Searching for the Genetic Basis of Hygienic Behavior and Overwintering in the Honeybee (Apis mellifera)

The recent decline in honeybee populations can be mitigated through genomics and marker-assisted selection. The current techniques, such as chemical treatment to prevent disease, are only short-term solutions. The ability to breed honeybees that are disease and winter resistant would be ideal. Current breeding techniques lack knowledge of predictive markers that may improve these traits. Here we perform a genome-wide association study on 925 colonies by measuring hygienic and overwintering behavior of the colonies, followed by sequencing their genomes. L1 regression is a technique developed to pick the best Single Nucleotide Polymorphisms that explain the variance in the phenotype. Using L1 regression, we found 27 Single Nucleotide Polymorphisms for hygiene and 32 Single Nucleotide Polymorphisms for overwintering behaviour that could be used to breed for healthier and winter hardy honeybees

Conservation Genomics of the Declining North American Bumblebee Bombus terricola Reveals Inbreeding and Selection on Immune Genes

The yellow-banded bumblebee Bombus terricola was common in North America but has recently declined and is now on the IUCN Red List of threatened species. The causes of B. terricola’s decline are not well understood. Our objectives were to create a partial genome and then use this to estimate population data of conservation interest, and to determine whether genes showing signs of recent selection suggest a specific cause of decline. First, we generated a draft partial genome (contig set) for B. terricola, sequenced using Pacific Biosciences RS II at an average depth of 35×. Second, we sequenced the individual genomes of 22 bumblebee gynes from Ontario and Quebec using Illumina HiSeq 2500, each at an average depth of 20×, which were used to improve the PacBio genome calls and for population genetic analyses. The latter revealed that several samples had long runs of homozygosity, and individuals had high inbreeding coefficient F, consistent with low effective population size. Our data suggest that B. terricola’s effective population size has decreased orders of magnitude from pre-Holocene levels. We carried out tests of selection to identify genes that may have played a role in ameliorating environmental stressors underlying B. terricola’s decline. Several immune-related genes have signatures of recent positive selection, which is consistent with the pathogen-spillover hypothesis for B. terricola’s decline. The new B. terricola contig set can help solve the mystery of bumblebee decline by enabling functional genomics research to directly assess the health of pollinators and identify the stressors causing declines

Gender Differences in Second-Level Schooling

This thesis is concerned with gender differences in Irish secondlevel schooling. The problems generated by this type of genderdifferentiation are identified in the maintenance of sex-stereotyped career choices, the status associated with each sex in the labour force, the division of labour in the home and the contribution of the sexes to the general construction of knowledge. The extent to which gender differences exist in schools and in school-related activities is established, and it is shown that considerable variation exists between boys’ and girls’ subject choices and career expectations. It is also revealed that boys’ and girls’ extracurricular activities tend to be determined on the basis of their sex. It is subsequently shown that both sexes perceive and reject the school’s attempt to channel them into sex-stereotyped roles; the extent of this rejection is limited to verbal disagreement as the pupils have limited opportunity to express overt resistance. Finally, the findings indicate that the gender differences in the pupils’ behaviour and attitudes can be attributed to the influence of the home and the peer-group. It is discovered that the pupils do not perceive this influence as readily as they perceive gender-differentiation in the school