Developmental change in predators drives different community configurations

Theoreticians who first observed alternative stable states in simple
ecological models warned of grave implications for unexpected and
irreversible collapses of natural systems (i.e., regime shifts). Recent
ecosystem-level shifts engendering considerable economic losses have
validated this concern, positioning bistability at the vanguard of coupled
human-environment systems management. While the perturbations that induce
regime shifts are known, the ecological forces that uphold alternative
stable states are often unresolved or complex and system-specific. Thus,
the search continues for general mechanisms that can produce alternative
stable states under realistic conditions. Integrating model predictions
with long-term zooplankton community experiments, we show that the core
feature of ontogenetic development, food-dependent maturation, enables a
single community to reach different configurations within the same
constant environment. In one configuration, predators regulate prey to
foster coexistence, while in the other, prey counterintuitively exclude
their predator via maturation-limiting competition. The concordance of
these findings with the unique outcome and underlying mechanism of a
general model provides empirical evidence that developmental change, a
fundamental property of life, can support bistability of natural systems.