Carneiro's theory has been criticized by the Dutch "early state school" emerging in the 1970s around cultural anthropologist Henri J.M. Claessen, on the ground that considerable contrary evidence can be found to Carneiro's theory. There are also cases of circumscribed environments and violent cultures which have failed to develop states, for example in the narrow highland valleys of interior Papua New Guinea, or the north west Pacific coastlines of North America. Also for example, the formation of some early states in East Africa, Sri Lanka, and Polynesia do not easily fit with Carneiro's model.