ABSTRACT
When human numbers were small and population densities were low, humankind adapted both biologically and behaviorally existing ecosystems without extensive modification of the system's structure. Thus, for the major portion of human prehistory, it is possible to delineate distinct kinds of adaptations to the different ecosystems in which the human species participated; tropical, temperate woodland, grassland, boreal forest, and so on. But with the harvesting of unearned resources toward the end of the Pleistocene and the resulting sedentism and population expansion, all three trends systematically accelerated, together with cultural evolution. It is enough to demonstrate that technology and good intentions, properly funded, are not enough. The analytic reductionist thinker examines one part of the system since it affects another part, looks for straight lines of cause and effect. This simple logic is dangerous, because it is based on the entirely false assumption that causality in nature is linear rather than systemic.
