Bridging Theory and Experiments of Priority Effects

Although priority effects play a key role in structuring natural communities, considerable confusion and uncertainty remain about when and how they affect different ecological systems. Reviewing previous empirical studies, we show that most of the confusion arises because the term priority effect is often used indiscriminately without considering the various underlying mechanisms or the temporal scales at which they operate. Traditional theory has focused on a single mechanism that applies to a subset of natural systems, revealing a troublesome disconnect between theory and experiments. We propose a new framework that categorizes the different mechanisms of priority effects into two functional groups. We show how this unifying framework allows ecologists to predict the consequences of priority effects across diverse natural systems.