Scalable Generation of Synthetic GPS Traces with Real-life Data Characteristics

Database benchmarking is most valuable if real-life data and workloads are available. However, real-life data (and workloads) are often not publicly available due to IPR constraints or privacy concerns. And even if available, they are often limited regarding scalability and variability of data characteristics. On the oth

Hit-and-run trophallaxis of small hive beetles

Some parasites of social insects are able to exploit the exchange of food between nestmates via trophallaxis, because they are chemically disguised as nestmates. However, a few parasites succeed in trophallactic solicitation although they are attacked by workers. The underlying mechanisms are not well understood. The small hive beetle (=SHB), Aethina tumida, is such a parasite of honey bee, Apis mellifera, colonies and is able to induce trophallaxis. Here, we investigate whether SHB trophallactic solicitation is innate and affected by sex and experience. We quantified characteristics of the trophallactic solicitation in SHBs from laboratory-reared individuals that were either bee-naïve or had 5 days experience. The data clearly show that SHB trophallactic solicitation is innate and further suggest that it can be influenced by both experience and sex. Inexperienced SHB males begged more often than any of the other groups had longer breaks than their experienced counterparts and a longer soliciting duration than both experienced SHB males and females, suggesting that they start rather slowly and gain more from experience. Successful experienced females and males were not significantly different from each other in relation to successful trophallactic interactions, but had a significantly shorter soliciting duration compared to all other groups, except successful inexperienced females. Trophallactic solicitation success, feeding duration and begging duration were not significantly affected by either SHB sex or experience, supporting the notion that these behaviors are important for survival in host colonies. Overall, success seems to be governed by quality rather than quantity of interactions, thereby probably limiting both SHB energy investment and chance of injury (<1%). Trophallactic solicitation by SHBs is a singular example for an alternative strategy to exploit insect societies without requiring chemical disguise. Hit-and-run trophallaxis is an attractive test system to get an insight into trophallaxis in the social insects

Conformal Transformations of the Wigner Function and Solutions of the Quantum Corrected Vlasov Equation

We study conformal properties of the quantum kinetic equations in curved spacetime. A transformation law for the covariant Wigner function under conformal transformations of a spacetime is derived by using the formalism of tangent bundles. The conformal invariance of the quantum corrected Vlasov equation is proven. This provides a basis for generating new solutions of the quantum kinetic equations in the presence of gravitational and other external fields. We use our method to find explicit quantum corrections to the class of locally isotropic distributions, to which equilibrium distributions belong. We show that the quantum corrected stress--energy tensor for such distributions has, in general, a non--equilibrium structure. Local thermal equilibrium is possible in quantum systems only if an underlying spacetime is conformally static (not stationary). Possible applications of our results are discussed.Comment: 30 page

Compounds extracted from heads of African stingless bees (Hypotrigona species) as a prospective taxonomic tool

Stingless bees are important pollinators of plants, and also producers of honey. Species within the African stingless bee genus Hypotrigona are difficult to differentiate due to morphological similarities. Chemical profiles of whole head extracts from workers of three Hypotrigona species: H. gribodoi, H. araujoi and H. ruspolii were studied by gas chromatography–mass spectrometry. A total of 50 components belonging to six chemical classes: hydrocarbons, aldehydes, alcohols, terpenoids, steroids and fatty acids were identified. Twenty-nine compounds were found in H. araujoi, 26 in H. gribodoi and 33 in H. ruspolii head extracts. Hydrocarbons, alcohols and fatty acids were the major classes, whilst steroids and terpenoids were minor. Aldehydes were found only in H. ruspolii while terpenoids were only present in extracts of H. gribodoi and H. araujoi. Eight chemical compounds were specific to H. araujoi, six to H. gribodoi and nine to H. ruspolii, showing both qualitative and quantitative differences. Workers were successfully grouped into their respective species using their chemical profiles. This study shows that head extracts can be used as a reliable taxonomic tool for identifying and differentiating Hypotrigona species.The European Union (EU) (Grant Contract No. DCI-FOOD/2013/313-659: African Reference Laboratory (with satellite stations) for the Management of Pollination Bee Diseases and Pests for Food Security); the South African National Research Foundation (NRF) Research Career Advancement Fellowship (Grant no: 91419) to AAY; NRF Incentive Funding for Rated Researchers to CWWP and AAY; UK Aid from the UK Government; Swedish International Development Cooperation Agency (Sida); the Swiss Agency for Development and Cooperation (SDC) and the Kenyan Government. The first author was supported by a German Academic Exchange Service (DAAD) In-Region Postgraduate Scholarship.https://link.springer.com/journal/492019-04-01hj2018Zoology and Entomolog

Nest architecture as a tool for species discrimination of Hypotrigona species (Hymenoptera: Apidae: Meliponini)

Hypotrigona species are difficult to identify morphologically. Here, we show that nest sites and nest architecture can be used to discriminate three Hypotrigona species found in Kenya. Hypotrigona gribodoi, H. araujoi and H. ruspolii colonies from Kakamega forest and H. gribodoi from Mwingi, were collected and placed in a meliponiary at the International Centre of Insect Physiology and Ecology (ICIPE). The following parameters were recorded: nest sites, internal nest entrances, external nest entrance colour and size, sizes (in terms of volume) of brood cells, honey and pollen pots, arrangement of brood cells and presence or absence of involucrum (cerumen covering brood). It was found that nest sites are specific to species. Hypotrigona gribodoi nests mostly in crevices inmudwalls whileH. ruspolii and H. araujoi nest in cavities in specific tree species, mainly in indigenous forests. The colour of external nest entrances varies between the species. H. araujoi’s is yellowish brown, H. gribodoi’s is white or cream while that ofH. ruspolii is dark brown. There is an internal nest entrance inH. gribodoi, which is absent in the other two Hypotrigona species. Brood cells are clustered in H. gribodoi and H. ruspolii whereas H. araujo’s formvertical semi comb-like layers. The area of the apical opening of the entrance tube and volumes of brood cells, honey and pollen pots differ significantly between the three Hypotrigona species. Therefore, nest sites and nest architecture can be used to discriminate three Hypotrigona species. Furthermore, the study indicates that conservation of indigenous forests, the main habitat for H. araujoi and H. ruspolii is important for their conservation.https://journals.co.za/content/journal/entohj2020Zoology and Entomolog

Floral turnover and climate drive seasonal bee diversity along a tropical elevation gradient

The contribution of seasonality in species communities to elevational diversity of tropical insects remains poorly understood. We here assessed seasonal patterns and drivers of bee diversity in the Eastern Afromontane Biodiversity Hotspot, Kenya, to understand the contribution of seasonality to elevational biodiversity patterns. Bee species and plant species visited by bees were recorded on 50 study plots in regrowth vegetation across four major seasons along two elevation gradients from 525 to 2530 m above sea level. Bees were sampled by transect walks using sweep nets and aspirators. We examined how local species richness (α-diversity) and seasonal changes in local species communities (β-diversity) contribute to species richness across seasons (γ-diversity) along elevation gradients. Using a multimodel inference framework, we identified the contribution of climate and floral seasonality to elevational patterns in bee diversity. We found that both α- and γ-diversity decreased with elevation. Seasonal β-diversity decreased with elevation and the high turnover of species across seasons contributed to a considerably higher γ- than α-diversity on study plots. A combination of seasonality in climate and the seasonal turnover of floral resources best explained the seasonality in bee species communities (seasonal β-diversity). We, therefore, conclude that, despite the more stable, and favorable climatic conditions in the tropics (in comparison to temperate regions), climatic seasonality and its influence on bees’ floral resources largely determined seasonal patterns of bee species diversity along elevation gradients on tropical mountains.JRS Biodiversity Foundation (grant number: 60610), UK’s Foreign, Commonwealth & Development Office (FCDO), the Swedish International Development Cooperation Agency (Sida), the Swiss Agency for Development and Cooperation (SDC), the Federal Democratic Republic of Ethiopia, and the Government of the Republic of Kenya.https://onlinelibrary.wiley.com/r/ecs2am2023Zoology and Entomolog

Real-Time Wildfire Monitoring Using Scientific Database and Linked Data Technologies

We present a real-time wildfire monitoring service that exploits satellite images and linked geospatial data to detect hotspots and monitor the evolution of fire fronts. The service makes heavy use of scientific database technologies (array databases, SciQL, data vaults) and linked data technologies (ontologies, linked geospatial data, stSPARQL) and is implemented on top of MonetDB and Strabon. The service is now operational at the National Observatory of Athens and has been used during the previous summer by emergency managers monitoring wildfires in Greece

The conservation of native honey bees is crucial

Recent studies have emphasized the role of the western honey bee, Apis mellifera, as a managed agricultural species worldwide, but also as a potential threat to endangered wild pollinators. This has resulted in the suggestion that honey bees should be regulated in natural areas to conserve wild pollinators. We argue that this perspective fails to appreciate the multifaceted nature of honey bees as native or introduced species with either managed or wild colonies. Wild populations of A. mellifera are currently imperiled, and natural areas are critical for the conservation of local subspecies and genotypes. We propose that a differentiation between managed and wild populations is required and encourage integrated conservation planning for all endangered wild bees, including A. mellifera.http://www.cell.com/trends/ecology-evolution/home2020-09-01hj2020Zoology and Entomolog