing species status at landscape scales, a large-scale assessment of the reliability of both measures is critical but hampered by the lack of ground-level data. We conducted a landscape-scale assessment of LEK and remote sensing, using a survey of over 900 communities (a near census in our study area) and nearly 4,000 households in 235 randomly selected communities in the Peruvian Amazon-the largest LEK survey as yet undertaken in tropical forests. The survey collected LEK data on the presence of 20 indicator species from both community leaders/elders and randomly sampled households. We assessed LEK and remotely sensed land cover-forest cover and nonmain channel open water-as proxies for species habitat, across species (game, fish, and timber), over time (current and historical), and by indigeneity (Indigenous peoples and mestizos). Overall, LEK and remotely sensed land cover corroborate each other well. Concordance is highest for the current status of game species reported by sampled households, as is the concordance of historical LEK from Indigenous community leaders/elders. The results point to the promise of combining LEK and remote sensing in monitoring the status of species in data-poor tropical forests.


Assuntos
Florestas , Tecnologia de Sensoriamento Remoto , Animais , Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Peru , Reprodutibilidade dos Testes , Clima Tropical , Água
3.
Emerg Infect Dis ; 30(8): 1545-1554, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39043387

RESUMO

Human infections with Corynebacterium diphtheriae species complex (CdSC) bacteria were rare in French Guiana until 2016, when the number of cases diagnosed increased. We conducted an epidemiologic, multicenter, retrospective study of all human CdSC infections diagnosed in French Guiana during January 1, 2016-December 31, 2021. A total of 64 infectious episodes were observed in 60 patients; 61 infections were caused by C. diphtheriae and 3 by C. ulcerans. Estimated incidence increased from 0.7 cases/100,000 population in 2016 to 7.7 cases/100,000 population in 2021. The mean patient age was 30.4 (+23.7) years, and male-to-female ratio was 1.7:1 (38/22). Of the 61 C. diphtheriae isolates, 5 tested positive for the diphtheria toxin gene, and all results were negative by Elek test; 95% (61/64) of cases were cutaneous, including the C. ulcerans cases. The increase in reported human infections underscores the need to raise awareness among frontline healthcare practitioners to improve prevention.


Assuntos
Corynebacterium diphtheriae , Difteria , Humanos , Guiana Francesa/epidemiologia , Estudos Retrospectivos , Feminino , Masculino , Corynebacterium diphtheriae/isolamento & purificação , Corynebacterium diphtheriae/genética , Adulto , Pessoa de Meia-Idade , Adolescente , Criança , Adulto Jovem , Pré-Escolar , Difteria/epidemiologia , Difteria/microbiologia , Idoso , Incidência , Lactente , História do Século XXI , Infecções por Corynebacterium/epidemiologia , Infecções por Corynebacterium/microbiologia
4.
New Phytol ; 241(3): 1035-1046, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37984822

RESUMO

Climate models predict that everwet western Amazonian forests will face warmer and wetter atmospheric conditions, and increased cloud cover. It remains unclear how these changes will impact plant reproductive performance, such as flowering, which plays a central role in sustaining food webs and forest regeneration. Warmer and wetter nights may cause reduced flower production, via increased dark respiration rates or alteration in the reliability of flowering cue-based processes. Additionally, more persistent cloud cover should reduce the amounts of solar irradiance, which could limit flower production. We tested whether interannual variation in flower production has changed in response to fluctuations in irradiance, rainfall, temperature, and relative humidity over 18 yrs in an everwet forest in Ecuador. Analyses of 184 plant species showed that flower production declined as nighttime temperature and relative humidity increased, suggesting that warmer nights and greater atmospheric water saturation negatively impacted reproduction. Species varied in their flowering responses to climatic variables but this variation was not explained by life form or phylogeny. Our results shed light on how plant communities will respond to climatic changes in this everwet region, in which the impacts of these changes have been poorly studied compared with more seasonal Neotropical areas.


Assuntos
Árvores , Clima Tropical , Árvores/fisiologia , Reprodutibilidade dos Testes , Florestas , Plantas , Mudança Climática , Flores/fisiologia
5.
Mol Phylogenet Evol ; 191: 107971, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38000706

RESUMO

The iconic mountains of the Pantepui biogeographical region host many early-diverging endemic animal and plant lineages, concurring with Conan Doyle's novel about an ancient "Lost World". While this is the case of several frog lineages, others appear to have more recent origins, adding to the controversy around the diversification processes in this region. Due to its remoteness, Pantepui is challenging for biological surveys, and only a glimpse of its biodiversity has been described, which hampers comprehensive evolutionary studies in many groups. During a recent expedition to the Neblina massif on the Brazil-Venezuela border, we sampled two new frog species that could not be assigned to any known genus. Here, we perform phylogenetic analyses of mitogenomic and nuclear loci to infer the evolutionary relationships of the new taxa and support their description. We find that both species represent single lineages deeply nested within Brachycephaloidea, a major Neotropical clade of direct-developing frogs. Both species diverged >45 Ma from their closest relatives: the first is sister to all other Brachycephaloidea except for Ceuthomantis, another Pantepui endemic, and the second is sister to Brachycephalidae, endemic to the Brazilian Atlantic Forest. In addition to these considerable phylogenetic and biogeographic divergences, external morphology and osteological features support the proposition of two new family and genus-level taxa to accommodate these new branches of the amphibian tree of life. These findings add to other recently described ancient vertebrate lineages from the Neblina massif, providing a bewildering reminder that our perception of the Pantepui's biodiversity remains vastly incomplete. It also provides insights into how these mountains acted as "museums" during the diversification of Brachycephaloidea and of Neotropical biotas more broadly, in line with the influential "Plateau theory". Finally, these discoveries point at the yet unknown branches of the tree of life that may go extinct, due to global climate change and zoonotic diseases, before we even learn about their existence, amphibians living at higher elevations being particularly at risk.


Assuntos
Anuros , Museus , Animais , Filogenia , Anuros/genética , Biodiversidade , Evolução Biológica
6.
Mol Phylogenet Evol ; 192: 108008, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38181828

RESUMO

Two main landscapes emerge from the Guiana Shield: the highlands to the west called the Pantepui region and the Amazonian lowlands to the east, both harbouring numerous endemic species. With 32 currently recognized species, the genus Anomaloglossus stands out among Neotropical frogs as one that diversified only within the Guiana Shield both in the highlands and the lowlands. We present a time-calibrated phylogeny obtained by using combined mitogenomic and nuclear DNA, which suggests that the genus originates from Pantepui where extant lineages started diversifying around 21 Ma, and subsequently (ca. 17 Ma) dispersed during the Miocene Climatic Optimum to the lowlands of the eastern Guiana Shield where the ability to produce endotrophic tadpoles evolved. Further diversification within the lowlands in the A. stepheni group notably led to an evolutionary reversal toward exotrophy in one species group during the late Miocene, followed by reacquisition of endotrophy during the Pleistocene. These successive shifts of reproductive mode seem to have accompanied climatic oscillations. Long dry periods might have triggered evolution of exotrophy, whereas wetter climates favoured endotrophic forms, enabling colonization of terrestrial habitats distant from water. Acquisition, loss, and reacquisition of endotrophy makes Anomaloglossus unique among frogs and may largely explain the current species diversity. The micro evolutionary processes involved in these rapid shifts of reproductive mode remain to be revealed.


Assuntos
Anuros , Ecossistema , Animais , Anuros/genética , Filogenia , Filogeografia
7.
Mol Phylogenet Evol ; 190: 107959, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918682

RESUMO

Despite their limited vagility and pronounced habitat heterogeneity in the tropics, many anuran species have unexpectedly extensive geographic ranges. One prominent example of this phenomenon is Pithecopus hypochondrialis, which is found in the Cerrado, Guianan savanna, and Llanos domains, as well as isolated tracts of savanna and open habitat within the Amazon Forest. The present study employs an integrative species delimitation approach to test the hypothesis that P. hypochondrialis is in fact a species complex. We also reconstruct the relationships among the lineages delimited here and other Pithecopus species. In this study, we employ Ecological Niche Modelling (ENM) and spatiotemporal phylogeographic reconstruction approaches to evaluate a multitude of scenarios of connectivity across the Neotropical savannas. We identified three divergent lineages, two of which have been described previously. The lineages were allocated to a lowland Pithecopus clade, although the relationships among these lineages are weakly supported. Both the ENM and the phylogeographic reconstruction highlight the occurrence of periods of connectivity among the Neotropical savannas over the course of the Pliocene and Pleistocene epochs. These processes extended from eastern Amazonia to the northern coast of Brazil. The findings of the present study highlight the presence of hidden diversity within P. hypochondrialis, and reinforce the need for a comprehensive taxonomic review. These findings also indicate intricate and highly dynamic patterns of connectivity across the Neotropical savannas that date back to the Pliocene.


Assuntos
Ecossistema , Pradaria , Animais , Filogeografia , Filogenia , Anuros/genética
8.
Syst Biol ; 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37804132

RESUMO

Can knowledge about genome architecture inform biogeographic and phylogenetic inference? Selection, drift, recombination, and gene flow interact to produce a genomic landscape of divergence wherein patterns of differentiation and genealogy vary nonrandomly across the genomes of diverging populations. For instance, genealogical patterns that arise due to gene flow should be more likely to occur on smaller chromosomes, which experience high recombination, whereas those tracking histories of geographic isolation (reduced gene flow caused by a barrier) and divergence should be more likely to occur on larger and sex chromosomes. In Amazonia, populations of many bird species diverge and introgress across rivers, resulting in reticulated genomic signals. Herein, we used reduced representation genomic data to disentangle the evolutionary history of four populations of an Amazonian antbird, Thamnophilus aethiops, whose biogeographic history was associated with the dynamic evolution of the Madeira River Basin. Specifically, we evaluate whether a large river capture event ca. 200 Ka, gave rise to reticulated genealogies in the genome by making spatially explicit predictions about isolation and gene flow based on knowledge about genomic processes. We first estimated chromosome-level phylogenies and recovered two primary topologies across the genome. The first topology (T1) was most consistent with predictions about population divergence and was recovered for the Z chromosome. The second (T2), was consistent with predictions about gene flow upon secondary contact. To evaluate support for these topologies, we trained a convolutional neural network to classify our data into alternative diversification models and estimate demographic parameters. The best-fit model was concordant with T1 and included gene flow between non-sister taxa. Finally, we modeled levels of divergence and introgression as functions of chromosome length and found that smaller chromosomes experienced higher gene flow. Given that (1) gene-trees supporting T2 were more likely to occur on smaller chromosomes and (2) we found lower levels of introgression on larger chromosomes (and especially the Z-chromosome), we argue that T1 represents the history of population divergence across rivers and T2 the history of secondary contact due to barrier loss. Our results suggest that a significant portion of genomic heterogeneity arises due to extrinsic biogeographic processes such as river capture interacting with intrinsic processes associated with genome architecture. Future phylogeographic studies would benefit from accounting for genomic processes, as different parts of the genome reveal contrasting, albeit complementary histories, all of which are relevant for disentangling the intricate geogenomic mechanisms of biotic diversification.

9.
Eur J Clin Microbiol Infect Dis ; 43(6): 1081-1090, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38573394

RESUMO

PURPOSE: Over the past decade, the Amazon basin has faced numerous infectious epidemics. Our comprehension of the actual extent of these infections during pregnancy remains limited. This study aimed to clarify the clinical and epidemiological features of emerging and re-emerging infectious diseases during pregnancy in western French Guiana and along the Maroni River over the previous nine years. METHODS: This retrospective cohort study enrolled pregnant women living in west French Guiana territory and giving birth in the only local referral center after 22 weeks of gestation between 2013 and 2021. Data on symptomatic or asymptomatic biologically confirmed emerging or re-emerging diseases during pregnancy was collected. RESULTS: Six epidemic waves were experienced during the study period, including 498 confirmed Zika virus infections (2016), 363 SARS-CoV-2 infections (2020-2021), 87 chikungunya virus infections (2014), 76 syphilis infections (2013-2021), and 60 dengue virus infections (2013-2021) at different gestational ages. Furthermore, 1.1% (n = 287) and 1.4% (n = 350) of pregnant women in west French Guiana were living with HIV and HTLV, respectively. During the study period, at least 5.5% (n = 1,371) faced an emerging or re-emerging infection during pregnancy. CONCLUSION: These results highlight the diversity, abundance, and dynamism of emerging and re-emerging infectious agents faced by pregnant women in the Amazon basin. Considering the maternal and neonatal adverse outcomes associated with these infections, increased efforts are required to enhance diagnosis, reporting, and treatment of these conditions.


Assuntos
COVID-19 , Febre de Chikungunya , Doenças Transmissíveis Emergentes , Complicações Infecciosas na Gravidez , Infecção por Zika virus , Humanos , Feminino , Guiana Francesa/epidemiologia , Gravidez , Estudos Retrospectivos , Doenças Transmissíveis Emergentes/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/virologia , Adulto , Infecção por Zika virus/epidemiologia , Febre de Chikungunya/epidemiologia , COVID-19/epidemiologia , Adulto Jovem , Dengue/epidemiologia , Sífilis/epidemiologia , Infecções por HIV/epidemiologia
10.
Conserv Biol ; 38(4): e14245, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38456548

RESUMO

Understanding which species will be extirpated in the aftermath of large-scale human disturbance is critical to mitigating biodiversity loss, particularly in hyperdiverse tropical biomes. Deforestation is the strongest driver of contemporary local extinctions in tropical forests but may occur at different tempos. The 2 most extensive tropical forest biomes in South America-the Atlantic Forest and the Amazon-have experienced historically divergent pathways of habitat loss and biodiversity decay, providing a unique case study to investigate rates of local species persistence on a single continent. We quantified medium- to large-bodied mammal species persistence across these biomes to elucidate how landscape configuration affects their persistence and associated ecological functions. We collected occurrence data for 617 assemblages of medium- to large-bodied mammal species (>1 kg) in the Atlantic Forest and the Amazon. Analyzing natural habitat cover based on satellite data (1985-2022), we employed descriptive statistics and generalized linear models (GLMs) to investigate ecospecies occurrence patterns in relation to habitat cover across the landscapes. The subregional erosion of Amazonian mammal assemblage diversity since the 1970s mirrors that observed since the colonial conquest of the Atlantic Forest, given that 52.8% of all Amazonian mammals are now on a similar trajectory. Four out of 5 large mammals in the Atlantic Forest were prone to extirpation, whereas 53% of Amazonian mammals were vulnerable to extirpation. Greater natural habitat cover increased the persistence likelihood of ecospecies in both biomes. These trends reflected a median local species loss 63.9% higher in the Atlantic Forest than in the Amazon, which appears to be moving toward a turning point of forest habitat loss and degradation. The contrasting trajectories of species persistence in the Amazon and Atlantic Forest domains underscore the importance of considering historical habitat loss pathways and regional biodiversity erosion in conservation strategies. By focusing on landscape configuration and identifying essential ecological functions associated with large vertebrate species, conservation planning and management practices can be better informed.


Uso de la pérdida histórica de hábitat para predecir la desaparición de mamíferos contemporáneos en los bosques neotropicales Resumen Tener conocimiento de cuáles especies desaparecerán después de una perturbación humana es de suma importancia para mitigar la pérdida de la biodiversidad, particularmente en los biomas híper diversos. La deforestación es la principal causante de las extinciones locales contemporáneas en los bosques tropicales, aunque puede ocurrir en diferentes tiempos. Los dos bosques tropicales más extensos de América del Sur ­ el Bosque Atlántico y la Amazonia ­ han experimentado formas históricamente divergentes de pérdida de hábitat y decadencia de biodiversidad, lo que proporciona un caso único de estudio para investigar las tasas de persistencia de las especies locales en un solo continente. Cuantificamos la persistencia de las especies de mamíferos de talla mediana a grande en estos dos bosques para aclarar cómo la configuración del paisaje afecta su persistencia y las funciones ecológicas asociadas. Recolectamos datos de presencia de 617 ensambles de especies de mamíferos de talla mediana a grande (>1 kg) en el Bosque Atlántico y en la Amazonia. Analizamos la cobertura natural del hábitat con base en datos satelitales (1985­2022) y empleamos estadística descriptiva y modelos lineales generalizados (MLG) para investigar los patrones de presencia de las eco especies en relación con la cobertura del hábitat en los distintos paisajes. La erosión subregional de la diversidad de ensambles de mamíferos en la Amazonia desde los 70s es igual a la observada en el Bosque Atlántico desde la conquista colonial, dado que 52.8% de todos los mamíferos amazónicos se encuentran en una trayectoria similar. Cuatro de los cinco grandes mamíferos en el Bosque Atlántico estaban propensos a desaparecer, mientras que el 53% de los mamíferos amazónicos estaban vulnerables a desaparecer. Una mayor cobertura natural del hábitat incrementó la probabilidad de persistencia de las eco especies en ambos bosques. Estas tendencias reflejaron una pérdida mediana de especies locales 63.9% mayor en el Bosque Atlántico que en la Amazonia, lo cual parece dirigirse hacia un momento decisivo para la degradación y pérdida del hábitat del bosque. Las trayectorias contrastantes de la persistencia de especies en el Bosque Atlántico y la Amazonia destacan la importancia de considerar dentro de las estrategias de conservación las maneras en las que se ha perdido históricamente el hábitat y la erosión de la biodiversidad regional. Si nos enfocamos en la configuración del paisaje y en la identificación de las funciones ecológicas esenciales asociadas con las especies grandes de vertebrados, podemos informar de mejor manera a la planeación de la conservación y las prácticas de manejo.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Extinção Biológica , Florestas , Mamíferos , Animais , Mamíferos/fisiologia , Clima Tropical , Ecossistema , Brasil
11.
Philos Trans A Math Phys Eng Sci ; 382(2269): 20230065, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342214

RESUMO

The Amazon is the largest drainage basin on Earth and contains a wide variety of abiotic landscape features. In spite of this, the geodiversity in this basin has not yet been objectively evaluated. We address this knowledge gap by combining a meta-analysis of an existing global geodiversity map and its components with a systematic literature review, to identify the key characteristics of geodiversity in the Amazon drainage basin (ADB). We also evaluate how these global geodiversity component maps, that are based on the geology, geomorphology, soils and hydrology, could be refined to better reflect geodiversity in the basin. Our review shows that geology-through lithological diversity and geological structures-and hydrology-through hydrological processes that influence geomorphology and soil diversity-are the main determinants of geodiversity. Based on these features, the ADB can be subdivided into three principal regions: (i) the Andean orogenic belt and western Amazon, (ii) the cratons and eastern Amazon, and (iii) the Solimões-Amazon river system. Additional methods to map geomorphological and hydrological diversity have been identified. Future research should focus on investigating the relationship between the geodiversity components and assess their relationship with biodiversity. Such knowledge can enhance conservation plans for the ADB. This article is part of the Theo Murphy meeting issue 'Geodiversity for science and society'.

12.
Environ Res ; 252(Pt 3): 119027, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38697597

RESUMO

In Brazil, the favorable weather conditions and abundant land contribute to the thriving agricultural production. Brazilian crops extensively employ pesticides due to their high efficacy, cost-effectiveness, and permissive regulatory framework. However, pesticide use also endangers water resources, animal organisms, and human health. Due to the lack of data on pesticide use in the Amazonas forest-based Brazil, the present study aimed to assess the levels of twenty-one current-use pesticides (CUPs) from five different classes in river waters collected from urban and riverside areas in this region. Moreover, the non-carcinogenic risks associated with water consumption were also characterized. Thirteen CUPs were detected in concentrations above the limit of detection (LOD) in at least one of the water samples, and most pesticides were detected in riverside areas. In contrast, only 18% of the analyzed samples were considered "clean," with only one compound detected. Fenitrothion showed the highest concentration, with a mean value of 4.86 ng/mL (0.30-14.3 ng/mL). Up to 33% of the samples showed levels of fipronil above the LOD, an issue of environmental and human health concern, mainly because of the adverse effects observed in honeybees. Despite this, the human health risk assessment showed a target hazard quotient below one (HQ < 1) in adults for all substances, suggesting that pesticide exposure through water consumption should not mean risk for the riverside populations. Taking into account the large extension of Brazil, as well as its different agricultural practices throughout the country, it would be of great importance to conduct extensive research in other areas. It would help to gain knowledge in this field and to promote eco-friendly alternatives to mitigate pesticide use and, consequently, to reduce their potential adverse effects on human health and the ecosystems.


Assuntos
Monitoramento Ambiental , Praguicidas , Rios , Poluentes Químicos da Água , Brasil , Medição de Risco , Praguicidas/análise , Poluentes Químicos da Água/análise , Rios/química , Humanos , Monitoramento Ambiental/métodos , Cidades
13.
Am J Primatol ; 86(7): e23625, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38558023

RESUMO

Saimiri cassiquiarensis cassiquiarensis (Cebidae) is a primate subspecies with a wide distribution in the Amazonian region of Brazil, Colombia, and Venezuela. However, the boundaries of its geographic range remain poorly defined. This study presents new occurrence localities for this subspecies and updates its distribution using a compiled data set of 140 occurrence records based on literature, specimens vouchered in scientific collections, and new field data to produce model-based range maps. After cleaning our data set, we updated the subspecies' extent of occurrence, which was used in model calibration. We then modeled the subspecies' range using a maximum entropy algorithm (MaxEnt). The final model was adjusted using a fixed threshold, and we revised this polygon based on known geographic barriers and parapatric congeneric ranges. Our findings indicate that this subspecies is strongly associated with lowland areas, with consistently high daily temperatures. We propose modifications to all range boundaries and estimate that 3% of the area of occupancy (AOO, as defined by IUCN) has already been lost due to deforestation, resulting in a current range of 224,469 km2. We also found that 54% of their AOO is currently covered by protected areas (PAs). Based on these results, we consider that this subspecies is currently properly classified as Least Concern, because it occupies an extensive range, which is relatively well covered by PAs, and is currently experiencing low rates of deforestation.


Saimiri cassiquiarensis cassiquiarensis (Cebidae) é uma subespécie de primata com ampla distribuição na região amazônica do Brasil, Colômbia e Venezuela. No entanto, os limites de sua distribuição geográfica permanecem mal definidos. Este estudo apresenta novas localidades de ocorrência para essa subespécie e atualiza sua distribuição usando 140 registros de ocorrência compilados com base na literatura, espécimes depositados em coleções científicas e novos registros de campo para produzir mapas de distribuição baseados em modelos. Após a limpeza do nosso banco de dados, atualizamos a extensão de ocorrência da subespécie, que foi usada na calibração do modelo. Em seguida, modelamos a área de distribuição da subespécie usando um algoritmo de entropia máxima (MaxEnt). O modelo final foi ajustado usando um limiar fixo e revisamos esse polígono com base em barreiras geográficas conhecidas e na distribuição de congêneres parapátricas. Nosso modelo sugere que a espécie é fortemente associada a áreas planas, com temperaturas diárias consistentemente altas. Propomos modificações em todos os limites da área de distribuição e estimamos que 3% da área de ocupação (AOO, conforme definida pela IUCN) da subespécie já foi perdida devido ao desmatamento, resultando em uma área de distribuição atual de 224,469 km2. Também estimamos que 54% de sua AOO encontra­se atualmente coberta por áreas protegidas. Com base nesses resultados, consideramos que a subespécie está apropriadamente classificada como Pouco Preocupante, pois ocupa uma área extensa, que é relativamente bem coberta por áreas protegidas e atualmente apresenta baixas taxas de desmatamento.


Assuntos
Distribuição Animal , Saimiri , Animais , Saimiri/fisiologia , Venezuela , Brasil , Colômbia , Conservação dos Recursos Naturais , Ecossistema
14.
Proc Natl Acad Sci U S A ; 118(40)2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34580207

RESUMO

This paper addresses an important debate in Amazonian studies; namely, the scale, intensity, and nature of human modification of the forests in prehistory. Phytolith and charcoal analysis of terrestrial soils underneath mature tierra firme (nonflooded, nonriverine) forests in the remote Medio Putumayo-Algodón watersheds, northeastern Peru, provide a vegetation and fire history spanning at least the past 5,000 y. A tree inventory carried out in the region enables calibration of ancient phytolith records with standing vegetation and estimates of palm species densities on the landscape through time. Phytolith records show no evidence for forest clearing or agriculture with major annual seed and root crops. Frequencies of important economic palms such as Oenocarpus, Euterpe, Bactris, and Astrocaryum spp., some of which contain hyperdominant species in the modern flora, do not increase through prehistoric time. This indicates pre-Columbian occupations, if documented in the region with future research, did not significantly increase the abundance of those species through management or cultivation. Phytoliths from other arboreal and woody species similarly reflect a stable forest structure and diversity throughout the records. Charcoal 14C dates evidence local forest burning between ca. 2,800 and 1,400 y ago. Our data support previous research indicating that considerable areas of some Amazonian tierra firme forests were not significantly impacted by human activities during the prehistoric era. Rather, it appears that over the last 5,000 y, indigenous populations in this region coexisted with, and helped maintain, large expanses of relatively unmodified forest, as they continue to do today.


Assuntos
Incêndios , Florestas , Efeitos Antropogênicos , Peru
15.
Chem Biodivers ; 21(2): e202301568, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38252918

RESUMO

This study analyzed ten fish species (three farmed and seven wild-caught) to determine their centesimal composition (assessed by AOAC methods) and lipid profile (analyzed by GC-MS). Notably, "tambatinga" (farmed) and "piraputanga" (wild-caught) stood out with 28.66 % and 26.44 % protein content and 2.32 % and 3.71 % lipid content, respectively. Across all species, oleic acid was the predominant fatty acid, followed by linoleic acid. The sum of PUFAs ranged from 17.84 % in "matrinchã" to 7.85 % in "piraputanga". SFA varied from 49.93 % in "tambacu" to 39.90 % in "matrinchã", while MUFAs ranged from 44.34 % in "palmito" to 38.39 % in "tambaqui". "Matrinchã" had the highest average ω6 acid content (16.83 %), while "cachara" had the highest average for ω3 acids (5.73 %). "Piraputanga". "cachara", and "pincachara" exhibited the lowest ω6 levels. The analysis shows that fish have excellent nutritional values (proximate compositions) with few differences between species. "Pacu", "matrinchã", and "cachara" (wild-caught) demonstrated positive attributes, while "pincachara" (farmed) exhibited the highest nutritional quality in terms of fatty acid fraction. Based on quality indices (H/H), "pacu", "matrinchã" and "pincachara" are recommended choices for a healthy diet. This study adds valuable insights into the nutritional composition of fish species, which is essential for promoting regional development and local aquaculture.


Assuntos
Ácidos Graxos Insaturados , Ácidos Graxos , Animais , Ácidos Graxos/análise , Brasil , Ácidos Graxos Insaturados/análise , Peixes/metabolismo , Aquicultura
16.
J Environ Manage ; 359: 120864, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38714029

RESUMO

Deforestation rates in the Amazon have markedly increased in the last few years, affecting non-protected and protected areas (PAs). Brazil is a hotspot of Protected Area Downgrading, Downsizing, and Degazettement (PADDD) events, with most events associated with infrastructure projects. Despite the threats dams impose on PAs, there is a knowledge gap in assessing deforestation in PAs around large dams in the Amazon. This study investigates how deforestation affects Biodiversity Protection Areas (BioPAs) and Indigenous Lands around the Jirau and Santo Antônio (JSA) dams (Madeira River, Rondônia) and Belo Monte dam (Xingu River, Pará) in the Brazilian Amazon. We compared clear-cutting between PAs and control areas and the annual rates of forest change between pre-dam and post-dam periods. We discussed deforestation-related factors (e.g., PADDD events and the presence of management plans or councils). Our results show an increase in deforestation after the operation of the dams when environmental control from licensing agencies decreases and other political and economic factors are in practice. Indigenous Lands experienced a significant increase in deforestation around the Belo Monte dam, which is associated with the demarcation process and land conflicts. Surrounding the JSA dams, sustainable use BioPAs showed high deforestation rates, and 27 PADDD events were reported, four directly related to dams. In addition to dams, deforestation was associated with the crisis of Brazilian democracy and the weakening of environmental policies. In conclusion, the weak environmental control from environmental licensing agencies during dam operation and PADDD events have contributed to increased deforestation rates and additional stresses in the Amazon.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Brasil , Rios , Florestas
17.
Plant Foods Hum Nutr ; 79(1): 12-19, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38191770

RESUMO

Native species from the Amazonia are still unknown or underutilized and few information about their chemical and biological properties are available in the literature. Among the underutilized plant species in the Amazonia, Garcinia macrophylla can be seen as a promising source of bioactive compounds with relevant biological properties. The stem bark and leaves were the main investigated plant parts, mainly concerning the antioxidant, antibacterial, cytotoxicity and antidiabetic properties. However, the bioactive compounds and biological properties of the edible fruits were not yet reported. Systematic investigations covering the Amazonia biome, concerning plants and vegetables as strategic resources are of paramount importance for the sustainable development of the forest. Therefore, this review gathered the available information in the literature concerning general aspects, chemical profile and biological properties of G. macrophylla, for the first time, which highlighted that systematic and robust in vitro and in vivo research, are still needed to elucidate the phytochemical profiles and associated relevant biological properties.


Assuntos
Garcinia , Extratos Vegetais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Garcinia/química , Brasil , Antibacterianos/química , Folhas de Planta , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química
18.
Ecol Lett ; 26(2): 335-346, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36604979

RESUMO

Documenting patterns of spatiotemporal change in hyper-diverse communities remains a challenge for tropical ecology yet is increasingly urgent as some long-term studies have shown major declines in bird communities in undisturbed sites. In 1982, Terborgh et al. quantified the structure and organisation of the bird community in a 97-ha. plot in southeastern Peru. We revisited the same plot in 2018 using the same methodologies as the original study to evaluate community-wide changes. Contrary to longitudinal studies of other neotropical bird communities (Tiputini, Manaus, and Panama), we found little change in community structure and organisation, with increases in 5, decreases in 2 and no change in 7 foraging guilds. This apparent stability suggests that large forest reserves such as the Manu National Park, possibly due to regional topographical influences on precipitation, still provide the conditions for establishing refugia from at least some of the effects of global change on bird communities.


Assuntos
Biodiversidade , Parques Recreativos , Animais , Florestas , Ecologia , Aves
19.
Mol Biol Evol ; 39(1)2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34875092

RESUMO

South America is home to one of the most culturally diverse present-day native populations. However, the dispersion pattern, genetic substructure, and demographic complexity within South America are still poorly understood. Based on genome-wide data of 58 native populations, we provide a comprehensive scenario of South American indigenous groups considering the genomic, environmental, and linguistic data. Clear patterns of genetic structure were inferred among the South American natives, presenting at least four primary genetic clusters in the Amazonian and savanna regions and three clusters in the Andes and Pacific coast. We detected a cline of genetic variation along a west-east axis, contradicting a hard Andes-Amazon divide. This longitudinal genetic variation seemed to have been shaped by both serial population bottlenecks and isolation by distance. Results indicated that present-day South American substructures recapitulate ancient macroregional ancestries and western Amazonia groups show genetic evidence of cultural exchanges that led to language replacement in precontact times. Finally, demographic inferences pointed to a higher resilience of the western South American groups regarding population collapses caused by the European invasion and indicated precontact population reductions and demic expansions in South America.


Assuntos
Genética Populacional , Genômica , Variação Genética , Humanos , Indígenas Sul-Americanos/genética , Povos Indígenas , América do Sul , Indígena Americano ou Nativo do Alasca
20.
Ann Hum Genet ; 87(5): 210-221, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37161738

RESUMO

During the colonial period in South America, many autochthonous populations were affected by relocation by European missionary reductions and other factors that impacted and reconfigured their genetic makeup. Presently, the descendants of some "reduced" and other isolated groups are distributed in the Amazonian areas of Peru, Bolivia, and Brazil, and among them, speakers of Takanan and Panoan languages. Based on linguistics, these peoples should be closely related, but so far no DNA comparison studies have been conducted to corroborate a genetic relationship. To clarify these questions, we used a set of 15 short tandem repeats of the non-recombining part of the Y-chromosome (Y-STRs) and mitochondrial DNA (mtDNA) control region sequence data. Paternal line comparisons showed the Takanan-speaking peoples from Peru and Bolivia descended from recent common ancestors; one group was related to Arawakan, Jivaroan, and Cocama and the other to Panoan speakers, consistent with linguistics. Also, a genetic affinity for maternal lines was observed between some Takanan speakers and individuals who spoke different Amazonian languages. Our results supported a shared ancestry of Takanan, Panoan, Cocama, and Jivaroan-speaking communities who appeared to be related to each other and came likely from an early Arawak expansion in the western Amazonia of South America.


Assuntos
DNA Mitocondrial , Genética Populacional , Humanos , Bolívia , Peru , Haplótipos , Brasil , DNA Mitocondrial/genética , Cromossomos Humanos Y/genética , Variação Genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA