Fig. 2. A) A generalized model of threshold interactions showing all possible combinations of domains and scales and the possible interactions between regime shifts at various domain-scale combinations. B) The critical combinations of domains, scales, and interactions across the four examples. Solid lines indicate interactions, e.g., regime shifts at one scale combination triggering regime shifts at another, that occured in all four case studies. Dotted lines indicate interactions that occur in only one or two of the case studies.