lundi 4 janvier 2016
Funded PhD position at University of York
NERC Doctoral Training Partnership
ACCE: Adapting to the Challenges of a Changing Environment
Trans-generational effects of environmental stressors in fish
Supervisors: Kathryn Arnold & Karen Thorpe (University of York), Lynne Sneddon (University of Liverpool) & Gloria Pereira (CEH, Lancaster)
Experiencing the appropriate conditions for the growth and development of the offspring is an important aspect of an individual’s success. Numerous examples illustrate the extent to which the same genotype can produce very different phenotypes depending on the early developmental conditions. One of the most interesting recent conundrums posed is the extent to which environmentally-induced phenotypic change is adaptive. Sometimes this may be clear, if it maximizes immediate survival of young. In other cases, further proof of the adaptive significance is required. Consequently, we need to establish how environmentally-induced phenotype changes occur and their impacts on fitness.
Understanding the interplay between rearing environment and fitness is of applied relevance in the face of rapid human-mediated environmental change. Aquatic organisms are exposed to many anthropogenic challenges during development, including changes in food availability, temperature and chemical contaminants, including pharmaceuticals. Unmetabolised drugs, including antidepressants, have been shown to be excreted into sewage and end up being discharged unchanged into rivers and streams. Many studies have demonstrated effects on the behaviour, physiology and reproductive traits of fish exposed to antidepressants. However, the capacity of antidepressants in the environment to affect the phenotype of offspring and grand-offspring, i.e. to have trans-generational effects, remains to be tested.
This studentship will investigate how exposure of parents to relatively low concentrations of a chemical contaminant, the antidepressant fluoxetine (also known as Prozac), affects the phenotype of future generations. To date it has been assumed that the changes in behaviour and physiology observed in response to low doses of fluoxetine are maladaptive, but this remains to be tested.
In aquaria, parental fish will be experimentally exposed to environmentally relevant concentrations of fluoxetine. This antidepressant modulates biochemical changes in the brain associated with anxiety and stress, but can also affect appetite and activity levels. Using a standard breeding design the student will investigate whether, compared with controls, offspring and grand-offspring of parents exposed to fluoxetine:
1) Experience changes to survival, physiology and behaviour;
2) Show different patterns of neuronal activity in the brain correlated with important behaviours such as prey capture and predator avoidance.
3) Perform differently when exposed to stressors such as fluoxetine, predator risk and food shortages.
Experimental data on the transgenerational effects of fluoxetine will then be analysed within an evolutionary framework. Our model-fish system can then be used to make predictions concerning the long term impacts of pharmaceuticals in the environment. This studentship will suit someone wishing to gain experience in applied aquatic ecology, ecotoxicology and/or behavioural ecology.
Email Kathryn.Arnold@york.ac.uk for more information or to make informal enquiries.
For how to apply see: http://www.york.ac.uk/environment/postgraduate/nercdtp/
Deadline 11th January 2016
Dr Kathryn Arnold,
University of York,
York YO10 5DD, UK
Tel: (44) 01904 322997
Catégories PhD à l'étranger