Print PageIt has been recently hypothesized that evolutionary history should influence the Biodiversity Ecosystem Functioning (BEF) relationship. This important new direction in the BEF literature is however based on few empirical investigations. Here we combine experimental evolution and ecological experiments with bacteria to show how evolutionary constraints impact the BEF relationship. In a first experiment we isolated 20 bacterial strains from a marine environment and evolved each to be generalists or specialists. We then constructed assemblages of 1 to 20 species from each lineage. In a second experiment we varied phylogenetic and species diversity independently to determine the relative contribution of phylogenetic and species diversity to the BEF.
Results/Conclusions
In the first experiment, we found that assemblages of generalists were more productive on average because of their superior ability to exploit the environmental heterogeneity. The slope of the BEF relationship was however stronger for the specialist assemblages because of enhanced niche complementarity. In the second experiment we found a positive relationship between phylogenetic diversity and productivity only for ancestor. We found that the observed relationship between phylogenetic diversity and ecosystem functioning can rapidly be broken down in the presence of directional selection. Our results show how the BEF relationship depends critically on the legacy of past evolutionary events and have immediate implications for future conservation strategies.
