In the highlands of northern Chile, research on industrial mining camps and agropastoral sites (estancias) shows the relevance of a contemporary archaeology perspective for studying the impacts of capitalist expansion, ruination and deindustrialisation for local Indigenous communities.

The Tupí linguistic group is one of the most widespread in South America, indicating a deep history of population movement, yet the ancestral homeland and migration routes of descendant groups remain the subject of debate due to the fragmentary nature of the Amazonian archaeological record. Using a database of more than 660 georeferenced dates from sites of the Tupinambá and Guaraní peoples, the authors deploy a mobility model to investigate the timing of population movements, viable routes and the distances achieved. The results create a more nuanced understanding of the rhythms of migration through an ecologically and socially complex landscape.

Excavations at the Infantas complex in Chillón Valley, Perú, revealed a U-shaped monumental centre with a central mound, clay staircase and columned atrium. Aligned with structures from the Rímac and Lurín valleys, these complexes anchored ritual-political power, serving as hubs for ideological integration and territorial organisation in early Andean societies.

Since 2015, four non-invasive campaigns have surveyed the San José Galleon shipwreck in the Colombian Caribbean, providing valuable insights into the age and provenance of artefacts found on the seabed. Numismatic, archaeological and historical approaches have been employed to analyse a collection of gold coins recorded within this underwater context.

The nature and extent of the Tiwanaku state expansion in the Andes during the second half of the first millennium AD continues to be debated. Here, the authors report on the recent discovery of an archaeological complex 215km south-east of Tiwanaku, where a large, modular building with an integrated, sunken courtyard strongly resembles a Tiwanaku terraced platform temple and demonstrates substantial state investment. Constructed, the authors argue, to directly control inter-regional traffic and trade between the highlands and the eastern valleys of Cochabamba, the complex represents a gateway node that effectively materialised the power and influence of the Tiwanaku state.

Monumental constructions are often associated with developed power structures, exploiting unequal access to resources to control large labour forces. Yet archaeological research worldwide increasingly shows that this model is not only an oversimplification, but often is also wrong. Here, the authors explore the burial mounds at Kaillachuro in the Peruvian Andes, and present new radiocarbon dates that position these mounds as the earliest evidence of monumental architecture in the Titicaca Basin. Built over 2000 years through recurring acts of communal memorialisation, this novel architectural tradition forces us to reflect on the role of ritual in socioeconomic transformations of highland Andes communities.

Effective conservation management of threatened species with transboundary distributions is a challenge, requiring international coordination to ensure that country-specific actions align with regional imperatives. Many international conservation efforts overlook species needing attention and fail to incorporate the field expertise of local researchers in regional-level assessments. Here we focus on the taruka Hippocamelus antisensis, a threatened and little-studied deer of the Central Andes Ecoregion in South America. Since 2016, experts, managers and governmental authorities from all countries encompassing the species’ range have gathered to collate information about its presence and coordinate efforts to conserve it. We constructed taruka distribution models using historical records and more recent sightings reported during the last 50 years. Our findings revealed several critical insights: slope, normalized difference vegetation index (NDVI) during the dry season, and daily and seasonal temperature variability are primary predictors of taruka distribution, and the largest part of its range is in Peru (54%), followed by Bolivia (30%), Argentina (10%) and Chile (6%). The species’ core distribution is confined to the western and eastern limits of the Central Andes Ecoregion, bordered by the Sechura and Atacama Desert to the west and the Yungas Forest to the east. Protection is limited, with only 12 and 8% of the core and non-core areas, respectively, of the species’ range under formal protection. We recommend safeguarding connectivity of the core distribution by establishing transboundary protected areas, improving taruka coexistence with local communities, strengthening and formalizing international collaboration amongst taruka experts and raising the species’ appeal amongst policymakers and the public. In particular, we hope to encourage international collaboration between Southern Hemisphere specialists. This is important because these researchers have extensive field knowledge that could improve global conservation efforts, especially in regions that lack adequate conservation funding.

The sacralisation of mountains played an important role in the expansion of the Inca Empire into the south-central Andes during the mid-second millennium AD. Here, the authors compare archaeological material from sacralised mountains in north-western Argentina, highlighting not just the shared attributes of high-altitude sites but also the diversity of ways in which Inca dominion over the mountains could be materialised. Focusing on Mount Inca Viejo, in the Argentine province of Salta, the authors further explore the characterisation of sacred mountains and the significance of mining and mineral acquisition as a motivator for Inca expansion.

While most higher taxa in the Hemiuroidea exhibit remarkable diversity and thrive worldwide in marine ecosystems, a few groups have successfully radiated into freshwater environments. Among them, species of Thometrema are well known from freshwater and brackish fishes in the New World. In this study, specimens of Thometrema from a single specimen of the endangered pimelodid catfish Steindachneridion scriptum in the Upper Paraná River basin, State of São Paulo, Brazil, were subjected to morphological, ultrastructural (first scanning electron microscopy data for the genus) and molecular analyses. Newly obtained sequences of the partial large subunit nuclear ribosomal RNA (28S rDNA) and partial mitochondrial cytochrome c oxidase subunit I (COI mtDNA) provided strong evidence supporting the identification of the specimens as T. patagonicum, a trematode previously known only from endemic percichthyid fishes (Percichthyidae) in the Argentinian Patagonia. This unexpected finding, along with critical morphological evaluation of new and deposited material, led us to propose T. overstreeti and T. bonariense as junior synonyms of T. patagonicum. Moreover, we reassessed certain morphological features, revealed new potential distinguishing characters (papillae) and raised doubts about the taxonomic value of commonly used features for species differentiation (e.g., vitellarium masses). To overcome taxonomic problems in Thometrema due to the paucity of morphological features to clearly set species boundaries, new descriptions could leverage integrative approaches, as employed here, to establish robust species hypotheses and ultimately unravel the actual species composition in the Americas.

Under what conditions do South American states create regional institutions that consolidate or undermine the liberal international order (LIO)? To address this question, we compare two cases of contestation of the LIO through counter-institutionalization in the domains of migration and election monitoring, both of which are closely related to the LIO’s core political principles. We argue that the variation in the effects of counter-institutionalization—LIO-consolidating in the case of migration and LIO-undermining in the case of election monitoring—results from the interaction of two explanatory factors: the source of dissatisfaction with the LIO’s norms and institutions in a specific domain, and the preferences of the state that exercises regional leadership in support of counter-institutionalization. The article sheds light on the coexistence of liberal and illiberal tendencies in South America’s regionalism and contributes to the debate on the determinants and effects of contestations of the LIO in the Global South.

This article examines the significance of mobility and transportation infrastructure in the early development of pan-Americanism and the formation of a vision of global transportation in South America in the late nineteenth century. Focusing on the 1880s and 1890s, I explore the connection between transportation and the economic and cultural expansionism of the United States, pan-American debates on intercontinental steamship service and an inter-American railroad, and South American approaches to international transportation, which both included and transcended the Americas. My case study contributes to scholarship on the global history of mobility and transportation by showing how, despite the intention of the United States to establish hemispheric exclusivity and hegemony, transportation became a subject of multilateral cooperation. South American experts and diplomats, I argue, renegotiated and reinterpreted the meaning of pan-American infrastructure, integrating it into a broader vision of global transportation that positioned their countries more prominently in worldwide traffic networks.

The capacocha was one of the most important types of Inca sacrifices. Road stations (tambos) were built for the pilgrims who travelled to mountain peaks with the sacrifices. Spatial analysis of two tambos on the slopes of the Pichu Pichu and Chachani volcanoes in Peru reveals segregation in the sacred landscape.

Although radiocarbon-accelerator mass spectrometry (14C-AMS) is an important tool for the establishment of soil chronology, its application is challenging due to the complex nature of soil samples. In the present study, chemical extraction methodologies were tested to obtain the most representative age of Amazonian soil deposition by 14C-AMS. We performed acid hydrolysis with different numbers of extractions, as well as treatments combining acid and bases and quartered and non-quartered samples. The ages of the soil organic matter (SOM) fractions were compared to the ages of naturally buried charcoal samples at similar depths. The results showed that the age of the non-hydrolyzable inert fraction of soil was closer to the age of charcoal and older than the ages of humin. It was also observed that the quartering process can influence the results, since the dating of the humin fraction showed variability in the results. Our results are important to provide information about the most suitable method for the 14C-AMS dating of soil samples for paleoenvironment reconstruction studies.

Radiocarbon dates can offer important corollaries for historic events and processes, including territorial expansion and consolidation in early empires. Eighteen new radiocarbon dates from test excavations at Ak'awillay, near the Inca imperial capital of Cuzco, reveal new perspectives on interactions between the Incas and Xaquixaguana Valley groups. Rather than persisting as a regional centre, Ak'awillay declined well before early Inca expansion, remaining largely unoccupied until after an extensive empire had been established. This new chronology adds nuance to the growing understanding of local group interactions and how they contributed to Inca state development and imperial expansion.

At Ollantaytambo, in the Cusco region of Peru, the Inka (c. AD 1400–1532) built an elaborate anthropogenic landscape to facilitate intensive agriculture. After the 1532 Spanish invasion of the region, this landscape was reshaped by the introduction of new plants and animals, colonial land-management practices and demographic transformations. Here, the author employs botanical data from a derelict Inka-era reservoir to evaluate the timing and character of colonial transformations to the local agroecology. These transformations, they argue, tended towards agricultural deintensification, but this process did not begin until decades after the Spanish invasion.