*NERC E4* Social and transgenerational effects of parasitism: could they affect biological control of a stored product pest?

Interested individuals must follow the "how to apply" link on the Geosciences E4 Doctoral Training Partnership web page: http://www.ed.ac.uk/e4-dtp/how-to-apply

Parasites are a ubiquitous component of an organism’s environment and parasitic infection can have a dramatic effect on the behaviour and fitness of the infected individual. Organisms are therefore expected to evolve behavioural and life history strategies that allow them to maximise fitness in the face of parasitic attack. These strategies potentially have consequences for the dynamics of populations and hence understanding how different factors affect these decisions can be key in understanding the long term fate of populations which we might wish to conserve or eradicate.
This project aims to examine how infection affects reproductive investment and life-history trade-offs and the subsequent transgenerational impact of infection via sex-specific effects of parasitism on sons and daughters. It will use the bean beetle, C. maculatus as a model organism: C. maculatus is a major pest of stored products in all but one continent and is responsible for considerable economic loss on worldwide. It is also a key model organism in research due to their short generation time, sexual dimorphism, life-history and the ease with which their natural environment can be mimicked in the lab. Both theoretical and applied
studies are harnessing the potential for various biological control agents to be used to examine evolutionary responses to parasitism to ask both fundamental evolutionary questions and assess the long term consequences of biological agents of control on populations over time.
Our initial work has focused on parasitism with a natural parasite of insects, the fungal agent Beauveria sp. and this is also a candidate for biological control. Our data suggests infection reduces longevity but that females may shift resources to early reproduction and increase their egg laying rate. Such fecundity compensation in response to parasitism has been observed in a number of other species but could be an undesirable effect for a pest control strategy. Females may also alter allocation levels to offspring – what consequences would this have for the reproductive potential of surviving sons and daughters. Infected individuals may also decrease levels of competition within a population: what effect might this have on uninfected individuals in a population and overall levels of reproduction in the longer term? This project will investigate the impact of infection on life-history trade-offs, mating behaviour and mating success and the transgenerational consequences of infection for male and female offspring. There is scope for the student to direct the project to look at particular aspects of mating behaviour or life-history they find most of interest and to expand it to consider the effects of infection on interacting non-parasitised members of the population and hence the consequences of parasitism at the population level.

Key research questions
How does infection impact on host traits in different populations in different environments? Which type of traits are most likely to be affected by infection at different life stages? How does infection impact across generations? What are the social consequences of infection and how do effects via non-hosts combine to impact at the population level?

The project will involve designing and implementing controlled experiments to examine the impact of infection and immune challenge on different individuals in a population – both hosts, non-hosts and their family members. Populations can be created that mimic the pests species’ natural environment and conditions can be manipulated to mimic different environmental conditions. There is scope to measure the impact of infection on a range of life history traits at both the individual and population level and to break these down into different components depending on the students area of interest, e.g. egg provisioning, ejaculate components, physiological measures. Multi-generation experiments are easily conducted in the proposed system as is the tracking of individuals or populations over time.
Year 1: Research training, planning of experiments, statistical training, animal husbandry training, lab and culturing techniques, planning and completion of first set of experiments.
Year 2: Completion of second set of experiments, initial conference presentations, analyses and writing. Ongoing professional training.
Year 3: Completion of final set of experiments, analyses and writing. Conference presentation, opportunity for professional placement in non-academic sector.

Requirements: Students need at least an upper 2.1 degree in a related biological subject and a first class undergraduate degree or MSc in ecology or evolution would be an advantage. All training will be provided but any related experience would be an advantage.

For further information please email [Email Address Removed]