Department of Botany and Zoology

The Department teaches and conducts research at postgraduate level in a variety of internationally competitive research programmes. It is a leader in the field of evolutionary biology, with a specific focus on the unique opportunities offered by Africa's biodiversity.

It is also home to the DST/NRF Centre of Excellence for Invasion Biology (CIB). The CIB aims to improve the ability, through scientific knowledge, to understand, control and manage invasive species to improve the quality of life of all South Africans.

Fields of research

Animal evolutionary ecology and physiology: This is focused on whole-organism performance and how it is influenced by changes in the environment. It involves three main topics:

traits that are essential for organism functioning;
the environment that is perceived by the organism and how much the environment varies; and
the strategies or adaptations that organisms use to cope with variable or sub-optimal environments encompassing behavior, flexible physiological responses and evolution.

Evolutionary ecology: This research uses an integrative approach, spanning molecular to community level perspectives, to address two broad themes:

the evolution and ecology of interactions between plants and their symbionts; and
the diversification of the Cape biota and its consequences for coexistence.

Specific topics include evolution of specialisation, floral diversification, plant breeding systems, community assembly, coevolution, plant-insect diversity relationships, insect/bird behaviour, seed dispersal, speciation, hybridisation, polyploidy, plant-insect-fungus-bacteria interactions, plant growth form diversity, plant systematics and taxonomy.

Animal plant interactions: This research covers a variety of topics and uses an integrative approach to study floral diversification, plant-insect interactions, plant-insect diversity relationships, insect behaviour and how it relates to floral evolution, colour of flowers, dispersal evolution, the origin and maintenance of species, the coexistence of species and the diversification of the Cape flora and fauna.

Behavioural ecology: Here the focus is mainly on animal communication, in particular the evolution of animal signals, whether they are olfactory, acoustic or visual. One aspect of the research is the analysis and identification of the signalling systems used by social insects in maintaining colony co-ordination and functioning which is integral to untangling the evolution of sociality in the animal kingdom. Another focus is on various communication strategies used by birds and mammals in relation to mimicry, mate choice, mate guarding, territoriality and helping behaviour.

Cape flora research group: This research focus mainly on DNA based phylogenetic reconstruction and the general biology of the organism (e.g., morphology, palynology, karyology and breeding systems) to reconstruct the evolution of a number of Cape lineages. It is focused on the evolution of alternative growth forms, the evolution and breakdown of the tristylous breeding system, the evolution of recalcitrance and varied seedling recruitment strategies, the role of hybridization in driving the observed diversity and the mutualistic interactions between Fynbos plants, ophiostomatoid fungi and insects.

Invasion Biology: Members undertake research on the biodiversity consequences of biological invasions. The principal aims of the Centre's work are to reduce the rates and impacts of biological invasions by furthering scientific understanding and predictive capability, and by developing research capacity.

Ecophysiology: The current and prospective research activities of this group fall in two basic fields of interest. First herpetology and environmental health (endocrine disruption) that enable us to conduct basic descriptive research and to test hypotheses associated with our research programme. Secondly we have a strong focus on applied issues like EDCs in the aquatic environment. Most of our current projects include fish, amphibians and reptiles as model systems.

Evolutionary genomics: Members of the Evolutionary Genomics Group combine diverse expertise in molecular analyses to study the evolutionary history of terrestrial and marine fauna and flora. The research is not taxon-specific and is aimed at strengthening conceptual, experimental, analytical and computational expertise in molecular ecology, conservation genetics, comparative cytogenetics, population genetics, phylogeography, comparative genomics and molecular phylogenetics.

Marine research: The research group has four main focal areas, namely polychete biogeoraphy and reproduction, marine invasion ecology, molecular marine ecology and sustainable mollusc culture. This group utilises modern research techniques to better understand southern Africa's dynamic marine realm. Research projects are diverse and range from applying genetics in Marine Protected Areas to assessing impacts of marine alien species.

Nutritional plant physiology: This research focuses on the molecular plant physiology of phosphorus nutrition during plant-microbe interactions. Their work is directed at the phosphorus nutrition of legumes in symbiosis with mycorrhizas and nitrogen fixing bacteria. This entails the integration of classical plant physiological methods with modern tools such as transcriptomics and proteomics. Various legumes are being used in specific projects, which include model legumes (Medicago truncatula, Lupinus spp; Phaseolus vulgaris) indigenous legumes (Virgilia spp, Aspalathus spp, Cyclopia spp) and invasive legumes (Acasia spp).

Vertebrate functional biology and herpetology: The Vertebrate Functional Biology Group aims at generating baseline biological data on the lower vertebrates of southern Africa by studying:

fire ecology of lower vertebrates,
physiological biomarkers as indicators of environmental change,
energetics and thermoregulation, lizards as sentinals for Global Climatic Change,
reproduction biology of southern African reptiles, and
evolutionary biology of cordylid lizards.

Global change ecology: The focus is primarily on climate change and related impacts on unique and often high-biodiversity southern African terrestrial ecosystems, including sub-Antarctic islands. Experimental eco-physiological and systems ecological approaches are applied to develop the mechanistic understanding behind biodiversity responses to climate change trends and to other global change drivers, and the ecosystem structural and functional impacts. This understanding is combined with bioclimatic niche-based modelling (NBM) approaches, hybrid NBM/demographic approaches, and dynamic global vegetation modelling (DGVM) approaches in collaboration with leading groups globally. Predictive application covers a wide range of spatial scales from sub-landscape to continental. The work is cognisant of potential policy value and biodiversity and ecosystem management implications.

Medicinal plant biotechnology: This group focuses on the use of plants for medicinal purposes by local people. The aim is to gain a better understanding of the influences of the environment on medicinal plants and associated secondary metabolites specifically in the regulatory mechanisms involved in secondary metabolite production. Biotechnology is applied to a conservation and commercialization strategy. The group largely focuses on medicinal plants that are important in the Greater Cape region.

Plant molecular ecology: This research is mainly focussed around the evolutionary biology and molecular ecology of both native and invasive plant species. The main focus areas of the research include:

understanding the demographic processes underlying invasive plant populations;
the historical biogeography of native plant populations and the processes that shaped them;
landscape genetics of invasive plant populations; and
the effects of extreme long-distance dispersal in explaining historically-disjunct plant species distributions.