RESUMO
Climate change could pose an urgent threat to pollinators, with critical ecological and economic consequences. However, for most insect pollinator species, we lack the long-term data and mechanistic evidence that are necessary to identify climate-driven declines and predict future trends. Here we document 16 years of abundance patterns for a hyper-diverse bee assemblage1 in a warming and drying region2, link bee declines with experimentally determined heat and desiccation tolerances, and use climate sensitivity models to project bee communities into the future. Aridity strongly predicted bee abundance for 71% of 665 bee populations (species × ecosystem combinations). Bee taxa that best tolerated heat and desiccation increased the most over time. Models forecasted declines for 46% of species and predicted more homogeneous communities dominated by drought-tolerant taxa, even while total bee abundance may remain unchanged. Such community reordering could reduce pollination services, because diverse bee assemblages typically maximize pollination for plant communities3. Larger-bodied bees also dominated under intermediate to high aridity, identifying body size as a valuable trait for understanding how climate-driven shifts in bee communities influence pollination4. We provide evidence that climate change directly threatens bee diversity, indicating that bee conservation efforts should account for the stress of aridity on bee physiology.
Assuntos
Abelhas , Mudança Climática , Dessecação , Ecossistema , Temperatura Alta , Animais , Abelhas/anatomia & histologia , Abelhas/classificação , Abelhas/fisiologia , Biodiversidade , Tamanho Corporal/fisiologia , Aquecimento Global , Modelos Biológicos , Plantas , Polinização/fisiologia , Masculino , FemininoRESUMO
Elucidating the evolutionary processes that drive population divergence can enhance our understanding of the early stages of speciation and inform conservation management decisions. The honeybee Apis cerana displays extensive population divergence, providing an informative natural system for exploring these processes. The mainland lineage A. cerana includes several peripheral subspecies with disparate ecological and geographical settings radiated from a central ancestor. Under this evolutionary framework, we can explore the patterns of genome differentiation and the evolutionary models that explain them. We can also elucidate the contribution of non-genomic spatiotemporal mechanisms (extrinsic features) and genomic mechanisms (intrinsic features) that influence these genomic differentiation landscapes. Based on 293 whole genomes, a small part of the genome is highly differentiated between central-peripheral subspecies pairs, while low and partial parallelism partly reflects idiosyncratic responses to environmental differences. Combined elements of recurrent selection and speciation-with-gene-flow models generate the heterogeneous genome landscapes. These elements weight differently between central-island and other central-peripheral subspecies pairs, influenced by glacial cycles superimposed on different geomorphologies. Although local recombination rates exert a significant influence on patterns of genomic differentiation, it is unlikely that low-recombination rates regions were generated by structural variation. In conclusion, complex factors including geographical isolation, divergent ecological selection and non-uniform genome features have acted concertedly in the evolution of reproductive barriers that could reduce gene flow in part of the genome and facilitate the persistence of distinct populations within mainland lineage of A. cerana.
Assuntos
Fluxo Gênico , Genética Populacional , Abelhas/genética , Abelhas/classificação , Animais , Especiação Genética , Geografia , Seleção Genética , Variação Genética , GenômicaRESUMO
Small carpenter bees in the genus Ceratina are behaviourally diverse, species-rich, and cosmopolitan, with over 370 species and a range including all continents except Antarctica. Here, we present the first comprehensive phylogeny of the genus based on ultraconserved element (UCE) phylogenomic data, covering a total of 185 ingroup specimens representing 22 of the 25 current subgenera. Our results support most recognized subgenera as natural groups, but we also highlight several groups in need of taxonomic revision - particularly the nominate subgenus Ceratina sensu stricto - and several clades that likely need to be described as new subgenera. In addition to phylogeny, we explore the evolutionary history of Ceratina through divergence time estimation and biogeographic reconstruction. Our findings suggest that Ceratinini split from its sister tribe Allodapini about 72 million years ago. The common ancestor of Ceratina emerged in the Afrotropical realm approximately 42 million years ago, near the Middle Eocene Climatic Optimum. Multiple subsequent dispersal events led to the present cosmopolitan distribution of Ceratina, with the majority of transitions occurring between the Afrotropics, Indomalaya, and the Palearctic. Additional movements also led to the arrival of Ceratina in Madagascar, Australasia, and a single colonization of the Americas. Dispersal events were asymmetrical overall, with temperate regions primarily acting as destinations for migrations from tropical source regions.
Assuntos
Filogenia , Filogeografia , Animais , Abelhas/genética , Abelhas/classificação , Teorema de Bayes , Análise de Sequência de DNARESUMO
Assigning a query individual animal or plant to its derived population is a prime task in diverse applications related to organismal genealogy. Such endeavors have conventionally relied on short DNA sequences under a phylogenetic framework. These methods naturally show constraints when the inferred population sources are ambiguously phylogenetically structured, a scenario demanding substantially more informative genetic signals. Recent advances in cost-effective production of whole-genome sequences and artificial intelligence have created an unprecedented opportunity to trace the population origin for essentially any given individual, as long as the genome reference data are comprehensive and standardized. Here, we developed a convolutional neural network method to identify population origins using genomic SNPs. Three empirical datasets (an Asian honeybee, a red fire ant, and a chicken datasets) and two simulated populations are used for the proof of concepts. The performance tests indicate that our method can accurately identify the genealogy origin of query individuals, with success rates ranging from 93 % to 100 %. We further showed that the accuracy of the model can be significantly increased by refining the informative sites through FST filtering. Our method is robust to configurations related to batch sizes and epochs, whereas model learning benefits from the setting of a proper preset learning rate. Moreover, we explained the importance score of key sites for algorithm interpretability and credibility, which has been largely ignored. We anticipate that by coupling genomics and deep learning, our method will see broad potential in conservation and management applications that involve natural resources, invasive pests and weeds, and illegal trades of wildlife products.
Assuntos
Aprendizado Profundo , Animais , Abelhas/genética , Abelhas/classificação , Formigas/genética , Formigas/classificação , Genética Populacional , Galinhas/genética , Galinhas/classificação , Polimorfismo de Nucleotídeo Único , Genômica , FilogeniaRESUMO
Recent declines in insect abundances, especially populations of wild pollinators, pose a threat to many natural and agricultural ecosystems. Traditional species monitoring relies on morphological character identification and is inadequate for efficient and standardized surveys. DNA barcoding has become a standard approach for molecular identification of organisms, aiming to overcome the shortcomings of traditional biodiversity monitoring. However, its efficacy depends on the completeness of reference databases. Large DNA barcoding efforts are (almost entirely) lacking in many European countries and such patchy data limit Europe-wide analyses of precisely how to apply DNA barcoding in wild bee identification. Here, we advance towards an effective molecular identification of European wild bees. We conducted a high-effort survey of wild bees at the junction of central and southern Europe and DNA barcoded all collected morphospecies. For global analyses, we complemented our DNA barcode dataset with all relevant European species and conducted global analyses of species delimitation, general and genus-specific barcoding gaps and examined the error rate in DNA data repositories. We found that (i) a sixth of all specimens from Slovenia could not be reliably identified, (ii) species delimitation methods show numerous systematic discrepancies, (iii) there is no general barcoding gap across all bees and (iv) the barcoding gap is genus specific, but only after curating for errors in DNA data repositories. Intense sampling and barcoding efforts in underrepresented regions and strict curation of DNA barcode repositories are needed to enhance the use of DNA barcoding for the identification of wild bees.
Assuntos
Código de Barras de DNA Taxonômico , Animais , Código de Barras de DNA Taxonômico/métodos , Abelhas/genética , Abelhas/classificação , Europa (Continente) , BiodiversidadeRESUMO
Solitary bees and wasps that nest in cavities in tree trunks are important components of terrestrial ecosystems, providing pollination services, and in the case of wasps, the regulation of their prey populations. However, little is known about the vertical strata where bees and wasps build their nests. This is especially the case of urban forest remnants in the Amazon, which is relevant in the context of the global crisis in insect losses. We investigated the existence of vertical stratification in the nesting of solitary bees and wasps in an urban forest in Rio Branco, state of Acre, in the western Brazilian Amazon. We focused on whether wood temperature, ants, and termites are predictors of bee and wasp nesting. We sampled bee and wasp nests in the forest using trap-nests made with wooden blocks containing cavities with three different diameters for twelve months. Trap-nests were installed randomly at three heights in the forest. We collected 145 nests of 25 species, belonging to 11 genera and 6 families. A higher number of nests and species were collected in the upper stratum of the forest, strengthening the hypothesis that there is vertical stratification in the assemblage of solitary bees and wasps. Wood surface temperature and termite attacks on trap-nests were significantly different between strata, which may explain the vertical stratification of bee and wasp assemblages. Considering the importance of these insects for tropical forest ecosystems, the conservation of structurally complex and stratified forests is of paramount importance to maintain the diversity of this insect group.
Assuntos
Florestas , Vespas , Animais , Brasil , Abelhas/classificação , Vespas/fisiologia , Vespas/classificação , Comportamento de Nidação , TemperaturaRESUMO
One of the most challenging aspects of bee ecology and conservation is species-level identification, which is costly, time consuming, and requires taxonomic expertise. Recent advances in the application of deep learning and computer vision have shown promise for identifying large bumble bee (Bombus) species. However, most bees, such as sweat bees in the genus Lasioglossum, are much smaller and can be difficult, even for trained taxonomists, to identify. For this reason, the great majority of bees are poorly represented in the crowdsourced image datasets often used to train computer vision models. But even larger bees, such as bumble bees from the B. vagans complex, can be difficult to separate morphologically. Using images of specimens from our research collections, we assessed how deep learning classification models perform on these more challenging taxa, qualitatively comparing models trained on images of whole pinned specimens or on images of bee forewings. The pinned specimen and wing image datasets represent 20 and 18 species from 6 and 4 genera, respectively, and were used to train the EfficientNetV2L convolutional neural network. Mean test precision was 94.9% and 98.1% for pinned and wing images respectively. Results show that computer vision holds great promise for classifying smaller, more difficult to identify bees that are poorly represented in crowdsourced datasets. Images from research and museum collections will be valuable for expanding classification models to include additional species, which will be essential for large scale conservation monitoring efforts.
Assuntos
Aprendizado Profundo , Asas de Animais , Abelhas/anatomia & histologia , Abelhas/classificação , Animais , Asas de Animais/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Especificidade da EspécieRESUMO
The identification of meliponicultural flora is fundamental for the preservation of bees, as well as enabling the development of pollinator management and reforestation programs. In this context, this study aimed to investigate the types of pollen found in the honey and pollen pots of the Melipona fasciculata bee in Arari, State of Maranhão, between August 2022 and July 2023. 40 types of pollen were identified, distributed among 18 botanical families, with Fabaceae standing out (46.15% in pollen pots and 37.86% in honey pots), Myrtaceae (11.53% in pollen and 13.51% in honey) and Rubiaceae (7.69% in pollen and 5.40% in honey). Sapindaceae, in the honey pots, accounted for 5.40%. The other families showed lower percentages, 3.84% in the pollen pots and 2.70% in the honey pots. In terms of similarity, two distinct groups were observed in both the pollen and honey pots. In the pollen pots, group A (May-June ~ 97%) and group B (Feb-Mar ~ 99%) stood out, while in the honey pots, group A (Mar-Apr ~ 98%) and group B (Jun-Jul-Sept ~ 98%) showed the highest percentages. These findings highlight the wide range of resources used by the M. fasciculata species, as well asits preference for Fabaceae and Myrtaceae, due to the diversity and availability of trophic resources. An understanding of the meliponicultural flora is essential to support effective conservation strategies, which aim not only to guarantee the survival of the bees, but also to ensure the continued production of honey, a resource of great importance to local communities.
Assuntos
Mel , Pólen , Pólen/classificação , Mel/análise , Abelhas/classificação , Abelhas/fisiologia , Animais , Brasil , Estações do Ano , PolinizaçãoRESUMO
BACKGROUND: Understanding connections between biodiversity and ecosystem services can be enhanced by shifting focus from species richness to functional trait-based approaches, that when paired with comparative phylogenetic methods can provide even deeper insights. We investigated the functional ecology and phylogenetic diversity of pollination services provided by hymenopteran insects visiting apple flowers in orchards surrounded by either 'natural' or 'disturbed' landscapes in New South Wales, Australia. We assessed whether morphological and behavioural traits (hairiness, body size, glossa length, pollen load purity, and probability of loose pollen) exhibited non-random phylogenetic patterns. Then, explored whether bees, the primary pollinators in this system, filled unique or overlapping functional entities (FEs). For each landscape, we calculated phylogenetic diversity and used FEs to assess functional richness, evenness, and diversion. RESULTS: A phylogenomic matrix based on ultraconserved elements (UCEs; 1,382,620 bp from 1,969 loci) was used to infer a fully-resolved and well-supported maximum likelihood phylogeny for 48 hymenopteran morphospecies. There was no significant difference in species richness between landscape categories. Pollinator communities at natural sites had higher phylogenetic complexity (X = 2.37) and functional divergence (xÌ = 0.74 ± 0.02 s.e.) than disturbed sites (X = 1.65 and xÌ = 0.6 ± 0.01 s.e.). Hairiness showed significant phylogenetic clustering (K = 0.94), whereas body size, glossa length, and loose pollen showed weaker non-random phylogenetic patterns (K between 0.3-0.5). Pollen load purity showed no association with phylogeny. The assemblage of 17 bee morphospecies comprised nine FEs: eight FEs consisted of native bees with three containing 65% of all native bee taxa. The introduced honey bee (Apis mellifera) occupied a unique FE, likely due to its different evolutionary history. Both landscape types supported six FEs each with three overlapping: two native bee FEs and the honey bee FE. CONCLUSIONS: Bee hairiness was the only functional trait to exhibit demonstrable phylogenetic signal. Despite differences in species richness, and functional and phylogenetic diversity between orchard landscape types, both maintained equal bee FE numbers. While no native bee taxon was analogous to the honey bee FE, four native bee FEs shared the same hairiness level as honey bees. Health threats to honey bee populations in Australia will likely disrupt pollination services to apple, and other pollination-dependent food crops, given the low level of functional redundancy within the investigated pollinator assemblages.
Assuntos
Filogenia , Polinização , Animais , Abelhas/fisiologia , Abelhas/classificação , Malus/genética , Produtos Agrícolas/genética , Biodiversidade , New South Wales , FrutasRESUMO
Resumen Introducción: El conocimiento de la riqueza vegetal y la estacionalidad alrededor de los apiarios de Apis mellifera es una herramienta de planificación indispensable para los apicultores. Debe incluir la disponibilidad de recursos, las preferencias alimenticias y el comportamiento de búsqueda de alimento. Dicha información no está disponible para las Yungas argentinas, uno de los ecosistemas forestales más estacionales de América del Sur. Objetivo: Evaluar la disponibilidad de recursos tróficos a través de un calendario de floración y su relación con las cargas de polen de A. mellifera en las Yungas. Métodos: En El Fuerte, Jujuy, recolectamos muestras mensuales de septiembre a marzo (2014-2015 y 2015-2016) utilizando trampas de polen. Utilizamos técnicas estandarizadas para los análisis palinológicos e índices de asociación para el uso de recursos. Las fenofases fueron Inicio de floración, Plena floración y Fin de floración. Resultados: Se identificaron 47 especímenes botánicos a nivel de especie y 9 a nivel de género. En ambos períodos hubo una oferta moderada de flores al inicio de la primavera, representada igualmente por plantas arbustivas y herbáceas, con un pico de floración en noviembre. Posteriormente, hubo una caída en la disponibilidad, con un pico de floración nuevamente al final de la temporada. En cinco especies de plantas hubo una asociación de media a alta entre la especie vegetal disponible y la presencia de ésta en el espectro polínico de la muestra de polen corbicular recolectada (Vachellia aroma, Blepharocalyx salicifolius, Cantinoa sp., Vernonanthura sp. y Zanthoxylum coco). Conclusión: En esta región hay una oferta moderada de flores de plantas arbustivas y herbáceas a principios de la primavera, con un pico de floración en noviembre y al final de la temporada. Solo cinco, de casi 50 especies de plantas, muestran una asociación de disponibilidad y uso por parte de las abejas.
Abstract Introduction: Knowledge of vegetation richness and seasonality around Apis mellifera apiaries is an indispensable planning tool for beekeepers. It must include resource availability, food preferences and foraging behaviour. Such information is unavailable for the Argentinian Yungas, one of the most seasonal forest ecosystems in South America. Objective: To assess the availability of trophic resources through a flowering calendar and its relationship with A. mellifera pollen loads in the Yungas. Methods: In El Fuerte, Jujuy, we collected monthly samples from September to March (2014-2015 and 2015-2016) using pollen traps. We used standardized techniques for palynological analyses, and association indices for resource use. The phenophases were Beginning of flowering, Full flowering, and End of flowering. Results: We identified 47 botanical specimens to species level and 9 only to genus. In both periods there was a moderate supply of flowers at the beginning of spring, represented equally by shrub and herbaceous plants, with peak flowering in November. Subsequently, there was a drop in availability, with peak flowering again at the end of the season. In five plant species, there was a medium to high association between the plant species available and their presence in the pollen spectrum of the corbicular pollen samples collected (Vachellia aroma, Blepharocalyx salicifolius, Cantinoa sp., Vernonanthura sp. And Zanthoxylum coco). Conclusion: In this region, there is a moderate supply of shrub and herbaceous plant flowers at the beginning of spring, with peak flowering in November and at the end of the season. Only five, out of nearly 50 plant species, show an association of availability and use by bees.
Assuntos
Animais , Abelhas/classificação , Polinização/fisiologia , ArgentinaRESUMO
Abstract Background and aim: Stingless bee propolis, a resinous compound processed by mandibular secretion of stingless bees, is used for maintenance of hygiene and stability of beehives. Research on stingless bee propolis shows therapeutic properties attributed to polyphenols exhibiting antioxidative, antihyperglycemic and antiischemic effect. However, the cardioprotective effect of stingless bee propolis on diabetic cardiomyopathy is unknown. Methods: Adult male Sprague Dawley rats were randomised to five groups: normal group, diabetic group, diabetic given metformin (DM+M), diabetic given propolis (DM+P) and diabetic given combination therapy (DM+M+P) and treated for four weeks. Body weight, fasting blood glucose, food and water intake were taken weekly. At the end of experiment, biomarkers of oxidative damage were measured in serum and heart tissue. Antioxidants in heart tissue were quantified. Part of left ventricle of heart was processed for histological staining including Haematoxylin and Eosin (H&E) stain for myocyte size and Masson's Trichrome (MT) stain for heart fibrosis and perivascular fibrosis. Results: Propolis alleviated features of diabetic cardiomyopathy such as myocyte hypertrophy, heart fibrosis and perivascular fibrosis associated with improvement in antioxidative status. Conclusion: This study reports beneficial effect of propolis and combination with metformin in alleviating histopathological feature of diabetic cardiomyopathy by modulating antioxidants, making propolis an emerging complementary therapy.
Assuntos
Animais , Masculino , Ratos , Própole/efeitos adversos , Abelhas/classificação , Cardiomiopatias Diabéticas/patologia , Coloração e Rotulagem/instrumentação , Glicemia/metabolismo , Ratos Sprague-Dawley/classificação , Cardiomegalia/patologia , Amarelo de Eosina-(YS) , Ingestão de Líquidos , Ventrículos do Coração/anormalidades , Hipoglicemiantes , Metformina/agonistas , Antioxidantes/efeitos adversosRESUMO
Abstract The distribution of most species occurs in delimited regions with unique characteristics called "centers of endemism". In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70's. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees' responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.
Resumo A distribuição da maioria das espécies ocorre em regiões delimitadas com características únicas conhecidas como "centros de endemismo". Na Amazônia Oriental está localizado o Centro de Endemismo Belém (CEB), uma das áreas mais intensivamente desmatadas na Amazônia Brasileira. Aqui, apresentamos informações sobre assembleias de abelhas orquídeas baseadas em registros históricos de coleções entomológicas. Para cada espécie, foram calculadas a frequência de ocorrência e a dominância, classificando-as em 3 estados: espécies comuns, intermediárias ou raras. Foram geradas curvas de riqueza observada e estimada, com base no estimador Jackknife. Encontramos 1.257 espécimes de 56 espécies, constituindo registros de 1917 a 2009, e uma espécie é um novo registro no CEB. Maior número de espécimes e espécies foi concentrado em poucos locais, com intensificação nas coletas a partir dos anos70. Os resultados sugerem alta riqueza de abelhas orquídeas no CEB, embora esse cenário esteja longe do que é esperado para toda a área. A elevada ocorrência de espécies raras pode estar relacionada à baixa representatividade nas coleções e a proximidade entre as áreas favoreceu as amostragens. Mesmo assim, a lista de espécies e o estado de conservação aqui apresentados podem ser informações úteis em estudos interessados em comparar a fauna passada e atual de abelhas das orquídeas e, aliado a dados sobre as respostas das abelhas às mudanças de uso da terra ocorridas no CEB ao longo dos anos, podem servir de base para definição de áreas prioritárias para conservação.
Assuntos
Animais , História do Século XX , História do Século XXI , Abelhas/classificação , Abelhas/fisiologia , Brasil , Espécies em Perigo de Extinção , Conservação dos Recursos NaturaisRESUMO
In this study, we investigated the chemical composition, and antioxidant and antibacterial properties of ethanolic extracts of propolis (EEP) from Melipona quadrifasciata quadrifasciata and Tetragonisca angustula. Chemical composition of EEP was determined by colorimetry and chromatographic (HPLC-DAD and UPLC-Q/TOF-MS/MS) analysis. Antimicrobial activity of EEP was evaluated against gram-positive (S. aureus, methicillin-resistant S. aureus, E. faecalis) and gram-negative (E. coli and K. pneumoniae) bacteria by the minimal inhibitory concentration (MIC) test using the microdilution method. Furthermore, the growth curve and integrity of cell membrane of S. aureus and E. coli were investigated using standard microbiological methods. HPLC-DAD analysis showed that the EEP of M. quadrifasciata quadrifasciata has a more complex chemical composition than the EEP of T. angustula. Moreover, UPLC-MS analyses of M. quadrifasciata quadrifascita indicated flavonoids and terpenes as major constituents. The bactericidal activity of both EEPs was higher against gram-positive bacteria than for gram-negative bacteria. The EEP from M. quadrifasciata quadrifasciata presented MIC values lower than the EEP from T. angustula for all tested bacteria. The EEP from M. quadrifasciata quadrifasciata caused lysis of the bacterial wall and release of intracellular components from both E. coli and S. aureus. Our findings indicate that the chemical composition of propolis from stingless bees is complex and depends on the species. The extract from M. quadrifasciata quadrifascita was more effective against gram-positive than gram-negative strains, especially against S. aureus and methicillin-resistant S. aureus compared to T. angustula extract, by a mechanism that involves disturbance of the bacterial cell membrane integrity.
Assuntos
Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Abelhas/classificação , Bactérias Gram-Negativas/efeitos dos fármacos , Própole/química , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Colorimetria , Bactérias Gram-Negativas/classificação , Bactérias Gram-Positivas/classificação , Testes de Sensibilidade Microbiana , Espectrometria de Massas em TandemRESUMO
ABSTRACT Samburá is the botanical pollen nectar agglutinated by salivary secretions of bees. Stingless bee pollen samples were collected in three periods of the year in Monsenhor Gil town, PI, Brazil, for extraction of volatile constituents by different techniques, analyzed by gas chromatography-mass spectrometry (GC-MS) and the palynological analysis used to identify the dominant pollen. Among the volatile compounds identified, kaur-16-ene, methyl and ethyl hexadecanoate, methyl linoleate and heneicosane were identified more frequently in the studied parameters: period of sample collection and extraction techniques used. The palynological analysis identified the pollen of Mimosa caesalpiniifolia Benth. as the dominant pollen in all samples studied.
Assuntos
Abelhas/classificação , Compostos Orgânicos Voláteis/farmacologia , Pólen/metabolismo , Mimosa/classificação , Cromatografia Gasosa-Espectrometria de Massas/instrumentaçãoRESUMO
Abstract Pollinators provide an essential service to natural ecosystems and agriculture. In tomatoes flowers, anthers are poricidal, pollen may drop from their pore when flowers are shaken by the wind. However, bees that vibrate these anthers increase pollen load on the stigma and in fruit production. The present study aimed to identify the pollinator richness of tomato flowers and investigate their morphological and functional traits related to the plant-pollinator interaction in plantations of Central Brazil. The time of anthesis, flower duration, and the number and viability of pollen grains and ovules were recorded. Floral visitors were observed and collected. Flower buds opened around 6h30 and closed around 18h00. They reopened on the following day at the same time in the morning, lasting on average 48 hours. The highest pollen availability occurred during the first hours of anthesis. Afterwards, the number of pollen grains declined, especially between 10h00 to 12h00, which is consistent with the pollinator visitation pattern. Forty bee species were found in the tomato fields, 30 of which were considered pollinators. We found that during the flowering period, plants offered an enormous amount of pollen to their visitors. These may explain the high richness and amount of bees that visit the tomato flowers in the study areas. The period of pollen availability and depletion throughout the day overlapped with the bees foraging period, suggesting that bees are highly effective in removing pollen grains from anthers. Many of these grains probably land on the stigma of the same flower, leading to self-pollination and subsequent fruit development. Native bees (Exomalopsis spp.) are effective pollinators of tomato flowers and are likely to contribute to increasing crop productivity. On the other hand, here tomato flowers offer large amounts of pollen resource to a high richness and amount of bees, showing a strong plant-pollinator interaction in the study agroecosystem.
Resumo Polinizadores fornecer um serviço essencial para os ecossistemas naturais e para agricultura. Em tomateiros, as anteras são poricidas e o pólen pode sair a partir dos poros quando as flores são agitadas pelo vento. No entanto, as abelhas que vibram as anteras aumentam a carga de pólen no estigma e na produção de frutos. O presente estudo teve como objetivo identificar a riqueza dos polinizadores das flores de tomate e investigar suas características morfológicas e funcionais relacionadas com a interação planta-polinizador em plantações do Brasil central. Foram registrados o tempo de antese, duração flor, bem como o número e viabilidade de grãos de pólen e óvulos. Os visitantes florais foram observados e coletados. Os botões florais abriram-se em torno 06h30 e fechou em torno de 18h00. As flores reabrem no dia seguinte ao mesmo tempo na parte da manhã, com longevidade média de 48 horas. A maior disponibilidade de pólen ocorreu durante as primeiras horas da antese. Depois disso, o número de grãos de pólen diminuiu, especialmente entre as 10h00 às 12h00, o que é consistente com os padrões de visitação de polinizadores. Quarenta espécies de abelhas foram encontradas nos campos de tomate, 30 das quais foram consideradas polinizadores. Durante o período de floração, as plantas oferecem enorme quantidade de pólen para os seus visitantes. Isto pode explicar a alta riqueza e quantidade de abelhas que visitam as flores de tomate nas áreas de estudo. O período de disponibilidade e redução de pólen durante todo o período do dia é sobreposto com o período de alimentação das abelhas, o que sugere que elas são altamente eficazes na remoção de grãos de pólen das anteras. Muitos desses grãos provavelmente são depositados no estigma da mesma flor, levando à auto-polinização e o desenvolvimento de frutos. Abelhas nativas (Exomalopsis spp.) são polinizadores efetivos de flores de tomate, podendo contribuir para o aumento da produtividade das culturas. Por outro lado, as flores de tomate oferecem grandes quantidades de pólen de recursos para uma alta riqueza e quantidade de abelhas, que mostram um estudo forte interação planta-polinizador nos agroecossistemas.
Assuntos
Animais , Abelhas/fisiologia , Solanum lycopersicum/anatomia & histologia , Solanum lycopersicum/fisiologia , Biodiversidade , Polinização , Abelhas/classificação , Brasil , Flores/anatomia & histologia , Flores/fisiologiaRESUMO
Orchid bees are important keystone pollinators from the Neotropics. With the aim to study the relationships between orchid bees and their nectar and aromatic host species, we made systematic samplings of males across two conservation areas in the biogeographic Chocó Region of Colombia. We used chemical baits to collect 352 male bees during five months. The pollen attached to their bodies was extracted for palynological identification and to estimate interaction networks. The euglossine community consisted of at least 22 species including Eg. maculilabris, Eg. orellana, Eg. championiand Eg. ignita.The male bees were associated with 84 plants but depended on a small group of them (Peperomiaspp. and Anthuriumspp, as well as species of Solanaceae, Ericaceae and Malpighiaceae) which were widely distributed across the altitudinal gradient, and were available through the year. The resulting interaction networks revealed a typical nested pattern usually found in plant-pollinator interactions, with several rare bee and plant species interaction with a small group of generalist bees and plant species. Albeit, we found variation within networks related to species composition. Such variation may be a consequence of specific differences in plant flowering phenology.
Las abejas de las orquídeas son uno de los principales grupos de polinizadores con distribución exclusivamente Neotropical. Con el fin de documentar las relaciones de estas abejas con sus plantas fuente de néctar y sustancias aromáticas, realizamos muestreos sistemáticos de 352 machos durante cinco meses usando cebos químicos para atraerlos en dos áreas de conservación en el Chocó biogeográfico. Se extrajo el polen adherido al cuerpo de los especímenes recolectados para identificación palinológica de las especies vegetales visitadas por la comunidad y posterior análisis de redes de interacciones. Encontramos que la comunidad de euglossinos está conformada por al menos 22 especies de abejas. Dentro de la comunidad fueron más comunes: Eg. maculilabris, Eg. orellana, Eg. championiy Eg. ignita.Las especies de abejas se relacionan con no menos de 84 especies de plantas pero dependen más frecuentemente de un pequeño grupo de especies vegetales ampliamente distribuidas en el gradiente altitudinal mues-treado y que se encuentran disponibles durante gran parte del año. Dentro de este pequeño grupo destacan especies pertenecientes a los géneros Anthuriumy Peperomiay a las familias Solanaceae, Ericaceae y Malpighiaceae. Las redes de interacciones resultantes muestran un patrón anidado en el que muchas especies de abejas o plantas raras interac-túan con un pequeño grupo de especies de abejas o plantas generalistas. También encontramos variaciones espaciales y temporales en las redes en cuanto a la composición de especies y la manera como se distribuyen las interacciones. Estas variaciones estarían determinadas por las diferencias en la fenología de las plantas y en las condiciones climáticas entre los sitios muestreados que se encuentran muy cercanos entre sí.
Assuntos
Animais , Masculino , Abelhas/fisiologia , Ecossistema , Orchidaceae/classificação , Polinização , Abelhas/classificação , Colômbia , Densidade Demográfica , Floresta ÚmidaRESUMO
The successful distribution of A. melliferais due to their ability to adjust to seasonal variations, considerable control over their internal physical environment and exploration of different resources. However, their populations have experienced different forms and levels of environmental pressure. This research aimed to verify the phenotypic plasticity in both size and shape of wings in A. melliferausing fluctuating asymmetry, based on geometric morphometrics from apiaries located in sites with high and low levels of anthropization. We sampled 16 locations throughout all five geographic regions of Brazil. At each site, samples were collected from 20 beehives installed in apiaries: 10 installed near high anthropogenic environments (Cassilàndia - MS, Fortaleza - CE, Maringá - PR, Aquidauana - MS, Rolim de Moura - RO, Riachuelo - SE, Ubirata - PR and Piracicaba - SP), and 10 in sites with low levels of human disturbance (Cassilàndia - MS, Itapiúna CE, Uniao da Vitoria - PR, Aquidauana - MS, Rolim de Moura - RO, Pacatuba - SE, Erval Seco - RS, Rio Claro - SP). A sample of 10 individuals was taken in each hive, totaling 200 per location, for a total of 1 600 individuals. We used fluctuating asymmetry (FA) in size and shape of the forewing through geometric morphometrics. The FA analysis was conducted in order to check bilateral differences. The indexes of size and shape were submitted to analysis of variance (ANOVA), where the characters evaluated were used as factors to verify the size and shape differences. The results indicated an asymmetry on the shape of the wing (P < 0.001) but no asymmetry was observed on wing size. Considering FA as an environmental response and high and low impacted areas as a fixed factor, we observed significant differences (P < 0.05). The results for the wing shape in A. melliferademonstrated that this feature undergoes more variation during ontogeny compared to the variation in size. We concluded that bee samples collected from colonies with higher levels of human disturbance had higher wing-shape asymmetry; the variation of fluctuating asymmetry in the wing shape of honeybees can be used as an indicator of the degree of environmental anthropization.
La distribución exitosa de A. melliferase debe a su capacidad para adaptarse a las variaciones estacionales, controlar considerablemente su ambiente físico interno y por la exploración de recursos. Sin embargo, sus poblaciones experimentan diferentes formas y niveles de presión ambiental. Esta investigación evaluó colmenares, ubicadas en entornos con distintos niveles de antropización. Ambientes considerados altamente antropogénicos fueron escogidos: áreas urbanas, agrícolas con aplicaciones de insecticidas, y las industrias con grandes áreas (regiones con altos índices de contaminación). Por otra parte, los entornos considerados con bajos niveles de perturbación humana fueron elegidos: áreas de preservación permanente de los bosques restantes (Mata Atlántica, Planalto, Cerrado), áreas ribereñas o reservas ecológicas. Se muestrearon 16 localidades que abarcan las cinco regiones del Brasil. Estamos utilizando la asimetría fluctuante desde el tamaño y la forma del ala anterior por técnicas de morfometría geométrica. En cada sitio, las muestras se obtuvieron de las 20 colmenas instaladas en los colmenares: 10 instalados cerca de entornos altamente antropogénicos (Cassilándia - MS, Fortaleza - CE, Maringá - PR, Aquidauana - MS, Rolim de Moura - RO, Riachuelo - SE, Ubirata - PR y Piracicaba - SP) y 10 en sitios de bajo nivel de perturbación humana (Cassilándia - MS, ItapiúnaCE, Uniao da Vitória - PR, Aquidauana - MS, Rolim de Moura - RO, Pacatuba- SE, Erval Seco - RS, Rio Claro - SP). Los índices de tamaño y forma fueron sometidos a análisis de varianza (ANOVA), donde se utilizaron los caracteres evaluados como factores, para verificar las diferencias de tamaño y forma. La asimetría de análisis fluctuante (AF) se llevó a cabo con el fin de comprobar las diferencias bilaterales. Los resultados indican la existencia de la asimetría de la forma del ala (P < 0.001), pero no se observó asimetría del tamaño del ala. Considerando AF como respuesta ambiental y áreas de alto y bajo grado de alteración humana como factor fijo, observamos diferencias significativas (P < 0.05). Los resultados, para la forma de ala de la A. mellifera,muestran que esta característica se somete a más variación durante la ontogenia en comparación con la variación en el tamaño. Llegamos a la conclusión de que las colonias de abejas recogidas en ambientes con niveles más altos de la perturbación humana tienen una mayor asimetría en forma de ala, por lo que la asimetría fluctuante en forma de alas de las abejas puede ser utilizada como un indicador del grado de antropización del medio ambiente.
Assuntos
Animais , Humanos , Abelhas/anatomia & histologia , Meio Ambiente , Asas de Animais/anatomia & histologia , Brasil , Abelhas/classificação , Abelhas/fisiologia , Genótipo , FenótipoRESUMO
The orchid-bee faunas (Hymenoptera: Apidae: Euglossina) of the three largest forest remnants in the “Centro de Endemismo Pernambuco”, northeastern Brazil, namely Estação Ecológica de Murici (ESEC Murici), RPPN Frei Caneca, and a forest preserve belonging to Usina Serra Grande, in the states of Alagoas and Pernambuco, were surveyed using seventeen different scents as baits to attract orchid-bee males. Eight sites were established in the three preserves, where samplings were carried out using two protocols: insect netting and bait trapping. We collected 3,479 orchid-bee males belonging to 29 species during 160 hours in early October, 2012. Seven species were collected in the “Centro de Endemismo Pernambuco” for the first time. Richness proved to be one of the highest of the entire Atlantic Forest domain, and diversity in some sites, especially at ESEC Murici, revealed to be one of the highest in the Neotropics. Eulaema felipei Nemésio, 2010, a species previously recorded only at ESEC Murici, was found in no other preserve in the region and its conservation status is discussed.
As faunas de abelhas-das-orquídeas (Hymenoptera: Apidae: Euglossina) dos três maiores remanescentes florestais do Centro de Endemismo Pernambuco, nordeste do Brazil, sendo elas a Estação Ecológica de Murici (ESEC Murici), a RPPN Frei Caneca e um remanescente florestal pertencente à Usina Serra Grande, foram amostradas com o uso de dezessete diferentes iscas aromáticas para atrair machos dessas abelhas. Oito sítios amostrais foram selecionados nas três áreas, onde amostragens foram realizadas sob duas metodologias: coleta ativa com rede entomológica e coleta com armadilhas. Foram coletados 3.479 machos de abelhas euglossinas durante 160 horas no início de outubro de 2012. Sete espécies foram registradas no Centro de Endemismo Pernambuco pela primeira vez. A riqueza da região se mostrou uma das mais altas de toda a Mata Atlântica, e a diversidade em alguns locais, especialmente na ESEC Murici, revelou-se uma das mais altas de toda a região Neotropical. Eulaema felipei Nemésio, 2010, uma espécie que só havia sido registrada na ESEC Murici, não foi encontrada em nenhuma outra área e seu estado de conservação é discutido.
Assuntos
Animais , Masculino , Biodiversidade , Abelhas/classificação , Orchidaceae , Brasil , Densidade Demográfica , Estações do AnoRESUMO
The orchid-bee fauna of the region of Tarapoto, northeastern Peru, was surveyed using seventeen different scents as baits to attract orchid-bee males. Six hundred and fifty-nine males belonging to 41 species were actively collected with insect nets during 120 hours in late July and early August, 2012. Euglossa dressleri Moure, 1968, Euglossa laurensi Bembé, 2008, and Euglossa maculilabris Moure, 1968, three species belonging to the Euglossa cybelia species-group, are here reported for Peru for the first time. Previous sporadic and unpublished samplings in the area recorded eleven additional species. With 53 species, the region of Tarapoto can be considered the richest single site in the Neotropics for orchid bees. Diversity, estimated with the Shannon-Wiener diversity index (H′ = 3.02), was also the highest ever recorded for orchid bees.
A fauna de abelhas euglossinas da região de Tarapoto, nordeste do Peru, foi amostrada com o uso de dezessete diferentes iscas aromáticas para atrair machos dessas abelhas. Seiscentos e cinquenta e nove machos pertencentes a 41 espécies foram coletados com rede entomológica durante 120 horas de amostragem no final de julho e início de agosto de 2012. Euglossa dressleri Moure, 1968, Euglossa laurensi Bembé, 2008, e Euglossa maculilabris Moure, 1968, três espécies pertencentes ao grupo Euglossa cybelia, foram registradas para o Peru pela primeira vez. Amostragens esporádicas prévias na área, não publicadas, registraram a ocorrência de doze espécies adicionais, não amostradas no presente estudo. Com 53 espécies registradas, a região de Tarapoto torna-se a área mais rica conhecida em abelhas euglossinas em toda a região Neotropical. A diversidade, estimada pelo índice de diversidade de Shannon-Wiener (H′ = 3,02), é também a mais alta já registrada para esse grupo de abelhas.