An assessment of optimal foraging in honeybees through decoding of waggle dances in an urban landscape

A global decline of honeybees (Apis mellifera) and other pollinators which are essential for pollinating crops and wild flowers has been reported throughout the last decades. One major cause is the loss of available resources due to agricultural intensification. Especially urban areas seem to become an important habitat for pollinators. In 2017, Stange et al. developed a habitat suitability model for pollinators indicating habitat quality in terms of available floral resources and nesting sites for the City of Oslo, Norway. Our aim was to analyse whether the foraging patterns of honeybees match with highly suitable habitat patches as indicated by the ESTIMAP model. According to the optimal foraging theory honeybees should visit the closest and most rewarding habitat patches from the hive location, maximizing energetic intake per unit time. Hence, we hypothesised that patches which were frequently visited by the studied honeybees also had a high habitat suitability value and vice versa. We studied honeybee foraging patterns over the summer 2017 by decoding 506 waggle dances from three bee colonies located at two study sites in the urban area of Oslo. The waggle dance is a communication tool of successful foragers to indicate rewarding resource locations to their nestmates. We used this unique behavioural trait to analyse how the used foraging patches of our honeybees are correlated with values of the ESTIMAP model by applying a beta regression model. Moreover, we examined to what extent the foraging patterns of two bee colonies placed in the same environment overlapped. After decoding the dances, the foraging patterns showed that visitation probabilities of used patches were only for one location correlated with the habitat suitability values of the ESTIMAP model. Furthermore, we ascertained that there was also only a mediocre overlap between the foraging patterns of the two hives located next to each other. In general, most of the foraging took place close to the hive locations. With a mean foraging distance of 688 m, 490 m and 425 m respectively, the mean foraging distances of the three urban bee colonies are much shorter than the foraging distances from their colleagues in rural areas. Factors that lead to the moderate correlation between the visitation probabilities of the decoded waggle dances and the ESTIMAP values as well as of the foraging pattern of the hives placed in the same environment can be of various nature. First, by decoding waggle dances we did not have insight where honeybees of other hives or wild pollinators forage. Thus, high suitability habitat patches might have been exploited by other bees. Secondly, human error in the process of decoding the waggle dances might cause some inaccuracy in plotting the foraging patterns of our honeybees. Overall, our study raises more interesting questions about the resource selection of honeybees and suggests that next to the distance and the nectar-reward of the floral resources, also the exploitative competition by other bees might play a role in the resource selection of honeybees

The role of age of first breeding in modeling raptor reintroductions

1. The present biodiversity crisis has led to an increasing number of reintroduction programs, and this conservation method is likely to be increasingly used in the future, especially in the face of climate change. Many fundamental questions in population ecology are focused on the mechanisms through which populations escape extinction. 2. Population viability analysis (PVA) is the most common procedure for analyzing extinction risk. In the use of PVA to model the trajectories of reintroduced populations, demographic values are sometimes taken from other existing wild populations or even from individuals in captivity. 3. Density dependence in productivity is usually considered in viability models, but density‐dependent variation in age of first breeding is usually ignored. Nevertheless, age of first breeding has a buffering effect on population fluctuations and in consequence on population persistence. 4. We simulated the viability of Spanish Imperial Eagle (Aquila adalberti) and Osprey (Pandion haliaetus) populations using data from established and reintroduced populations in southern Spain. 5. Our results show that reduction in the age of first breeding is critical in the success of reintroductions of such long‐lived birds. Additionally, increases in productivity allow populations to growth at maximum rate. However, without considering variation in age of breeding, and the associated increasing overall productivity, reintroduced populations seem nonviable. 6. To ignore density dependence in age of breeding in PVA means that we are seriously limiting the potential of the model population to respond to fluctuations in density, thereby reducing its resilience and viability. Variation in age of first breeding is an important factor that must be considered and included in any simulation model involving long‐lived birds with deferred maturity

Combining morphological and genomic evidence to resolve species diversity and study speciation processes of the Pallenopsis patagonica (Pycnogonida) species complex

Background: Pallenopsis patagonica (Hoek, 1881) is a morphologically and genetically variable sea spider species whose taxonomic classification is challenging. Currently, it is considered as a species complex including several genetic lineages, many of which have not been formally described as species. Members of this species complex occur on the Patagonian and Antarctic continental shelves as well as around sub-Antarctic islands. These habitats have been strongly influenced by historical large-scale glaciations and previous studies suggested that communities were limited to very few refugia during glacial maxima. Therefore, allopatric speciation in these independent refugia is regarded as a common mechanism leading to high biodiversity of marine benthic taxa in the high-latitude Southern Hemisphere. However, other mechanisms such as ecological speciation have rarely been considered or tested. Therefore, we conducted an integrative morphological and genetic study on the P. patagonica species complex to i) resolve species diversity using a target hybrid enrichment approach to obtain multiple genomic markers, ii) find morphological characters and analyze morphometric measurements to distinguish species, and iii) investigate the speciation processes that led to multiple lineages within the species complex. Results: Phylogenomic results support most of the previously reported lineages within the P. patagonica species complex and morphological data show that several lineages are distinct species with diagnostic characters. Two lineages are proposed as new species, P. aulaeturcarum sp. nov. Dömel & Melzer, 2019 and P. obstaculumsuperavit sp. nov. Dömel, 2019, respectively. However, not all lineages could be distinguished morphologically and thus likely represent cryptic species that can only be identified with genetic tools. Further, morphometric data of 135 measurements showed a high amount of variability within and between species without clear support of adaptive divergence in sympatry. Conclusions: We generated an unprecedented molecular data set for members of the P. patagonica sea spider species complex with a target hybrid enrichment approach, which we combined with extensive morphological and morphometric analyses to investigate the taxonomy, phylogeny and biogeography of this group. The extensive data set enabled us to delineate species boundaries, on the basis of which we formally described two new species. No consistent evidence for positive selection was found, rendering speciation in allopatric glacial refugia as the most likely model of speciation

Tailoring ergodicity through selective A-site doping in the Bi1/2Na1/2TiO3-Bi1/2K1/2TiO3 system

The morphotropic phase boundary composition Bi1/2Na1/2TiO3-20 mol. % Bi1/2K1/2TiO3 was chosen as initial material to do selective A-site aliovalent doping replacing Na and K by 1 at. % La, respectively. The materials were studied macroscopically by measuring dielectric and electromechanical properties. The Na-replaced material has a lower freezing temperature Tfr, lower remanent polarization and remanent strain, and thus a higher degree of ergodicity than the K-replaced material. These results are contrasted with local poling experiments and hysteresis loops obtained from piezoresponse force microscopy. The faster relaxation of the tip-induced local polarization and the lower remanent state in bias-on and-off loops confirm the higher degree of ergodicity of the Na-replaced material. The difference in functional properties is attributed to small variations in chemical pressure achieved through selective doping. Raman results support this working hypothesis. ??? 2015 AIP Publishing LLCopen1

The double-stranded DNA-binding proteins TEBP-1 and TEBP-2 form a telomeric complex with POT-1.

Telomeres are bound by dedicated proteins, which protect them from DNA damage and regulate telomere length homeostasis. In the nematode Caenorhabditis elegans, a comprehensive understanding of the proteins interacting with the telomere sequence is lacking. Here, we harnessed a quantitative proteomics approach to identify TEBP-1 and TEBP-2, two paralogs expressed in the germline and embryogenesis that associate to telomeres in vitro and in vivo. tebp-1 and tebp-2 mutants display strikingly distinct phenotypes: tebp-1 mutants have longer telomeres than wild-type animals, while tebp-2 mutants display shorter telomeres and a Mortal Germline. Notably, tebp-1;tebp-2 double mutant animals have synthetic sterility, with germlines showing signs of severe mitotic and meiotic arrest. Furthermore, we show that POT-1 forms a telomeric complex with TEBP-1 and TEBP-2, which bridges TEBP-1/-2 with POT-2/MRT-1. These results provide insights into the composition and organization of a telomeric protein complex in C. elegans

The role of natural science collections in the biomonitoring of environmental contaminants in apex predators in support of the EU's zero pollution ambition

The chemical industry is the leading sector in the EU in terms of added value. However, contaminants pose a major threat and significant costs to the environment and human health. While EU legislation and international conventions aim to reduce this threat, regulators struggle to assess and manage chemical risks, given the vast number of substances involved and the lack of data on exposure and hazards. The European Green Deal sets a 'zero pollution ambition for a toxic free environment' by 2050 and the EU Chemicals Strategy calls for increased monitoring of chemicals in the environment. Monitoring of contaminants in biota can, inter alia: provide regulators with early warning of bioaccumulation problems with chemicals of emerging concern; trigger risk assessment of persistent, bioaccumulative and toxic substances; enable risk assessment of chemical mixtures in biota; enable risk assessment of mixtures; and enable assessment of the effectiveness of risk management measures and of chemicals regulations overall. A number of these purposes are to be addressed under the recently launched European Partnership for Risk Assessment of Chemicals (PARC). Apex predators are of particular value to biomonitoring. Securing sufficient data at European scale implies large-scale, long-term monitoring and a steady supply of large numbers of fresh apex predator tissue samples from across Europe. Natural science collections are very well-placed to supply these. Pan-European monitoring requires effective coordination among field organisations, collections and analytical laboratories for the flow of required specimens, processing and storage of specimens and tissue samples, contaminant analyses delivering pan-European data sets, and provision of specimen and population contextual data. Collections are well-placed to coordinate this. The COST Action European Raptor Biomonitoring Facility provides a well-developed model showing how this can work, integrating a European Raptor Biomonitoring Scheme, Specimen Bank and Sampling Programme. Simultaneously, the EU-funded LIFE APEX has demonstrated a range of regulatory applications using cutting-edge analytical techniques. PARC plans to make best use of such sampling and biomonitoring programmes. Collections are poised to play a critical role in supporting PARC objectives and thereby contribute to delivery of the EU's zero-pollution ambition.Non peer reviewe

Survival and cause-specific mortality of European wildcat (Felis silvestris) across Europe

Humans have transformed most landscapes across the globe, forcing other species to adapt in order to persist in increasingly anthropogenic landscapes. Wide-ranging solitary species, such as wild felids, struggle particularly in such landscapes. Conservation planning and management for their long-term persistence critically depends on understanding what determine survival and what are the main mortality risks. We carried out the first study on annual survival and cause-specific mortality of the European wildcat with a large and unique dataset of 211 tracked individuals from 22 study areas across Europe. Furthermore, we tested the effect of environmental and human disturbance variables on the survival probability. Our results show that mortalities were mainly human-caused, with roadkill and poaching representing 57% and 22% of the total annual mortality, respectively. The annual survival probability of wildcat was 0.92 (95% CI = 0.87–0.98) for females and 0.84 (95% CI = 0.75–0.94) for males. Road density strongly impacted wildcat annual survival, whereby an increase in the road density of motorways and primary roads by 1 km/km2 in wildcat home-ranges increased mortality risk ninefold. Low-traffic roads, such as secondary and tertiary roads, did not significantly affect wildcat's annual survival. Our results deliver key input parameters for population viability analyses, provide planning-relevant information to maintain subcritical road densities in key wildcat habitats, and identify conditions under which wildcat-proof fences and wildlife crossing structures should be installed to decrease wildcat mortality.This research was funded by: the German Federal Ministry of Transport and Digital Infrastructure (BMVI) as part of the mFund project “WilDa—Dynamic Wildlife–Vehicle Collision warning, using heterogeneous traffic, accident and environmental data as well as big data concepts” grant number 19F2014B; the Deutscher Akademischer Austauschdienst (DAAD) Research Grants, Short-Term Grants, 2020 (57507441); the Deutsche Wildtier Stiftung (DeWiSt). The data from Cabañeros National Park were collected in the frame of the project OAPN 352/2011 funded by Organismo Autónomo Parques Nacionales. MM was supported by a research contract Ramón y Cajal from the MINECO (RYC-2015-19231). FDR was supported by a postdoctoral contract funded by the University of Málaga through the grants program “Ayudas para la Incorporación de Doctores del I Plan Propio de Investigación de la Universidad de Málaga (Call 2019)”. PM was supported by UIDB/50027/2020 with funding from FCT/MCTES through national funds.Peer reviewe

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

An assessment of optimal foraging in honeybees through decoding of waggle dances in an urban landscape

A global decline of honeybees (Apis mellifera) and other pollinators which are essential for pollinating crops and wild flowers has been reported throughout the last decades. One major cause is the loss of available resources due to agricultural intensification. Especially urban areas seem to become an important habitat for pollinators. In 2017, Stange et al. developed a habitat suitability model for pollinators indicating habitat quality in terms of available floral resources and nesting sites for the City of Oslo, Norway. Our aim was to analyse whether the foraging patterns of honeybees match with highly suitable habitat patches as indicated by the ESTIMAP model. According to the optimal foraging theory honeybees should visit the closest and most rewarding habitat patches from the hive location, maximizing energetic intake per unit time. Hence, we hypothesised that patches which were frequently visited by the studied honeybees also had a high habitat suitability value and vice versa. We studied honeybee foraging patterns over the summer 2017 by decoding 506 waggle dances from three bee colonies located at two study sites in the urban area of Oslo. The waggle dance is a communication tool of successful foragers to indicate rewarding resource locations to their nestmates. We used this unique behavioural trait to analyse how the used foraging patches of our honeybees are correlated with values of the ESTIMAP model by applying a beta regression model. Moreover, we examined to what extent the foraging patterns of two bee colonies placed in the same environment overlapped. After decoding the dances, the foraging patterns showed that visitation probabilities of used patches were only for one location correlated with the habitat suitability values of the ESTIMAP model. Furthermore, we ascertained that there was also only a mediocre overlap between the foraging patterns of the two hives located next to each other. In general, most of the foraging took place close to the hive locations. With a mean foraging distance of 688 m, 490 m and 425 m respectively, the mean foraging distances of the three urban bee colonies are much shorter than the foraging distances from their colleagues in rural areas. Factors that lead to the moderate correlation between the visitation probabilities of the decoded waggle dances and the ESTIMAP values as well as of the foraging pattern of the hives placed in the same environment can be of various nature. First, by decoding waggle dances we did not have insight where honeybees of other hives or wild pollinators forage. Thus, high suitability habitat patches might have been exploited by other bees. Secondly, human error in the process of decoding the waggle dances might cause some inaccuracy in plotting the foraging patterns of our honeybees. Overall, our study raises more interesting questions about the resource selection of honeybees and suggests that next to the distance and the nectar-reward of the floral resources, also the exploitative competition by other bees might play a role in the resource selection of honeybees

An assessment of optimal foraging in honeybees through decoding of waggle dances in an urban landscape

A global decline of honeybees (Apis mellifera) and other pollinators which are essential for pollinating crops and wild flowers has been reported throughout the last decades. One major cause is the loss of available resources due to agricultural intensification. Especially urban areas seem to become an important habitat for pollinators. In 2017, Stange et al. developed a habitat suitability model for pollinators indicating habitat quality in terms of available floral resources and nesting sites for the City of Oslo, Norway. Our aim was to analyse whether the foraging patterns of honeybees match with highly suitable habitat patches as indicated by the ESTIMAP model. According to the optimal foraging theory honeybees should visit the closest and most rewarding habitat patches from the hive location, maximizing energetic intake per unit time. Hence, we hypothesised that patches which were frequently visited by the studied honeybees also had a high habitat suitability value and vice versa. We studied honeybee foraging patterns over the summer 2017 by decoding 506 waggle dances from three bee colonies located at two study sites in the urban area of Oslo. The waggle dance is a communication tool of successful foragers to indicate rewarding resource locations to their nestmates. We used this unique behavioural trait to analyse how the used foraging patches of our honeybees are correlated with values of the ESTIMAP model by applying a beta regression model. Moreover, we examined to what extent the foraging patterns of two bee colonies placed in the same environment overlapped. After decoding the dances, the foraging patterns showed that visitation probabilities of used patches were only for one location correlated with the habitat suitability values of the ESTIMAP model. Furthermore, we ascertained that there was also only a mediocre overlap between the foraging patterns of the two hives located next to each other. In general, most of the foraging took place close to the hive locations. With a mean foraging distance of 688 m, 490 m and 425 m respectively, the mean foraging distances of the three urban bee colonies are much shorter than the foraging distances from their colleagues in rural areas. Factors that lead to the moderate correlation between the visitation probabilities of the decoded waggle dances and the ESTIMAP values as well as of the foraging pattern of the hives placed in the same environment can be of various nature. First, by decoding waggle dances we did not have insight where honeybees of other hives or wild pollinators forage. Thus, high suitability habitat patches might have been exploited by other bees. Secondly, human error in the process of decoding the waggle dances might cause some inaccuracy in plotting the foraging patterns of our honeybees. Overall, our study raises more interesting questions about the resource selection of honeybees and suggests that next to the distance and the nectar-reward of the floral resources, also the exploitative competition by other bees might play a role in the resource selection of honeybees