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The non-equilibrium paradigm of range ecology (NEPORE) emerged in the late 1980s in international range management circles to specifically address the ecological dynamics of arid and semi-arid rangeland systems. Based mainly on lessons from Africa, it questioned existing equilibrium-based theories of vegetation change and argued that the animal density-dependent model is not useful in highly variable and unpredictable environments. NEPORE's focus on abiotic determinants of primary productivity served to downplay fears of overgrazing in arid systems, coupled to the belief that livestock grazing would be unlikely to cause range degradation under normal circumstances. Such a view is premised on the expectation that grazing pressure will decline following periods of low rainfall and low productivity, due to livestock removal either through mobility or mortality. This scenario does not consider that livestock might receive supplemental feed from outside sources, like in some parts of Inner Mongolia where, since the 1980s, market forces have swamped traditional, more mobile, pastoral practices and overgrazing appears to remain a leading factor in the reduction of the productive potential of rangeland through soil loss and vegetation change. Livestock numbers still fluctuate with precipitation, but are also heavily influenced by market prices for livestock, imported forage, and micro-credit availability. If the market price of meat is high enough to cover the cost of buying forage from elsewhere, in drought years herders can keep and even increase their herd size. Market forces allow sustained high livestock populations, regardless of rainfall, resulting in consistent livestock perturbation that has caused vegetation to cross thresholds and to state changes in rangelands unaccounted for by standard interpretations of NEPORE.