Phone: 021 650 2444 
Room No.: 3.20 (HW Pearson Building)



Long ago…

As an honours and masters student I worked in the Photosynthetic Nitrogen Metabolism Research Unit at the University of the Witwatersrand, headed by Christopher Cresswell. I saw myself as a whole-plant plant physiologist with a strong interest in biochemistry. My PhD at UCT under the supervision of Owen Lewis continued that interest through exploring the energetic costs of the metabolism of different forms of N. My post-doc at the University of Ben Gurion in Israel, supervised by Herman Lips, also continued that interest, although I started to explore the carbon metabolism of plant roots more extensively. On taking up a post at Stellenbosch in 1995, I continued with this work while diversifying into studying salinity stress and aluminum toxicity. I also became interested in sugar accumulation in sugarcane and worked with Derek Watt and Alistair McCormick at the South African Sugar Research Institute (Durban) on understanding how sucrose accumulation elicits feedback control of photosynthesis. I also started working on the nutrition of indigenous species, particularly Proteaceae, and the fascinating roots that enable them to acquire phosphate. This led to collaboration with Hans Lambers at the University of Western Australia. When I moved to UCT in 2004 I considered myself a physiologist, with some interests in ecophysiology (e.g. of alien invasives). At UCT, however, I was however plunged into a world of ecology; an area of study in biology that I had previously thought somewhat dull! To my surprise, I found lots of interest in the field and was able to apply some physiology/ecophysiology to ecological problems.

More recently…

It amuses me that some of my colleagues now think of me as an ecologist, despite one of my former colleagues (not James Bond) having assured me some years ago that I would never “make it as an ecologist”. While that might be true, I am now working on quite a mixed-bag of mostly ecological topics.  I am fascinated by spatial patterns in ecosystems (e.g. fairy circles, heuweltjies, savanna trees, vegetation boundaries and occasionally termites). For example, I have worked with William Bond and Simon Power on vegetation boundaries in the Cape Floristic Region and elsewhere in South Africa. In this I am interested in how plant physiology contributes to these vegetation patterns. I am also working with Jeremy Midgley and Jo von Holdt on heuweltjies and fairy circles; both, we argue, the consequence of ecological vegetation patterning. Thanks to collaboration with Tony Verboom, I have developed a strong interest in spatial variation in species richness of plants. We have been exploring the drivers of the remarkable species richness of the Cape in the context of global richness. I also work extensively with Heidi-Jayne Hawkins and have participated in some of her savanna research projects. A fun project with Heidi was the PhD of Zander Venter that re-examined the claims of Holistic Planned Grazing, and found no support for many of those claims. With Brad Ripley (Rhodes) and Michele Greve (Pretoria) we have been working on the ecology of the sub-Antarctic Marion island and the role of climate change in driving vegetation shifts.

A semblance of a theme

One of my focusses in all aspects of this research has been the role of nutrients in plants and also in ecology. One of my key interests is in the interaction between water and nutrients. I hold the somewhat radical view that water flux through plants is mostly a solution to the need for the acquisition and movement of nutrients, i.e. not an “unavoidable evil” as it is sometimes considered.

Uncertain times

What I love about science is being able to question the received wisdom and finding new angles on old problems. As I get older I am acutely aware of the dreaded “infallibility syndrome” (Weinberg F. 1992 Phys. World 5, 76) that seems to afflict some older academics. As a symptom of my fallibility, however, I am now enjoying embarking on a mission to reinstate an idea of mine that I helped debunk. I argue that this is just science in action. Also, I am very uncertain about quantum mechanics.



Apart from post-graduate supervision, I participate in Bio20017S (Plant diversity and functional biology), Bio3013F (Global change ecology), Bio3018F (Ecology and evolution, which I coordinate) and Bio3019S (Quantitative biology).