“…For this, we start from a set of principles that can be summarized as follows: (1) complexity is not an exclusive property of particular human societies (i.e., those having large and dense populations, horizontal or vertical hierarchical organization, deep institutionalized inequalities in terms of access to resources and power, multiple social and economic roles implying specialization and division of labor, large stable settlements, etc. ; Barton 2014;Callhoun 2002;Dallos 2013;Darvill 2008), but a quality of all animal societies because all of them are examples of natural (as opposed to artificial) complex adaptive systems or CAS 1 (in the sense of Gell-Mann 1994, 17) (e.g., Barrientos 2004;Barton 2014;Bernabeu Aubán et al 2013;Bonabeau 1998;Eidelson 1997;Ullah et al 2015); (2) complexity is a composite and decomposable phenomenon that varies across different dimensions and scales (Heylighen 1999;McShea 1996aMcShea , b, 1997Simon 1962) ; (3) complexity is not a threshold characteristic, but a scalar one (Fitzhugh 2003;Kohring 2011) susceptible of being measured on a more or less continuous way (Heylighen 1999;McShea 1991McShea , 1996aMcShea , 1997; (4) there is not a single form of system complexity but multiple variants or types, differentiated according to well-specified parameters (McShea 1996a(McShea , b, 1997; (5) each system, defined on a specific scale, can be-with respect to any other system-more complex in one or more dimensions and less complex in other(s) (McShea 1996a(McShea , b, 1997; (6) there is no "naturally" privileged dimension in or scale at which the complexity of a system can be assessed (McShea 1996a).…”