Population dynamics and complex changes in the environment: what can we predict?

Dr Dylan Z Childs; Dr Philip H Warren                                                                                                                  Key Words: population, environmental change, ecotoxicology, conservation, microcosm, modelling

The impact of a shifting environment can be complex, yet understanding and predicting the effects of environmental change is critical if we are to successfully manage the effects of anthropogenic processes. For example, a change in the external environment can directly alter organisms’ performance (e.g. warming may increase metabolic rates), though it may simultaneously act indirectly through an effect on interacting species (e.g. warming may simultaneously increase a competitor’s performance). The relative importance of these ‘direct’ and ‘indirect’ drivers of ecological change may also vary with the environment. Finally, a shift in the environment frequently involves multiple axes (e.g. changes in temperature, pH, and productivity are expected in marine systems subject to climate change).

This project aims to develop new approaches for quantifying changes in the relative importance of direct and indirect processes under a diverse range of environmental conditions. We will use experimental microbial microcosms, state-of-the-art statistical tools, and simple mathematical tools. Our aim is to understand how different types of environmental change interact to shape the ecological dynamics of a focal species. Key questions to be resolved include: 1) Do different methods for quantifying direct and indirect effects lead to similar conclusions? 2) Can we predict the combined impact of environmental perturbations from their effect in isolation, or is this likely to be ‘more than the sum of its parts’? 3) Are the conclusions from 1 and 2 broadly preserved in the presence of different types of ecological interaction with non-focal the species (e.g. competitors vs. predators)?

The student will receive training in mathematical population biology, computational ecology, and experimental microbial ecology. The project would suit a biosciences graduate with a strong interest in multidisciplinary approaches to ecology; or a physical sciences, engineering or mathematics graduate keen to make the transition to ecology. The student will have the opportunity to visit our collaborator (Prof Owen Petchey) at the University of Zurich, Switzerland.

For more information about how to apply, or the application process, please contact Mrs S Carter (s.a.carter@sheffield.ac.uk).

To apply now go to: http://www.sheffield.ac.uk/postgraduate/online