A Basic Demographic Unit [and Comments and Reply]

In common with other patrilineal band societies, the Australian dialectical tribe is a nonpolitical product of the system of face-to-face interactions characteristic at this economic level. The components of the density of communication, explored in another place, explain the cellular nature of the relatively homogeneous linguistic communities which are recognized by the natives as tribal units. The optimum or equilibrium population for such dialectical tribes in Australia statistically approximates 500 persons. Data are here presented to indicate that when such systems are disturbed, through fragmentation resulting from the introduction of new initiatory ceremonies, systematic forces restore these units to their optimum numbers with the passage of time. These are self-defining units, and they provide a basic demographic unit, called the Z-tribe, as a scale interval for measuring the effect of other social phenomena. With multivariant analysis this scale can be extended to measure the impact of various levels of political and social organization as well as patterns of face-to-face interaction based upon differing cultural and environmental variables. Appendices include some examples in which the Z-tribe scale could be usefully employed for further detailed analyses.