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
This project will test whether multiple environmental cues are used in concert to facilitate adaptive plasticity in investment in survival and reproduction.
Organisms must adjust investment into survival and reproduction to match a variable environment. One mechanism for this is phenotypic plasticity; the ability of a single individual to express different phenotypes under different environmental conditions. A well studied example of phenotypic plasticity is increased lifespan and reduced reproduction in response to low food availability. Known as the DR response, research to date has focussed on mechanism, with the so called ‘nutrient sensing’ pathways heavily implicated. However, the evolutionary explanation (i.e. why this response exists) has received much less attention. Recently, we have suggested that the DR response and nutrient sensing pathways are part of a broader suit of responses that have evolved to enable organisms to respond adaptively to a range of environmental variables including photoperiod, temperature and nutrition. This PhD will use Drosophila melanogaster to test the predictions of this theory.
Do multiple environmental cues (e.g. temperature, photoperiod, nutrition) have different effects on life history traits than single cues?
Do predictive environmental cues alter resistance to environmental insults or stress?
Is there a cost to this phenotypic plasticity?
Do nutrient sensing pathways have a role in plasticity to non-nutritional environmental variation?
Are flies from variable environments more plastic?
The student will use controlled experimental manipulations to test the role of multiple environmental cues in determining survival and reproduction. Experiments will focus on characterising the response to well known cues including temperature, photoperiod and nutrition. Photoperiod and temperature can be easily manipulated using timed lights and incubators and our lab is well versed in creating diets. Environmental stressors such as cold stress and starvation are easy to apply to Drosophila. The nutrient sensing pathways are well characterised in Drosophila and a number of knock-outs exist to test the role of these pathways in sensing cues other than nutrition. It is also possible to collect Drosophila in the field from more or less seasonal environments to investigate natural variation in plasticity and nutrient sensing pathways.
In year 1 the student will carry out experiments to investigate questions 1 and 2. In year 2 the student will move on to the more involved experiments required for questions 3 and 4 and will investigate the possibility of collecting flies from different environments. Year 3 is more open for the students own interests, but could involve investigating the degree of plasticity and the responsiveness of nutrient signalling pathways in flies from more or less variable environments.
A comprehensive training programme will be provided comprising both specialist scientific training and generic transferable and professional skills. Specialist training will include Drosophila husbandry and experimental manipulation, assaying components of the nutrient sensing pathway and the use of complex multivariate statistics including mixed effects models.
A first class undergraduate degree or MSc in ecology, evolution or a related subject is desirable
A keen interest in the evolution of plasticity and its underlying mechanisms
Experience with Drosophila and/or nutrient sensing pathways would be an advantage