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1.
Proc Natl Acad Sci U S A ; 121(26): e2321068121, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38885390

RESUMO

An often-overlooked question of the biodiversity crisis is how natural hazards contribute to species extinction risk. To address this issue, we explored how four natural hazards, earthquakes, hurricanes, tsunamis, and volcanoes, overlapped with the distribution ranges of amphibians, birds, mammals, and reptiles that have either narrow distributions or populations with few mature individuals. To assess which species are at risk from these natural hazards, we combined the frequency and magnitude of each natural hazard to estimate their impact. We considered species at risk if they overlapped with regions where any of the four natural hazards historically occurred (n = 3,722). Those species with at least a quarter of their range subjected to a high relative impact were considered at high risk (n = 2,001) of extinction due to natural hazards. In total, 834 reptiles, 617 amphibians, 302 birds, and 248 mammals were at high risk and they were mainly distributed on islands and in the tropics. Hurricanes (n = 983) and earthquakes (n = 868) affected most species, while tsunamis (n = 272), and volcanoes (n = 171) affected considerably fewer. The region with the highest number of species at high risk was the Pacific Ring of Fire, especially due to volcanoes, earthquakes, and tsunamis, while hurricane-related high-risk species were concentrated in the Caribbean Sea, Gulf of Mexico, and northwestern Pacific Ocean. Our study provides important information regarding the species at risk due to natural hazards and can help guide conservation attention and efforts to safeguard their survival.


Assuntos
Biodiversidade , Extinção Biológica , Animais , Aves , Mamíferos , Répteis , Terremotos , Tempestades Ciclônicas , Tsunamis , Anfíbios , Erupções Vulcânicas , Desastres Naturais
2.
Front Plant Sci ; 12: 637508, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33927734

RESUMO

The Target of Rapamycin (TOR) kinase pathway integrates energy and nutrient availability into metabolism promoting growth in eukaryotes. The overall higher efficiency on nutrient use translated into faster growth rates in C4 grass plants led to the investigation of differential transcriptional and metabolic responses to short-term chemical TOR complex (TORC) suppression in the model Setaria viridis. In addition to previously described responses to TORC inhibition (i.e., general growth arrest, translational repression, and primary metabolism reprogramming) in Arabidopsis thaliana (C3), the magnitude of changes was smaller in S. viridis, particularly regarding nutrient use efficiency and C allocation and partitioning that promote biosynthetic growth. Besides photosynthetic differences, S. viridis and A. thaliana present several specificities that classify them into distinct lineages, which also contribute to the observed alterations mediated by TOR. Indeed, cell wall metabolism seems to be distinctly regulated according to each cell wall type, as synthesis of non-pectic polysaccharides were affected in S. viridis, whilst assembly and structure in A. thaliana. Our results indicate that the metabolic network needed to achieve faster growth seems to be less stringently controlled by TORC in S. viridis.

3.
Biol Invasions ; 23(3): 741-754, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679211

RESUMO

Invasive species can significantly affect native species when their niches are similar. Ecological and morphological similarities between the invasive Australian palm, Archontophoenix cunninghamiana, and the native palm from the Brazilian Atlantic Forest, Euterpe edulis, suggest that they have similar environmental requirements and functional roles (i.e., the function a species performs in an ecosystem). This similarity raises concerns about how the invasive palm could impact the native species in the present and future. We used spatial (species occurrences) and ecological information (frugivory events) to characterize the environmental niche and functional role of the two palms and assess their overlap. In addition, we predicted the potential area of occurrence of each palm within the Brazilian Atlantic Forest under current and future climate conditions.We estimated the environmental conditions used by the invasive plant based on its native distribution only, and based on all areas where the species is able to establish across the globe. We found that the environmental niches of the two palm species overlap up to 39%, which corresponds to 50% of the current geographic distribution of E. edulis in the Atlantic Forest. In the areas where the two species potentially co-occur, the impact of the invasive species on the native should be influenced by the invasive species interactions with frugivores. We found that the frugivory functional role of the two palms was similar (84% overlap) which suggest that A. cunninghamiana might disrupt the seed dispersal of the native palm. However, co-occurrence between the palms may decline with future climate change, as the potentially environmental suitable area for the invasive palm is predicted to decline by 10% to 55%. Evaluating the similarity in both the environmental niche, of the native and global extent, and the functional role of native and invasive plants provides a detailed understanding of the potential impact of invasive species on native species now and in the future.

4.
Adv Exp Med Biol ; 1346: 91-105, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35113397

RESUMO

Metabolomics is a valuable approach used to acquire comprehensive information about the set of metabolites in a cell or tissue, enabling a functional screen of the cellular activities in biological systems. Although metabolomics provides a more immediate and dynamic picture of phenotypes in comparison to the other omics, it is also the most complicated to measure because no single analytical technology can capture the extraordinary complexity of metabolite diversity in terms of structure and physical properties. Metabolomics has been extensively employed for a wide range of applications in plant science, which will be described in detail in this chapter. Among them, metabolomics is used for discriminating patterns of plant responses to genetic and environmental perturbations, as diagnostics and prediction tool to elucidate the function of genes for important and complex agronomic traits in crop species, and flux measurements are used to dissect the structure and regulatory properties of metabolic networks.


Assuntos
Metabolômica , Biologia de Sistemas , Genótipo , Fenótipo , Plantas/genética
5.
Ecology ; 99(2): 498, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29399824

RESUMO

Measures of traits are the basis of functional biological diversity. Numerous works consider mean species-level measures of traits while ignoring individual variance within species. However, there is a large amount of variation within species and it is increasingly apparent that it is important to consider trait variation not only between species, but also within species. Mammals are an interesting group for investigating trait-based approaches because they play diverse and important ecological functions (e.g., pollination, seed dispersal, predation, grazing) that are correlated with functional traits. Here we compile a data set comprising morphological and life history information of 279 mammal species from 39,850 individuals of 388 populations ranging from -5.83 to -29.75 decimal degrees of latitude and -34.82 to -56.73 decimal degrees of longitude in the Atlantic forest of South America. We present trait information from 16,840 individuals of 181 species of non-volant mammals (Rodentia, Didelphimorphia, Carnivora, Primates, Cingulata, Artiodactyla, Pilosa, Lagomorpha, Perissodactyla) and from 23,010 individuals of 98 species of volant mammals (Chiroptera). The traits reported include body mass, age, sex, reproductive stage, as well as the geographic coordinates of sampling for all taxa. Moreover, we gathered information on forearm length for bats and body length and tail length for rodents and marsupials. No copyright restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.

6.
Sci Rep ; 7(1): 7662, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28794422

RESUMO

The extinction of large frugivores has consequences for the recruitment of large-seeded plants with potential lasting effects on carbon storage in tropical rainforests. However, previous studies relating frugivore defaunation to changes in carbon storage ignore potential compensation by redundant frugivores and the effects of seed predators on plant recruitment. Based on empirical data of the recruitment success of a large-seeded hardwood tree species (Cryptocarya mandioccana, Lauraceae) across a defaunation gradient of seed dispersers and predators, we show that defaunation increases both seed dispersal limitation and seed predation. Depending on the level of seed predator loss, plant recruitment is reduced by 70.7-94.9% as a result of the loss of seed dispersers. The loss of large seed predators increases the net seed mortality by 7-30% due to the increased abundance of small granivorous rodents. The loss of large seed dispersers can be buffered by the compensatory effects of smaller frugivores in seed removal, but it is not sufficient to prevent a decrease in plant recruitment. We show that the conservation of both seed predators and dispersers is necessary for the recruitment of large-seeded plants. Since these plants contribute substantially to carbon stocks, defaunation can jeopardize the maintenance of tropical forest carbon storage.


Assuntos
Ciclo do Carbono , Ecossistema , Comportamento Predatório , Floresta Úmida , Dispersão de Sementes , Animais , Clima Tropical
7.
Ecology ; 98(8): 2226, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28500789

RESUMO

The contribution of small mammal ecology to the understanding of macroecological patterns of biodiversity, population dynamics, and community assembly has been hindered by the absence of large datasets of small mammal communities from tropical regions. Here we compile the largest dataset of inventories of small mammal communities for the Neotropical region. The dataset reviews small mammal communities from the Atlantic forest of South America, one of the regions with the highest diversity of small mammals and a global biodiversity hotspot, though currently covering less than 12% of its original area due to anthropogenic pressures. The dataset comprises 136 references from 300 locations covering seven vegetation types of tropical and subtropical Atlantic forests of South America, and presents data on species composition, richness, and relative abundance (captures/trap-nights). One paper was published more than 70 yr ago, but 80% of them were published after 2000. The dataset comprises 53,518 individuals of 124 species of small mammals, including 30 species of marsupials and 94 species of rodents. Species richness averaged 8.2 species (1-21) per site. Only two species occurred in more than 50% of the sites (the common opossum, Didelphis aurita and black-footed pigmy rice rat Oligoryzomys nigripes). Mean species abundance varied 430-fold, from 4.3 to 0.01 individuals/trap-night. The dataset also revealed a hyper-dominance of 22 species that comprised 78.29% of all individuals captured, with only seven species representing 44% of all captures. The information contained on this dataset can be applied in the study of macroecological patterns of biodiversity, communities, and populations, but also to evaluate the ecological consequences of fragmentation and defaunation, and predict disease outbreaks, trophic interactions and community dynamics in this biodiversity hotspot.


Assuntos
Biodiversidade , Florestas , Mamíferos/classificação , Animais , Marsupiais , Roedores , América do Sul
8.
Ecology ; 98(6): 1729, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28317110

RESUMO

The data set provided here includes 8,320 frugivory interactions (records of pairwise interactions between plant and frugivore species) reported for the Atlantic Forest. The data set includes interactions between 331 vertebrate species (232 birds, 90 mammals, 5 fishes, 1 amphibian, and 3 reptiles) and 788 plant species. We also present information on traits directly related to the frugivory process (endozoochory), such as the size of fruits and seeds and the body mass and gape size of frugivores. Data were extracted from 166 published and unpublished sources spanning from 1961 to 2016. While this is probably the most comprehensive data set available for a tropical ecosystem, it is arguably taxonomically and geographically biased. The plant families better represented are Melastomataceae, Myrtaceae, Moraceae, Urticaceae, and Solanaceae. Myrsine coriacea, Alchornea glandulosa, Cecropia pachystachya, and Trema micrantha are the plant species with the most animal dispersers (83, 76, 76, and 74 species, respectively). Among the animal taxa, the highest number of interactions is reported for birds (3,883) followed by mammals (1,315). The woolly spider monkey or muriqui, Brachyteles arachnoides, and Rufous-bellied Thrush, Turdus rufiventris, are the frugivores with the most diverse fruit diets (137 and 121 plants species, respectively). The most important general patterns that we note are that larger seeded plant species (>12 mm) are mainly eaten by terrestrial mammals (rodents, ungulates, primates, and carnivores) and that birds are the main consumers of fruits with a high concentration of lipids. Our data set is geographically biased, with most interactions recorded for the southeast Atlantic Forest.


Assuntos
Comportamento Alimentar , Florestas , Fungos , Animais , Aves , Frutas , Herbivoria , Plantas
9.
Sci Adv ; 1(11): e1501105, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26824067

RESUMO

Carbon storage is widely acknowledged as one of the most valuable forest ecosystem services. Deforestation, logging, fragmentation, fire, and climate change have significant effects on tropical carbon stocks; however, an elusive and yet undetected decrease in carbon storage may be due to defaunation of large seed dispersers. Many large tropical trees with sizeable contributions to carbon stock rely on large vertebrates for seed dispersal and regeneration, however many of these frugivores are threatened by hunting, illegal trade, and habitat loss. We used a large data set on tree species composition and abundance, seed, fruit, and carbon-related traits, and plant-animal interactions to estimate the loss of carbon storage capacity of tropical forests in defaunated scenarios. By simulating the local extinction of trees that depend on large frugivores in 31 Atlantic Forest communities, we found that defaunation has the potential to significantly erode carbon storage even when only a small proportion of large-seeded trees are extirpated. Although intergovernmental policies to reduce carbon emissions and reforestation programs have been mostly focused on deforestation, our results demonstrate that defaunation, and the loss of key ecological interactions, also poses a serious risk for the maintenance of tropical forest carbon storage.

10.
Int J Mol Sci ; 14(7): 13796-807, 2013 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-23823801

RESUMO

Changes in flower morphology may influence the frequency and specificity of animal visitors. In Petunia (Solanaceae), adaptation to different pollinators is one of the factors leading to species diversification within the genus. This study provides evidence that differential expression patterns of MAWEWEST (MAW) homologs in different Petunia species may be associated with adaptive changes in floral morphology. The Petunia × hybrida MAW gene belongs to the WOX (WUSCHEL-related homeobox) transcription factor family and has been identified as a controller of petal fusion during corolla formation. We analyzed the expression patterns of P. inflata and P. axillaris MAW orthologs (PiMAW and PaMAW, respectively) by reverse transcriptase polymerase chain reaction (RT-PCR), reverse transcription-quantitative PCR (qRT-PCR) and in situ hybridization in different tissues and different developmental stages of flowers in both species. The spatial expression patterns of PiMAW and PaMAW were similar in P. inflata and P. axillaris. Nevertheless, PaMAW expression level in P. axillaris was higher during the late bud development stage as compared to PiMAW in P. inflata. This work represents an expansion of petunia developmental research to wild accessions.


Assuntos
Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Homeodomínio/biossíntese , Petunia/metabolismo , Proteínas de Plantas/biossíntese , Flores/genética , Proteínas de Homeodomínio/genética , Petunia/genética , Proteínas de Plantas/genética
11.
Dermatol. argent ; 17(3): 214-220, mayo-jun. 2011. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-724170

RESUMO

La dermatosis congénita vesicular y erosiva con cicatrices reticuladas es un raro desorden cutáneo de etiología desconocida con lesiones evidentes al nacimiento. Presentamos una niña con esta condición, la cual representa el primer caso diagnosticado en la Argentina, junto a una revisión dela literatura.


Congenital erosive and vesicular dermatosis healing with reticulated, supple scarring is a rare cutaneouscondition of unknown etiology. It presents with patchy or generalized erosion and vesiclesrecognizable at birth, that heal with reticulated scarring. We report a female child with thiscondition, the first recognized in Argentina, together with a review of the literature.


Assuntos
Humanos , Criança , Feminino , Dermatopatias Vesiculobolhosas/complicações , Dermatopatias Vesiculobolhosas/congênito , Dermatopatias Vesiculobolhosas/patologia , Cicatriz/etiologia , Pele/patologia
12.
Dermatol. pediatr. latinoam. (Impr.) ; 9(1): 20-23, ene.-abr. 2011. ilus
Artigo em Espanhol | LILACS | ID: lil-680275

RESUMO

La dermatosis pustular erosiva del cuero cabelludo es una erupción pustular idiopática que se ha asociado al trauma físico, quirúrgico o a tratamientos médicos. Se presenta una niña que desarrolla este cuadro como consecuencia del trauma quirúrgico provocado por el drenaje de múltiples abscesos en el cuero cabelludo


Erosive pustular dermatosis of the scalp is characterized by idiopathic pustular eruption often triggered by physical, medical or surgical trauma. We present a girl of 6 years of age that developed this disease as a consequence of surgical trauma after multiple scalp abscesses drainage


Assuntos
Humanos , Feminino , Criança , Diagnóstico Diferencial , Exantema , Dermatoses do Couro Cabeludo
13.
Dermatol. pediatr. latinoam. (Impr.) ; 8(1): 35-38, ene.-abr. 2010. graf
Artigo em Espanhol | LILACS | ID: lil-598221

RESUMO

La urticaria-vasculitis es una forma de vasculitis que se presenta en forma de habones eritematosos clínicamente semejantes a la urticaria hemorrágica de tipo alérgica, pero que histológicamente muestra cambios de vasculitis leucocitoclástica. Puede acompañarse de normocomplementemia o hipocomplementemia. En ambas situaciones puede estar asociada a síntomas sistémicos (como por ejemplo, angioedema, artralgias, dolor abdominal, fiebre, enfermedad pulmonar o renal, epiescleritis y uveitis), aunque en los casos en que se acompaña de hipocomplementemia ha sido vinculada con mayor frecuencia a enfermedades del tejido conectivo. El estudio histopatológico permite diferenciar la urticaria hemorrágica alérgica de la urticaria-vasculitis. Presentamos una niña de 5 años con urticaria-vasculitis y normocomplementemia, con lesiones cutáneas típicas asociadas a artralgias y dolor abdominal.


Urticarial vasculitis is an eruption of erythematous wheals that clinically resemble urticaria but histollogicaly shows leukocytoclastic vasculitis. Urticarial vasculitis may be divided into normocomplementemic and hypocomplementemic variants. Both subsets can be associated with systemic symptoms (for example, angioedema, arthralgias, abdominal or chest pain, fever, pulmonary or renal disease, epiescleritis and uveitis), more often the second variant which has been linked to connective-tissue disease. Histopathological evaluation allows to differentiate between hemorrhagic allergic urticaria and urticarial vasculitis. We report the case of a 5-year-old girl presenting with normocomplementemic uticarial vasculitis, with typical cutaneous lesions associated to arthralgias and abdominal pain.


Assuntos
Humanos , Feminino , Pré-Escolar , Criança , Vasculite por IgA , Vasculite Leucocitoclástica Cutânea , Dor Abdominal , Artralgia , Urticária
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