Species of the plant family Proteaceae exemplify the evolutionary radiations that have occurred in South Africa's Cape Floristic Region (CFR) over the past 20 million years. Many of the 330 species are found nowhere else in the world. This project explores the relative importance of adaptive and neutral processes in the evolution of the White Proteas, a small endemic group within the genus Protea. Because water and nutrients are likely to limit survival and reproduction in the CFR, patterns of differentiation in traits associated with water and nutrient use will be compared with patterns of variation in neutral genetic markers to determine whether natural selection is responsible for diversification. These patterns will then be related to variations in nutrient and water status of soils in wild populations.
In addition to clarifying the mode of evolution in this group, the data will also be useful to the conservation of these species, which are especially vulnerable to the effects of climate change. These data will help conservation and restoration biologists identify populations that are better adapted to heat and drought. The project also fosters co-operation with SANBI, a South African research institute and will help to train undergraduate students in field and lab work techniques.
