David Murrell DPhil

d.murrell@ucl.ac.uk
Telephone: (+44)-(0)20-7679-27427
Fax: (+44)-(0)20-7679-5052

My research concentrates on understanding what biological processes act to maintain biodiversity. In other words, what acts as the glue to hold natural communities together? In particular I am interested in the effects of spatial structure on population and community ecological and evolutionary dynamics.

In 2006 I was awarded a Natural Environment Research Council Blue Skies Fellowship to investigate the maintenance of biodiversity in plant communities and in particular tropical rain forests. Spatial structure is particularly important in plant communities because, as has often been observed, plants stand still and interact with their neighbours. This might seem almost trivial but for most of its history ecology has not considered spatial structure in its formal theory. My work incorporates local interactions and local movement/dispersal using a method called moment closure. Moment closure was first developed in physics and is often used to model turbulence but it turns out that it is useful in the analysis of models that previously could only be done by computer simulation.

The theoretical framework for plant ecology is arguably still someway behind that for animal ecology. Whilst neighbourhood interactions have been incorporated into models, incredibly size structure has yet to be added. This is despite strong evidence that shows neighbour size may be at least as important as neighbour identity. (A good big `un will almost always beat a good little `un.)
Key areas of future research

1. My previous work has shown that the distances over which interactions occur are crucial in deciding the outcome of competition. Yet, we still know very little about the distances over which plants interact. One of my aims is to gain a better understanding of the spatial scale of neighbourhood interactions.

2. I will develop theory so that it is more relevant to natural communities. One goal is to develop models that incorporate both neighbourhood interactions and size structure. Such a model will be highly non-linear and this means that it is hard to predict a priori the effects of adding in size structure. But this also makes it more interesting.

3. I also want to test more spatial theory via experiment and manipulation of natural communities. There is still a vast body of spatial theory that has yet to be tested.

4. There exists a gulf between theory and empirical research in spatial ecology. Theory almost always talks about long term dynamics, whereas empirical research is often over short time scales. Can the two be successfully reconciled?

PhD Studentships:

From time to time I may have PhD studentships available. However, I am always interested in PhD candidates if they can secure some funding from their home country (if not from the UK). Please email me if you are interested.