Abstract
The Tree of Life—phylogeny—provides a powerful tool for understanding the processes regulating life’s diversity. Conserving the branches on the Tree of Life might also have practical benefits. Using a comprehensive phylogeny of south ern African woody trees and shrubs, and structural equation modeling, we show that human population density correlates closely with not only the richness of woody plants in a region but also their evolutionary relatedness. Further, we demonstrate that more phylogenetically diverse species assemblages support a greater diversity of ecosystem goods and services. Our results suggest that peo ple in Africa may gain material benefits from inhabiting regions that support high phylogenetic diversity of woody plants. However, the correlation between human population and woody plant diversity creates a tension between people and biodiversity, which could threaten the contributions to people provided by intact and phylogenetically diverse ecosystems.
This research was supported by the Government of Canada through Genome Canada and the Ontario Genomics Institute (2008-OGI-ICI-03), the University of Johannes burg, the South African National Research Foundation, the Royal Society (UK), and the Toyota South Africa through the Toyota Enviro Outreach Programme. KY was additionally supported by NRF grant #112113.