[5][6] In 1949, Kluckhohn began to work among five adjacent communities in the Southwest: Zuni, Navajo, Mormon (LDS), Spanish-American (Mexican-American), and Texas Homesteaders[7] A key methodological approach that he developed together with his wife Florence Rockwood Kluckhohn and colleagues Evon Z. Vogt and Ethel M. Albert, among others, was the Values Orientation Theory.
In the same year his book Mirror for Man won the McGraw Hill award for best popular writing on science.
Kluckhohn wrote in 1959 that "in the light of accumulating information as to significantly varying incidence of mapped genes among different peoples, it seems unwise to assume flatly that 'man's innate capacity does not vary from one population to another'.... On the premise that specific capacities are influenced by the properties of each gene pool, it seems very likely indeed that populations differ quantitatively in their potentialities for particular kinds of achievement.
"[10] Clyde Kluckhohn died of a heart attack in a cabin on the Upper Pecos River near Santa Fe, New Mexico.
He was survived by his wife, Dr. Florence Rockwood Kluckhohn, who also taught anthropology at Harvard's Department of Social Relations.