Grateful for the dead: the widespread importance of dead foundation
species for biodiversity, ecosystem function, and resilience.
AbstractFoundation species such as corals, trees, and bivalves enhance ecosystem
function and biodiversity by creating habitat for associated organisms,
ameliorating stress, and modifying energy flow. However, theory
generally ignores their ecological functions after death. Here we review
the traits and functions of dead foundation species relative to their
living counterparts, and the processes that control their persistence.
We also conduct a meta-analysis to quantify where the effect of dead
foundation species on community functions is unique or redundant to
their living counterparts. We focus on marine ecosystems due to the
greater diversity of foundation species they support and the increasing
prevalence of mass-mortality events in these systems. Our study reveals
how foundation species continue to provide important functions after
death and exhibit new functions that are distinct from when they are
alive. We develop a framework using broad, trait-based functional
differences among types of dead foundation species to predict whether
they will promote stability by enhancing ecosystem resilience or promote
shifts to alternate states. Our synthesis establishes how an
understanding of the ecological importance of dead foundation species
can assist in predicting system trajectories, enhance restoration and
conservation efforts, and contribute to ecological theory on habitat
heterogeneity and ecosystem function.