Data and code for "Dynamic changes in community composition and rank abundance distributions revealed with a demographic neutral model"

How do assemblages change through time? Ecologically realistic models aimed at answering this question need to account for the underlying population dynamics of the constituent species and to predict different facets of biodiversity change. Here we introduce a new neutral model (TDM, the Taylor Dynamic Model), in which the abundance of each species fluctuates independently through time in a random walk informed by Taylor’s power law. Using simulated and empirical data, we show that TDM predicts key patterns of ecological assemblages including non-equilibrium assembly structures, species accumulation, extinction and rarity rates, resource use, and compositional change. In a case study involving marine taxa, TDM detected long-term changes in species richness, composition, and rank order with an excess of recently decreasing species. TDM thus uncovers non-random temporal trends in alpha and beta diversity and identifies systematic shifts in abundance that may be signatures of community reorganization associated with environmental change.