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1.
Sci Total Environ ; 734: 139473, 2020 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-32464394

RESUMEN

Understanding spatiotemporal patterns of species distributions and their determinants is paramount in ecology. Here, we explore the relationship between the diversity of surviving mammals and two of the main alimentary resources (araucaria seeds and feijoa fruits) across the Araucaria Forest (FOM) in South America. First, we investigated the influence of landscape and environment on the species distribution and pulse of forest productivity. Then, we evaluated how these spatiotemporal pulses in resource availability influence the mammalian diversity. We analyzed the data via diversity descriptors, Morisita index and multiple regressions. Our findings highlighted that climate, tree density, and other environmental variables explained the pulses of productivity. Mammalian diversity of first-order consumers mammals-all those immediately feeding on seeds and fruits-was partially related to resource pulses. Our results revealed that the pulses of forest resources can influence mammal diversity over the years, including delayed responses and asynchronous oscillations. The integrity of vegetal elements of the FOM is key to maintain several mammal-mediated ecological processes. Maintaining the viability of tree populations, encouraging the sustainable use of non-timber resources, and promoting the conservation of the mammalian fauna, which is undergoing an unprecedented diversity crisis worldwide, can help to preserve the remaining ecological processes.


Asunto(s)
Biodiversidad , Mamíferos , Animales , Brasil , Bosques , Árboles
2.
PLoS One ; 14(12): e0226136, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31851714

RESUMEN

Melanism in the cat family has been associated with functions including camouflage, thermoregulation and parasite resistance. Here we investigate a new hypothesis proposing that the evolution of melanism in cats has additionally been influenced by communication functions of body markings. To evaluate this hypothesis, we assembled a species-level data set of morphological (body marks: white marks on the backs of ears) and ecological (circadian activity: arrhythmic/nocturnal, and environmental preference: open/closed) characteristics that could be associated with communication via body markings, and combined these data with a dated molecular phylogeny. Next, we tested the association between melanism and communication, first by relating species' body marks with their ecological conditions, using a Bayesian implementation of the threshold model. Second, to explore the evolution of characteristics potentially influencing melanism in cat species, we modeled their evolution relative to melanism using models of coordinated vs. independent character changes. Our results suggest that white marks are associated with intraspecific communication between individuals that have non-melanistic phenotypes, as well as towards melanistic individuals (without white marks). The absence of white marks in a melanistic individual tends to be a limiting condition for intraspecific visual communication at night, resulting in an evolutionary dilemma for these species, i.e. to be almost invisible at night, but not to communicate visually. The comparative analysis of several evolutionary models indicated more support for the evolution of melanism being coordinated with the evolution of arrhythmic activity and white marks on the backs of ears.


Asunto(s)
Evolución Biológica , Felidae , Color del Cabello , Melaninas , Comunicación Animal , Animales , Gatos , Modelos Biológicos
3.
Ecology ; 100(10): e02785, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31180132

RESUMEN

Biodiversity inventories contain important information about species richness, community structure, and composition, and are the first step in developing any conservation and mitigation strategies. The Atlantic Forest of South America is home to around 334 species of small-, medium-, and large-sized mammals, and is currently restricted to less than 12% of its original cover. Here, we present the ATLANTIC MAMMALS, an open data set on information on medium- and large-sized mammal assemblages in the Atlantic Forest of Brazil, Paraguay, and Argentina. A total of 129 studies were compiled, including published and in press peer-reviewed papers, book chapters, theses and unpublished data. We mapped 244 assemblages, eight orders, 63 genera, and 94 species (24 of which are classified as threatened by the IUCN Red List) distributed in 128 protected and 116 unprotected areas. Species richness of the mammalian assemblages varied from 1 to 39 species (mean 15). The most recorded species in the entire biome was Dasypus novemcinctus, followed by Cerdocyon thous and Procyon cancrivorous. These data can be useful in support of macroecological studies and conservation planning strategies. 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.

4.
Ecology ; 100(1): e02525, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30317556

RESUMEN

Primates play an important role in ecosystem functioning and offer critical insights into human evolution, biology, behavior, and emerging infectious diseases. There are 26 primate species in the Atlantic Forests of South America, 19 of them endemic. We compiled a dataset of 5,472 georeferenced locations of 26 native and 1 introduced primate species, as hybrids in the genera Callithrix and Alouatta. The dataset includes 700 primate communities, 8,121 single species occurrences and 714 estimates of primate population sizes, covering most natural forest types of the tropical and subtropical Atlantic Forest of Brazil, Paraguay and Argentina and some other biomes. On average, primate communities of the Atlantic Forest harbor 2 ± 1 species (range = 1-6). However, about 40% of primate communities contain only one species. Alouatta guariba (N = 2,188 records) and Sapajus nigritus (N = 1,127) were the species with the most records. Callicebus barbarabrownae (N = 35), Leontopithecus caissara (N = 38), and Sapajus libidinosus (N = 41) were the species with the least records. Recorded primate densities varied from 0.004 individuals/km2 (Alouatta guariba at Fragmento do Bugre, Paraná, Brazil) to 400 individuals/km2 (Alouatta caraya in Santiago, Rio Grande do Sul, Brazil). Our dataset reflects disparity between the numerous primate census conducted in the Atlantic Forest, in contrast to the scarcity of estimates of population sizes and densities. With these data, researchers can develop different macroecological and regional level studies, focusing on communities, populations, species co-occurrence and distribution patterns. Moreover, the data can also be used to assess the consequences of fragmentation, defaunation, and disease outbreaks on different ecological processes, such as trophic cascades, species invasion or extinction, and community dynamics. There are no copyright restrictions. 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.

5.
PLoS One ; 13(9): e0204515, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30252909

RESUMEN

Mammals represent the largest-bodied elements of the world's surviving megafauna and provide several key ecosystems services, yet their populations are often under steep decline throughout the tropics. Anthropogenic defaunation is one the most important contemporary threats to modern mammal faunas. Although the Atlantic Forest biome of South America shows several clear signs of defaunation, the extent to which this biome has lost its mammal fauna remains poorly understood. Here, we collate and analyze a comprehensive body of secondary data to quantitatively assess the spatial patterns of defaunation of all medium- to large-bodied Atlantic Forest mammals which were then classed by morpho-ecological traits. We used a Defaunation Index, which was scaled-up to the entire biome using kriging interpolation, to examine the integrity of site-specific mammal faunas. We further use environmental and socioeconomic predictors to explain the drivers of defaunation. Our results show high levels of defaunation (>0.5) for most of the Atlantic Forest. Apex predators, other carnivores, large-bodied mammals and large herbivores were among the most defaunated functional groups. Remaining native vegetation cover, forest fragment size, and the largest neighboring forest remnant were the main negative predictors of defaunation. We conclude that medium- to large-bodied Atlantic Forest mammals are under high levels of threat due to historical population losses that continue today. A conservation action plan thus becomes imperative to prevent this biome from becoming an even "emptier forest", severely compromising patterns of diversity, ecological processes and ecosystem functioning.


Asunto(s)
Conservación de los Recursos Naturales , Bosques , Mamíferos , Animales , Argentina , Océano Atlántico , Biodiversidad , Brasil , Conservación de los Recursos Naturales/economía , Ecosistema , Humanos , Mamíferos/anatomía & histología , Dinámica Poblacional , Factores Socioeconómicos
6.
PLoS One ; 13(4): e0195199, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29617455

RESUMEN

Past and contemporary human actions are causing numerous changes in patterns and processes at various ecosystem scales and trophic levels, including unintended downstream changes, such as species interactions. In its native range Acca sellowiana (Feijoa) combines some characteristics of human interactions: incipient domestication, restricted to subtropical Atlantic Forest highlands, associated with the threatened conifer Araucaria angustifolia (Araucaria), within a domesticated landscape with anthropogenic forest patches, and provides fruit at a time of resource shortage (Araucaria seeds-pinhão). We quantify the trophic relationships between Feijoa and vertebrates, and evaluate the influences on interactions caused by environmental variations, Feijoa domestication evidences, spatial distance and fruit availability. In four sites within protected areas, we selected 28 focal individuals of Feijoa (seven/site) and collected three temporal replicas between 2015 and 2016, when we measured productivity and frugivory via 45-second videos taken with camera traps. Using ecological network, rarefaction curves and variation partitioning analyses, we evaluate the frugivory network topology, the spatiotemporal structure of communities in relation to fruit availability and the influence of predictive variables on frugivory. We found a large spatiotemporal variation in productivity of Feijoa and that 20 species consumed Feijoa fruits, with a species degree of 2.8 (±5.7) and average Feijoa degree of 14.4 (±10.1), in a modular network with intermediary connectance. Rarefaction curves showed that richness and the independent records are congruent with the fruit amount. Variation partitioning showed that, for the focal individuals, canopy area, green coverage, patch size and distance to water influenced frugivory, and the Feijoa domestication influenced significantly the mammalian frugivory. Feijoa is an important resource that provides food during the time of year when Pinhão is absent, and attracts frugivores, maintain the residual diversity of vertebrates contributing to the structure of communities in highlands. Our insights allowed us to evaluate the magnitude of the interactions between vertebrates and an incipient domesticated tree, in a cultural landscape and highly threatened environment, under a basal foodweb approach with implications for bottom-up and top-down forces. The results contribute to understanding animal-plant relationships, including concepts that can be replicated for other sessile prey and mobile predators in any region or habitat under different gradients of management. Thus, this work shows how human actions can change not only patterns of distribution and abundance but also the diversity and direction of interspecific interactions among species.


Asunto(s)
Feijoa/fisiología , Vertebrados/fisiología , Animales , Biodiversidad , Domesticación , Ecosistema , Feijoa/crecimiento & desarrollo , Bosques , Frutas/fisiología , Herbivoria
7.
Biota neotrop. (Online, Ed. port.) ; 13(2): 70-75, Apr-Jun/2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-682392

RESUMEN

The Brazilian Pantanal comprises a mosaic of forest and field environments harbouring a rich community of large and midsized mammals that are adapted to the annual hydrological cycle. Here we evaluated richness and composition of large and midsized mammals inhabiting forested and open habitats affected by yearly floods in the Pantanal in Cáceres from October 2009 to September 2010. We compared these communities in marshes, dry forests and riparian forests based on 640 camera-traps.nights, sights, tracks, faecal samples and interviews. We also compared results in a private land (Descalvados Farm) and in a protected area (Taiamã Ecological Station). In total, we sampled 26 large and midsized mammals, including five threatened and two near threatened species. Jaguars, collared peccaries and red-brocket deers were the only mammals recorded at all habitat types, while eleven species were recorded exclusively in one of the habitats. We identified a heterogeneous use of the habitat by the animal community surveyed in all three habitats during the wet and dry season. Furthermore, precipitation and river level affected the use of dry forests and marshes isolated from dry forests. Finally, 62% of large/midsized mammal species present in the surveyed region recorded outside the reserve; therefore, we recommend conservation actions to protect those species and also to preserve unprotected dry forests.


O Pantanal brasileiro é formado por um mosaico de ambientes florestados e campestres, abrigando uma rica comunidade de mamíferos de médio e grande porte adaptados ao ciclo hidrológico anual. Nós avaliamos a riqueza e composição de mamíferos de médio e grande porte em habitats florestados e campestres afetados pelas inundações anuais no Pantanal de Cáceres ente outubro/2009 e setembro/2010. Comparamos as comunidades em Campos Inundáveis, Matas Secas e Matas Ripárias com base em 640 armadilhas-fotográficas.noite, avistamentos, pegadas, amostras fecais e entrevistas. Nós também comparamos os resultados em uma área privada (Fazenda Descalvados) e em uma área protegida (Estação Ecológica Taiamã). No total, foram registradas 26 espécies de mamíferos de médio e grande porte, incluindo cinco espécies ameaçadas de extinção e duas quase ameaçadas. Onças-pintadas, catetos e veados-mateiro foram os únicos mamíferos registrados em todos os habitats, enquanto que 11 espécies foram registradas em apenas um tipo de hábitat. Identificamos diferença quanto ao uso dos habitats entre os três tipos de habitats durante a estação seca e chuvosa. Além disso, a precipitação e o nível do rio afetaram o uso da Mata Seca e Campos Inundáveis isolados das Matas Secas. Por fim, 62% das espécies foram registradas fora da reserva, por isso, recomendamos ações de conservação para proteger as espécies e também para preservar as florestas secas desprotegidas.

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