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"William C. Jordan"
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Bumblebee family lineage survival is enhanced in high-quality landscapes
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.
Journal Article
The apple of his eye : converts from islam in the reign of Louis IX
The thirteenth century brought new urgency to Catholic efforts to convert non-Christians, and no Catholic ruler was more dedicated to this undertaking than King Louis IX of France. His military expeditions against Islam are well documented, but there was also a peaceful side to his encounter with the Muslim world, one that has received little attention until now. This splendid book shines new light on the king's program to induce Muslims - the \"apple of his eye\" - to voluntarily convert to Christianity and resettle in France. It recovers a forgotten but important episode in the history of the Crusades while providing a rare window into the fraught experiences of the converts themselves. William Chester Jordan transforms our understanding of medieval Christian-Muslim relations by telling the stories of the Muslims who came to France to live as Christians. Under what circumstances did they willingly convert? How successfully did they assimilate into French society? What forms of resistance did they employ? In examining questions like these, Jordan weaves a richly detailed portrait of a dazzling yet violent age whose lessons still resonate today. Until now, scholars have dismissed historical accounts of the king's peaceful conversion of Muslims as hagiographical and therefore untrustworthy. Jordan takes these narratives seriously--and uncovers archival evidence to back them up. He brings his findings marvelously to life in this succinct and compelling book, setting them in the context of the Seventh Crusade and the universalizing Catholic impulse to convert the world.
Book
Effects of habitat composition and landscape structure on worker foraging distances of five bumble bee species
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 tradeâoff 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 20âkm² 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 agriâenvironmental 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 agriâenvironment schemes, aimed at providing foraging habitat for bumble bees and enhancing crop pollination services.
Journal Article
REPRODUCTIVE CONFLICT IN BUMBLEBEES AND THE EVOLUTION OF WORKER POLICING
Worker policing (mutual repression of reproduction) in the eusocial Hymenoptera represents a leading example of how coercion can facilitate cooperation. The occurrence of worker policing in \"primitively\" eusocial species with low mating frequencies, which lack relatedness differences conducive to policing, suggests that separate factors may underlie the origin and maintenance of worker policing. We tested this hypothesis by investigating conflict over male parentage in the primitively eusocial, monandrous bumblebee, Bombus terrestris. Using observations, experiments, and microsatellite genotyping, we found that: (a) worker- but not queen-laid male eggs are nearly all eaten (by queens, reproductive, and nonreproductive workers) soon after being laid, so accounting for low observed frequencies of larval and adult worker-produced males; (b) queen- and worker-laid male eggs have equal viabilities; (c) workers discriminate between queen- and worker-laid eggs using cues on eggs and egg cells that almost certainly originate from queens. The cooccurrence in B. terrestris of these three key elements of \"classical\" worker policing as found in the highly eusocial, polyandrous honeybees provides novel support for the hypothesis that worker policing can originate in the absence of relatedness differences maintaining it. Worker policing in B. terrestris almost certainly arose via reproductive competition among workers, that is, as \"selfish\" policing.
Journal Article
Knights, Lords, and Ladies : In Search of Aristocrats in the Paris Region, 1180-1220
\"An examination of the aristocracy of the Paris region during the reign of Philip Augustus\"-- Provided by publisher.
Book
Social parasitism by male-producing reproductive workers in a eusocial insect
The evolution of extreme cooperation, as found in eusocial insects (those with a worker caste), is potentially undermined by selfish reproduction among group members. In some eusocial Hymenoptera (ants, bees and wasps), workers can produce male offspring from unfertilized eggs. Kin selection theory predicts levels of worker reproduction as a function of the relatedness structure of the workers' natal colony and the colony-level costs of worker reproduction. However, the theory has been only partially successful in explaining levels of worker reproduction. Here we show that workers of a eusocial bumble bee (Bombus terrestris) enter unrelated, conspecific colonies in which they then produce adult male offspring, and that such socially parasitic workers reproduce earlier and are significantly more reproductive and aggressive than resident workers that reproduce within their own colonies. Explaining levels of worker reproduction, and hence the potential of worker selfishness to undermine the evolution of cooperation, will therefore require more than simply a consideration of the kin-selected interests of resident workers. It will also require knowledge of the full set of reproductive options available to workers, including intraspecific social parasitism.
Journal Article
Differential gene expression and phenotypic plasticity in behavioural castes of the primitively eusocial wasp, Polistes canadensis
Understanding how a single genome can produce a variety of different phenotypes is of fundamental importance in evolutionary and developmental biology. One of the most striking examples of phenotypic plasticity is the female caste system found in eusocial insects, where variation in reproductive (queens) and non-reproductive (workers) phenotypes results in a broad spectrum of caste types, ranging from behavioural through to morphological castes. Recent advances in genomic techniques allow novel comparisons on the nature of caste phenotypes to be made at the level of the genes in organisms for which there is little genome information, facilitating new approaches in studying social evolution and behaviour. Using the paper wasp Polistes canadensis as a model system, we investigated for the first time how behavioural castes in primitively eusocial insect societies are associated with differential expression of shared genes. We found that queens and newly emerged females express gene expression patterns that are distinct from each other whilst workers generally expressed intermediate patterns, as predicted by Polistes biology. We compared caste-associated genes in P. canadensis with those expressed in adult queens and workers of more advanced eusocial societies, which represent four independent origins of eusociality. Nine genes were conserved across the four taxa, although their patterns of expression and putative functions varied. Thus, we identify several genes that are putatively of evolutionary importance in the molecular biology that underlies a number of caste systems of independent evolutionary origin.
Journal Article
Phylogenetic Relationships in Pterodroma Petrels Are Obscured by Recent Secondary Contact and Hybridization
The classification of petrels (Pterodroma spp.) from Round Island, near Mauritius in the Indian Ocean, has confounded researchers since their discovery in 1948. In this study we investigate the relationships between Round Island petrels and their closest relatives using evidence from mitochondrial DNA sequence data and ectoparasites. Far from providing clear delimitation of species boundaries, our results reveal that hybridization among species on Round Island has led to genetic leakage between populations from different ocean basins. The most common species on the island, Pterodroma arminjoniana, appears to be hybridizing with two rarer species (P. heraldica and P. neglecta), subverting the reproductive isolation of all three and allowing gene flow. P. heraldica and P. neglecta breed sympatrically in the Pacific Ocean, where P. arminjoniana is absent, but no record of hybridization between these two exists and they remain phenotypically distinct. The breakdown of species boundaries in Round Island petrels followed environmental change (deforestation and changes in species composition due to hunting) within their overlapping ranges. Such multi-species interactions have implications not only for conservation, but also for our understanding of the processes of evolutionary diversification and speciation.
Journal Article