Different threshold responses in spontaneously changing postagrogenic forest and unmanaged grassland. Shifts in small mammal populations and communities triggered by an extraordinary drought.

Due to their resilience, various biological systems under environmental changes typically exhibit nonlinear responses with sudden, abrupt shifts. Although such shifts are theoretically expected, few studies traced state-and-transition dynamics in nature (Liu et al., Science 317:1513-1516, 2007).