After years of publications on data and theory, plant and animal biodiversity has been championed as one of the the greatest determinants of ecosystem functioning. However, the nuances of biodiversity descriptors most appropriate to describe a community as well as the applicability of such theories to microbial ecology remain elusive. Traditionally, species richness was the most widely used index to quantify biodiversity by community ecologists, which ignores the ecological similarities and differences among species. Recently, phylogeny- and trait-based metrics are being increasingly applied. These have been used to link diversity patterns to underlying mechanisms operating the community assembly processes and further offer fundamental insights into ecosystem functionality like productivity, resilience and restoration. However, the use of only phylogeny or trait based metrics may not provide sufficient power in comprehensively explaining and predicting the dynamics of ecosystem functioning. Both offer their own set of limitations; for phylogenetic approaches, although they incorporate information on evolutionary history, they may miss species’ ecological niche similarities and differences since traits may be labile and not phylogenetically conserved. For functional trait measures, although they relate to community functions involved in resource use, environmental tolerance, and interspecific interactions, it can omit information on a community’s potential or overlap of niche space, and just quantifies community differences after a process has occurred instead of providing a basis to make robust a priori predictions about community diversity. Therefore, integrating phylogeny and functional traits is a promising way to provide deeper insights into the mechanisms of species coexistence and competitive exclusion, and a great benefit of understanding their contributions to ecosystem function. This oral session will rally plant ecologists, microbiologists, and bioinformaticians with broad backgrounds to focus on several fundamental questions: Do traits and phylogeny tell us the same thing about communities? Are there biogeographic patterns of phylogeny and functional traits across fragmented habitats or large spatial scales? How can assessments of phylogeny and functional traits be combined to reveal the ecological processes involved in primary succession, interspecific interactions and ecosystem stability? How can we build better approaches to predict the dynamics of ecosystem function using phylogenetic and functional information?