Biological invasions, species distributions, community ecology and ecosystem processes
The research of the group can be classified into four broadly overlapping areas:
Biological invasionsresearch includes studies on the impact of invasive species, quantifying invasion debt and pathways of introduction. In a recent study we investigated shipping as a pathway of introduction by analyzing ship movements and quantifying environmental similarity between ports to identify high risk routes. We have recently done some studies on the pet trade in South Africa as a potential introduction pathway for alien species.
Species distribution modelling can be used to identify geographic areas that are environmentally suitable for a species. We have used species distribution models to determine the likelihood that invasive species that have not yet been introduced in to South Africa (e.g. Emerald Ash Borer) could survive, or how invasive species within South Africa are likely to spread e.g. (Pompom weed, Tree of Heaven and fruit flies).
Community ecology research includes quantifying patterns and drivers of diversity across elevation gradients. To date, much of this research is focused on investigating ant taxonomic and functional diversity across elevation. Elevation gradient studies enable us to understand the influence of climate (temperature in particular) on ant communities. Most of this work has taken place as part of the Sani Pass Elevation Gradient project.
Ecosystem processes research includes studies to understand the role of insects (such as termites and ants) on ecosystem processes such as nutrient transport, decomposition and bioturbation (soil movement). A recent study investigated the impact of bush encroachment (woody thickening) on grass decomposition in savanna. Termites play a major role in decomposition and bush encroachment can negatively influence their ability to perform this important function. A current research project is investigating the role of animals in soil ecology, with a particular focus on termites and ants in savanna. We are investigating this by means of suppression experiments.