farmers. Relationship to anthropology and geography Originating in the 18th and 19th centuries with philosophers such as Adam Smith, Karl Marx, and Thomas Malthus, political economy attempted to explain the relationships between economic production and political processes. It tended toward overly structuralist explanations, focusing on the role of individual economic relationships in the maintenance of social order. Eric Wolf used political economy in a neo-Marxist framework which began addressing the role of local cultures as a part of the world capitalist system, refusing to see those cultures as "primitive isolates". But environmental effects on political and economic processes were under-emphasised. Conversely, Julian Steward and Roy Rappaport's theories of cultural ecology are sometimes credited with shifting the functionalist-oriented anthropology of the 1950s and 1960s and incorporating ecology and environment into ethnographic study. Geographers and anthropologists worked with the strengths of both to form the basis of political ecology. PE focuses on issues of power, recognizing the importance of explaining environmental impacts on cultural processes without separating out political and economic contexts. The application of political ecology in the work of anthropologists and geographers differs. While any approach will take both the political/economic and the ecological into account, the emphasis can be unequal. Some, such as geographer Michael Watts, focus on how the assertion of power impacts on access to environmental resources. His approach tends to see environmental harm as both a cause and an effect of “social marginalization”. Political ecology has strengths and weaknesses. At its core, it contextualizes political and ecological explanations of human behavior. But as Walker points out, it has failed to offer “compelling counter-narratives” to “widely influential and popular yet deeply flawed and unapologetic neo-Malthusian rants such as Robert Kaplan's (1994) 'The coming anarchy' and Jared Diamond's (2005) Collapse (385). Ultimately, applying political ecology to policy decisions – especially in the US and Western Europe – will remain problematic as long as there is a resistance to Marxist and neo-Marxist theory. Andrew Vayda and Bradley Walters (1999) criticize political ecologists for pre-supposing “the importance ... of certain kinds of political factors in the explanation of environmental changes” (167). Vayda and Walter's response to overly political approaches in political ecology is to encourage what they call “event ecology”, focusing on human responses to environmental events without presupposing the impact of political processes on environmental events. The critique has not been taken up widely. One example of work that