Constraint For non-nested hierarchies, frequency and constraint are most important characteristics Constraint'can be a 'passive condition tree canopy provides shade and therefore constrains seedling regeneration Constraint allows ecological systems to be predictable the level in question is constrained by an envelope of permissible behaviours Name of the game"in landscape ecology(or science generally) is to find constraints that enable(spatial) prediction4. Constraint - For non-nested hierarchies, frequency and constraint are most important characteristics - ‘Constraint’ can be a ‘passive condition’ : tree canopy provides shade and therefore constrains seedling regeneration - Constraint allows ecological systems to be predictable : the level in question is constrained by an envelope of permissible behaviours - “Name of the game” in landscape ecology (or science generally) is to find constraints that enable (spatial) prediction