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Analysis of three wild-caught bumblebee species shows that family lineage survival and persistence is significantly increased between successive colony cycle stages with the proportion of high-value foraging habitat near the natal colony. Queen bee conservation Agricultural intensification is a major cause of the global decline in insect pollinators. In this UK-based field experiment, Claire Carvell and colleagues show that bumblebee colonies located close to high-value foraging habitats, including spring floral resources, are more likely to produce daughter queens that survive winter hibernation and emerge in the spring to start a new colony. Their findings add to the evidence that conservation interventions targeted at the landscape level have a positive effect on wild pollinators in agricultural settings. Insect pollinators such as bumblebees ( Bombus spp.) are in global decline 1 , 2 . A major cause of this decline is habitat loss due to agricultural intensification 3 . A range of global and national initiatives aimed at restoring pollinator habitats and populations have been developed 4 , 5 . However, the success of these initiatives depends critically upon understanding how landscape change affects key population-level parameters, such as survival between lifecycle stages 6 , in target species. This knowledge is lacking for bumblebees, because of the difficulty of systematically finding and monitoring colonies in the wild. We used a combination of habitat manipulation, land-use and habitat surveys, molecular genetics 7 and demographic and spatial modelling to analyse between-year survival of family lineages in field populations of three bumblebee species. Here we show that the survival of family lineages from the summer worker to the spring queen stage in the following year increases significantly with the proportion of high-value foraging habitat, including spring floral resources, within 250–1,000 m of the natal colony. This provides evidence for a positive impact of habitat quality on survival and persistence between successive colony cycle stages in bumblebee populations. These findings also support the idea that conservation interventions that increase floral resources at a landscape scale and throughout the season have positive effects on wild pollinators in agricultural landscapes.

Bumble bees (Bombus spp.) are important pollinators of both crops and wildflowers. Their contribution to this essential ecosystem service has been threatened over recent decades by changes in land use, which have led to declines in their populations. In order to design effective conservation measures, it is important to understand the effects of variation in landscape composition and structure on the foraging activities of worker bumble bees. This is because the viability of individual colonies is likely to be affected by the trade‐off between the energetic costs of foraging over greater distances and the potential gains from access to additional resources. We used field surveys, molecular genetics, and fine resolution remote sensing to estimate the locations of wild bumble bee nests and to infer foraging distances across a 20‐km² agricultural landscape in southern England, UK. We investigated five species, including the rare B. ruderatus and ecologically similar but widespread B. hortorum. We compared worker foraging distances between species and examined how variation in landscape composition and structure affected foraging distances at the colony level. Mean worker foraging distances differed significantly between species. Bombus terrestris, B. lapidarius, and B. ruderatus exhibited significantly greater mean foraging distances (551, 536, and 501 m, respectively) than B. hortorum and B. pascuorum (336 and 272 m, respectively). There was wide variation in worker foraging distances between colonies of the same species, which was in turn strongly influenced by the amount and spatial configuration of available foraging habitats. Shorter foraging distances were found for colonies where the local landscape had high coverage and low fragmentation of seminatural vegetation, including managed agri‐environmental field margins. The strength of relationships between different landscape variables and foraging distance varied between species, for example the strongest relationship for B. ruderatus being with floral cover of preferred forage plants. Our findings suggest that management of landscape composition and configuration has the potential to reduce foraging distances across a range of bumble bee species. There is thus potential for improvements in the design and implementation of landscape management options, such as agri‐environment schemes, aimed at providing foraging habitat for bumble bees and enhancing crop pollination services.

In many species, females store sperm between copulation and egg fertilization, but the consequences of sperm storage and patterns of sperm use for female life history and reproductive success have not been investigated in great detail. In hymenopteran insect societies (ants, bees, wasps), reproduction is usually monopolized by one or relatively few queens, who mate only during a brief period early in life and store sperm for later use. The queens of some ants are particularly long-lived and have the potential to produce millions of offspring during their life. To do so, queens store many sperm cells, and this sperm must remain viable throughout the years of storage. Queens should also be under strong selection to use stored sperm prudently when fertilizing eggs. We used the leaf-cutter ant Atta colombica to investigate the dynamics of sperm use during egg fertilization. We show that queens are able to fertilize close to 100 per cent of the eggs and that the average sperm use per egg is very low, but increases with queen age. The robustness of stored sperm was found to decrease with years of storage, signifying that senescence affects sperm either directly or indirectly via the declining glandular secretions or deteriorating sperm-storage organs. We evaluate our findings with a heuristic model, which suggests that the average queen has sperm for almost 9 years of normal colony development. We discuss the extent to which leaf-cutter ant queens have been able to optimize their sperm expenditure and infer that our observed averages of sperm number, sperm robustness and sperm use are consistent with sperm depletion being a significant cause of mortality of mature colonies of Atta leaf-cutter ants.

Moral paradigms are fundamental to most works of fantasy fiction. Two moral standpoints dominate recent Russian fantasy fiction and film: individualism and collectivism. Individualism believes in the superior value of personal experience, whereas collectivism prioritizes the benefit to the group. This article contrasts Sergei Luk'ianenko's novella \"Destiny\" (Svoia sud'ba) with Timur Bekmambetov's film adaptation Night Watch (Nochnoi dozor) to demonstrate that the moral paradigms of individualism and collectivism can be tied respectively to urban and epic subgenres of fantasy fiction. The author demonstrates that an inclination toward individualism in the urban \"Destiny\" and toward collectivism in the epic Night Watch leads to contrasting representations of alterity in the works. Individualist and collectivist orientations affect how the works comment on the human tendency to discriminate between oneself and others. The author uses examples from \"Destiny\" and Night Watch to argue that the narrative strategies associated with urban fantasy promote inclusive paradigms of alterity, whereas those associated with epic fantasy tend to advance confrontational mentalities.

Social insects offer unique opportunities to test predictions regarding the evolution of cooperation, life histories and communication. Colony founding by groups of unrelated queens, some of which are later killed, may select for selfish reproductive strategies, honest signalling and punishment. Here, we use a brood transfer experiment to test whether cofounding queens of the ant Lasius niger ‘selfishly’ adjust their productivity when sharing the nest with future competitors. We simultaneously analysed queen cuticular hydrocarbon (CHC) profiles to investigate whether queens honestly signal their reproductive output or produce dishonest, manipulative signals, providing a novel test of the evolutionary significance of queen pheromones. Queens produced fewer workers when their colony contained ample brood, but only in the presence of competitors, suggesting selfish conservation of resources. Several CHCs correlated with reproductive maturation, and to a lesser extent with productivity; the same hydrocarbons were more abundant on queens that were not killed, suggesting that workers select productive queens using these chemical cues. Our results highlight the role of honest signalling in the evolution of cooperation: whenever cheaters can be reliably identified, they may incur sanctions that reduce the incentive to be selfish.

The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats. We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits. These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation.