Archaeological research on the architecture and sculpture of Tiwanaku society in the south-central Andes follows two separate paths: one emphasizes iconographic interpretation, whereas the other studies lithic materials’ origin and spatial relations. This separation, stemming from dualistic modern thought, is an obstacle to a comprehensive understanding of lithic sculptures and their role in Tiwanaku society. This article focuses on the Ponce and Bennett monoliths, the two largest and most complex sculptures of the Tiwanaku ceremonial center. It presents the results of an iconographic analysis identifying minimal design components ordered in a three-level nested hierarchy and their distribution over the spatial structures of both sculptures. This analysis incorporates existing information about lithic materials and quarries, the monoliths’ locations, and spatial relationships. All those data are interpreted in the light of Aymara and Quechua ontologies about the relationships between mountains, stones, and images. Characterizing aspects of the Tiwanaku site and its role in lithic production, this article extends the limits of Tiwanaku society to include nonhuman agents and suggests that we overcome anthropocentric biases.

Sealings recovered from the Omo M10 temple, a provincial center of the Andean Tiwanaku state (AD 500–1100), and from the Muru Ut Pata neighborhood of the Tiwanaku capital, as well as a signet ring from the Akapana East complex of Tiwanaku's highland capital, shed light on the hitherto undocumented use of seals and sealings in Central Andean complex society. The identification of Tiwanaku sealings related to the signet ring seal has implications for understanding the transmission of identity, authority, and authenticity over time and distance in early Andean states.

Archaeologists working in the Late Formative Lake Titicaca Basin have identified several “transit communities”—villages that benefited from long-distance exchange. Some scholars suggest that such places played a key role in the development of the Middle Horizon city of Tiwanaku. In this article, we explore the movement of plant goods into transit communities during both the Late Formative (300 BC–AD 500) and Middle Horizon (AD 600–1100) periods. After presenting the current understanding of transit communities, we summarize previous work on both local plants, including tubers and quinoa, and the presence of maize. We then report on a recent microbotanical study of ceramics recovered from excavations at Late Formative Challapata (in the eastern basin) and a burial from the Middle Horizon occupation at Chiripa (in the southern basin). For the first time we identify lowland tubers in the Lake Titicaca Basin, including yuca, sweet potato, and arrowroot. These findings reveal the critical importance of microbotanical analyses for tracing regional connections and foodways in emergent Middle Horizon worlds, as well as the need for more complex interpretive models for things/plants-in-motion.

The collapse of the Tiwanaku state around AD 1000 resulted in dramatic changes in the areas of its former colonies such as the Moquegua Valley, which featured the largest Tiwanaku communities outside the Altiplano. The inhabitants of these former colonies were forced to relocate to the areas north of Moquegua, including the Tambo River estuary (Arequipa Department, Province of Islay). This relocation has been confirmed at La Pampilla 1, where a large graveyard featuring funerary contexts of the postcollapse communities of Tiwanaku-Timulaca was found, with a calibrated 14C date between the eleventh and thirteenth centuries AD. In this article we discuss the results of excavations and analyses conducted at the La Pampilla 1 graveyard, the first systematically researched Tiwanaku site in the Tambo Valley: these findings confirm the existence of a relatively large, terminal-phase Tiwanaku population, represented by Tumilaca funerary contexts.

As in other examples of state collapse, political disintegration of the Tiwanaku state circa AD 1000 was accompanied by considerable cultural continuity. In the Moquegua Valley, Peru, the location of the largest Tiwanaku communities outside the altiplano, settlements and practices associated with this postcollapse cultural continuity are termed Tumilaca. Previous research indicated that Tumilaca was short-lived, with all vestiges of Tiwanaku gone from Moquegua's archaeological record by the thirteenth century when the valley was subsequently characterized by Estuquiña-style materials. This article discusses radiocarbon dates from Tumilaca la Chimba, a village established as the political authority of the Tiwanaku state waned. The 21 absolute dates from Tumilaca domestic, public, and funerary contexts span at least 350 years, from the late tenth to the mid-fourteenth centuries AD. They suggest that (1) Tiwanaku-affiliated communities endured well into the later Late Intermediate Period (AD 1200–1470); (2) ongoing debates about the emergence of Estuquiña communities must consider the role of terminal Tiwanaku populations; and (3) analyses of postcollapse continuity can be enhanced by considering peripheral locales and the particularities of continuity.

The Cochabamba Basin (Bolivia) is on the ancient road network connecting Andean and lowland areas. Little is known about the longevity of this trade route or how people responded to past environmental changes. The eastern end of the Cochabamba valley system constricts at the Vacas Lake District, constraining the road network and providing an ideal location in which to examine past human–environmental interactions. Multiproxy analysis of sediment from Lake Challacaba has allowed a c. 4000 year environmental history to be reconstructed. Fluctuations in drought tolerant pollen taxa and calcium carbonate indicate two periods of reduced moisture availability (c. 4000–3370 and c. 2190–1020 cal yr BP) compared to adjacent wetter episodes (c. 3370–2190 and c. 1020 cal yr BP–present). The moisture fluctuations broadly correlate to El Niño/Southern Oscillation variations reported elsewhere. High charcoal abundance from c. 4000 to 2000 yr ago indicates continuous use of the ancient road network. A decline in charcoal and an increase in dung fungus (Sporormiella) c. 1340–1210 cal yr BP, suggests that cultural changes were a major factor in shaping the modern landscape. Despite undisputable impacts of human populations on the Polylepis woodlands today, we see no evidence of woodland clearance in the Challacaba record.

Ritual practices and their associated material paraphernalia played a key role in extending the reach and ideological impact of early states. The discovery of a leather bag containing snuffing tablets and traces of psychoactive substances at Cueva del Chileno in the southern Andes testifies to the adoption of Tiwanaku practices by emergent local elites. Tiwanaku control spread over the whole of the south-central Andes during the Middle Horizon (AD 500–1100) but by the end of the period it had begun to fragment into a series of smaller polities. The bag had been buried by an emergent local elite who chose at this time to relinquish the former Tiwanaku ritual practices that its contents represent.

Recording devices formed of knotted cords, known as khipus, are a well-known feature of imperial administration among the Inka of Andean South America. The origins and antecedents of this recording system are, however, much less clearly documented. Important insights into that ancestry are offered by a group of eight khipus dating from the later part of the Middle Horizon period (AD 600–1000), probably used by the pre-Inka Wari culture of the central Andes. This article reports the AMS dating of four of these early khipus. A feature of the Middle Horizon khipus is the clustering of knots in groups of five, suggesting that they were produced by a people with a base five number system. Later, Inka khipus were organised instead around a decimal place-value system. Hence the Inka appear to have encountered the base five khipus among Wari descendant communities late in the Middle Horizon or early in the Late Intermediate period (AD 1000–1450), subsequently adapting them to a decimal system.

The temptation to equate environmental change with archaeologically observed events is always with us, and matching a climatic downturn with civilisation collapse is perhaps more attractive then ever. The archaeologically observed collapse of the Tiwanaku civilisation in the twelfth century AD has been specifically related to a prolonged drought which would have affected the people’s ability to produce food. However, a careful scrutiny of the data from ice cores and lake sediments persuades the author that no such drought can be inferred: the evidence for climatic change is of quite a different scale and order to the archaeological changes and cannot be used as an explanation of social events.