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Bees play a key role in pollination of crops and in diverse ecosystems. There have been multiple reports in recent years illustrating bee population declines worldwide. The search for more accurate forecast models can aid both in the understanding of the regular behavior and the adverse situations that may occur with the bees. It also may lead to better management and utilization of bees as pollinators. We address an investigation with Recurrent Neural Networks in the task of forecasting bees' level of activity taking into account previous values of level of activity and environmental data such as temperature, solar irradiance and barometric pressure. We also show how different input time windows, algorithms of attribute selection and correlation analysis can help improve the accuracy of our model.

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Although there have been studies of the temperature regimes within flowers, micrometeorology within stems seems to have been overlooked. We present ideas, hypotheses, and a diagrammatic model on the biophysical and thermodynamic processes that interact in complex ways to result in elevated temperature regimes within hollow stems of herbaceous plants. We consider the effects of the ambient air around the stems, the possible importance of insolation, and greenhouse effects as influenced by stems' orientation and optical properties, i.e., reflection, absorption, emissivity, translucence, pigmentation, and thermal conductivity. We propose that greenhouse effects contribute significantly to and are influenced by the above phenomena as well as by the gross anatomy (volume:surface ratio; wall thickness), evapotranspiration, and the thermal properties of the gas mixture in the lumen. We provide examples of those elevated temperatures that can be several degrees Celsius above the temperature of the surrounding atmosphere.

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Bee pollination is an indispensable component of global food production and plays a crucial role in sustainable agriculture. The worldwide decline of bee populations, including wild pollinators, poses a threat to this system. However, most studies to date are situated in temperate regions where Apini and Bombini are very abundant pollinators. Tropical and subtropical regions where stingless bees (Apidae: Meliponini) are generally very common, are often overlooked. These bees also face pressure due to deforestation and agricultural intensification as well as the growing use and spread of exotic pollinators as Apis mellifera and Bombus species. The loss or decline of this important bee tribe would have a large impact on their provided ecosystem services, in both wild and agricultural landscapes. The importance of pollinator diseases, which can contribute to decline, has not been investigated so far in this bee tribe. Here we report on the first large pathogen screening of Meliponini species in southern Brazil. Remarkably we observed that there was an absence of Leishmaniinae and Nosematidae, and a very low occurrence of Apicystis bombi. Our data on disease prevalence in both understudied areas and species, can greatly improve our knowledge on the distribution of pathogens among bee species.

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Alternative pollinators can ensure pollination services if the availability of the managed or most common pollinator is compromised. In this study, the behavior and pollination efficiency of Apis mellifera L. and two species of stingless bees, Plebeia emerina Friese and Tetragonisca fiebrigi Schwarz, were evaluated and compared in flowers of Brassica napus L. 'Hyola 61'. A. mellifera was an efficient pollinator when collecting nectar because it effectively touched the reproductive organs of the flower. In contrast, stingless bees were efficient pollinators only when collecting pollen. The number of pollen grains deposited on the stigma after a single visit by worker bees of the three species was greater than the number of grains resulting from pollination without the bee visits. On average, the three species deposited enough pollen grains to fertilize all of the flower ovules. A. mellifera and P. emerina had similar pollination efficiency because no significant differences were observed in the characteristics of the siliques produced. Although T. fiebrigi is also an effective pollinator, the seed mass produced by their pollination was lower. Native bees promoted similar rates of fruit set compared with A. mellifera. Thus, P. emerina has potential to be used for pollination in canola crops.

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Climate changes are predicted to affect the diapause of many insect species around the world adversely. In this context, bees are of interest due to their pollination services. In southern Brazil, the highly eusocial bee species Plebeia droryana (Friese) (Hymenoptera: Apidae: Meliponini) exhibits reproductive diapause in response to the region's rigorous winters. That diapause is characterized by a temporary interruption in brood cell construction by nurse bees and egg-laying by the queen, regardless of other internal tasks underway in the nests. In this study, we evaluated whether P. droryana enter diapause under experimental conditions. P. droryana colonies were kept in a germination chamber, and the temperature was progressively reduced from 20°C over a period of a few weeks until diapause was detected. Additionally, we also estimated the environmental conditions in the actual geographic range occupied by P. droryana and modeled it for predicted changes in climate up to the year 2080. Our findings indicate that P. droryana enter diapause between 10 and 8°C. We also found that the current minimum winter temperature (10.1°C, median) in the distributional range of P. droryana will probably rise (13.4°C, median). Thus, if our experimental data are somewhat accurate, ∼36% of the southern Brazilian P. droryana population may be active during the expected milder winter months in 2080. In this scenario, there may be a larger demand for pollen and nectar for that bee species. Greater conservation efforts will be required to preserve P. droryana populations and keep them viable in the coming decades.

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As abelhas são consideradas os principais polinizadores em ambientes naturais e agrícolas. Esse serviço ecossistêmico é essencial para a manutenção das populações selvagens de plantas e para a produção de alimento nos ambientes agrícolas e está ameaçado em várias regiões do mundo. O desmatamento é uma das causas principais porque ele afeta as populações de abelhas. A conservação das florestas é necessária para a manutenção das populações de abelhas e da polinização nas paisagens agrícolas.

Bees are considered the main pollinators in natural and agricultural environments. This ecosystem service is essential to the maintenance of wild plant populations and to food production on agricultural environments and it's threatened in many regions of the world. Deforestation is pointed out as one of the main causes because it affects bee populations. Conservation of forests is necessary for the maintenance of bee populations and pollination services on agricultural landscapes.

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Due to the loss of biodiversity that occurs nowadays, the development of tools that allow us to characterize this biodiversity is of great importance. The recent developed relative warps analysis is very useful at this point. We characterized a population of Nannotrigona testaceicornis collected in different areas of Uberlândia using the relative warps analysis of the forewings. The two subpopulations of the urban environment were closer to each other than the one collected in a natural area outside the city. This greater proximity and diversification in relation to the natural área subpopulation is possibly due to inbreeding, that is enhanced by the smaller amount of natural food sources. The geometric morphometric of forewings showed to be a very powerful and informative tool to assess biodiversity within a population.

Devido aos recentes alarmes causados pela perda de biodiversidade, o uso de ferramentas que permitam a caracterização desta biodiversidade é de grande importância. As técnicas de análises de deformações relativas têm se mostrado muito úteis neste ponto. Aqui, nós caracterizamos, por análises de deformações relativas das asas anteriores, uma população de Nannotrigona testaceicornis coletada em diferentes áreas de Uberlândia. As duas subpopulações de ambientes urbanos eram mais parecidas entre si do que quando comparadas com a subpopulação coletada em uma área de mata natural. Esta maior proximidade se deve possivelmente ao endocruzamento e à menor disponibilidade de alimento. A morfometria geométrica das asas anteriores se mostra ainda uma ferramenta muito útil e informativa para avaliação de biodiversidade.

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