GENE EXPRESSION in queen and worker bumble bees: In a recent paper, we've used qRT-PCR in the bumble bee Bombus terrestris to investigate expression levels of four widely conserved ageing-related genes as a function of individuals' age and social environment. We found that workerless queens showed higher foraging (for) expression, as predicted if foundress queens downregulate for when they cease to forage once their workers have emerged. Older workers showed higher DNA methyltransferase 3 (Dnmt3) expression, suggesting a novel association between ageing and methylation. Ovary activation was associated with higher vitellogenin (vg) expression in workers, especially younger ones, consistent with vitellogenin's ancestral role in regulating egg production. Overall, our findings reveal a mixture of novel and conserved features in age-related genetic pathways in bumble bees. This study is published in Experimental Gerontology (Lockett GA, Almond EJ [joint first authors], Huggins TJ, Parker JD, Bourke AFG. 2016. Gene expression differences in relation to age and social environment in queen and worker bumble bees. Experimental Gerontology 77: 52-61). View article
WORKER MATRICIDE: In a fine new study, Kevin Loope (Cornell University) has shown for the first time that workers in an annual social insect, the wasp Dolichovespula arenaria, preferentially kill their mother queen in colonies in which they are most closely related to their own potential male offspring, as predicted by inclusive fitness theory. The image (courtesy of Kevin Loope) shows a marked queen D. arenaria in her nest. The study is published in Current Biology (Loope KJ. 2015. Queen killing is linked to high worker-worker relatedness in a social wasp. Current Biology 25: 2976-2979) with a commentary article by myself. View articleView commentary
CONGRATULATIONS to former group member Jacob Holland, whose paper on the effects of temperature on longevity and life history in bumble bees, based on research carried out during his PhD at UEA, was recently published in Functional Ecology (Holland JG, Bourke AFG. 2015. Colony and individual life-history responses to temperature in a social insect pollinator. Functional Ecology 29: 1209-1217). Jacob is now a postdoc in Guy Bloch's group at the Hebrew University of Jerusalem. View article
MY CRITIQUE of recent arguments that patterns of sex investment ratios in ants and other social insects can be adequately explained without invoking inclusive fitness theory has now been published (Bourke AFG. 2015. Sex investment ratios in eusocial Hymenoptera support inclusive fitness theory. Journal of Evolutionary Biology 28: 2106-2111). View article
Social evolution is a fundamental topic in evolutionary biology and behavioural ecology because it shows how natural selection acting on selfish genes can lead to cooperative behaviour. In addition, by explaining why individuals group together to form new levels of organization (such as genomes within cells, cells within organisms and organisms within societies), social evolution lies at the heart of our understanding of the major transitions in evolution.
The social insects such as the ants, bees and wasps represent perfect subjects for the study of social evolution because of the rich diversity of their social systems and the extreme nature of some of their social behaviour. Social insects also play a crucial role in delivering ecosystem services such as pollination, making the continued health of social insect populations a top priority.
Accordingly, my research interests fall into two main areas:
I am interested in the evolutionary, ecological, behavioural and genetic basis of social behaviour. In particular, using ants and the bumble bee Bombus terrestris, I conduct empirical studies to test hypotheses from inclusive fitness (kin selection) theory. I am also interested in conceptual, synthetic and empirical studies that apply insights from the study of social evolution to related domains, examples being the evolution of ageing and the major transitions in evolution.
I conduct applied research (much of it with external collaborators) in social insect conservation biology, including such topics as the assessment of agri-environment schemes for bumble bees and the conservation genetics of scarce or declining social insects. A particular focus is on developing genetic methods for censusing wild populations of bees with a view to aiding conservation initiatives for these threatened pollinators.