Publications by authors named "Inara R Leal"

22 Publications

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Plastome evolution in the Caesalpinia group (Leguminosae) and its application in phylogenomics and populations genetics.

Planta 2021 Jul 8;254(2):27. Epub 2021 Jul 8.

Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Recife, Brazil.

Main Conclusion: The chloroplast genomes of Caesalpinia group species are structurally conserved, but sequence level variation is useful for both phylogenomic and population genetic analyses. Variation in chloroplast genomes (plastomes) has been an important source of information in plant biology. The Caesalpinia group has been used as a model in studies correlating ecological and genomic variables, yet its intergeneric and infrageneric relationships are not fully solved, despite densely sampled phylogenies including nuclear and plastid loci by Sanger sequencing. Here, we present the de novo assembly and characterization of plastomes from 13 species from the Caesalpinia group belonging to eight genera. A comparative analysis was carried out with 13 other plastomes previously available, totalizing 26 plastomes and representing 15 of the 26 known Caesalpinia group genera. All plastomes showed a conserved quadripartite structure and gene repertoire, except for the loss of four ndh genes in Erythrostemon gilliesii. Thirty polymorphic regions were identified for inter- or intrageneric analyses. The 26 aligned plastomes were used for phylogenetic reconstruction, revealing a well-resolved topology, and dividing the Caesalpinia group into two fully supported clades. Sixteen microsatellite (cpSSR) loci were selected from Cenostigma microphyllum for primer development and at least two were cross-amplified in different Leguminosae subfamilies by in vitro or in silico approaches. Four loci were used to assess the genetic diversity of C. microphyllum in the Brazilian Caatinga. Our results demonstrate the structural conservation of plastomes in the Caesalpinia group, offering insights into its systematics and evolution, and provides new genomic tools for future phylogenetic, population genetics, and phylogeographic studies.
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http://dx.doi.org/10.1007/s00425-021-03655-8DOI Listing
July 2021

Winner-Loser Species Replacements in Human-Modified Landscapes.

Trends Ecol Evol 2021 06 5;36(6):545-555. Epub 2021 Mar 5.

Departamento de Botânica, Universidade Federal de Pernambuco, Avenida Professor Moraes Rego, s/n, Cidade Universitária, 50670-901 Recife, PE, Brazil.

Community assembly arguably drives the provision of ecosystem services because they critically depend on which and how species coexist. We examine conspicuous cases of 'winner and loser' replacements (WLRs) in tropical forests to provide a framework integrating drivers, impacts on ecological organization, and reconfiguration of ecosystem service provisioning. Most WLRs involve native species and result from changes in resource availability rather than from altered competition among species. In this context, species dispersal is a powerful force controlling community (re)assembly. Furthermore, replacements imply a nearly complete functional reorganization of assemblages and new 'packages' of ecosystem services and disservices provided by winners. WLRs can thus elucidate the multiple transitions experienced by tropical forests, and have theoretical/applied implications, including the role that human-modified landscapes may play in global-scale sustainability.
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http://dx.doi.org/10.1016/j.tree.2021.02.006DOI Listing
June 2021

Designing optimal human-modified landscapes for forest biodiversity conservation.

Ecol Lett 2020 Sep 15;23(9):1404-1420. Epub 2020 Jun 15.

Agroecology, Dept. of Crop Sciences, Centre of Biodiversity and Sustainable Land Use (CBL), University of Goettingen, Göttingen, Germany.

Agriculture and development transform forest ecosystems to human-modified landscapes. Decades of research in ecology have generated myriad concepts for the appropriate management of these landscapes. Yet, these concepts are often contradictory and apply at different spatial scales, making the design of biodiversity-friendly landscapes challenging. Here, we combine concepts with empirical support to design optimal landscape scenarios for forest-dwelling species. The supported concepts indicate that appropriately sized landscapes should contain ≥ 40% forest cover, although higher percentages are likely needed in the tropics. Forest cover should be configured with c. 10% in a very large forest patch, and the remaining 30% in many evenly dispersed smaller patches and semi-natural treed elements (e.g. vegetation corridors). Importantly, the patches should be embedded in a high-quality matrix. The proposed landscape scenarios represent an optimal compromise between delivery of goods and services to humans and preserving most forest wildlife, and can therefore guide forest preservation and restoration strategies.
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http://dx.doi.org/10.1111/ele.13535DOI Listing
September 2020

The ecosystem services provided by social insects: traits, management tools and knowledge gaps.

Biol Rev Camb Philos Soc 2020 10 11;95(5):1418-1441. Epub 2020 Jun 11.

LIHo - Laboratorio Ecotono, INIBIOMA-CONICET-Universidad Nacional del Comahue, Pasaje Gutiérrez 1125, Bariloche, 8400, Argentina.

Social insects, i.e. ants, bees, wasps and termites, are key components of ecological communities, and are important ecosystem services (ESs) providers. Here, we review the literature in order to (i) analyse the particular traits of social insects that make them good suppliers of ESs; (ii) compile and assess management strategies that improve the services provided by social insects; and (iii) detect gaps in our knowledge about the services that social insects provide. Social insects provide at least 10 ESs; however, many of them are poorly understood or valued. Relevant traits of social insects include high biomass and numerical abundance, a diversity of mutualistic associations, the ability to build important biogenic structures, versatile production of chemical defences, the simultaneous delivery of several ESs, the presence of castes and division of labour, efficient communication and cooperation, the capacity to store food, and a long lifespan. All these characteristics enhance social insects as ES providers, highlighting their potential, constancy and efficiency as suppliers of these services. In turn, many of these traits make social insects stress tolerant and easy to manage, so increasing the ESs they provide. We emphasise the need for a conservation approach to the management of the services, as well as the potential use of social insects to help restore habitats degraded by human activities. In addition, we stress the need to evaluate both services and disservices in an integrated way, because some species of social insects are among the most problematic invasive species and native pests. Finally, we propose two areas of research that will lead to a greater and more efficient use of social insects as ES providers, and to a greater appreciation of them by producers and decision-makers.
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http://dx.doi.org/10.1111/brv.12616DOI Listing
October 2020

Support for the habitat amount hypothesis from a global synthesis of species density studies.

Ecol Lett 2020 Apr 11;23(4):674-681. Epub 2020 Feb 11.

Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada.

Decades of research suggest that species richness depends on spatial characteristics of habitat patches, especially their size and isolation. In contrast, the habitat amount hypothesis predicts that (1) species richness in plots of fixed size (species density) is more strongly and positively related to the amount of habitat around the plot than to patch size or isolation; (2) habitat amount better predicts species density than patch size and isolation combined, (3) there is no effect of habitat fragmentation per se on species density and (4) patch size and isolation effects do not become stronger with declining habitat amount. Data on eight taxonomic groups from 35 studies around the world support these predictions. Conserving species density requires minimising habitat loss, irrespective of the configuration of the patches in which that habitat is contained.
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http://dx.doi.org/10.1111/ele.13471DOI Listing
April 2020

Divergent responses of plant reproductive strategies to chronic anthropogenic disturbance and aridity in the Caatinga dry forest.

Sci Total Environ 2020 Feb 23;704:135240. Epub 2019 Nov 23.

Departamento de Botânica, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil. Electronic address:

Anthropogenic disturbance and climate change are major threats to biodiversity persistence and functioning of many tropical ecosystems. Although increases in the intensity of anthropogenic disturbance and climate change are associated with reduced taxonomic, phylogenetic and functional diversities of several organisms, little is known about how such pressures interfere with the distribution of plant reproductive traits in seasonally dry tropical forests. Here we test the hypothesis that individual and combined effects of increasing chronic anthropogenic disturbance and water deficit negatively affect the richness, abundance and diversity of specialized reproductive strategies of native woody plants in the Caatinga dry forest. This study was carried out at the Catimbau National Park, northeastern Brazil (62,294 ha). Chronic anthropogenic disturbance intensity was measured through different sources of disturbance (cattle/goat herbivory, wood extraction, and other people pressures). Water deficit data was obtained from hydrological maps and used as a proxy of aridity. We constructed generalized linear models and selected best-supported models for richness, abundance and functional diversity of reproductive traits. We documented that richness and abundance of plants with certain reproductive traits, regardless the specialization, can increase (in 18 out of the 49 trait categories analyzed; e.g. obligatory cross-pollination in response to increases in aridity and wood extraction), be impaired (in 20 categories; e.g. pollination by Sphingids/beetles with increase in aridity), or remain unchanged (in 21 categories; e.g. pollination by vertebrates with increases in chronic anthropogenic disturbance and aridity) with higher disturbance and aridity. There were combined effects of chronic anthropogenic disturbance and aridity on the richness of plants in nine traits (e.g. pollen flowers; dioecious and self-incompatible plants). Aridity affected 40% of the reproductive traits, while chronic anthropogenic disturbance affected 35.5%. The functional diversity of reproductive traits was affected only by disturbance. Changes in plant community structure promoted by chronic anthropogenic disturbance and aridity will likely threaten plant-animal interactions, thereby compromising the functioning of communities and the persistence of biodiversity in the Caatinga.
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http://dx.doi.org/10.1016/j.scitotenv.2019.135240DOI Listing
February 2020

Effects of increasing aridity and chronic anthropogenic disturbance on seed dispersal by ants in Brazilian Caatinga.

J Anim Ecol 2019 06 10;88(6):870-880. Epub 2019 Apr 10.

Departamento de Botânica, Universidade Federal de Pernambuco, Recife, PE, Brazil.

Anthropogenic disturbance and climate change are the main drivers of biodiversity loss and ecological services around the globe. There is concern that climate change will exacerbate the impacts of disturbance and thereby promote biotic homogenization, but its consequences for ecological services are unknown. We investigated the individual and interactive effects of increasing chronic anthropogenic disturbance (CAD) and aridity on seed dispersal services provided by ants in Caatinga vegetation of north-eastern Brazil. The study was conducted in Catimbau National Park, Pernambuco, Brazil. Within an area of 214 km , we established nineteen 50 × 20 m plots that encompassed gradients of both CAD and aridity. We offered diaspores of six plant species, three myrmecochorous diaspores and three fleshy fruits that are secondarily dispersed by ants. We then quantified the number of interactions, seed removal rate and dispersal distances, and noted the identities of interacting ant species. Finally, we used pitfall trap data to quantify the abundances of ant disperser species in each plot. Our results show that overall composition of ant disperser species varied along the gradients of CAD and aridity, but the composition of high-quality dispersers varied only with aridity. The total number of interactions, rates of removal and mean distance of removal all declined with increasing aridity, but they were not related to CAD. These same patterns were found when considering only high-quality disperser species, driven by the responses of the dominant disperser Dinoponera quadriceps. We found little evidence of interactive effects of CAD and aridity on seed dispersal services by ants. Our study indicates that CAD and aridity act independently on ant-mediated seed dispersal services in Caatinga, such that the impacts of anthropogenic disturbance are unlikely to change under the forecast climate of increased aridity. However, our findings highlight the vulnerability of seed dispersal services provided by ants in Caatinga under an increasingly arid climate due to low functional redundancy in high-quality disperser species. Given the large number of plant species dependent on ants for seed dispersal, this has important implications for future plant recruitment and, consequently, for the composition of Caatinga plant communities.
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http://dx.doi.org/10.1111/1365-2656.12979DOI Listing
June 2019

Socioeconomic differences among resident, users and neighbour populations of a protected area in the Brazilian dry forest.

J Environ Manage 2019 Feb 3;232:607-614. Epub 2018 Dec 3.

Departamento de Biociências, Universidade Federal Rural do Semiárido, Av. Francisco Mota, 572, Mossoró, Rio Grande do Norte, Brazil. Electronic address:

Protected areas are an important strategy to safeguard biodiversity. However, if social development is not considered, biological conservation targets may not be achieved. In this empirical study, we assess the relationship between poverty and conservation goals in dry forests within a 62,000-ha Brazilian National Park (Caatinga biome). We conducted 81 structured household interviews between January and July of 2016 to assess socioeconomic, resource management and land-use variables. We used non-parametric analysis of variance to test for differences in socioecological variables among families living inside and outside the Park and both (double dwelling). The majority of families (76%) residing inside the Park were living below the poverty line while less than 14% in outside and double dwelling residences faced the same issue. Families living inside the park had lower socioeconomic conditions such as limited water availability, poor house infrastructure, low income, and high dependence on firewood than outside and double dwelling families. They were also more dependent on external financial support and natural resources. We found that failures in protected areas inception and implementation have driven people towards a mutually reinforcing and declining situation in which negative socioeconomic outcomes are associated with nature degradation. Therefore, our results suggest that the future of dry forests, characterized worldwide by the presence of low-income populations, will be largely dependent on conservation strategies that address poverty alleviation and human well-being.
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http://dx.doi.org/10.1016/j.jenvman.2018.11.101DOI Listing
February 2019

Habitat-contingent responses to disturbance: impacts of cattle grazing on ant communities vary with habitat complexity.

Ecol Appl 2018 10 30;28(7):1808-1817. Epub 2018 Jul 30.

Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, Northern Territory, 0909, Australia.

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 entire ant community and then for larger ants (>4 mm body length) only. Site species richness was almost twice as high in mulga, the more structurally complex habitat, than in Chandler, and ant communities in mulga showed far more variation in relation to distance from water. Litter cover was the key environmental variable associated with the interaction between grazing and habitat: it increased with increasing distance from water in mulga and was virtually absent from Chandler. Analysis of only larger species revealed the same patterns of variation in ant abundance, species richness and composition in relation to habitat and grazing as shown by entire ant communities. Our findings support the hypothesis that disturbance impacts on faunal communities increase with increasing habitat complexity. An appreciation of such habitat contingency is important for a predictive understanding and therefore effective management of disturbances such as rangeland grazing. Our findings also show that simplified assessment can provide robust information on the responses of highly diverse ant communities to disturbance, which enhances their feasibility for use as bio-indicators in land management.
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http://dx.doi.org/10.1002/eap.1770DOI Listing
October 2018

Increased anthropogenic disturbance and aridity reduce phylogenetic and functional diversity of ant communities in Caatinga dry forest.

Sci Total Environ 2018 Aug 16;631-632:429-438. Epub 2018 Mar 16.

Departamento de Botânica, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego s/no, Recife, PE 50670-901, Brazil.

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 responses. While aridity sometimes intensified the negative effects of disturbance, the greatest declines in biodiversity were in the wettest areas. Our results imply that anthropogenic disturbance and aridity interact in complex ways to endanger biodiversity in seasonally dry tropical forests. Given global climate change, neotropical semi-arid areas are habitats of concern, and our findings suggest Caatinga conservation policies must prioritize protection of the wettest areas, where biodiversity loss stands to be the greatest. Given the major ecological relevance of ants, declines in both ant phylogenetic and functional diversity might have downstream effects on ecosystem processes, insect populations, and plant populations.
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http://dx.doi.org/10.1016/j.scitotenv.2018.03.037DOI Listing
August 2018

Effects of chronic anthropogenic disturbance and rainfall on the specialization of ant-plant mutualistic networks in the Caatinga, a Brazilian dry forest.

J Anim Ecol 2018 07 6;87(4):1022-1033. Epub 2018 Apr 6.

Programa de Pós-Graduação em Biologia Vegetal, Universidade Federal de Pernambuco, Recife, Brazil.

Anthropogenic disturbance and climate change might negatively affect the ecosystem services provided by mutualistic networks. However, the effects of such forces remain poorly characterized. They may be especially important in dry forests, which (1) experience chronic anthropogenic disturbances (CADs) as human populations exploit forest resources, and (2) are predicted to face a 22% decline in rainfall under climate change. In this study, we investigated the separate and combined effects of CADs and rainfall levels on the specialization of mutualistic networks in the Caatinga, a seasonally dry tropical forest typical of north-eastern Brazil. More specifically, we examined interactions between plants bearing extrafloral nectaries (EFNs) and ants. We analysed whether differences in network specialization could arise from environmentally mediated variation in the species composition, namely via the replacement of specialist by generalist species. We characterized these ant-plant networks in 15 plots (20 × 20 m) that varied in CAD intensity and mean annual rainfall. We quantified CAD intensity by calculating three indices related to the main sources of disturbance in the Caatinga: livestock grazing (LG), wood extraction (WE) and miscellaneous resource use (MU). We determined the degree of ant-plant network specialization using four metrics: generality, vulnerability, interaction evenness and H '. Our results indicate that CADs differentially influenced network specialization: we observed positive, negative, and neutral responses along LG, MU and WE gradients, respectively. The pattern was most pronounced with LG. Rainfall also shaped network specialization, markedly increasing it. While LG and rainfall were associated with changes in network species composition, this trend was not related to the degree of species specialization. This result suggests that shifts in network specialization might be related to changes in species behaviour, not species composition. Our study highlights the vulnerability of such dry forest ant-plant networks to climate change. Moreover, dry forests experience highly heterogeneous anthropogenic disturbances, creating a geographic mosaic of selective forces that may shape the co-evolution of interactions between ants and EFN-bearing plants.
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http://dx.doi.org/10.1111/1365-2656.12820DOI Listing
July 2018

Biogeography of mutualistic fungi cultivated by leafcutter ants.

Mol Ecol 2017 12 2;26(24):6921-6937. Epub 2017 Dec 2.

Centro de Estudos de Insetos Sociais, Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil.

Leafcutter ants propagate co-evolving fungi for food. The nearly 50 species of leafcutter ants (Atta, Acromyrmex) range from Argentina to the United States, 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 and 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, Central and North America. Admixture between Clade-A populations supports 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 leafcutter species occurs frequently such that cultivars of Atta are not distinct from those of Acromyrmex. Leafcutters specialized on Clade-B fungi occur only in South America. Diversity of Clade-A fungi is greatest in South America, but minimal in Central and North America. Maximum cultivar diversity in South America is predicted by the Kusnezov-Fowler hypothesis that leafcutter ants originated in subtropical South America and only dicot-specialized leafcutter ants migrated out of South America, but the cultivar diversity becomes also compatible with a recently proposed hypothesis of a Central American origin by postulating that leafcutter ants acquired novel cultivars many times from other nonleafcutter fungus-growing ants during their migrations from Central America across South America. We evaluate these biogeographic hypotheses in the light of estimated dates for the origins of leafcutter ants and their cultivars.
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http://dx.doi.org/10.1111/mec.14431DOI Listing
December 2017

Phylogenetic impoverishment of plant communities following chronic human disturbances in the Brazilian Caatinga.

Ecology 2016 Jun;97(6):1583-92

Chronic disturbances, such as selective logging, firewood extraction and extensive grazing, may lead to the taxonomic and phylogenetic impoverishment of remaining old-growth forest communities worldwide; however, the empirical evidence on this topic is limited. We tested this hypothesis in the Caatinga vegetation--a seasonally dry tropical forest restricted to northeast Brazil. We sampled 11,653 individuals (adults, saplings, and seedlings) from 51 species in 29 plots distributed along a gradient of chronic disturbance. The gradient was assessed using a chronic disturbance index (CDI) based on five recognized indicators of chronic disturbances: proximity to urban center, houses and roads and the density of both people and livestock. We used linear models to test if mean effective number of lineages, mean phylogenetic distance and phylogenetic dispersion decreased with CDI and if such relationships differed among ontogenetic stages. As expected, the mean effective number of lineages and the mean phylogenetic distance were negatively related to CDI, and such diversity losses occurred irrespective of ontogeny. Yet the increase in phylogenetic clustering in more disturbed plots was only evident in seedlings and saplings, mostly because clades with more descendent taxa than expected by chance (e.g., Euphorbiaceae) thrived in more disturbed plots. This novel study indicates that chronic human disturbances are promoting the phylogenetic impoverishment of the irreplaceable woody flora of the Brazilian Caatinga forest. The highest impoverishment was observed in seedlings and saplings, indicating that if current chronic disturbances remain, they will result in increasingly poorer phylogenetically forests. This loss of evolutionary history will potentially limit the capacity of this ecosystem to respond to human disturbances (i.e., lower ecological resilience) and particularly their ability to adapt to rapid climatic changes in the region.
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http://dx.doi.org/10.1890/15-1122.1DOI Listing
June 2016

Multiple successional pathways in human-modified tropical landscapes: new insights from forest succession, forest fragmentation and landscape ecology research.

Biol Rev Camb Philos Soc 2017 Feb 5;92(1):326-340. Epub 2015 Nov 5.

Departamento de Botânica, Universidade Federal de Pernambuco, Av. Professor Morais Rego, 1235 - Cidade Universitária, Recife, Pernambuco 50670-901, Brazil.

Old-growth tropical forests are being extensively deforested and fragmented worldwide. Yet forest recovery through succession has led to an expansion of secondary forests in human-modified tropical landscapes (HMTLs). Secondary forests thus emerge as a potential repository for tropical biodiversity, and also as a source of essential ecosystem functions and services in HMTLs. Such critical roles are controversial, however, as they depend on successional, landscape and socio-economic dynamics, which can vary widely within and across landscapes and regions. Understanding the main drivers of successional pathways of disturbed tropical forests is critically needed for improving management, conservation, and restoration strategies. Here, we combine emerging knowledge from tropical forest succession, forest fragmentation and landscape ecology research to identify the main driving forces shaping successional pathways at different spatial scales. We also explore causal connections between land-use dynamics and the level of predictability of successional pathways, and examine potential implications of such connections to determine the importance of secondary forests for biodiversity conservation in HMTLs. We show that secondary succession (SS) in tropical landscapes is a multifactorial phenomenon affected by a myriad of forces operating at multiple spatio-temporal scales. SS is relatively fast and more predictable in recently modified landscapes and where well-preserved biodiversity-rich native forests are still present in the landscape. Yet the increasing variation in landscape spatial configuration and matrix heterogeneity in landscapes with intermediate levels of disturbance increases the uncertainty of successional pathways. In landscapes that have suffered extensive and intensive human disturbances, however, succession can be slow or arrested, with impoverished assemblages and reduced potential to deliver ecosystem functions and services. We conclude that: (i) succession must be examined using more comprehensive explanatory models, providing information about the forces affecting not only the presence but also the persistence of species and ecological groups, particularly of those taxa expected to be extirpated from HMTLs; (ii) SS research should integrate new aspects from forest fragmentation and landscape ecology research to address accurately the potential of secondary forests to serve as biodiversity repositories; and (iii) secondary forest stands, as a dynamic component of HMTLs, must be incorporated as key elements of conservation planning; i.e. secondary forest stands must be actively managed (e.g. using assisted forest restoration) according to conservation goals at broad spatial scales.
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http://dx.doi.org/10.1111/brv.12231DOI Listing
February 2017

BIOFRAG - a new database for analyzing BIOdiversity responses to forest FRAGmentation.

Ecol Evol 2014 May 27;4(9):1524-37. Epub 2014 Mar 27.

Departamento de Botânica, Universidade Federal de Pernambuco Recife, Brazil.

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, other arthropods 85, gastropods 70, annelids 8, platyhelminthes 4, Onychophora 2, vascular plants 2112, nonvascular plants and lichens 320, and fungi 449. Three landscapes were sampled as long-term time series (>10 years). Seven hundred and eleven species are found in two or more landscapes. Consolidating the substantial amount of primary data available on biodiversity responses to fragmentation in the context of land-use change and natural disturbances is an essential part of understanding the effects of increasing anthropogenic pressures on land. The consistent format of this database facilitates testing of generalizations concerning biologic responses to fragmentation across diverse systems and taxa. It also allows the re-examination of existing datasets with alternative landscape metrics and robust statistical methods, for example, helping to address pseudo-replication problems. The database can thus help researchers in producing broad syntheses of the effects of land use. The database is dynamic and inclusive, and contributions from individual and large-scale data-collection efforts are welcome.
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http://dx.doi.org/10.1002/ece3.1036DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4063456PMC
May 2014

Myrmecochores can target high-quality disperser ants: variation in elaiosome traits and ant preferences for myrmecochorous Euphorbiaceae in Brazilian Caatinga.

Oecologia 2014 Feb 2;174(2):493-500. Epub 2013 Oct 2.

Programa de Pós-Graduação em Biologia Vegetal, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego s/n, Cidade Universitária, Recife, PE, 50670-901, Brazil.

Recent evidence suggests that the traditional view of myrmecochory as a highly diffuse interaction between diaspores and a wide range of ant species attracted to their elaiosomes may not be correct. The effectiveness of dispersal varies markedly among ant species, and combined with differential attractiveness of diaspores due to elaiosome size and composition, this raises the potential for myrmecochorous plants to target ant species that offer the highest quality dispersal services. We ask the question: Do particular physical and chemical traits of elaiosomes result in disproportionate removal of Euphorbiaceae diaspores by high-quality disperser ants in Caatinga vegetation of north-eastern Brazil? We offered seeds of five euphorb species that varied in morphological and chemical traits of elaiosomes to seed-dispersing ants. High-quality seed-disperser ants (species of Dinoponera, Ectatomma and Camponotus) were identified as those that rapidly collected and transported diaspores to their nests, often over substantial distances, whereas low-quality disperser ants (primarily species of Pheidole and Solenopsis) typically fed on elaiosomes in situ, and only ever transported diaspores very short distances. Low-quality disperser ants were equally attracted to the elaiosomes of all study species. However, high-quality dispersers showed a strong preference for diaspores with the highest elaiosome mass (and especially proportional mass). As far as we are aware, this is the first study to identify a mechanism of diaspore selection by high-quality ant dispersers based on elaiosome traits under field conditions. Our findings suggest that myrmecochorous plants can preferentially target high-quality seed-disperser ants through the evolution of particular elaiosome traits.
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http://dx.doi.org/10.1007/s00442-013-2789-2DOI Listing
February 2014

Germination responses of the invasive Calotropis procera (Ait.) R. Br. (Apocynaceae): comparisons with seeds from two ecosystems in Northeastern Brazil.

An Acad Bras Cienc 2013 Sep;85(3):1025-34

Programa de Pós-Graduação em Biologia Vegetal, Universidade Federal de Pernambuco, Av. Professor Moraes Rego, s/n, Cidade Universitária, 50670-901, Recife PE, Brasil.

Life history traits are considered key indicators of plant invasibility. Among them, the germination behavior of seeds is of major relevance because it is influenced by environmental factors of invaded ecosystem. Here, we investigated how seed traits and seed tolerance to environmental factors on seed germination of Calotropis procera vary depending on the invaded ecosystems in northeastern Brazil. We have tested seeds from two vegetation types - Caatinga and Restinga - to different levels of light intensity, salinity, and water stress. Previous to those experiments, seed-set and morphometric analysis were carried out for both studied populations. We have observed a higher seed-set in Caatinga. Seeds produced in this ecosystem had lower seed moisture content. Seeds from Restinga showed lower germination time when light intensity decreased. We observed a reduction in both the germinability and the synchronization index with decreasing osmotic potential and increasing salinity. Nevertheless, both populations exhibited changes in photoblastism when seeds were submitted to water and saline stress. In conclusion, C. procera seeds are tolerant to environmental factors assessed. That characteristic ensures the colonization success and wide distribution of this plant species in the studied ecosystems.
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http://dx.doi.org/10.1590/S0001-37652013000300013DOI Listing
September 2013

Anthropogenic disturbance reduces seed-dispersal services for myrmecochorous plants in the Brazilian Caatinga.

Oecologia 2014 Jan 30;174(1):173-81. Epub 2013 Jul 30.

Programa de Pós-Graduação em Biologia Vegetal, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego s/n, Cidade Universitária, Recife, PE, 50670-901, Brazil.

Anthropogenic disturbance can have important indirect effects on ecosystems by disrupting species interactions. Here we examine the effects of anthropogenic disturbance on distance dispersal by ants for the diaspores of myrmecochorous Euphorbiaceae in Brazilian Caatinga. Rates of diaspore removal and distances removed of Croton sonderianus and Jatropha mollissima were observed at 24 sites ranging from low to very high disturbance (primarily grazing by livestock, hunting and firewood collection). Despite a large number of seed-disperser ant species, there were only two species providing high-quality distance-dispersal services, Dinoponera quadriceps (40% of all observed seed removals) and Ectatomma muticum (33%). D. quadriceps was responsible for 97% of all removals >2 m, and 100% of all removals >5 m. Removal rates did not vary with disturbance for C. sonderianus (small elaiosome), but declined with increasing disturbance for J. mollissima (large elaiosome). The number of removals by Ectatomma was highest at intermediate levels of disturbance, whereas those by Dinoponera decreased systematically with increasing levels of disturbance. Mean dispersal distance was four times higher at sites experiencing low disturbance, where removals >5 m represented a third of all removal events, compared with very highly disturbed sites, where no removals >5 m were observed. Despite high overall diversity there is very limited functional redundancy in disperser ant species, resulting in low disperser resilience in relation to disturbance. This is likely to have important implications for recruitment by myrmecochorous plants, and therefore on vegetation composition and structure, at sites subject to high anthropogenic disturbance.
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http://dx.doi.org/10.1007/s00442-013-2740-6DOI Listing
January 2014

Community-level patterns of insect herbivory in a fragmented Atlantic forest landscape.

Environ Entomol 2013 Jun;42(3):430-7

Programa de Pós-Graduação em Biologia Vegetal, Universidade Federal de Pernambuco, Recife, Pernambuco, Brasil.

Insect herbivores largely affect plant population structure, community organization, and ecosystem functioning, but little is known on how insect herbivory is altered in human-modified landscapes. Here we assessed 3,566 woody seedlings inhabiting 20 Atlantic forest fragments (3-91 ha) in northeast Brazil to examine the extent to which standing levels of herbivory on woody seedlings correlated with forest fragment metrics (fragment area and distance to forest edge) and resource availability (pioneer plants). Overall, 78% of all seedlings and 36% of the 23,003 recorded leaves experienced injuries caused by folivorous insects, the bulk of them promoted by chewing insects (85.9% of damaged leaves). This insect guild removed 9.2 ± 1.9 cm(2) of foliar tissue per leaf, which represented 10.2 ± 1.8% of the standing leaf area. Contrary to our expectations, frequency and magnitude of foliar damage by insects were statistically uncorrelated to either basic forest fragment metrics (fragment area, edge proximity) or resource abundance (percentage of pioneer seedlings). Our findings indicate that insect herbivory is a pervasive ecological process in fragmented landscapes. However, rather than being a function of simple fragment metrics or resource availability, its variation seems to be caused by a range of drivers, such as dispersal ability of folivorous insects and vulnerability of their parasitoids and predators to human disturbance.
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http://dx.doi.org/10.1603/EN12273DOI Listing
June 2013

[Response of the ant community to attributes of fragments and vegetation in a northeastern Atlantic Rain Forest area, Brazil].

Neotrop Entomol 2010 Nov-Dec;39(6):898-905

Depto de Zoologia, Univ Federal de Pernambuco, Recife, PE, Brasil.

The objective of this study was to determine the effects of forest fragmentation on ant richness in a landscape of Atlantic Forest in Northeast Brazil. More specifically, the ant richness was related to the attributes of fragments (area and distance from the fragment central point to the edge), landscape (forest cover surrounding the fragments), and tree community (plant density, richness, and percentage of shade tolerant species). The surveys were carried out in 19 fragments located in Alagoas State from October 2007 to March 2008. Samples were collected through a 300 m transect established in the center of each fragment, where 30 1-m² leaf litter samples were collected at 10 m intervals. A total of 146 ant species was collected, which belonged to 42 genera, 24 tribes and nine subfamilies. The attributes of fragments and landscape did not influence ant richness. On the other hand, tree density explained ca. 23% of ant richness. In relation to functional groups, both density and richness of trees explained the richness of general myrmicines (the whole model explained ca. 42% of the variation in this group) and percentage of shade tolerant trees explained the richness of specialist predator ants (30% for the whole model). These results indicate that ant fauna is more influenced by vegetation integrity than by fragment size, distance to edge or forest cover surrounding fragments.
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http://dx.doi.org/10.1590/s1519-566x2010000600008DOI Listing
April 2011

Seed dispersal by ants in the semi-arid Caatinga of North-East Brazil.

Ann Bot 2007 May 12;99(5):885-94. Epub 2007 Apr 12.

Departamento de Botânica, Universidade Federal de Pernambuco, 50670-901, Recife, PE, Brazil.

Background And Aims: Myrmecochory is a conspicuous feature of several sclerophyll ecosystems around the world but it has received little attention in the semi-arid areas of South America. This study addresses the importance of seed dispersal by ants in a 2500-km(2) area of the Caatinga ecosystem (north-east Brazil) and investigates ant-derived benefits to the plant through myrmecochory.

Methods: Seed manipulation and dispersal by ants was investigated during a 3-year period in the Xingó region. Both plant and ant assemblages involved in seed dispersal were described and ant behaviour was characterized. True myrmecochorous seeds of seven Euphorbiaceae species (i.e. elaiosome-bearing seeds) were used in experiments designed to: (1) quantify the rates of seed cleaning/removal and the influence of both seed size and elaiosome presence on seed removal; (2) identify the fate of seeds dispersed by ants; and (3) document the benefits of seed dispersal by ants in terms of seed germination and seedling growth.

Key Results: Seed dispersal by ants involved one-quarter of the woody flora inhabiting the Xingó region, but true myrmecochory was restricted to 12.8 % of the woody plant species. Myrmecochorous seeds manipulated by ants faced high levels of seed removal (38-84 %) and 83 % of removed seeds were discarded on ant nests. Moreover, seed removal positively correlated with the presence of elaiosome, and elaiosome removal increased germination success by at least 30 %. Finally, some Euphorbiaceae species presented both increased germination and seedling growth on ant-nest soils.

Conclusions: Myrmecochory is a relevant seed dispersal mode in the Caatinga ecosystem, and is particularly frequent among Euphorbiaceae trees and shrubs. The fact that seeds reach micro-sites suitable for establishment (ant nests) supports the directed dispersal hypothesis as a possible force favouring myrmecochory in this ecosystem. Ecosystems with a high frequency of myrmecochorous plants appear not to be restricted to regions of nutrient-impoverished soil or to fire-prone regions.
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http://dx.doi.org/10.1093/aob/mcm017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2802904PMC
May 2007

[Ant diversity (Hymenoptera: Formicidae) from capões in Brazilian Pantanal: relationship between species richness and structural complexity].

Neotrop Entomol 2006 Nov-Dec;35(6):724-30

Depto. Estudos Básicos e Instrumentais, Univ. Estadual do Sudoeste da Bahia, Itapetinga, BA, 45.700-000.

Species richness of epigeic ants was surveyed in forest islands named capões of Brazilian Pantanal and related with their structural complexity. The ants were collected using pitfall traps in 28 capões from Rio Negro Farm, in Aquidauana municipality, Mato-Grosso do Sul state, Brazil. The structural complexity of capões was evaluated by measuring vegetation density and litter quantity near the pit-fall traps. Seventy-one species, distributed in 26 genera and seven sub-families were found. Ectatomma edentatum Roger (Formicidae: Ectatomminae) and one species of Pheidole were the most frequent species. Species richness was positively correlated only with herbaceous vegetation density of capões, supporting the idea that the increase in environmental heterogeneity diminishes species competition, allowing species co-occurrence.
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http://dx.doi.org/10.1590/s1519-566x2006000600002DOI Listing
June 2007
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