Andrew Bourke's Website
As well as conducting research (see here and here), I enjoy pursuing interests in all kinds of natural history, including observing and recording insects (see here and here) and bird watching (see here and here). I also enjoy fossil collecting (see here). So this website is about both my research and these other interests.
SELECTED NATURAL HISTORY HIGHLIGHTS
CATTLE EGRET IN NORFOLK: I am still getting used to the sight of Cattle Egrets in the UK. This one was at St Benet's Abbey, near Ludham, Norfolk, December 2024.
SPARROWHAWK WITH CAPTURED SWIFT: A male Sparrowhawk with a captured Swift on our lawn last spring. I was very surprised to see a Swift as prey in this way, but have since read that Sparrowhawk predation of Swifts is known to occur, but rare. Norwich, Norfolk, May 2024.
SELECTED RESEARCH PAPER HIGHLIGHTS
COSTS OF REPRODUCTION IN EUSOCIAL INSECT QUEENS: In a paper in BMC Biology, we tested whether queens in annual eusocial insects like the bumble bee Bombus terrestris experience costs of reproduction. We experimentally increased queens’ costs of reproduction by removing their eggs, which caused queens to increase their egg-laying rate. Treatment queens lived significantly shorter lives than control queens whose egg-laying rate was not increased. In addition, treatment and control queens differed in age-related gene expression in both their overall expression profiles and the expression of ageing-related genes. These findings suggest that costs of reproduction are present but latent, i.e. that positive fecundity-longevity associations in queens of B. terrestris and similar species are condition-dependent. They also raised the possibility that a partial remodelling of genetic and endocrine networks underpinning ageing may have occurred in B. terrestris such that, in unmanipulated conditions, age-related gene expression depends more on chronological than relative age.
The paper is: Collins DH, Prince DC, Donelan JL, Chapman T, Bourke AFG (2023) Costs of reproduction are present but latent in eusocial bumblebee queens. BMC Biology 21: 153.
CONFLICT OVER RESOURCE INHERITANCE: In this paper in American Naturalist, we developed a model of queen-worker conflict over nest inheritance and tested it in the bumble bee Bombus terrestris. As the model predicted, we showed that workers harass queens with simulated fecundity loss and that aggressive workers are more likely to become egg-layers. This is consistent with workers monitoring queen fecundity to weigh up the relative benefits of reproducing in the nest after the queen's death versus continuing to keep the queen alive as a source of siblings. These findings provide new support for kin-selected conflict over resource inheritance being a key process in social animals.
The paper is: Almond EJ, Huggins TJ, Crowther LP, Parker JD, Bourke AFG (2019) Queen longevity and fecundity affect conflict with workers over resource inheritance in a social insect. American Naturalist 193: 256-266.