"The authors empirically demonstrated that the spatial heterogeneity of the physical environment mediates the effects..." Evaluation of: [Griffin J et al. Spatial heterogeneity increases the importance of species richness for an ecosystem process. Oikos. 2009; 118:1335-42; doi: 10.1111/j.1600-0706.2009.17572.x]. Faculty of 1000, 20 Jan 2010. F1000.com/1555978