More Than 20 Years Ago (1953) research was published on the relationship between mean annual rainfall and the size of the domain occupied by Australian Aboriginal tribal groups. When the original series of 409 tribes was refined to a more homogeneous basic series of 123 tribes, in which all water resources were locally earned as rainfall, the coefficient of correlation between the two variables approached 0.81. This coefficient expressed a systematic inverse logarithmic relationship between the amount of rainfall and the land required to support a tribal population. Further, it carried the implication that tribal populations tended to approximate a constant of 500 persons, based on estimates of tribal size from a variety of observers. The unexplained variance in this statistical relationship amounted to 35% of the total and included a variety of errors in ascertainment, as well as deviations in tribal numbers from the postulated constant. The exercise served to validate the assumption previously made (1950) that tribal numbers in Australia approached a constant value.

During the year 1973, as a Visiting Fellow in the Department of Anthropology and in the Department of Prehistory at the Australian National University, Canberra, it was possible to reexamine the relationships between Aboriginal men and their land in Australia at a much more complex level than previously undertaken. The high-speed computer has become available since the first attempt, and extensive resources in a first-class research institution provided the time and data necessary. During the 20 years that have intervened since 1953, the environmental data on continental Australia have increased enormously; it may now be one of the best studied continents in the world in these terms.