We present stable isotope and osteological data from human remains at Paloma, Chilca I, La Yerba III, and Morro I that offer new evidence for diet, lifestyle, and habitual mobility in the first villages that proliferated along the arid Pacific coast of South America (ca. 6000 cal BP). The data not only reaffirm the dietary primacy of marine protein for this period but also show evidence at Paloma of direct access interactions between the coast and highlands, as well as habitual mobility in some parts of society. By locating themselves at the confluence of diverse coastal and terrestrial habitats, the inhabitants of these early villages were able to broaden their use of resources through rounds of seasonal mobility, while simultaneously increasing residential sedentism. Yet they paid little substantial health penalty for their settled lifestyles, as reflected in their osteological markers of stature and stress, compared with their agriculturalist successors even up to five millennia later. Contrasting data for the north coast of Chile indicate locally contingent differences. Considering these data in a wider chronological context contributes to understanding how increasing sedentism and population density laid the foundations here for the emergence of Late Preceramic social complexity.

Archaeological work in the 1960s in the middle Nepeña Valley of coastal Peru (Figure 1) identified an artificial earthen mound or pyramid, approximately 15.5m high, with what was interpreted to be a crater dug into the top (Proulx 1968). This site has been variously known as Wanka, Huaca de Muro and El Bocón (PV31-55 in the Peruvian Ministry of Culture files). When viewed from a distance (Figure 2), the site resembles a volcanic cinder cone, such as the one in the Andahua Valley in southern Peru (Figure 3), and we have therefore named the site El Volcán. It should be noted, however, that there are no volcanoes in the vicinity of El Volcán to serve as models, nor indeed are any other examples of volcano-shaped structures known from Peru or elsewhere.

The nature of the adjustments made by the steadily increasing population of central coastal Peru in the Middle through Late Preceramic time periods can be examined by careful study of bioindicators. Nonspecific indicators of stress (NSIS) preserved in human remains provide independent evidence for validating paleodemographic hypotheses. If life expectancy improves over a period of time, one expects diminished indication of nonspecific stress. Decreasing stress over time also may imply increasing fertility in precontraceptive peoples, which, along with declining mortality, would lead to population growth. However, the converse does not follow; populations may grow over time whether responding to increasing, stable, or decreasing stress. Other factors, such as changing subsistence strategies or hybrid vigor, also may be useful in explaining diminished indications of either nonspecific stress or population increase. The complex relations among (a) population structure and density (PSD), (b) nonspecific indicators of stress, and (c) diet have not yielded deductions that could form a universal set of expectations. However, several kinds of adaptation that are distinct with respect to population growth and health status are considered and illustrated with analyses of 201 skeletons from the preagricultural village of Paloma in central coastal Peru.

The application of extremely complex multivariate models of classification to subjective inspectional methods of categorization is analyzed in detail, with the widely used Texas system of dart point typology as a case study. The history of the development of the Texas dart point typological system is sketched. An attempt by Gunn and Prewitt (1975) to objectify the classificatory system by multivariate methods is criticized. The techniques applied were too idiosyncratic to the particular data set used to be of predictive value. Discriminant function and multivariate classification analysis are discussed in detail, emphasizing simple geometrical examples by which the major principles may be grasped. Suggestions for improvement are offered for those who wish to follow Gunn and Prewitt in constructing automatic classification schemes.