- I am graduate in Biological Sciences at the Universidade Federal de Santa Catarina (1990), master and PhD in Ecology ... moreI am graduate in Biological Sciences at the Universidade Federal de Santa Catarina (1990), master and PhD in Ecology at the Universidade Estadual de Campinas (1994 and 1998) and post-doctorate at the CSIRO-Australia (2010 and 2014). Since 2002 I am professor at the Universidade Federal de Pernambuco advising under-graduate students from Biological Sciences and Environmental Sciences courses, and post-graduate students from Plant Biology and Animal Biology courses. I have focused my research in understanding how anthropogenic disturbances influence plant-animal interactions. I conduct my research at the two most important ecosystems of northeast Brazil, the humid Atlantic forest and the semiarid Caatinga vegetation, both highly altered by human activities. At the Atlantic forest I have investigated how habitat loss and fragmentation promote herbivore proliferation, especially of leaf-cutting ants, and simplifies other plant-ant interactions. At the Caatinga vegetation my studies involve the effect of chronic anthropogenic disturbances on plant and animal community diversity and structure, and plant-herbivore-ant interactions. My profile in Researcher ID: http://www.researcherid.com/rid/E-8362-2010edit
Introduction Evolutionary traits acquired in response to one type of disturbance will potentially confer resilience to other disturbances that have similar environmental impacts, even if the biota has no evolutionary history of such... more
Introduction Evolutionary traits acquired in response to one type of disturbance will potentially confer resilience to other disturbances that have similar environmental impacts, even if the biota has no evolutionary history of such disturbances. In grassy ecosystems the environmental impacts of grazing have important similarities to those of fire through the removal of grass biomass, and we hypothesise that high resilience to frequent fire confers high resilience to grazing. Aims We test this hypothesis by investigating the resilience of highly fire-resilient ant communities to grazing in a mesic Australian savanna, which has not historically experienced such high levels of mammalian grazing. Methods We sampled ants using pitfall traps at Annaburroo Station in the Australian seasonal tropics using ten plot triplets, with each triplet representing no, low and heavy grazing. Grazing has had a major impact on the basal area of perennial grasses and the cover of bare ground. We conside...
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Despite the outstanding diversity and ecological relevance of ants in most terrestrial ecosystems, current knowledge of the ants of the Caatinga is still incipient. This chapter offers an overview covering the diversity, taxonomy,... more
Despite the outstanding diversity and ecological relevance of ants in most terrestrial ecosystems, current knowledge of the ants of the Caatinga is still incipient. This chapter offers an overview covering the diversity, taxonomy, biogeography, and functional composition of the Caatinga ant fauna, and a synthesis on ant response to chronic anthropogenic disturbance and increased aridity. We compiled a database consisting of 572 presence–absence ant records and 276 ant species from 37 localities in the Caatinga. As expected, most of the Caatinga has not been intensively sampled for ants, with the intensive sampling that has been conducted revealing high rates of species turnover across localities. Most ant species recorded in the Caatinga are widely distributed in other biomes, especially in Cerrado, and few species can be considered endemic to the Caatinga. Thus, the Caatinga ant fauna appears to represent an impoverished subset of the Cerrado’s fauna. Such a reduced endemism and the occurrence of a highly depauperate ant fauna at a regional level contrast to the diversity patterns exhibited by the Caatinga flora and other faunal groups. Significant changes in ant taxonomic and functional composition in response to human disturbance are observed, with a predictable winner–loser replacement. Disturbance winners consist of generalist species exhibiting wide environmental tolerances and those inhabiting open habitats (Opportunists and Dominant Dolichoderinae). Highly specialized species are disturbance losers (Specialist predators). Aridity also affects both species occurrence and functional-group composition of local assemblages. Since several ant species and functional groups are sensitive to increasing disturbance and aridity, ant-mediated ecological services are already threatened in the Caatinga biota.
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Seasonally dry tropical forests (SDTFs) provide a habitat for a diverse number of species and cover significant land areas. Yet, the amount of scientific research they have attracted is minimal. Recently, an international debate on the... more
Seasonally dry tropical forests (SDTFs) provide a habitat for a diverse number of species and cover significant land areas. Yet, the amount of scientific research they have attracted is minimal. Recently, an international debate on the generality, consequences and forces keeping SDTFs in a position of relative negligence has begun. This paper assesses and compares biodiversity-related knowledge across the major Brazilian ecosystems to verify in which extent the Caatinga vegetation (a mosaic of scrubs and patches of seasonally dry forest) has been scientifically unappreciated. In fact, Caatinga attracted the lowest scores from semi-quantitative indexes describing biodiversity-survey efforts and knowledge status, with a negligible number of papers published internationally. Caatinga also supports fewer research teams and senior researchers as compared to humid tropical forests (Amazonia and Atlantic Forest). Both the knowledge index and number of published papers were explained by a m...
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Habitat fragmentation studies have produced complex results that are challenging to synthesize. Inconsistencies among studies may result from variation in the choice of landscape metrics and response variables, which is often compounded... more
Habitat fragmentation studies have produced complex results that are challenging to synthesize. Inconsistencies among studies may result from variation in the choice of landscape metrics and response variables, which is often compounded by a lack of key statistical or methodological information. Collating primary datasets on biodiversity responses to fragmentation in a consistent and flexible database permits simple data retrieval for subsequent analyses. We present a relational database that links such field data to taxonomic nomenclature, spatial and temporal plot attributes, and environmental characteristics. Field assessments include measurements of the response(s) (e.g., presence, abundance, ground cover) of one or more species linked to plots in fragments within a partially forested landscape. The database currently holds 9830 unique species recorded in plots of 58 unique landscapes in six of eight realms: mammals 315, birds 1286, herptiles 460, insects 4521, spiders 204, othe...
Research Interests: Bioinformatics, Landscape Ecology, Conservation Biology, Forest Ecology And Management, Biology, and 15 moreEcology, Forest Fragmentation, Biodiversity, Medicine, Landscape metrics, Global change, Environmental Sciences, Edge effects, Data Sharing, Ecology and Evolution, Habitat fragmentation, Evolution and Ecology, Habitat Fragmentation and Loss, Database, and Forest fragments
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Abstract. 1. The role played by Atta species as ecosystem engineers remains poorly investigated despite previous evidence that their nests can impact plant assemblages. 2. In a large remnant of Atlantic forest, we compared forest... more
Abstract. 1. The role played by Atta species as ecosystem engineers remains poorly investigated despite previous evidence that their nests can impact plant assemblages. 2. In a large remnant of Atlantic forest, we compared forest structure at 36 Atta cephalotes nests to control sites ...
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Leaf-cutting ants as ecosystem engineers:
Seasonally dry tropical forests are characterized by several months of drought. Cenostigma microphyllum is a native woody species widely found in a seasonally dry tropical forest. These forests are in need of restoration and C.... more
Seasonally dry tropical forests are characterized by several months of drought. Cenostigma microphyllum is a native woody species widely found in a seasonally dry tropical forest. These forests are in need of restoration and C. microphyllum is a species that can be used to this end. We studied, 1) acute water deficiency using plant in pot, and 2) chronic water deficiency in field conditions in areas with different rainfall gradients, always with two group of plants: inoculated and non-inoculated with arbuscular mycorrhizal fungus. Acute water deficit levels in previously inoculated and non-inoculated treatments were similar, however, after rehydration, the inoculated potted plants showed faster recovery of water status and gas exchange. In field conditions, on the 120th day, before the beginning of the dry period, 100% of transplanted seedlings survived, while the total plant dry biomass did not differ between the inoculated and control groups. The same patterns emerged across rainf...
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Although extrafloral nectar (EFN) is a key food resource for arboreal ants, its role in structuring ground-nesting ant communities has received little attention, despite these ants also being frequent EFN-attendants. We investigated the... more
Although extrafloral nectar (EFN) is a key food resource for arboreal ants, its role in structuring ground-nesting ant communities has received little attention, despite these ants also being frequent EFN-attendants. We investigated the role of EFN as a driver of the spatial structure of ground-nesting ant communities occurring in dry forest in north-eastern Brazil. We examined the effects on this relationship of two global drivers of biodiversity decline, chronic anthropogenic disturbance and climate change (through decreasing rainfall). We mapped EFN-producing plants and ant nests in 20 plots distributed along independent gradients of disturbance and rainfall. We categorized ant species into three types according to their dependence on EFN: heavy users, occasional users and non-users. We found a strong relationship between ant dependence on EFN and nest proximity to EFN-producing plants: heavy-users (mean distance 1.1 m) nested closer to EFN-producing plants than did occasional us...
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Despite the outstanding diversity and ecological relevance of ants in most terrestrial ecosystems, current knowledge of the ants of the Caatinga is still incipient. This chapter offers an overview covering the diversity, taxonomy,... more
Despite the outstanding diversity and ecological relevance of ants in most terrestrial ecosystems, current knowledge of the ants of the Caatinga is still incipient. This chapter offers an overview covering the diversity, taxonomy, biogeography, and functional composition of the Caatinga ant fauna, and a synthesis on ant response to chronic anthropogenic disturbance and increased aridity. We compiled a database consisting of 572 presence–absence ant records and 276 ant species from 37 localities in the Caatinga. As expected, most of the Caatinga has not been intensively sampled for ants, with the intensive sampling that has been conducted revealing high rates of species turnover across localities. Most ant species recorded in the Caatinga are widely distributed in other biomes, especially in Cerrado, and few species can be considered endemic to the Caatinga. Thus, the Caatinga ant fauna appears to represent an impoverished subset of the Cerrado’s fauna. Such a reduced endemism and th...
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SUMMARY Habitat loss is widely recognized as the major cause of global biodiversity decline, but remaining habitat is increasingly threatened by chronic human disturbances. Using a multi-model averaging approach we examined the... more
SUMMARY Habitat loss is widely recognized as the major cause of global biodiversity decline, but remaining habitat is increasingly threatened by chronic human disturbances. Using a multi-model averaging approach we examined the association between five chronic disturbance surrogates and the richness and taxonomic and functional composition of ants in Brazilian Caatinga. Using pitfall traps in 47 plots near Parnamirim city (Pernambuco) across two soil types (sand and clay), we recorded 53 species from 27 genera. Ant species richness on sand was slightly higher than on clay, and was negatively related to most surrogates of anthropogenic disturbance. Soil type and human population size were the main predictors of ant species richness. Soil type was the most important predictor of functional group abundance. Taxonomic and functional composition were influenced by soil type and disturbance, but this relationship varied between clay and sandy soils. Ant functional composition showed a wea...
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Habitat fragmentation studies have produced complex results that are challenging to synthesize. Inconsistencies among studies may result from variation in the choice of landscape metrics and response variables, which is often compounded... more
Habitat fragmentation studies have produced complex results that are challenging to synthesize. Inconsistencies among studies may result from variation in the choice of landscape metrics and response variables, which is often compounded by a lack of key statistical or methodological information. Collating primary datasets on biodiversity responses to fragmentation in a consistent and flexible database permits simple data retrieval for subsequent analyses. We present a relational database that links such field data to taxonomic nomenclature, spatial and temporal plot attributes, and environmental characteristics. Field assessments include measurements of the response(s) (e.g., presence, abundance, ground cover) of one or more species linked to plots in fragments within a partially forested landscape. The database currently holds 9830 unique species recorded in plots of 58 unique landscapes in six of eight realms: mammals 315, birds 1286, herptiles 460, insects 4521, spiders 204, othe...
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Perturbações antrópicas são consideradas a causa mais importante do declínio da biodiversidade em todo o mundo. Isso também é verdade para a Caatinga, o ecossistema menos estudado e menos protegido do Brasil. Um dos animais mais... more
Perturbações antrópicas são consideradas a causa mais importante do declínio da biodiversidade em todo o mundo. Isso também é verdade para a Caatinga, o ecossistema menos estudado e menos protegido do Brasil. Um dos animais mais pluralísticos nesse bioma são as formigas, responsáveis pelos mais variados serviços ecossistêmicos, os quais vêm sendo cada vez mais estudados pela comunidade científica. No entanto, esses estudos não retornam à sociedade, além da comunidade acadêmica. Em função disso, pesquisadores e estudantes buscaram promover atividades educativas no Parque Nacional do Catimbau para divulgar e conscientizar sobre a biodiversidade e importância ecológica das formigas na Caatinga. As atividades contaram com a apresentação de palestras sobre a importância das formigas com o uso de maquetes do Parque para facilitar a comunicação, distribuição de revistas em quadrinho e cartazes, jogos de tabuleiros, além de amplos debates sobre o assunto. Cerca de 50 estudantes de 10 a 14 a...
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Predicting community responses to disturbance is a major challenge for both ecology and ecosystem management. A particularly challenging issue is that the same type and intensity of disturbance can have different impacts in different... more
Predicting community responses to disturbance is a major challenge for both ecology and ecosystem management. A particularly challenging issue is that the same type and intensity of disturbance can have different impacts in different habitats. We investigate how habitat contingency influences ant community responses to disturbance in arid Australia, testing the hypothesis that disturbance has a greater impact in more complex habitats. We also assess the effectiveness of a highly simplified ant assessment protocol that considers larger species only. We sampled ants at 46 sites from two habitats (Chandler, low chenopod shrubland; and mulga, low woodland) with contrasting complexity, using distance from water as a surrogate for variation in grazing intensity. We assessed variation in habitat structural variables (basal area of perennial grass, and cover of herbs, litter, and bare ground) and ant communities in relation to habitat and distance from water, first using data from the entir...
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Anthropogenic disturbance and climate change are major threats to biodiversity. The Brazilian Caatinga is the world's largest and most diverse type of seasonally dry tropical forest. It is also one of the most threatened, but remains... more
Anthropogenic disturbance and climate change are major threats to biodiversity. The Brazilian Caatinga is the world's largest and most diverse type of seasonally dry tropical forest. It is also one of the most threatened, but remains poorly studied. Here, we analyzed the individual and combined effects of anthropogenic disturbance (three types: livestock grazing, wood extraction, and miscellaneous use of forest resources) and increasing aridity on taxonomic, phylogenetic and functional ant diversity in the Caatinga. We found no aridity and disturbance effects on taxonomic diversity. In spite of this, functional diversity, and to a lesser extent phylogenetic diversity, decreased with increased levels of disturbance and aridity. These effects depended on disturbance type: livestock grazing and miscellaneous resource use, but not wood extraction, deterministically filtered both components of diversity. Interestingly, disturbance and aridity interacted to shape biodiversity response...
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Leafcutter ants propagate co-evolving fungi for food. The nearly 50 species of leafcutter ants (Atta, Acromyrmex) range from Argentina to the USA, with the greatest species diversity in southern South America. We elucidate the... more
Leafcutter ants propagate co-evolving fungi for food. The nearly 50 species of leafcutter ants (Atta, Acromyrmex) range from Argentina to the USA, with the greatest species diversity in southern South America. We elucidate the biogeography of fungi cultivated by leafcutter ants using DNA-sequence and microsatellite-marker analyses of 474 cultivars collected across the leafcutter range. Fungal cultivars belong to two clades (Clade-A, Clade-B). The dominant and widespread Clade-A cultivars form three genotype-clusters, with their relative prevalence corresponding to southern South America, northern South America, and Central & North America. Admixture between Clade-A populations support genetic exchange within a single species, Leucocoprinus gongylophorus. Some leafcutter species that cut grass as fungicultural substrate are specialized to cultivate Clade-B fungi, whereas leafcutters preferring dicot plants appear specialized on Clade-A fungi. Cultivar sharing between sympatric leafcu...
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RESUMO: Áreas degradadas são tipicamente caracterizadas por solos pobres , erodidos, com instabilidade hidrológica,produtividade reduzida, pouca diversidade biológica e alteração das características físicas e químicas. O solo pode sofrer... more
RESUMO: Áreas degradadas são tipicamente caracterizadas por solos pobres , erodidos, com instabilidade hidrológica,produtividade reduzida, pouca diversidade biológica e alteração das características físicas e químicas. O solo pode sofrer erosões onde diversos podem ser os fatores responsáveis, que vão dos mais simples ao mais complexos. A atividade de extração de argila que implica na retirada da vegetação natural e intensa movimentação de solo, gera em alguns casos buracos que contribuem para o distúrbio da área, além de promover com a retirada de nutrientes , alta toxidez de metais no solo. A exploração de argila na cidade de Marabá tem causado uma série de impactos negativos ao meio físico, natural, facilitando o processo de erosão, e o solo apresenta-se erodido, com considerável quantidade de rejeitos, prejudicando também a microbiota do solo. Com esta problemática o projeto “Reabilitação de áreas impactadas por extração de argila através do uso de plantas arbóreas inoculada com...
RESUMO: Áreas degradadas são tipicamente caracterizadas por solos pobres , erodidos, com instabilidade hidrológica,produtividade reduzida, pouca diversidade biológica e alteração das características físicas e químicas. O solo pode sofrer... more
RESUMO: Áreas degradadas são tipicamente caracterizadas por solos pobres , erodidos, com instabilidade hidrológica,produtividade reduzida, pouca diversidade biológica e alteração das características físicas e químicas. O solo pode sofrer erosões onde diversos podem ser os fatores responsáveis, que vão dos mais simples ao mais complexos. A atividade de extração de argila que implica na retirada da vegetação natural e intensa movimentação de solo, gera em alguns casos buracos que contribuem para o distúrbio da área, além de promover com a retirada de nutrientes , alta toxidez de metais no solo. A exploração de argila na cidade de Marabá tem causado uma série de impactos negativos ao meio físico, natural, facilitando o processo de erosão, e o solo apresenta-se erodido, com considerável quantidade de rejeitos, prejudicando também a microbiota do solo. Com esta problemática o projeto “Reabilitação de áreas impactadas por extração de argila através do uso de plantas arbóreas inoculada com...
Aim In this study, we investigate whether anthropogenic land use and habitat fragmentation lead to a process of either homogenization (decreasing spatial replacement and increasing nestedness) or divergence (increasing spatial replacement... more
Aim In this study, we investigate whether anthropogenic land use and habitat fragmentation lead to a process of either homogenization (decreasing spatial replacement and increasing nestedness) or divergence (increasing spatial replacement and decreasing nestedness) of dung beetle assemblages in edge-affected habitats. Location A fragmented landscape of the Atlantic forest of northeast Brazil. Methods We investigate the extent to which beta diversity of dung beetle assemblages varies in edge-affected habitats at different spatial scales (i.e. traps along an interior–exterior nonlinear gradient, within and among habitats). We compare species replacement and nestedness of dung beetle assemblages using (1) multiple dissimilarity measures accounting for compositional heterogeneity across forest (i.e. forest edges, core primary forest areas and small fragments) and matrix habitats (i.e. sugar cane plantations and pastures) and (2) distance matrices accounting for the multivariate structure of dissimilarity. Results (1) Each habitat supported a distinct dung beetle assemblage; (2) there was a strong influence of anthropogenic land use and fragmentation-related effects on dung beetle b-diversity, with species replacements increasing in edge-affected and matrix habitats providing support for the divergence hypothesis at all spatial scales; (3) edge effects enhanced species replacement across assemblages ; (4) dung beetle assemblages were not randomly distributed, with habitat type leading to a strongly nested pattern of species composition; and (5) both dung beetle replacement and nestedness were not correlated with geographic distance, whereby neighbouring sites were not necessarily more similar in their community composition. Main conclusions Species replacement is strongly influenced by habitat configuration and b-diversity increases in edge-affected habitats. Accordingly, anthro-pogenic land use and habitat fragmentation clearly promote community-level taxonomic divergence in human-modified landscapes. Landscape-scale divergence likely results from a non-random distribution of both forest-dependent and disturbance-adapted species across all habitats, which are in marked contrast in terms of suitability.