Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros








Intervalo de ano de publicação
1.
Sci Data ; 10(1): 757, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919263

RESUMO

Incomplete information on parasites, their associated hosts, and their precise geographical location hampers the ability to predict disease emergence in Brazil, a continental-sized country characterised by significant regional disparities. Here, we demonstrate how the NCBI Nucleotide and GBIF databases can be used as complementary databases to study spatially georeferenced parasite-host associations. We also provide a comprehensive dataset of parasites associated with mammal species that occur in Brazil, the Brazilian Mammal Parasite Occurrence Data (BMPO). This dataset integrates wild mammal species' morphological and life-history traits, zoonotic parasite status, and zoonotic microparasite transmission modes. Through meta-networks, comprising interconnected host species linked by shared zoonotic microparasites, we elucidate patterns of zoonotic microparasite dissemination. This approach contributes to wild animal and zoonoses surveillance, identifying and targeting host species accountable for disproportionate levels of parasite sharing within distinct biomes. Moreover, our novel dataset contributes to the refinement of models concerning disease emergence and parasite distribution among host species.


Assuntos
Interações Hospedeiro-Parasita , Parasitos , Animais , Animais Selvagens , Brasil , Mamíferos/parasitologia , Análise Espacial
2.
J Anim Ecol ; 92(2): 324-337, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36059124

RESUMO

Studying species interactions in nature often requires elaborated logistics and intense fieldwork. The difficulties in such task might hinder our ability to answer questions on how biotic interactions change with the environment. Fortunately, a workaround to this problem lies within scientific collections. For some animals, the inspection of preserved specimens can reveal the scars of past antagonistic encounters, such as predation attempts. A common defensive behaviour that leaves scars on animals is autotomy, the loss of a body appendage to escape predation. By knowing the collection site of preserved specimens, it is possible to assess the influence of organismal biology and the surrounding environment in the occurrence of autotomy. We gathered data on tail loss for 8189 preserved specimens of 33 snake and 11 amphisbaenian species to investigate biological and environmental correlates of autotomy in reptiles. We applied generalized linear mixed effect models to evaluate whether body size, sex, life-stage, habitat use, activity pattern, biome, tropicality, temperature and precipitation affect the probability of tail loss in limbless reptiles. We observed autotomy in 23.6% of examined specimens, with 18.7% of amphisbaenian and 33.4% of snake specimens showing tail loss. The probability of tail loss did not differ between snakes and amphisbaenians, but it was higher among large-sized specimens, particularly in adults and females. Chance of tail loss was higher for diurnal and arboreal species, and among specimens collected in warmer regions, but it was unaffected by biome, precipitation, and tropicality. Autotomy in limbless reptiles was affected by size-dependent factors that interplay with ontogeny and sexual dimorphism, although size-independent effects of life-stage and sex also shaped behavioural responses to predators. The increase in probability of tail loss with verticality and diurnality suggests a risk-balance mechanism between species habitat use and activity pattern. Although autotomy is more likely in warmer regions, it seems unrelated to seasonal differences in snakes and amphisbaenians activity. Our findings reveal several processes related to predator-prey interactions involving limbless reptiles, demonstrating the importance of scientific collections to unveil ecological mechanisms at different spatio-temporal scales.


Assuntos
Lagartos , Feminino , Animais , Lagartos/fisiologia , Cauda/fisiologia , Comportamento Predatório , Cicatriz , Ecossistema
3.
Sci Adv ; 8(26): eabo5774, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35767624

RESUMO

In developing countries, outbreaks of zoonotic diseases (ZDs) result from intertwined ecological, socioeconomic, and demographic processes that shape conditions for (i) increased contact between vulnerable human population and wildlife in areas undergoing environmental degradation and (ii) the rapid geographic spread of infections across socially vulnerable regions. In Brazil, recent increases in environmental and social vulnerabilities, amplified by economic and political crises, are potential triggers for outbreaks. We discuss Brazilian features that favor outbreaks and show a novel quantitative method for zoonotic risk assessment. Using data on nine ZDs from 2001 to 2019, we found that the most significant causal variables were vegetation cover and city remoteness. Furthermore, 8 of 27 states presented low-level risk of ZD outbreaks. Given the ZD-bushmeat connection, we identified central hunted mammals that should be surveilled to prevent spillover events. The current challenge is to coordinate intersectoral collaboration for effective One Health management in megadiverse countries with high social vulnerability and growing environmental degradation like Brazil.

4.
Parasitol Res ; 120(3): 797-806, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33068151

RESUMO

The number of reports of tick parasitism in amphibians and reptiles has increased over the past few years, including new host and location records for Amblyomma rotundatum and Amblyomma dissimile. However, knowledge of the geographical distribution remains incomplete, and in many regions of Brazil, the presence of these vectors has not been investigated. Several candidate models were built using a correlative maximum entropy approach, and best-fitting models were selected based on statistical significance, predictive ability, and complexity based on current climatic trends and future projected climate changes. Final models showed a good ability to discriminate A. rotundatum and A. dissimile current and future potential distributions. The entire country had higher predicted suitability for A. rotundatum while A. dissimile was mainly restricted to the Amazon and Pantanal biomes. A. rotundatum is a species with enormous potential for dissemination in the next decades, potentially through the legal and illegal transport of reptiles and amphibians. The proposed model is useful for targeting surveillance efforts increasing the efficiency and accuracy of future ecological research and tick management efforts.


Assuntos
Amblyomma/fisiologia , Infestações por Carrapato/parasitologia , Amblyomma/classificação , Anfíbios/parasitologia , Distribuição Animal , Animais , Brasil , Ecossistema , Répteis/parasitologia
6.
Parasitol Res, v. 120, p. 797–806, oct. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3278

RESUMO

The number of reports of tick parasitism in amphibians and reptiles has increased over the past few years, including new host and location records for Amblyomma rotundatum and Amblyomma dissimile. However, knowledge of the geographical distribution remains incomplete, and in many regions of Brazil, the presence of these vectors has not been investigated. Several candidate models were built using a correlative maximum entropy approach, and best-fitting models were selected based on statistical significance, predictive ability, and complexity based on current climatic trends and future projected climate changes. Final models showed a good ability to discriminate A. rotundatum and A. dissimile current and future potential distributions. The entire country had higher predicted suitability for A. rotundatum while A. dissimile was mainly restricted to the Amazon and Pantanal biomes. A. rotundatum is a species with enormous potential for dissemination in the next decades, potentially through the legal and illegal transport of reptiles and amphibians. The proposed model is useful for targeting surveillance efforts increasing the efficiency and accuracy of future ecological research and tick management efforts.

7.
PLoS One ; 14(3): e0213368, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30893352

RESUMO

Changing forest cover is a key driver of local climate change worldwide, as it affects both albedo and evapotranspiration (ET). Deforestation and forestation are predicted to have opposing influences on surface albedo and ET rates, and thus impact local surface temperatures differently. Relationships between forest change, albedo, ET, and local temperatures may further vary regionally, as the strengths of warming by albedo effects and cooling by ET effects vary with latitude. Despite these important relationships, the magnitude of forest cover effects on local surface temperature across the globe remains unclear. Using recently-released global forest change data, we first show that forestation and deforestation have pervasive and opposite effects on LST, ET and albedo worldwide. Deforestation from 2000 to 2010 caused consistent warming of 0.38 ± 0.02 (mean ± SE) and 0.16 ± 0.01°C in tropical and temperate regions respectively, while forestation caused cooling in those regions of -0.18 ± 0.02 and -0.19 ± 0.02°C. Tropical forests were particularly sensitive to the climate effects of forest change, with forest cover losses of ~50% associated with increased LST of 1.08 ± 0.25°C, whereas similar forest cover gains decreased LST by -1.11 ± 0.26°C. Secondly, based on a new structural equation model, we show that these changes on LST were largely mediated by changes in albedo and ET. Finally, based on this model, we show that predicted forest changes in Brazil associated with a business-as-usual land use scenario through 2050 may increase LST up to 1.45°C. Our results contribute to a better understanding of the mechanistic inter-relationships between forest change and changes in albedo, ET and LST, and provide additional evidence that forestation has the potential to reverse deforestation impacts on local climate, especially in tropical and temperate regions.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Florestas , Brasil , Modelos Teóricos , Temperatura , Clima Tropical
8.
An Acad Bras Cienc ; 91(1): e20170403, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30569964

RESUMO

Data on the structure of lizard communities in the different biomes and ecosystems of Brazil are still limited. In this study, we related the species richness, abundance and the spatial occurrence of lizards to the structure of the vegetation found on the coast of the state of Espírito Santo, southeastern Brazil, to determine whether habitat influences the structure of lizard communities. We conducted fieldwork in 2012, 2013 and 2014, collecting data in standardized samples. We analyze whether variables of vegetation structure influenced species richness and abundance, using Generalized Linear Models (GLMs). We recorded 12 lizard species from eight families. In general, species richness and abundance were similar among sites. Locally, we recorded the highest species richness in shrubby vegetation, open Clusia vegetation, and the restinga forest zone. Bromeliads explained the occurrence of teiids, although there was no systematic relationship between species richness and vegetation structure. Our results provide important insights into the characteristics of the lizard communities found on sandy coastal plains and contribute to the conservation of these species in these ecosystems.


Assuntos
Ecossistema , Lagartos , Distribuição Animal , Animais , Biodiversidade , Brasil , Lagartos/classificação , Parques Recreativos , Plantas , Densidade Demográfica , Dinâmica Populacional
9.
An Acad Bras Cienc ; 88 Suppl 1: 677-87, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27142553

RESUMO

Communities are structured by interactions of historical and ecological factors, which influence the use of different resources in time and space. We acquired data on time of activity, microhabitat use and diet of a lizard assemblage from a sand dune habitat in a coastal area, southeastern Brazil (Restinga de Jurubatiba). We analyzed the data of niche overlap among species in these three axes (temporal, spatial and trophic) using null models. We found a significant overlap within the trophic niche, whereas the overlap for the other axes did not differ from the expected. Based on this result, we discuss the factors acting on the structure of the local lizard community.


Assuntos
Ecossistema , Lagartos , Simpatria , Animais , Brasil , Dieta , Lagartos/classificação , Dinâmica Populacional , Floresta Úmida
10.
An Acad Bras Cienc ; 86(2): 695-706, 2014 06.
Artigo em Inglês | MEDLINE | ID: mdl-24770455

RESUMO

Viperid snakes are widely distributed in the South America and the greater distribution range of the family is found at the Crotalinae subfamily. Despite the abundance of this snakes along their geographic distribution, some ecological aspects remain unknown, principally at subtropical areas. In the present study, we evaluated the activity (daily and seasonal) and the use of the habitat by Bothrops diporus, B. jararaca and B. jararacussu, in an Atlantic Forest area at southern Brazil. We observed higher incidence of viperid snakes during the months with higher temperatures, while no snakes were found during the months with lower temperatures. The data suggest the minimum temperature as environmental variable with the greatest influence on the seasonal activity of this species. Considering the daily activity, we observed a tendency of snakes to avoid the warmest hours. Bothrops jararacussu tend to avoid open areas, being registered only inside and at the edges of the forest. We compared our results with previous studies realized at tropical areas and we suggest the observed seasonal activity as an evolutive response, despite the influence of the different environmental variables, according to the occurence region.

11.
Syst Parasitol ; 85(2): 195-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23673697

RESUMO

A new coccidian species of the genus Caryospora Léger, 1904 (Protozoa, Apicomplexa, Eimeriidae) is reported from the colubrid snake host Philodryas olfersii Lichtenstein at a coastal area in the State of Rio de Janeiro, south-eastern Brazil. Oöcysts of Caryospora olfersii n. sp. are spherical to sub-spherical, 33.1 × 31.2 µm, with smooth, colourless, three-layered wall, c.1.4; middle layer lightly striated. Micropyle, oöcyst residuum and polar granule are all absent. Sporocysts are ovoid, 22.9 × 17.4 µm on average, with one extremity in the shape of a short neck. Stieda body present, 3.2 × 1.3 µm, sub-Stieda body present, homogeneous, larger than Stieda body, 4.5 × 1.7 µm. Sporozoites are inserted in a bulky sporocyst residuum.


Assuntos
Eimeriidae/classificação , Eimeriidae/isolamento & purificação , Serpentes/parasitologia , Animais , Brasil , Ecossistema , Eimeriidae/citologia , Microscopia , Esporos de Protozoários/citologia
12.
An Acad Bras Cienc ; 83(4): 1345-58, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22146962

RESUMO

The increasing human occupation of natural environments is one of the greatest threats to biodiversity. To mitigate the negative anthropogenic effects, it is necessary to understand the characteristics of natural populations and the natural history of species. A study was conducted with an assemblage of lizards from a disturbed area of the Pampa biome, from February 2001 to January 2004. The assemblage showed a unimodal seasonal pattern, with the recruitment period occurring during the warmer months. The captures were seasonal for two of the three monitored years, and concentrated within warmer months. The minimum temperature explained the number of catches for the assemblage as a whole. However, when the species were analyzed individually, the temperature only explained the seasonal occurrence of Teius oculatus. The abundance of species was significantly different in the third year of study for Cercosaura schreibersii and Ophiodes striatus. This latter species was no longer registered in the study area from May 2003 until the end of the study. Therefore, O. striatus may be more sensitive to environmental changes, considering the events of change in vegetation during the study. With frequent and increasing environmental disturbances, it is necessary to take conservation measures and encourage the increase of knowledge on Pampean lizards.


Assuntos
Biodiversidade , Monitoramento Ambiental/métodos , Lagartos/classificação , Animais , Brasil , Densidade Demográfica , Dinâmica Populacional , Estações do Ano
13.
An. acad. bras. ciênc ; 83(4): 1345-1358, Dec. 2011. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-607430

RESUMO

The increasing human occupation of natural environments is one of the greatest threats to biodiversity. To mitigate the negative anthropogenic effects, it is necessary to understand the characteristics of natural populations and the natural history of species. A study was conducted with an assemblage of lizards from a disturbed area of the Pampa biome, from February 2001 to January 2004. The assemblage showed a unimodal seasonal pattern, with the recruitment period occurring during the warmer months. The captures were seasonal for two of the three monitored years, and concentrated within warmer months. The minimum temperature explained the number of catches for the assemblage as a whole. However, when the species were analyzed individually, the temperature only explained the seasonal occurrence of Teius oculatus. The abundance of species was significantly different in the third year of study for Cercosaura schreibersii and Ophiodes striatus. This latter species was no longer registered in the study area from May 2003 until the end of the study. Therefore, O. striatus may be more sensitive to environmental changes, considering the events of change in vegetation during the study. With frequent and increasing environmental disturbances, it is necessary to take conservation measures and encourage the increase of knowledge on Pampean lizards.


O crescimento da ocupação humana sobre ambientes naturais é uma das maiores ameaças à biodiversidade. Para amenizar os efeitos negativos antropogênicos, é necessário entender as características das populações naturais, e a história natural das espécies. Um estudo foi conduzido com uma assembeia de lagartos de uma área perturbada do Pampa, de fevereiro de 2002 a janeiro de 2004. A assembleia apresentou padrão sazonal unimodal, com recrutamento ocorrendo durante os meses mais quentes. As capturas foram sazonais durante dois dos três anos monitorados, e concentradas nos meses mais quentes. A temperatura mínima explica o número de capturas para a assembleia como um todo. Entretanto, quando as espécies foram analisadas individualmente, a variável explica apenas a ocorrência sazonal de Teius oculatus. A abundância das espécies foi significativamente distinta no terceiro ano de estudo para Cercosaura schreibersii e Ophiodes striatus. Essa última espécie não teve mais registros na área de maio de 2003 até o final do estudo. Assim, O. striatus pode ser mais sensível às udanças abientais, considerando os eventos de udança na vegetação ocorridas durante o estudo. Com as frequentes e crescentes perturbações ambientais que o bioma vem sofrendo, são necessárias ações de conservação, e dar suporte para o aumento do conhecimento dos lagartos pampeanos.


Assuntos
Animais , Biodiversidade , Monitoramento Ambiental/métodos , Lagartos/classificação , Brasil , Densidade Demográfica , Dinâmica Populacional , Estações do Ano
14.
An Acad Bras Cienc ; 82(4): 983-96, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21152772

RESUMO

The Quaternary fossil record of Águas de Araxá (Q AA) is represented mainly by an accumulation of skeletal elements of several sizes, which are assigned to a population of Stegomastodon waringi. We analyzed 97 molars according to the ear stages of Simpson and Paula-Couto (1957), and developed a morphometric ear index. The population structure (proportion of immature, subadult, adult, mature adult and senile adult individuals) was identified, and these five age classes were compared to those of extant elephant populations and defined with social implications. The analysis made possible to establish that the population is largely composed of adults: 14.89% are immature individuals, 23.04% subadults, 27.65% adults, 17.21% mature adults and another 17.21% senile adults. Based on population structure, we do not discard the possibility that the fossil population was stable or in recovery, and/or was experiencing a high-predation period on younger individuals. The number of individuals composing the past population studied here could suggest that the occupied environment was open due to comparisons to populations of extant elephants. We consider this population as an aggregation of family units, which suggests a time of low environmental humidity. Based on literature and our findings, their extinction appears to be regional and probably related to a catastrophic event.


Assuntos
Elefantes/anatomia & histologia , Fósseis , Mastodontes/anatomia & histologia , Dente/anatomia & histologia , Animais , Brasil
15.
An. acad. bras. ciênc ; 82(4): 983-996, Dec. 2010. ilus, graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-567808

RESUMO

The Quaternary fossil record of Águas de Araxá (Q AA) is represented mainly by an accumulation of skeletal elements of several sizes, which are assigned to a population of Stegomastodon waringi. We analyzed 97 molars according to the ear stages of Sipson and Paula-Couto (1957), and developed a orphoetric ear index. The population structure (proportion of immature, subadult, adult, mature adult and senile adult individuals) was identified, and these five age classes were compared to those of extant elephant populations and defined with social implications. The analysis made possible to establish that the population is largely composed of adults: 14.89 percent are immature individuals, 23.04 percent subadults, 27.65 percent adults, 17.21 percent mature adults and another 17.21 percent senile adults. Based on population structure, we do not discard the possibility that the fossil population was stable or in recovery, and/or was experiencing a high-predation period on younger individuals. The number of individuals composing the past population studied here could suggest that the occupied environment was open due to comparisons to populations of extant elephants. We consider this population as an aggregation of family units, which suggests a time of low environmental humidity. Based on literature and our findings, their extinction appears to be regional and probably related to a catastrophic event.


O registro fossilífero do Quaternário de Águas de Araxá (QAA) é representado principalmente pelo acúmulo de restos dentários e de esqueleto de diversos tamanhos, atribuídos a uma população pretérita do mastodonte Stegomastodon waringi. Foram analisados 97 molares de acordo com os estágios de desgaste propostos por Simpson e Paula-Couto 1957, e desenvolveu-se um índice morfométrico de desgaste. A estrutura populacional (proporção entre indivíduos imaturos, subadultos, adultos, adultos maduros e adultos senis) foi identificada e comparada com populações de elefantes atuais. Foi possível estabelecer que esta população era amplamente composta por adultos: 14,89 por cento eram indivíduos imaturos; 23,04 por cento eram subadultos; 27,65 por cento eram adultos; 17,21 por cento eram adultos maduros e outros 17,21 por cento eram adultos senis. Baseados na estrutura populacional observada, não se descartou a possibilidade desta população estar estável ou em recuperação e/ou de ter passado por um período de predação dos indivíduos mais jovens. O número de indivíduos encontrados nesta população sugere que esta ocupava um ambiente aberto, de acordo com comparações com populações de elefantes atuais. Considerou-se a assembléia de mastodontes do Quaternário de Águas de Araxá como uma agregação de unidades familiares, o que sugere um momento de baixa umidade ambiental. Baseados em literatura e nos resultados encontrados, a sua extinção parece ser regional e possivelmente relacionada a um evento catastrófico.


Assuntos
Animais , Elefantes/anatomia & histologia , Fósseis , Mastodontes/anatomia & histologia , Dente/anatomia & histologia , Brasil
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA