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  • Wiley  (13)
  • Biodiversitätsforschung  (13)
  • 1
    In: Biotropica, Wiley, Vol. 55, No. 1 ( 2023-01), p. 29-39
    Kurzfassung: Estudos nos Trópicos, tradicionalmente, descrevem a variação na diversidade de insetos ao longo do ano. As respostas temporais das assembleias de insetos a sazonalidade climática variam nos ecossistemas devido a gradientes de disponibilidade de recursos e fatores ecológicos limitantes. Essas respostas podem ocorrer por toda a vasta extensão geográfica do território brasileiro, incluindo vários ambientes que abrigam uma das mais diversas faunas de formigas do mundo. Este estudo abordou a relação entre diversidade de formigas e a sazonalidade climática, através de uma revisão quantitativa dos dados publicados sobre diversidade de formigas coletados no Brasil. Investigamos o efeito da sazonalidade na abundância e na riqueza de formigas descrito na literatura e obtivemos 47 trabalhos publicados entre 2000 e 2018. Esses estudos foram desenvolvidos principalmente no bioma Mata Atlântica, coletaram formigas com armadilhas Pitfall e no estrato solo/serrapilheira. Inicialmente, realizamos o procedimento de contagem de votos comparando o número de resultados significativos que descrevem diferenças sazonais na assembleia de formigas. Encontramos a maioria dos artigos descrevendo um padrão semelhante de abundância, riqueza e composição de espécies de formigas entre as estações. No entanto, quando realizamos uma meta‐análise, observamos um padrão claro de maior abundância e riqueza de formigas na estação chuvosa/verão em comparação com a estação seca/inverno. Nossa meta‐análise revela que a diversidade de formigas diminui na estação seca, especialmente no bioma Cerrado. Adicionalmente, apontamos diferenças no esforço amostral entre biomas, indicando a necessidade de mais estudos focados em padrões de diversidade temporal, incluindo efeitos sazonais, na assembleia de insetos em biomas com menor concentração de estudos.
    Materialart: Online-Ressource
    ISSN: 0006-3606 , 1744-7429
    URL: Issue
    RVK:
    Sprache: Englisch
    Verlag: Wiley
    Publikationsdatum: 2023
    ZDB Id: 2052061-X
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 2
    In: Journal of Ecology, Wiley, Vol. 108, No. 4 ( 2020-07), p. 1578-1591
    Kurzfassung: Information on direct and indirect drivers of temporal variation in ant–plant interactions is scarce, compromising our ability to predict the functioning of these ecologically important interactions. We investigated the roles of precipitation, ant activity, abundance of young plant tissues bearing extrafloral nectaries (EFNs) and EFN phenotypes in the establishment of EFN‐mediated ant–plant interactions throughout the year in Amazonia, Brazil. We hypothesized that the frequency of ant–plant interactions follows a predictable seasonal pattern, being higher in wetter periods, during which plants invest more in the production of new plant tissues bearing EFNs, ultimately promoting ant attendance. We surveyed and tagged every understorey Bignonieae plant rooted inside 28,500‐m 2 plots, and recorded ant–EFN interactions on each plant five times throughout the year. We also sampled ants with honey baits to estimate temporal variation in general ant activity. Contrary to our hypothesis, the proportion of plants tended by ants in each plot was higher in drier, not wetter, months. Ant attendance was indirectly and negatively related to precipitation, which was attributed to a decrease in the proportion of plants producing new EFN‐bearing plant tissues during the wetter period. Additionally, seasonal variation in an ant activity did not explain temporal patterns of plant attendance. At the plant level, ant attendance increased strongly with the number of recently formed shoot nodes, and ants almost never attended plants with limited or no young tissue. Among the 12 most abundant Bignonieae species, the amount of young tissue was the most important predictor of ant attendance, secondarily explained by the EFN secretory area. Synthesis . Our results suggest that seasonal variation in the production of new plant tissues bearing EFNs is the primary driver of the temporal patterns of EFN–plant attendance by ants in this system. Contrary to our expectations, production of new plant tissue is higher in the drier months of the year, which in turn boosts the frequency of interactions between ants and EFN‐bearing plants in the dry season. These results highlight the role of plant phenology in the remarkable variation encountered in ant visitation to EFN‐bearing plants in both space and time.
    Materialart: Online-Ressource
    ISSN: 0022-0477 , 1365-2745
    URL: Issue
    Sprache: Englisch
    Verlag: Wiley
    Publikationsdatum: 2020
    ZDB Id: 3023-5
    ZDB Id: 2004136-6
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 3
    In: Entomologia Experimentalis et Applicata, Wiley, Vol. 167, No. 6 ( 2019-06), p. 534-543
    Kurzfassung: Methods to quantify plant‐insect interactions in tropical forests may miss many important arthropods and can be time consuming and uneven in capture efficiency. We describe the Amazonas‐trap, a new method that rapidly envelops the target plant for sampling arthropods. We evaluated the efficiency of the Amazonas‐trap by comparing it with two commonly used sampling methods to collect arthropods from plants: the beating tray and manual collection. Samples were collected in 10 permanent plots, in the Ducke forest reserve, Manaus (Amazonas, Brazil). In each plot we sampled 18 plant individuals of Protium sp. (Burseraceae): six by a beating tray, six by manual collection, and six using the Amazonas‐trap. All insects were identified to the family level and those belonging to the order Hymenoptera were identified to the species and morphospecies level. The new method sampled more insect families and more Hymenoptera species than tree beating and manual collection. Of the 75 total families collected, 20 were sampled exclusively by the Amazonas‐trap, seven were only collected with a beating tray, and seven were sampled exclusively with manual collecting. A similar pattern was found for abundance: Amazonas‐trap sampled more individuals, followed by the beating tray and manual collection. Small and winged arthropods were more abundant in Amazonas‐trap, explaining the highest richness of Hymenoptera and insect families sampled with this method. The new method sampled more spiders, wood‐fungi feeders, sap suckers, omnivorous, parasitoids, and insect predators than the other methods, but was equally effective in sampling leaf‐feeders and ants. Amazonas‐trap was more time consuming in the field, but for all diversity parameters evaluated, the new method showed better performance for collecting invertebrates on plants.
    Materialart: Online-Ressource
    ISSN: 0013-8703 , 1570-7458
    URL: Issue
    RVK:
    Sprache: Englisch
    Verlag: Wiley
    Publikationsdatum: 2019
    ZDB Id: 2015286-3
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 4
    In: Journal of Biogeography, Wiley, Vol. 49, No. 2 ( 2022-02), p. 324-338
    Kurzfassung: Current diversity patterns in local communities result from historical and contemporary events that operate at distinct spatial and temporal scales. However, the contribution of local and large‐scale processes in structuring species diversity remain a contentious topic in ecology. We investigated diversity patterns (species richness, composition and number of captures) of understorey bird assemblages in Amazonian unflooded ( terra firme ) forests. We sought to understand whether understorey bird assemblages in distinct areas of endemism show distinct patterns of diversity, and whether species replacements among areas of endemism occur while the proportion of species within guilds remains stable. Location Amazonia. Taxon Understorey birds. Methods To investigate diversity patterns, we compiled studies that mist‐netted birds at 11 regions across seven Amazonian areas of endemism. We used coverage‐based rarefaction curves, non‐metric multidimensional scaling (NMDS) and created a heatmap based on the proportion of captures in each area of endemism to access patterns of richness, composition and captures of understorey birds, respectively. The relative variance (RVgp index) was calculated to investigate the existence of guild proportionality within each area of endemism. Results Bird assemblages diverged across the seven areas of endemism, in terms of species richness, composition and captures. However, the proportion of species and individuals within guilds was similar among areas of endemism, indicating that species replacements across areas of endemism occur while maintaining the same ecological functions. Guild proportionality suggests that interspecific competition and resource availability are more important than environmental heterogeneity in structuring understorey bird assemblages. Main conclusions The similar proportion of species within guilds suggest that interspecific competition and resource availability are more important than environmental heterogeneity in structuring local assemblages, possibly via a process of limiting similarity in morphological and functional traits. The observed congruent structure in understorey bird assemblages across areas of endemism shows that coupled historical and ecological processes, operating at local to large scales, have led to current patterns of diversity and composition in Amazonian bird communities.
    Materialart: Online-Ressource
    ISSN: 0305-0270 , 1365-2699
    URL: Issue
    Sprache: Englisch
    Verlag: Wiley
    Publikationsdatum: 2022
    ZDB Id: 2020428-0
    ZDB Id: 188963-1
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 5
    In: Biotropica, Wiley, Vol. 52, No. 6 ( 2020-11), p. 1275-1285
    Kurzfassung: Optimal foraging theory predicts that animals will seek simultaneously to minimize food processing time and maximize energetic gain. To test this hypothesis, we evaluated whether a specialist seed‐predator primate forages optimally when choosing among variable‐sized thick‐husked fruits. Our objects of study were the golden‐backed uacari ( Cacajao ouakary , Pitheciidae) and single‐seeded pods of the macucu tree ( Aldina latifolia , Fabaceae). We predict that golden‐backed uacari will consume fruits of the size class that requires the least time to obtain, handle, and ingest. We used scan sampling, ad libitum to record feeding observations, and measured fruits, their penetrability, and the size of taxidermized C. ouakary hands. To test whether uacaris selected for optimal characteristics, we compared 8 metrics from 75 eaten and 105 uneaten seeds/fruits collected. Uacaris selected fruits of medium size and weight disproportionately to their abundance. Processing large fruits took six times longer than did medium‐sized fruits, but seeds were only four times as large, that is, for energetic yield per unit time, thus choosing medium‐sized pods was optimal. Disproportionate selection by C. ouakary of fruits of medium size and mass in relation to their abundance suggests active sub‐sampling of the available weight–size continuum. This selectivity probably maximizes trade‐offs between the energy derived from a seed, and time and energy expended in processing fruit to access this, so following optimal foraging theory predictions. The greater time spent processing large pods is attributed to difficulties manipulating objects five to seven times the size of the animal's palm and one‐sixth its own body weight.
    Materialart: Online-Ressource
    ISSN: 0006-3606 , 1744-7429
    URL: Issue
    RVK:
    Sprache: Englisch
    Verlag: Wiley
    Publikationsdatum: 2020
    ZDB Id: 2052061-X
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 6
    In: Biotropica, Wiley, Vol. 45, No. 6 ( 2013-11), p. 755-763
    Materialart: Online-Ressource
    ISSN: 0006-3606
    URL: Issue
    RVK:
    Sprache: Englisch
    Verlag: Wiley
    Publikationsdatum: 2013
    ZDB Id: 2052061-X
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 7
    In: Ecology, Wiley, Vol. 98, No. 3 ( 2017-03), p. 883-884
    Kurzfassung: What forces structure ecological assemblages? A key limitation to general insights about assemblage structure is the availability of data that are collected at a small spatial grain (local assemblages) and a large spatial extent (global coverage). Here, we present published and unpublished data from 51 ,388 ant abundance and occurrence records of more than 2,693 species and 7,953 morphospecies from local assemblages collected at 4,212 locations around the world. Ants were selected because they are diverse and abundant globally, comprise a large fraction of animal biomass in most terrestrial communities, and are key contributors to a range of ecosystem functions. Data were collected between 1949 and 2014, and include, for each geo‐referenced sampling site, both the identity of the ants collected and details of sampling design, habitat type, and degree of disturbance. The aim of compiling this data set was to provide comprehensive species abundance data in order to test relationships between assemblage structure and environmental and biogeographic factors. Data were collected using a variety of standardized methods, such as pitfall and Winkler traps, and will be valuable for studies investigating large‐scale forces structuring local assemblages. Understanding such relationships is particularly critical under current rates of global change. We encourage authors holding additional data on systematically collected ant assemblages, especially those in dry and cold, and remote areas, to contact us and contribute their data to this growing data set.
    Materialart: Online-Ressource
    ISSN: 0012-9658 , 1939-9170
    URL: Issue
    RVK:
    Sprache: Englisch
    Verlag: Wiley
    Publikationsdatum: 2017
    ZDB Id: 1797-8
    ZDB Id: 2010140-5
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 8
    In: Journal of Ecology, Wiley, Vol. 104, No. 5 ( 2016-09), p. 1335-1346
    Kurzfassung: A negative relationship between stand biomass and the density of stems is expected to develop during the self‐thinning process in resource‐limited forests; this leads to a large proportion of the total biomass occurring in large trees. Nevertheless, frequent disturbance regimes can reduce self‐thinning and the accumulation of large trees. We investigated size–density relationships and the contribution of large trees (dbh ≥ 70 cm) to stand biomass in 55 1‐ha plots along a 600 km transect in central‐southern Amazonia. The effects of natural‐disturbance gradients (frequency of storms and soil characteristics) and seasonality on forest‐structure components (density of stems and mean individual mass) and stand biomass were examined. Contrary to self‐thinning predictions, stand biomass increased in forests with higher stem densities. Large trees contained only an average of 5% of stand biomass, and half of the stand biomass was represented by small trees with diameters 〈  27 cm. These findings indicate that persistent or strong disturbance plays a critical role in forest structure and biomass in the central‐southern Amazon. Frequent storms were identified as an important source of disturbance in the region. Forests under higher frequency of storms had trees with lower individual mass and higher stem packing. More physically restrictive soils seem to magnify the effects of exogenous disturbances limiting individual tree size. Forests in areas with longer dry seasons had lower stem densities; however, individual mass was higher in these areas. These structural components of biomass seem to counterbalance each other in generating total stand biomass. Seasonality affected forest structural components but not stand biomass. Synthesis . Forests of central‐southern Amazonia are not resource limited and accumulate most part of their biomass in small‐ to mid‐sized trees. The effects of environmental gradients on specific structural components of stand biomass differ such that strong positive effects on one component can mitigate strong negative effects on other component. Future work on the determinants of stand biomass should investigate forest structure and the contributions of individual components to stand biomass.
    Materialart: Online-Ressource
    ISSN: 0022-0477 , 1365-2745
    URL: Issue
    Sprache: Englisch
    Verlag: Wiley
    Publikationsdatum: 2016
    ZDB Id: 3023-5
    ZDB Id: 2004136-6
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 9
    In: Global Change Biology, Wiley, Vol. 24, No. 10 ( 2018-10), p. 4614-4625
    Kurzfassung: The relationship between levels of dominance and species richness is highly contentious, especially in ant communities. The dominance‐impoverishment rule states that high levels of dominance only occur in species‐poor communities, but there appear to be many cases of high levels of dominance in highly diverse communities. The extent to which dominant species limit local richness through competitive exclusion remains unclear, but such exclusion appears more apparent for non‐native rather than native dominant species. Here we perform the first global analysis of the relationship between behavioral dominance and species richness. We used data from 1,293 local assemblages of ground‐dwelling ants distributed across five continents to document the generality of the dominance‐impoverishment rule, and to identify the biotic and abiotic conditions under which it does and does not apply. We found that the behavioral dominance–diversity relationship varies greatly, and depends on whether dominant species are native or non‐native, whether dominance is considered as occurrence or relative abundance, and on variation in mean annual temperature. There were declines in diversity with increasing dominance in invaded communities, but diversity increased with increasing dominance in native communities. These patterns occur along the global temperature gradient. However, positive and negative relationships are strongest in the hottest sites. We also found that climate regulates the degree of behavioral dominance, but differently from how it shapes species richness. Our findings imply that, despite strong competitive interactions among ants, competitive exclusion is not a major driver of local richness in native ant communities. Although the dominance‐impoverishment rule applies to invaded communities, we propose an alternative dominance‐diversification rule for native communities.
    Materialart: Online-Ressource
    ISSN: 1354-1013 , 1365-2486
    URL: Issue
    Sprache: Englisch
    Verlag: Wiley
    Publikationsdatum: 2018
    ZDB Id: 2020313-5
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 10
    In: Journal of Biogeography, Wiley, Vol. 45, No. 6 ( 2018-06), p. 1345-1354
    Kurzfassung: Disturbances are events that influence the structure of biological assemblages, yet how historical disturbances have affected the functional structure of recent assemblages is still poorly known. We used species functional traits to investigate the effects of historical disturbances, such as past climate change (aridification), on the current structure of stream fish assemblages. Location Amazon Basin and Brazilian Northeast streams. Methods We used measures of functional specialization and originality to assess the effects of historical disturbances on the structure of fish assemblages in streams with similar local environmental conditions in each biome (Amazonia and Caatinga). For this, we measured 15 traits related to locomotion, feeding and habitat use for each species sampled. We then compared the functional structure of each assemblage expressed as functional richness (FRic) and evenness (FEve) between biomes. We also used structured and random simulations of species extinctions to identify the influence of the loss of original and specialized species due to historical disturbance. Results We found high levels of functional specialization in Amazonia (historically more stable) and redundancy in Caatinga (higher frequency of historical disturbances) regional assemblages, regardless of the inter‐biome differences in species richness. These results were also detected in local assemblages, suggesting that the effect of historical disturbances influences the structure of fish assemblages, both at small and large spatial scales. Main conclusions The historical stability in Amazonian fish assemblages may have favoured a higher taxonomic and FRic, as well as greater functional specialization and originality, compared to Caatinga assemblages. Our results reinforce the importance of understanding and evaluating the evolutionary history of ecosystems in order to describe the current functional structure of species assemblages.
    Materialart: Online-Ressource
    ISSN: 0305-0270 , 1365-2699
    URL: Issue
    Sprache: Englisch
    Verlag: Wiley
    Publikationsdatum: 2018
    ZDB Id: 2020428-0
    ZDB Id: 188963-1
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
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