Inverse priority effects: A role for historical contingency during species losses

Communities worldwide are losing multiple species at an unprecedented
rate, but how communities reassemble after these losses is often an open
question. It is well established that the order and timing of species
arrival during community assembly shapes forthcoming community composition
and function. Yet, whether the order and timing of species losses can lead
to divergent community trajectories remains largely unexplored. Here, we
propose a novel framework that sets testable hypotheses on the effects of
the order of species losses inverse priority effects and suggests its
integration into the study of community assembly. We propose that the
order of species losses within a community can generate alternative
reassembly trajectories, and suggest mechanisms that may underlie these
inverse priority effects. To formalize these concepts quantitatively, we
used a three-species Lotka-Volterra competition model, enabling to
investigate conditions in which the order of species losses can lead to
divergent reassembly trajectories. The inverse priority effects framework
proposed here promotes the systematic study of the dynamics of species
losses from ecological communities, ultimately aimed to better understand
community reassembly and guide management decisions in light of rapid
global change.