of cultural geography), at the University of California, Berkeley. As a result, cultural geography was long dominated by American writers. Sauer defined the landscape as the defining unit of geographic study. He saw that cultures and societies both developed out of their landscape, but also shaped them too. This interaction between the natural landscape and humans creates the cultural landscape. Sauer's work was highly qualitative and descriptive and was challenged in the 1930s by the regional geography of Richard Hartshorne. Hartshorne called for systematic analysis of the elements that varied from place to place, a project taken up by the quantitative revolution. Cultural geography was sidelined by the positivist tendencies of this effort to make geography into a hard science although writers such as David Lowenthal continued to write about the more subjective, qualitative aspects of landscape. In the 1970s, new kind of critique of positivism in geography directly challenged the deterministic and abstract ideas of quantitative geography. A revitalized cultural geography manifested itself in the engagement of geographers such as Yi-Fu Tuan and Edward Relph and Anne Buttimer with humanism, phenomenology, and hermeneutics. This break initiated a strong trend in human geography toward Post-positivism that developed under the label "new cultural geography" while deriving methods of systematic social and cultural critique from critical geography. Ongoing evolution of cultural geography Since the 1980s, a "new cultural geography" has emerged, drawing on a diverse set of theoretical traditions, including Marxist political-economic models, feminist theory, post-colonial theory, post-structuralism and psychoanalysis. Drawing particularly from the theories of Michel Foucault and performativity in western academia, and the more diverse influences of postcolonial theory, there has been a concerted effort to deconstruct the cultural in order to reveal that power relations are fundamental to spatial processes and sense of place. Particular areas of interest are how identity politics are organized in space and the construction of subjectivity in particular places. Examples of areas of study include: Feminist geography Children's geographies Some parts of tourism geography Behavioral geography Sexuality and space Some more recent developments in political geography Music geography Some within the new cultural geography have turned their attention to critiquing some of its ideas, seeing its views on identity and space as static. It has followed the critiques of Foucault made by other 'poststructuralist' theorists such as Michel de Certeau and Gilles Deleuze. In this area, non-representational geography and population mobility research have dominated.