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A defining characteristic of eusocial animals is their division of labour into reproductive and nonreproductive specialists. Here, we used a microarray study to identify genes associated with functional sterility in the worker honey bee Apis mellifera. We contrasted gene expression in workers from a functionally sterile wild-type strain with that in a mutant (anarchist) strain selected for high rates of ovary activation. We identified a small set of genes from the brain ( n = 7) and from the abdomen ( n = 5) that are correlated in their expression with early stages of ovary activation. Sterile wild-type workers up-regulated two unknown genes and a homologue of Drosophila CG6004. By contrast, reproductive anarchist workers up-regulated genes for the yolk protein vitellogenin, venom peptides and a member of the AdoHycase superfamily, among others. The differentially expressed genes identified are likely to be involved in early differentiation into sterile and reproductive worker phenotypes and may therefore form part of the gene networks associated with the regulation of honey bee worker sterility. Our study may have lacked sufficient power to detect all but a minority of biologically relevant changes taking place; however, the differential expression of vitellogenin and a putative AdoHycase suggests that our screen has captured core reproductive genes and that ovary activation may involve an epigenetic mechanism. [ABSTRACT FROM AUTHOR]

We show that differences in the reproductive development of honey bee workers are associated with locus-specific changes to abundance of messenger RNA. Using a cross-fostering field experiment to control for differences related to age and environment, we compared the gene expression profiles of functionally sterile workers (wild-type) and those from a mutant strain in which workers are reproductively active (anarchist). Among the set of three genes that are significantly differentially expressed are two major royal jelly proteins that are up-regulated in wild-type heads. This discovery is consistent with sterile workers synthesizing royal jelly as food for developing brood. Likewise, the relative underexpression of these two royal jellies in anarchist workers is consistent with these workers’ characteristic avoidance of alloparental behaviour, in favour of selfish egg-laying. Overall, there is a trend for the most differentially expressed genes to be up-regulated in wild-type workers. This pattern suggests that functional sterility in honey bee workers may generally involve the expression of a suite of genes that effectively ‘switch’ ovaries off, and that selfish reproduction in honey bee workers, though rare, is the default developmental pathway that results when ovary activation is not suppressed. [ABSTRACT FROM AUTHOR]

Phylogenetic analysis based on sequence variation in mitochondrial large-subunit rRNA and cytochrome oxidase II genes was used to investigate the evolutionary relationships among termite families. Maximum likelihood and parsimony analyses of a combined nucleotide data set yield a single well-supported topology, which is: (((((Termitidae, Rhinotermitidae), Serritermitidae), Kalotermitidae), (Hodotermitidae, Termopsidae)), Mastotermitidae). Although some aspects of this topology are consistent with previous schemes, overall it differs from any published. Optimization of ‘true’ workers onto the tree suggests that this caste originated once, early in the history of the lineage and has been lost secondarily twice. This scenario differs from the more widely accepted notion that workers are derived and of polyphyletic origin and that extant pseudergates, or ‘false’ workers, are their developmentally unspecialized ancestor caste. Worker gains and losses covary directly in number and direction with shifts in ‘ecological life type’. A test for correlated evolution which takes phylogenetic structure into account indicates that this pattern is of biological significance and suggests that the variable occurrence of a worker caste in termites has ecological determinants, apparently linked to differences in feeding and nesting habits. [ABSTRACT FROM AUTHOR]

The article presents the research paper which reflects on methods used by the Freshwater Biological Association to reduce the number of pike in Lake Windermere, England. Pikes reduced the food for the trouts, which are the most important fishes in the lake. The study found out that the long lining method caught more pikes but also eels and trout which could not be returned alive.

Reports on the characterization of microsatellite markers for the Termitidae. Restriction of genomic DNA with double-digest combinations; Isolation of clones; Extraction of genomic DNA for microsatellite analysis from the heads of single individuals using the Chelex protocol.

Queen mandibular pheromone (QMP) is a potent reproductive signal to which honey bee workers respond by suppressing their ovaries and adopting alloparental roles within the colony. This anti‐ovarian effect of QMP on workers can, surprisingly, be induced in other insects, including fruit flies, in which females exposed to synthetic QMP develop smaller ovaries with fewer eggs. In this study, we use the Drosophila melanogaster model to identify the components of synthetic QMP required for the anti‐ovarian effect. We found that virgin females respond strongly to 9‐oxo‐2‐decenoic acid and 10‐hydroxy‐2‐decenoic acid (10HDA), suggesting that the decenoic acid components of QMP are essential for the anti‐ovarian response. Further, a nuclear factor of activated T‐cells reporter system revealed neurones expressing the olfactory receptors Or‐56a, Or‐49b and Or‐98a are activated by QMP in the antenna. In addition, we used olfactory receptor GAL4 drivers and a neuronal activator (a neuronal activating bacterial sodium channel) to test whether the candidate neurones are potential labelled lines for a decenoic acid response. We identified Or‐49b as a potential candidate receiver of the 10HDA signal. Finally, the anti‐ovarian response to synthetic QMP is not mediated by decreasing the titre of the reproductive hormones ecdysone and juvenile hormone. [ABSTRACT FROM AUTHOR]

Social insects are able to mount both group-level and individual defences against pathogens. Here we focus on individual defences, by presenting a genome-wide analysis of immunity in a social insect, the honey bee Apis mellifera. We present honey bee models for each of four signalling pathways associated with immunity, identifying plausible orthologues for nearly all predicted pathway members. When compared to the sequenced Drosophila and Anopheles genomes, honey bees possess roughly one-third as many genes in 17 gene families implicated in insect immunity. We suggest that an implied reduction in immune flexibility in bees reflects either the strength of social barriers to disease, or a tendency for bees to be attacked by a limited set of highly coevolved pathogens. [ABSTRACT FROM AUTHOR]