G. Bourke results 28
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Identification of two mutant JASON-RELATED genes associated with unreduced pollen production in potatoNARA Subscribed
Key message Multiple QTLs control unreduced pollen production in potato. Two major-effect QTLs co-locate with mutant alleles of genes with homology to AtJAS, a known regulator of meiotic spindle orientation. Abstract In diploid potato the production of unreduced gametes with a diploid (2 n ) rather than a haploid ( n ) number of chromosomes has been widely reported. Besides their evolutionary important role in sexual polyploid...
Implementing post-normal science with or for EU policy actors: using quantitative story-tellingNARA Subscribed
There is increasing recognition of the wicked nature of the intertwined climate, biodiversity and economic crises, and the need for adaptive, multi-scale approaches to understanding the complexity of both the problems and potential responses. Most science underpinning policy responses to sustainability issues, however, remains overtly apolitical and focussed on technical innovation; at odds with a critical body of literatures...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Key message In polyploids, linkage mapping is carried out using genotyping with discrete dosage scores. Here, we use probabilistic genotypes and we validate it for the construction of polyploid linkage maps. Abstract Marker genotypes are generally called as discrete values: homozygous versus heterozygous in the case of diploids, or an integer allele dosage in the case of polyploids. Software for linkage map construction and/or...
The queen‐worker caste system of eusocial insects represents a prime example of developmental polyphenism (environmentally‐induced phenotypic polymorphism) and is intrinsic to the evolution of advanced eusociality. However, the comparative molecular basis of larval caste determination and subsequent differentiation in the eusocial Hymenoptera remains poorly known. To address this issue within bees, we profiled caste‐associated...
Morphological and physiological responses of the potato stem transport tissues to dehydration stressNARA Subscribed
Main conclusion Adaptation of the xylem under dehydration to smaller sized vessels and the increase in xylem density per stem area facilitate water transport during water-limiting conditions, and this has implications for assimilate transport during drought. Abstract The potato stem is the communication and transport channel between the assimilate-exporting source leaves and the terminal sink tissues of the plant. During envir...
Multilocus phylogeography reveals nested endemism in a gecko across the monsoonal tropics of AustraliaNARA Subscribed
Multilocus phylogeography can uncover taxonomically unrecognized lineage diversity across complex biomes. The Australian monsoonal tropics include vast, ecologically intact savanna‐woodland plains interspersed with ancient sandstone uplands. Although recognized in general for its high species richness and endemism, the biodiversity of the region remains underexplored due to its remoteness. This is despite a high rate of ongoin...
Fine‐scale spatial genetic structure of common and declining bumble bees across an agricultural landscapeNARA Subscribed
Land‐use changes have threatened populations of many insect pollinators, including bumble bees. Patterns of dispersal and gene flow are key determinants of species' ability to respond to land‐use change, but have been little investigated at a fine scale ( Bombus species ( B. terrestris , B. lapidarius , B. pascuorum and B. hortorum ) and one declining species ( B. ruderatus ) in an agricultural landscape in Southern England, U...
Conservation genetics, foraging distance and nest density of the scarce Great Yellow Bumblebee ( Bombus distinguendus )NARA Subscribed
The conservation genetics of bees is of particular interest because many bee species are in decline, so jeopardizing the essential ecosystem service of plant pollination that they provide. In addition, as social haplodiploids, inbred bees may be vulnerable to the extra genetic load represented by the production of sterile diploid males. Using microsatellite markers, we investigated the genetic structure of populations of the G...
Genetic analysis of spatial foraging patterns and resource sharing in bumble bee pollinatorsNARA Subscribed
Conservation biologists, evolutionary ecologists and agricultural biologists require an improved understanding of how pollinators utilize space and share resources. Using microsatellite markers, we conducted a genetic analysis of space use and resource sharing at several spatial scales among workers of two ecologically dissimilar bumble bee species ( Bombus terrestris and B. pascuorum ) foraging in an urban landscape (London,...
Social insects (ants, bees, wasps and termites) as a group are species rich and ecologically dominant. Many are outstanding “ecological engineers”, or providers of “ecosystem services”, or potential bioindicator species. Few social insects are currently formally classified as Threatened, but this is almost certainly due to a lack of information on population sizes and trends in scarce species. The main influence that sociality...
Multiple mating by queens (polyandry) and the occurrence of multiple queens in the same colony (polygyny) alter patterns of relatedness within societies of eusocial insects. This is predicted to influence kin‐selected conflicts over reproduction. We investigated the mating system of a facultatively polygynous UK population of the ant Leptothorax acervorum using up to six microsatellite loci. We estimated mating frequency by ge...