Despite the political fragmentation of Central Mexico following the breakup of the Teotihuacan state, the Epiclassic Coyotlatelco ceramic style was widespread in the Basin of Mexico and adjoining areas. Instrumental neutron activation analysis (INAA) was used to determine sources of Coyotlatleco pottery from Teotihuacan in collections made by the Teotihuacan Mapping Project and from rural sites in the Teotihuacan Valley. A sample of Mazapan, Early Postclassic pottery from rural sites also was analyzed. The INAA results indicate that most Coyotlatelco serving vessels consumed at Teotihuacan and in rural villages in the Teotihuacan Valley were locally made with few imports from elsewhere in the Basin. Following the decline of the Teotihuacan state Epiclassic polities in the Basin of Mexico had an “inward” economic orientation. During the Early Postclassic rural villagers continue to mostly consume locally made Mazapan pottery. We discuss implications of these findings for models of the Postclassic political economy and the Classic to Postclassic transition.

Alternative models of residential mobility have been proposed to explain the development and spread of Tiwanaku influence across the south central Andes. Within the Osmore drainage, the rich Moquegua Valley has been hypothesized as the site of a significant colonization event (or events) whereby both the natural and human landscape was transformed and integrated into the expansive Tiwanaku state. In this research, the impact of altiplano colonization is inferred from temporal and spatial patterns of genetic variation within and among native groups. Mitochondrial DNA haplogroup frequencies are used as the measure of genetic variation. The haplogroup data are determined for Moquegua Valley archaeological samples (Chen Chen site; A.D. 785-1000) and are compared to published data from 58 other ancient and contemporary native groups. The results support temporal and spatial genetic continuity in the south central Andes for the last 1,000 years. Contemporary Aymara speaking groups are exceptions to this pattern, perhaps because of recent population decline. While the altiplano colonization hypothesis is not rejected, moderate gene flow and relatively large population sizes likely characterized much of south central Andean prehistory regardless of the contribution from Tiwanaku colonization events.

Prehispanic socioeconomic organization along the Andean coast is often understood with the “horizontality” model. In this scenario, coastal communities engaged in specialized economic activities and exchanged for products of other specialized communities. Throughout the lower reaches of the Osmore drainage on the south coast of Peru, settlement distribution and both residential and mortuary assemblages of Late Intermediate period Chiribaya partially reflect this pattern. However, investigations at the site of Wawakiki do not support a strict pattern of specialization, demonstrating that some communities along the intervalley coast emphasized a diversified production strategy. This practice appears late in the Chiribaya cultural sequence established for the Ilo valley, and it appears to have constituted part of a socioeconomic response to increasing hardships between about A.D. 1200-1400. Late Chiribaya populations responded to the combined effects of demographic growth and diminishing agricultural potential by (1) expanding into the relatively unpopulated intervalley coast, and (2) placing greater emphasis on diversified community level production along the coast. These results indicate that the variation observed in socio-economic organization should be interpreted within a more historically contingent and dynamic framework than that offered by a general model alone.

The introduction of the type-variety system as a means of classifying Maya ceramics had considerable success in promoting communication among researchers. There was hope that it would prove to be possible to devise a single unitary system of ceramic analysis based on type-variety. We believe that such a hope was doomed to failure. Ceramic complexity is too great to be subsumed in any single typological system. Attempts to incorporate the many variables involved within a type-variety analysis have usually resulted in neglect of some and the loss of important information. Instead, we advocate the use of multiple systems of classification. We suggest that at least three separate classifications should be done based on (1) surface finish, (2) vessel shapes (forms), and (3) pastes. For ceramics having highly decorated vessels, another separate classification of decoration is desirable. A final and vitally important objective is to investigate covariation among the classifications of shape, surface, decoration, and paste. We believe that these relationships can be seen more clearly by the use of multiple classifications than by incorporating all into a single typological system in which such variation is all too often hidden.

A long-standing understanding of the Maya highlands suggests that the Postclassic period was characterized by increased warfare and conflict over the preceding Classic period, as seen in settlement patterns and defensive features. Based on recent archaeological work in Guatemala's western highlands, we argue that the archaeological evidence does not support this conclusion; defensive characteristics are also common in the Classic period. Drawing on examples from the Huista-Acatec region of the Cuchumatán Mountains, a typology of defensive characteristics is presented, along with comparative examples elsewhere in the Maya highlands. We suggest that these material correlates of defensibility, while showing that conflict was a central concern in both the Classic and Postclassic periods, lay the foundation for future studies of warfare in the Maya highlands. These insights have implications for the study of settlement pattern defensibility beyond the Maya highlands, including the construction and use of defensive feature typologies, the appropriateness of categorizing societies as either peaceful or militaristic, and the wider identification of cultural continuity.

Aguada Zacatal is a reservoir located within a bajo 4 km west of Nakbe, Petén, Guatemala. It is 100 m in diameter and the surrounding berm is approximately 1 m tall. The small Classic period site of Zacatal is adjacent to the aguada. The reservoir's artificial lining prevents dry season desiccation and enhances microfossil preservation. In 1998 a 335 cm sediment core was taken from the center of the reservoir and analyzed for pollen, microscopic charcoal, and total organic matter. Core chronology, based on two AMS radiocarbon determinations, shows the record covers the period from A.D. 695 to present. Only the upper 113 cm contained well-preserved microfossils. The pollen record clearly documents a period of agricultural activity followed by abandonment and forest succession. In the agricultural period (A.D. 695-840), corn pollen is found in conjunction with disturbance indicators. After the abandonment at approximately A.D. 840, the record is dominated by aquatic pollen types and corn pollen is absent. This shift in pollen spectra represents the end of the Classic period.