The disturbance event sets in motion a reorganization phase, with some of the younger damaged trees able to resprout, while trees that have been absent from the forest at that spot for decades, but whose seeds have lain dormant in the soil, germinate in response to the altered light and temperature at the surface. The seeds of other tree species that require high light levels, arrive on the wind, or are deposited by birds perching on the woody debris and snags left by the tornado. Understory herbaceous species flourish for a time, reproducing and producing large numbers of propagules. The forest regrows as the light-demanding species give way to dominance by the more shade-tolerant species that will ultimately occupy the overstory. This process of episodic disturbance, reorganization, and regrowth are all part of the same forest system. The system as a whole is resilient, although individual components are killed by the tornado, while others take advantage of the changing conditions produced by the regrowing forest itself. This kind of dynamic is a source of the insights embodied in the ecological resilience concept (Holling and Gunderson 2002).
As a result, the adaptive benefit of resource averaging was no longer available. After that time, the return on the investment in administration, infrastructure, grain distribution, and labor sharing became insufficient to purchase the loyalty of outlying settlements and the system then shifted to a completely different realm of control. In other words, the complex Chacoan civilization collapsed. This example shows both that social-ecological systems can exhibit resilience through adaptive behavior, but that it is possible for the interaction of external events and the structure of the system to cause a collapse into a different regimen of control.