Niche vs neutral and top-down vs bottom up: Bridging the gaps between theories of community assembly

Background/Question/Methods

We present a new theoretical framework for community assembly, placing species interactions at the forefront. Our approach provides an alternative way to bridge the gap between niche and neutral theories, maintaining some of the analytical tractability of neutral theory, while introducing the species and resource interdependencies characteristic of niche theory. We extend the framework across multiple trophic levels, and examine how food web structure and dynamics can be related to the distribution of abundances within a community.

Results/Conclusions

We develop a suite of predictions using the simplest possible null model within our framework. These predictions allow us to relate multiple ecological metrics, including the species abundance distribution, the species-individual relationship and the link-species scaling law in food web theory. We then discuss deviations from this null model, and whether the relationships between our predictions are robust to these generalizations.