Community reassembly is an important concept in community ecology, but in most circumstances cannot be observed and is hypothetical. Reassembly of communities is an observable process that can be examined effectively following species invasions. Our study system in southeastern Arizona has declined in diversity and abundance of native winter annual plants coincident with a sustained irruption of a nonnative invasive Eurasian s...

Dispersal is a major and critical process in population biology that has been particularly challenging to study. Animals can have major roles in seed dispersal even in species that do not appear specifically adapted to animal‐aided dispersal. This can occur by two processes: direct movement of diaspores by animals and modification of landscape characteristics by animals in ways that greatly influence dispersal. We exploited th...

We investigate the effect of seed predation on the coexistence of competing annual plants. We demonstrate a role for predation that is opposite to the conventional wisdom that predation promotes coexistence by reducing the intensity of competition. In the common situation where competitive coexistence involves intraspecific competition exceeding interspecific competition, predation can undermine coexistence by reducing the ove...

In the presence of permanent spatial heterogeneity, local dispersal, especially short‐range dispersal, can facilitate coexistence by concentrating low‐density species in the areas where their rates of increase are higher. We present a framework for predicting the effects of local dispersal on coexistence for arbitrary forms of dispersal and arbitrary spatial patterns of environmental variation. Using the lottery model as an ex...

We use a meta‐analysis of density dependence in reef fishes to evaluate how ecologists approach detection, inference, and estimation. We compared two groups of studies: those that detected effects of density on survival and those that did not. Distinctions between these groups have spawned heated debate about the processes that affect fish dynamics. Per capita effects of density were similar between the two groups, although to...

This review discusses the interface between two of the most important types of interactions between species, interspecific competition and predation. Predation has been claimed to increase, decrease, or have little effect on, the strength, impact or importance of interspecific competition. There is confusion about both the meaning of these terms and the likelihood of, and conditions required for, each of these outcomes. In thi...