Gareth Witten

I am currently doing a PhD in applied mathematics at the University of Cape Town, South Africa. My undergraduate studies were in biochemistry and applied mathematics and I continued with an honours degree in biomedical engineering at the medical school, University of Cape Town. After lecturing mathematics for two years in the engineering faculty, I was awarded a graduate fellowship to Wesleyan University in Connecticut, USA, to do PhD coursework (dynamical systems) and then returned to the Department of Mathematics and Applied Mathematics, University of Cape Town, to take an Junior Lecturer post.

My current research is concerned with predicting the products of digestion and consequently the partitioning of energy in metabolism. This involves modelling the processes involved in the rumen of ruminants, which includes developing models of microbial competition and the spatial heterogeneity of nitrogen sources and its effects on microbial dynamics and ultimately on rumen function. Included in this model is a sub-model of nitrogen diffusion across the rumen wall, which plays a vital role in animal adaptation on arid and semi-arid rangelands.

I am also fascinated by questions of how physiological and metabolic systems are controlled. This fascination has led to the development of a model of how energy partitioning between fat and protein is controlled in ruminants and humans. Recent research also involves attempting to understand spatio-temporal dynamics of the components of arid and semi-arid rangeland and to understand how plant species richness, ecological resilience and scale are related.

I am very thankful for this opportunity to contribute towards the Santa Fe Institute’s mission to build a community of excellence and to promote an interdisciplinary approach to science. I look forward to actively participating in the many activities at the Institute.