Dependency theory
The anthropologists Marshall Sahlins and Elman Service prepared an edited volume, "Evolution and Culture", in which they attempted to synthesise White's and Steward's approaches. Other anthropologists, building on or responding to work by White and Steward, developed theories of cultural ecology and ecological anthropology. The most prominent examples are Peter Vayda and Roy Rappaport. By the late 1950s, students of Steward such as Eric Wolf and Sidney Mintz turned away from cultural ecology to Marxism, World Systems Theory, Dependency theory and Marvin Harris's Cultural materialism.