Lay summary
BackgroundThe species environmental niche consists of the biotic and abiotic conditions necessary for long-term persistence. This concept occupies a central place in the ecological theories of competition, limiting ecological similarity, and species distribution. The niche is also important in determining how species respond to ongoing climate change. Species with narrow niches occur in the few geographic locations that offer acceptable conditions. When these species have limited capacity for dispersal, and/or have been isolated by human activity, climate change may force upon species the alternatives of rapid adaptation (via response to natural selection) or extinction. We focus on the niches of species in the Restionaceae, largely endemic to South Africa.The GoalsWe seek to understand how the species niche has evolved and how the capacity for niche change might impact future patterns of species diversity in the face of ongoing climate change. Gaining an understanding of these niche dynamics entails understanding how species niches differ currently and how these differences evolved. We need to understand how rates of evolution in groups of related species change in time. To understand how niche evolution translates into changes in biodiversity, we need to understand how ecological similarities among species, represented by species evolutionary relationships, influence the composition of ecological communities.The ApproachWe combine the approaches of evolutionary theory, molecular systematics, and ecology. The approach is interdisciplinary in that activities in these areas produce results that are used to support subsequent activities in other disciplines. Notably, DNA sequence data provide the raw material for developing hypotheses of evolutionary relationships. Data on species occurrences and climate allow us to model the species niche. We combine information on evolutionary relationships, ecological characteristics, and species composition in communities to determine how evolutionary relationships influence the assembly of communities.The Significance of the ProjectThis project develops a framework for evaluating how rapid evolution might contribute to species responses to climate change. With this framework it will be possible to evaluate the potential for evolutionary response to climate change in large groups, potentially hundreds, of related species. We will develop more informed projections of the impacts of ongoing climate change by combining ecological data, understanding of evolutionary relationships and rates, and projections of future climates.