The document outlines four distinct modes of resource use throughout human history:
1) Hunting-gathering - Societies depended on human and animal muscle power to fulfill subsistence needs from naturally available resources. Social groups were small and kin-based with minimal division of labor. Ecological impact was minimal.
2) Pastoralism - The domestication of animals allowed for flexibility in habitat use. Nomadic pastoral groups created greater resource flows over larger distances and exchanged materials with settled groups. Private property emerged but land was still held communally. Pastoralism contributed somewhat to overgrazing and ecological degradation.
3) Settled cultivation - Agriculture became more significant in moderate rainfall areas. Settlements grew larger