Modelling and data analysis of a spatial ecosystem. Ref 52736-014.

A 2 year PDRA is available in the Mathematics Institute analysing interactions in a bacteria-amoeba (spatial) ecology. Mathematical models will be used, parametrissed from individual based data to extrapolate and compare to population behaviour.

The PDRA will work with an experimental group analysing spatial data, videos of interactions and facs data (eg size distributions), in a variety of environments (agar plate, liquid culture, soil) monitored at a variety of spatial and time scales. Behaviours of a number of bacterial mutants will be compared to understand the role of specific bacterial characteristics on the ecology. Fundamental questions include the nature of the interaction, phenotype switching (eg filamentous:non-filamentous shift), spatial dispersion, grazing rates and grazing pressure, and nutrient dependence.

Project details:

Microbial systems offer an opportunity to study ecological population dynamics from the perspective of individual behaviour; their fast time scales (relative to other ecological systems) and the ease of system manipulation mean that the interactions can be decoupled and system processes quantified/parametrised. Using a model 2D agar system an amoeba-bacteria ecology can be monitored at a variety of spatial and temporal scales to give a thorough parametrisation of individual and population behaviour. The project will utilise a large variety of methods (experience in any would be an advantage) including data and image analysis, statistical parameter estimation, dynamical systems analysis , spatial models, structured system analysis, and generation of population models from individual processes. At the simplist level the system is a predator-prey interaction (amoeba the predator, bacteria the prey) and basic wave behaviour is observed in the model system. However additional processes are of varying importance including saprophytic growth, bacterial survival of digestion, bacterial phenotype switch to a grazing resistant filamentous form, amoeba encystment, and amoebal behavioural changes depending on environment, eg speed reduction on detection of bacterial colonies. Two other systems will also be analysed, a liquid culture and a soil microcosm allowing an assessment of the changes of ecosystem behaviour with environment and extrapolation to more realistic ecosystems. Dynamics will be compared for a variety of bacterial mutants and between different environments to determine key determinants of the dynamics.

The project is multidisciplinary with extensive interactions with the Warwick microbiology group. We envisage extensive development of the experimental system as the analysis proceeds. The PDRA will be based in the Mathematics Institute within a group consisting of 4 permanent members of staff and 6+ postdocs (see http://www.maths.warwick.ac.uk/~njb/group.html). The position may be attractive to a mathematical ecologist, statistician or mathematician/physicist interested in mathematical ecology, although preference will be given to candidates with strengths in statistical analysis of data.

To apply:

Candidates should have experience in one or more of the following: spatial ecological models, stochastic/deterministic modelling, data analysis (eg MCMC, maximum likelihood, hypothesis testing, model discrimination), structured models, or more generally experience in linking ecological data to models. The project will involve programming for simulations and data analysis (C/C++, Matlab for image analysis). Applicants should have a PhD in a relevant subject.

Enquiries welcome: Dr Nigel Burroughs, njb@maths.warwick.ac.uk tel (+44) (0)2476 524682. Also see http://www.maths.warwick.ac.uk/~njb.

The appointment is on the RA1A scale. Applications should be made to the Personnel Office, University of Warwick, Coventry CV4 7AL quoting the reference number and include the following: 1) completed application form, 2) full academic CV and 3) application letter outlining relevant experience and skills relevant to the post, and other academic interests. Closing date February 23rd. Starting date Apr-Oct 04 flexible.

The appointment is funded by BBSRC/EPSRC on the RA1A scale £ 17,626 - £26,491 pa.