50 research outputs found
Ant Fauna in Megadiverse Mountains: a Checklist for the Rocky Grasslands
The rocky grasslands, environments locally known as campos rupestres, occur mainly along the Espinhaço Mountains and are considered local centers of biodiversity and endemism in Brazil. However, knowledge of ant species richness (Hymenoptera: Formicidae) in this kind of environment is still poor. Aiming at filling this gap, we compiled information from empirical studies and literature records. We found a total of 288 species of 53 genera and eight subfamilies recorded in rocky grasslands. Myrmicinae and Formicinae were the most representative subfamilies, with 53% and 18% of the total species richness, respectively. The genera with the largest number of species were Pheidole (41) and Camponotus (40). This large number of ant species recorded for the rocky grasslands surpasses those found in other studies conducted in several different places. Ant species richness decreased with altitude; most species occur below 800 m a.s.l. (171), and only a few species occur above1600 m a.s.l. (17). Some genera occur only at a specific altitude (e.g., Azteca and Dolichoderus at 800/900 m a.s.l.; Leptogenys and Labidus at 1400 m a.s.l.), which points out to the potential use of ants as biological indicators. Our results suggest that the rocky grasslands favor high ant diversity. The patterns of ant richness associated with the altitude gradient reinforce the idea of considering the rocky grasslands as priority areas for biological conservation. Moreover, we observed a lack of records on the occurrence of most ant species considered in the present study (93%), which shows that Brazilian myrmecologists need to invest more in taxonomy, management, and data sharing
Ant Assemblage Structure in a Secondary Tropical Dry Forest: The Role of Ecological Succession and Seasonality
This study identified the main biological mechanisms governing the diversity of ants on different ecological time scales. Ants were sampled in 15 plots distributed in early, intermediate and late stages of succession (five plots per stage) at the Parque Estadual da Mata Seca, Brazil. At each sample point, unbaited pitfall traps were installed in hypogaeic, epigaeic and arboreal strata. We collected 95 ant species from 26 genera and nine subfamilies. Our results indicated that there was an increase in species richness in advanced stages of succession. We also observed that ant assemblages were different among successional stages. For the arboreal and epigaeic strata, species richness did not change with succession progression, but species composition of these two strata differed among successional stages. Unlike to arboreal and epigaeic ants, hypogaiec ant species richness was higher in the intermediate and late stages of succession and the composition of hypogaeic ants differed among successional stages. Similarity between ant species foraging in arboreal and epigaeic strata decreases with succession progression and β-diversity was higher in advanced successional stages. Additionally, species richness was higher in the dry season, whereas the composition of ant assemblages did not change between seasons. A considerable fraction of the ant assemblage was found only in advanced stages of succession, demonstrating the importance of secondary habitats in maintaining biodiversity in dry forests
Galhas de insetos em habitats xérico e mésico em região de transição Cerrado-Caatinga no norte de Minas Gerais, Brasil
Galls are morphological changes caused by endoparasites on plants, mainly related to insects. Several hypotheses have been proposed to explain the patterns of gall richness. In this study, we tested the harsh environment hypothesis, which suggests higher galling richness in xeric habitats when compared to mesic habitats. In addition, we describe the richness of gall induced-insects on their host plants in a transition Cerrado-Caatinga, Brazil. Sampling was performed along of five trajectory of an “imaginary line,” traveled at a natural walking pace over the course of one hour in each of the three adjacent habitats (cerrado, dry forest and riparian forest). We found 98 different morphospecies of galling insects on 70 plant species belonging to 20 families. Gall richness was higher in the xeric habitats (cerrado and dry forest) when compared to mesic habitat (riparian forest). Gall richness differed significantly among the gall-inducing taxa; most galls morphospecies were induced by the Diptera (Cecidomyiidae). In general, richness of all gall-inducing taxa was higher in the xeric habitats than in the mesic habitat. The highest gall richness was found on leaves of the host plants of the riparian forest and cerrado, while the stem represented the organ most attacked in the dry forest. Although there is lower availability of sites for oviposition by female galling in the dry forest during the dry season, we found higher gall richness in this environment when compared to riparian forest. In this way, confirming the harsh environment hypothesis despite the absence of leaves. Likely, there was high gall irradiation on organ exposed continuously to gall attack during ecological time in dry forest. However, further studies are needed to clarify the forces related to differential gall performance among habitats, particularly in threatened Cerrado-Caatinga transition.Key words: Cerrado, seasonally dry tropical forests, harsh environment hypothesis, galling insects, host plants.Galhas sĂŁo modificações morfolĂłgicas provocadas por endoparasitas, principalmente insetos, em tecidos vegetais. Várias hipĂłteses tĂŞm sido propostas para explicar os padrões observados para a riqueza de galhas. Nesse cenário, testou-se a hipĂłtese do estresse ambiental, que prediz que a riqueza de galhas Ă© maior em habitats xĂ©ricos quando comparados a habitats mĂ©sicos, alĂ©m de descrever a riqueza de galhas induzidas por insetos sobre suas plantas hospedeiras em habitats de transição Cerrado-Caatinga. A amostragem de galhas e plantas hospedeiras foi realizada por meio de caminhadas ao longo de cinco transectos, com duração de uma hora cada, em cada um dos trĂŞs habitats adjacentes (cerrado, mata ciliar e mata seca). Foram observadas 98 morfoespĂ©cies de galhas sobre 70 espĂ©cies de plantas (20 famĂlias). A riqueza de galhas foi maior em habitats xĂ©ricos (cerrado e mata seca) quando comparados ao habitat mĂ©sico (mata ciliar). Foi verificada uma variação significativa quanto Ă riqueza de galhas em função do táxon indutor, ocorrendo uma maior riqueza de galhas formadas por insetos da ordem Diptera (famĂlia Cecidomyiidae). No geral, todos os táxons indutores de galhas apresentaram maior riqueza em habitats xĂ©ricos do que no habitat mĂ©sico. A folha foi o ĂłrgĂŁo vegetal mais atacado na mata ciliar e no cerrado, enquanto o caule foi o ĂłrgĂŁo mais atacado na mata seca. Apesar de existir menor disponibilidade de sĂtios para oviposição por galhadores na mata seca durante o perĂodo seco, foi encontrada maior riqueza de galhas nesse ambiente, quando comparado Ă mata ciliar, corroborando, portanto, a hipĂłtese do estresse ambiental. Possivelmente, na mata seca existiu forte pressĂŁo evolutiva de galhadores sobre ĂłrgĂŁos continuamente expostos durante o tempo ecolĂłgico. Entretanto, ressalta-se a necessidade de estudos mais amplos sobre os mecanismos responsáveis pela performance diferencial de galhadores em regiões de transição, particularmente entre o Cerrado e a Caatinga.Palavras-chave: Cerrado, floresta tropical seca, hipĂłtese do estresse ambiental, insetos galhadores, plantas hospedeiras
Fluctuating asymmetry of and herbivory on Poincianella pyramidalis (Tul.) L.P. Queiroz (Fabaceae) in pasture and secondary tropical dry forest
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest
Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
Structure habitat effects of canopy insects herbivorous
O dossel de florestas tropicais oferece uma grande diversidade de recursos que sĂŁo essenciais para a manutenção da biodiversidade. Entretanto, poucos estudos verificaram os efeitos da estrutura do dossel sobre comunidades de insetos herbĂvoros em regiões tropicais. O objetivo deste estudo foi responder por que a diversidade de insetos herbĂvoros varia no dossel de uma floresta. Para isso foi testada a hipĂłtese de que a abundancia e riqueza de insetos herbĂvoros sĂŁo afetadas pela estrutura do dossel em duas escalas espaciais distintas, verificando estes efeitos em duas guildas alimentares: insetos herbĂvoros sugadores e mastigadores. Foram amostrados 314 insetos herbĂvoros. A guilda de insetos herbĂvoros mastigadores foi mais rica e abundante, apresentando 91 morfoespecies e 235 indivĂduos. Foi verificado que a estrutura do dossel influencia a abundancia e riqueza de insetos herbĂvoros em diferentes escalas espaciais, de acordo com a guilda alimentar. Insetos herbĂvoros sugadores respondem aos efeitos da arquitetura da árvore hospedeira na escala local (arquitetura da árvore), aumentando a abundancia e riqueza de espĂ©cies com o aumento do tamanho da árvore hospedeira. Já insetos herbĂvoros mastigadores aumentam sua abundancia com o tamanho da árvore hospederia, na escala local, e aumentam a sua abundancia e a riqueza de espĂ©cies com a densidade foliar do dossel, na escala regiões do dossel. Ambas as guildas nĂŁo sĂŁo afetadas pela complexidade das copas das árvores ou pela riqueza de espĂ©cies de árvores.The canopy of tropical forests offers a large diversity of resources that are essential for the maintenance of the biodiversity. There is a lack of studies on the effects of canopy habitat structure upon herbivorous communities, mainly at tropical regions. The aim of this study was to answer why herbivorous insect diversity varies within the forest canopy. We tested the hypothesis that herbivores abundance and species richness are affected by canopy structure, comparing two distinct spatial scales and two different feeding guilds: sap-sucking and chewing herbivores. We collected 314 herbivorous insect individuals. Herbivorous chewers was the richest and most abundant guild, with 91 morphospecies and 235 individuals. Canopy structure influences insect herbivore s abundance and species richness in different spatial scales, according to the herbivore s guild. Sap-sucking herbivores respond to plant architecture on a local spatial scale (tree architecture), increase their abundance and species richness with tree size. While chewing herbivores increase their abundance with tree size, and increase their abundance and species richness with leaf density within the canopy, on a larger spatial scale. Neither of the herbivorous guilds species richness were affected by tree crown complexity nor tree species richness.Conselho Nacional de Desenvolvimento CientĂfico e TecnolĂłgic