expansion of Olmec culture beyond the Gulf coast of Veracruz and Tabasco.

In Mexico South (1946b), Covarrubias published the first detailed summary of the Olmec civilization, including a brilliant analysis of iconography. One of the finest books ever written about Mexico, the work includes chapters on the archaeology, ethnography, folklore, and history of the peoples of the Isthmus of Tehuantepec in Southern Mexico.

The 1940s ended with a transformation of the fields of study and theoretical goals of Mexican archaeology. Investigations were made based on the theories of cultural evolution and Marxism, often with an emphasis on the development of social stratification and the interrelationships between human populations and their natural environments. Paul Kirchhoff, Pedro Armillas, and Othón de Mendizábal were pioneers in these new research orientations. Mendizábal, principally a social anthropologist, used archaeological and ethnological data and published a series of analyses concerning the economic systems of specific native groups and the cultural evolution of major regions in the central highlands (Mendizábal 1946).

Paul Kirchhoff, a German social anthropologist who went to Mexico during the 1930s, made fundamental contributions to archaeology. In 1943 he produced the first coherent definition of Mesoamerica (it was Kirchhoff who proposed the term) as a cultural area, mainly using ethnohistoric and ethnographic traits to define the cultural elements. He also published studies of the ecological variations in Mesoamerica and neighboring areas, attempting to correlate them with different social structures, subsistence systems, and patterns of resource exploitation among pre-Hispanic peoples. He wrote ethnohistorical analyses of ancient chronicles, concentrating especially on histories of the Toltecs and the migrations of different ethnic groups in central Mexico. His classes on Marxism, social organization, ethnology, and other subjects in the National School of Anthropology and History profoundly influenced several generations of Mexican anthropologists and archaeologists.

The investigations and classes of Pedro Armillas during the 1940s and 1950s also had profound effects on the development of Mexican archaeology. He was the original exponent of cultural ecology in Mesoamerican studies, and his many students have generated projects and investigations inspired by his ideas. Armillas was instrumental in disseminating the writings and concepts of vere gordon childe in Mexico, writings concerning cultural evolution, urbanism, and other fundamental processes.

../images/Mexico1.jpg

A carved statue found in the ancient Toltec city of Tula

(Gamma)

Armillas did fieldwork in many regions. His excavations in Teotihuacán formed the basis for his (1950) chronology of the basin of Mexico, which is essentially still valid. Using data from surveys of various regions in the state of Guerrero, he proposed a model for the major systems of agriculture in Mesoamerica (1947). He studied fortified centers in the central highlands (1948) and conducted surveys in the Valley of Puebla-Tlaxcala in an attempt to correlate specific centers with ethnic groups mentioned in pre-Hispanic chronicles. In 1949 he published a famous essay proposing a framework for cultural evolution in Mesoamerica, emphasizing technology