The Late Holocene Dry Period (LHDP) was a one-plus millennial megadrought (3100–1800 cal BP) that delivered challenges and windfalls to Indigenous communities of the central Great Basin (United States). New pollen and sedimentation rate studies, combined with existing tree-ring data, submerged stump ages, and lake-level evidence, demonstrate that the LHDP was the driest Great Basin climate within the last 6,000 years—more extreme than the well-known Medieval Climatic Anomaly. New evidence reported here documents that most Great Basin archaeological sites south of 40° N latitude were abandoned during the long dry phase of the LHDP (3100–2200 cal BP), sometimes reoccupied during a wet interval (2200–2000 cal BP), and abandoned again during the most extreme drought (2000–1800 cal BP). Even in the face of epic drought, this is a story of remarkable survivance by some people who adjusted to their drought-stricken landscape where they had lived for millennia. Some moved on, but other resilient foragers refused to abandon their homeland, taking advantage of glacier-fed mountain springs with cooler alpine temperatures and greater moisture retention at high altitude, a result of early Neoglaciation conditions across many Great Basin ranges, despite epic drought conditions in the lowlands.

Current scholarship suggests that Neo-Eneolithic systems of settlement and subsistence in Eastern Europe were defined by short-to-medium range migration, while sparsely populated land in peripheral regions allowed for the continual colonization of new territories. We address the Eastern Tripolye Culture (ETC), a sub-group of the Cucuteni-Tripolye cultural complex that flourished ca. 4300–2950 BC by expanding into the forest-steppe ecozone of Central Ukraine. While a general lack of multi-layer sites complicates regional chronology, we resolve several longstanding questions in Ukrainian archaeological discourse by combining traditional relative chronologies of ceramic types with high-precision AMS dating of material from key sites. We offer a revision of the chronology of Tripolye BI and BI-II, which, rather than consisting of distinct “early” and “late” temporal periods, instead constitute a single period characterized by stylistic diversity in material culture. With an absolute chronology established, we then analyze the space-time distribution of sites, revealing a southwest-to-northeast migratory vector across Central Ukraine characterized by punctuated episodes of “leapfrog” colonization. The establishment of this vector by the ETC presages larger-scale population movements by the Western Tripolye Culture (WTC), which led to the establishment of the giant-settlement phenomenon during the first part of the 4th millennium BC.

Accelerator mass spectrometry radiocarbon (AMS 14C) dates (n = 78) from human bone collagen were analyzed in the largest high-resolution chronology study to date at the ancient city of Teotihuacan in central Mexico (ca. AD 1–550). Samples originate from the residential neighborhood of La Ventilla, located in the heart of this major urban center. Here, a trapezoidal model using Bayesian statistics is built from 14C dates combined with data derived from the stylistic analysis of ceramics from burial contexts. Based on this model, we suggest possible refinements to Teotihuacan’s ceramic chronology, at least within the La Ventilla neighborhood. We also explore the abandonment and reoccupation of La Ventilla after the political collapse of Teotihuacan in the Metepec and Coyotlatelco phases. Findings suggest that these ceramic phases began earlier than is currently projected and that the well-documented abandonment period of La Ventilla may have occurred more abruptly than originally estimated.

This article presents a compositional analysis of metal artifacts from the Postclassic period (a.d. 1100–1450) city of Mayapan, Yucatan, Mexico. We document metallurgical production at R-183, an elite residential group and one of the most significant archaeological contexts associated with metalworking at Mayapan. Salvage excavations in 1998 recovered a small cache containing 282 copper bells, two miniature ceramic vessels filled with metal, and production debris including loose casting sprues and miscast bells. Metallographic analysis of a small copper bell and wire fragments from the cache reveals lost-wax casting production techniques. X-ray fluorescence spectrometry (XRF) of metal artifacts provides insight into the range of metals used by the R-183 metalworkers, which included copper-lead, copper-tin, and copper-arsenic alloys, and how these alloys compare to assemblages recovered from other contexts at the city. Our findings strongly suggest the use of remelting and casting techniques, likely utilizing remelted metals of both West and central Mexican origin, together with the use of imported goods made from a range of copper alloys.

Campeche, one of the Spanish Empire's main Mexican ports, was a place where previously distinct cultures and populations intermingled during the colonial era (AD 1540–1680). Investigation of the town's central plaza revealed a Hispanic cemetery of multi-ethnic burials. The authors combine previous analyses with newly generated genome-wide data from 10 individuals to trace detailed life histories of the mostly young, local Indigenous Americans and first-generation European and African immigrants, none of whom show evidence of genetic admixture. These results provide insights into the individual lives and social divides of the town's founder communities and demonstrate how ancient DNA analyses can contribute to understanding early colonial encounters.

Data from rock shelters in southern Belize show evidence of tool making, hunting, and aquatic resource exploitation by 10,500 cal b.c.; the shelters functioned as mortuary sites between 7600 and 2000 cal b.c. Early Holocene contexts contain stemmed and barbed bifaces as part of a tradition found broadly throughout the neotropics. After around 6000 cal b.c., bifacial tools largely disappear from the record, likely reflecting a shift to increasing reliance on plant foods, around the same time that the earliest domesticates appear in the archaeological record in the neotropics. We suggest that people living in southern Belize maintained close ties with neighbors to the south during the Early Holocene, but lagged behind in innovating new crops and farming technologies during the Middle Holocene. Maize farming in Belize intensified between 2750–2050 cal b.c. as maize became a dietary staple, 1000–1300 years later than in South America. Overall, we argue from multiple lines of data that the Neotropics of Central and South America were an area of shared information and technologies that heavily influenced cultural developments in southeastern Mesoamerica during the Early and Middle Holocene.

Dental modification represents one interesting aspect of corporeal adornment in human history that directly reflects personal social identity. Tooth filing choices distinguished certain individuals at the urban, Maya political capital of Mayapan from 1150 to 1450 ad, along with cranial modification, nose and ear piercings, tattoos and body paint. Here we examine how filing teeth, considered a beautification practice for women at Spanish Contact in the sixteenth century, is distributed across a skeletal sample of males, females, elites and commoners in this city. We evaluate the normative claim of the Colonial period and determine that while predominantly females filed their teeth, most women chose not to. Sculptural art further reveals that male personages associated with the city's feathered serpent priesthood exhibited filed teeth, and we explore the symbolic meaning of filed tooth shape. Assessing the practice in terms of associated archaeological contexts, chronology and bone chemistry reveals that it did not correlate with social class, dietary differences, or birthplace. Residents of Mayapan, a densely inhabited, multi-ethnic city of 20,000, engaged with multiple material expressions of belonging to intersecting imagined communities that crosscut competing influences of polity, city, hometown and family scale identity. Tooth filing reflects identities at the individual or family scale.

Deposits linked to abandonment have been widely recorded across the Maya lowlands, associated with the final activities occurring in ceremonial areas of Classic Maya centers. Various models have been applied to explain the activities that lie behind the formation of these contexts, including those linked to rapid abandonment (e.g., warfare) and others focused on more protracted events (termination rituals, and/or pilgrimages). Here, we assess Bayesian models for three chronological scenarios of varying tempo to explain the formation of peri-abandonment deposits at Baking Pot, Belize. Using stratigraphic information from these deposits, hieroglyphic dates recovered on artifacts, and direct dates on human skeletal remains and faunal remains from distinct layers in three deposits in Group B at Baking Pot, we identify multiple depositional events that spanned the eighth to ninth centuries AD. These results suggest that the processes associated with the breakdown of institutionalized rulership and its command of labor to construct and maintain ceremonial spaces were protracted at Baking Pot, with evidence for the final depositional activity dated to the mid-to-late ninth century. This interval of deposition was temporally distinct from the earlier deposition(s) in the eighth century. Together, these data offer a detailed view of the end of the Classic period at Baking Pot, in which the ceremonial spaces of the site slowly fell into disuse over a period of more than a century.

We revisit the age and typological character of “Pox Pottery” that was reported in the 1960s by Charles Brush who considered it to be uniquely early (~2440 BC). Investigating the same two sites in coastal Guerrero where Brush excavated, we recovered Early Formative ceramics, some with the “pox” attribute. Here, we report potsherd frequencies for these deposits at both sites according to regional ceramic typologies, as well as AMS 14C dates used to establish a Bayesian stratigraphic chronology for each site to better constrain the age of these Early Formative period deposits. We argue that “Pox Pottery” is not a ceramic type per se and that the “pox” attribute occurs in multiple Early Formative period ceramic types. The earliest pottery is similar to other Red-on-Buff ceramic traditions from the Central Mexican Highlands and west of the Isthmus of Tehuantepec. Our chronological work demonstrates that these ceramics date between 1820 and 1400 cal BC, consistent with other recent studies indicating an early age of Red-on-Buff ceramics and suggesting shared cultural traditions distinct from the contemporary Locona interaction sphere that emerged in parallel.

This article emerged as the human species collectively have been experiencing the worst global pandemic in a century. With a long view of the ecological, economic, social, and political factors that promote the emergence and spread of infectious disease, archaeologists are well positioned to examine the antecedents of the present crisis. In this article, we bring together a variety of perspectives on the issues surrounding the emergence, spread, and effects of disease in both the Americas and Afro-Eurasian contexts. Recognizing that human populations most severely impacted by COVID-19 are typically descendants of marginalized groups, we investigate pre- and postcontact disease vectors among Indigenous and Black communities in North America, outlining the systemic impacts of diseases and the conditions that exacerbate their spread. We look at how material culture both reflects and changes as a result of social transformations brought about by disease, the insights that paleopathology provides about the ancient human condition, and the impacts of ancient globalization on the spread of disease worldwide. By understanding the differential effects of past epidemics on diverse communities and contributing to more equitable sociopolitical agendas, archaeology can play a key role in helping to pursue a more just future.

Shifting from shellfish collecting to fishing as a primary coastal foraging strategy can allow hunter-gatherers to obtain more food and settle in larger populations. On California's northern Channel Islands (NCI), after the development of the single-piece shell fishhook around 2500 cal BP, diet expanded from primarily shellfish to include nearshore fishes in greater numbers. During the Medieval Climatic Anomaly (1150–600 cal BP), settlement on the islands condensed to a small number of large coastal villages with high population densities supported largely by nearshore fish species including rockfishes, surfperches, and señoritas. Faunal data from five sites on western Santa Rosa Island (CA-SRI-15, -31, -97, -313, and -333) demonstrate an increase in nearshore fishing through time. We argue that demographic changes that occurred on the northern Channel Islands were accompanied by changes in subsistence strategies that were related in part to risk of failure when attempting to acquire different resources. As population density increased, the low-risk strategy of shellfish harvesting declined in relative importance as a higher-risk strategy of nearshore fishing increased. While multiple simultaneous subsistence strategies are frequently noted among individual hunter-gatherer communities in the ethnographic record, this study provides a framework to observe similar patterns in the archaeological record.

Analysis of human remains and a copper band found in the center of a Late Archaic (ca. 5000–3000 cal BP) shell ring demonstrate an exchange network between the Great Lakes and the coastal southeast United States. Similarities in mortuary practices suggest that the movement of objects between these two regions was more direct and unmediated than archaeologists previously assumed based on “down-the-line” models of exchange. These findings challenge prevalent notions that view preagricultural Native American communities as relatively isolated from one another and suggest instead that wide social networks spanned much of North America thousands of years before the advent of domestication.

Altica is a rare first-farming village site in the Basin of Mexico that has survived to modern times. Thus, it provides a glimpse into life during the Early–Middle Formative period. While valuable archaeological information on the village was recovered in excavation, only four burials comprising four individuals were recovered, a very small sample. Two individuals are older-aged females; the third, a middle-aged male, was accompanied by prestigious nonperishable goods and indicates that there are status differences even at this early date. The final individual was a young male buried in a deviant manner, suggesting possible foul play. While all individuals have indicators of periods of poor health, stable isotopes of carbon and nitrogen paint a more complete picture of the types of foods these individuals consumed over their lifetime. Radiogenic strontium isotopes of tooth enamel identify one individual, the young male buried in a deviant manner, as non-native to the Altica region. Thus, there is mystery in the manner of death, but even in this small sample, the wider connections Altica had that are so evident in the artefactual analysis are found in the skeletons. In addition, accelerator mass spectrometry radiocarbon dating provides a chronology of occupation through the people.

Teotihuacan's Tlajinga district is a cluster of neighborhoods on the southern periphery of the city best known for earlier investigations at Compound 33:S3W1. New research includes excavations at two other apartment compounds and along the southern extension of the Street of the Dead. Excavation contexts, major finds, chronology, and preliminary interpretations are the subject of this article. We highlight evidence attesting to a major obsidian-blade workshop at Compound 17:S3E1, offerings, and other features at that compound and Compound 18:S3E1, and the tempo and processes of urbanization viewed through well-recorded stratigraphic sequences of the compounds and the Street of the Dead. We conclude that significant occupation began in the Miccaotli phase, but it was not until some point in the Early Tlamimilolpa phase that the dominant housing type became apartment compounds; the continuation of the axis of Street of the Dead in the district was accomplished by excavating in the volcanic tuft substrate (tepetate) and could have been undertaken by the inhabitants of the district themselves; and the presence of items such as a sculpted stone face, marine shell, and polychrome pottery demonstrates that commoners at Teotihuacan enjoyed some access to finer items within the interregional economy.

Skeletal remains from Tlajinga 33 (33:S3W1) have been the focus of research in the southern sector of Teotihuacan since excavations took place in the 1980s. Recent excavations in Tlajinga Compounds 17 and 18 (17:S3E1 and 18:S3E1, respectively), located along the southern Street of the Dead, recovered nine additional skeletons. This article is a description of the burials from Compounds 17 and 18 and a comparative analysis of health, diet, and chronology across all three compounds (Compounds 17, 18, and 33). Here, we test the hypothesis that individuals between residential compounds at Tlajinga lived similar lives and that health and biogeochemical markers of individuals will reflect these similarities. Although the sample size is small, the paleopathological analysis of individuals at Compounds 17 and 18 indicates morbidity patterns similar to Tlajinga 33, but also that these residents were perhaps less susceptible to stressors during periods of juvenile growth. Stable carbon and nitrogen isotopes suggest that, overall, diets were analogous across compounds, but Compounds 17 and 18 were able to supplement their diet with a greater variety of plant resources. There were no clear dietary differences between higher and lower status individuals, however. Finally, accelerated mass spectrometry radiocarbon (AMS 14C) dates indicate that residential living may have occurred later at Compound 18 than at Compound 17 and Tlajinga 33.

Grave-good typologies have traditionally formed the basis for chronological frameworks in many areas of the world, including the Lika region of Croatia. Here, the authors report the first AMS radiocarbon dates from Late Bronze Age Lika (c. 1200–800 BC)—a period assumed to be synonymous with the emergence of the local Iapodian culture. Comparisons between the absolute dates and the relative chronological assignments of key burial contexts show inconsistencies between the dating methods that lead the authors to propose an alternative narrative for Iapodian emergence and socio-political reorganisation at the end of the Bronze Age.

Archaeological survey and excavations in the mangrove-estuary zone south of Izapa have generated an understanding of how the environment and human exploitation patterns changed during the Archaic and Formative periods. Archaic-period archaeological remains are not present, but the sedimentary record shows that Archaic people were clearing the coastal-plain forest for agricultural purposes. This activity augmented delivery of sediments to the littoral zone, which expanded the mangrove forest and created a productive environment that could be colonized by Early Formative villagers by around 1600 cal b.c. Population growth during the Early Formative created conditions that favored emergence of specialized pyro-industries, especially salt production, by around 1000 cal b.c. Production intensity increased thereafter, especially during the Late Formative period, coincident with the apogee of Izapa. Salt production became more episodic during the Terminal Formative period, when interior populations were declining to a nadir after cal a.d. 250.

Izapa is famous for its monumental architecture and extensive corpus of carved stelae dated to the Late Formative Guillén phase (300–100 cal b.c.). The site was first established, however, as the capital of a kingdom during the second half of the Middle Formative period (750–300 cal b.c.). Little is known of the first centuries of the site's occupation or how this early kingdom coalesced with Izapa as its capital. In 2012, the Izapa Regional Settlement Project (IRSP) excavated 21 test units and ran 10 radiocarbon accelerator mass spectrometry (AMS) dates in order to begin correcting this lacuna. These excavations were the first at the site to screen soil matrices and recover artifact samples that can be quantitatively analyzed.

We undertook excavations in areas north and south of Group B, the original center of Izapa. This work dates the northern expansion of the site's main platform (under Mound 30a) to the Terminal Formative Itstapa phase (cal a.d. 100–300) that resulted in a doubling of the platform's size. Further, we documented that there were three distinct construction episodes in the Terminal Formative expansion and that a central staircase and ramp were built of stone during the second episode. Buried below the Terminal Formative platform expansion was a white clay surface built during the Escalón phase (750–500 cal b.c.) and used through to Guillén times. At the long, linear Mound 62 that defines the eastern edge of Izapa's site core, we documented two episodes of Guillén-phase monumental construction. Buried below this construction fill at Mound 62, a hearth feature and stone alignment are dated to the late Middle Formative based on radiocarbon assays and the results of ceramic analysis. Excavations at Mound 72 and 73 documented that Izapa's E-Group (newly recognized with lidar [light detection and ranging] data) was established in the late Middle Formative period and then significantly augmented during the Guillén phase. The architectural program at Izapa saw its apogee during the Late Formative period, but was first established during the preceding centuries of the Middle Formative. Ten new AMS dates confirm the dating of the Escalón, Frontera, and Guillén phases to 750–100 cal b.c.

Ceramic analysis allowed us to differentiate quantitatively between midden deposits and construction fill through the site's occupation and to recognize domestic versus public spaces during the first centuries of the Izapa kingdom's coalescence. We identify late Middle Formative period middens based on the high density of ceramics in addition to good surface preservation of sherds and a lack of temporal mixing of types. The designation of high-artifact density middens contrasts with the contents of Late and Terminal Formative construction fill with lower ceramic sherd densities and mixing of temporally diagnostic types. Off-mound contexts (where construction fill was mined) had even lower ceramic densities than construction fill and the sherds were very eroded. Analysis of ceramic remains from late Middle Formative period midden deposits also allowed us to infer differences in public and domestic areas of the site during the first centuries of its occupation. Formal and metric variables from these ceramic assemblages identify dish-to-jar ratios that differentiate domestic contexts (with an assortment of vessel forms) from more publically oriented areas of the site (with more serving dishes). The differential distribution of rim diameters of fancy and plain dishes allows us to identify areas of Izapa where domestic activities predominate and indicate that more publically oriented feasting practices occurred at the site center near the main pyramid (Mound 30a) during the late Middle Formative period.

We report the discovery in the Greenland ice sheet of a discrete layer of free nanodiamonds (NDs) in very high abundances, implying most likely either an unprecedented influx of extraterrestrial (ET) material or a cosmic impact event that occurred after the last glacial episode. From that layer, we extracted n-diamonds and hexagonal diamonds (lonsdaleite), an accepted ET impact indicator, at abundances of up to about 5×106 times background levels in adjacent younger and older ice. The NDs in the concentrated layer are rounded, suggesting they most likely formed during a cosmic impact through some process similar to carbon-vapor deposition or high-explosive detonation. This morphology has not been reported previously in cosmic material, but has been observed in terrestrial impact material. This is the first highly enriched, discrete layer of NDs observed in glacial ice anywhere, and its presence indicates that ice caps are important archives of ET events of varying magnitudes. Using a preliminary ice chronology based on oxygen isotopes and dust stratigraphy, the ND-rich layer appears to be coeval with ND abundance peaks reported at numerous North American sites in a sedimentary layer, the Younger Dryas boundary layer (YDB), dating to 12.9 ± 0.1 ka. However, more investigation is needed to confirm this association.

Since the mid-19th century, western Oregon's Willamette Valley has been a source of remains from a wide variety of extinct megafauna. Few of these have been previously described or dated, but new chronologic and isotopic analyses in conjunction with updated evaluations of stratigraphic context provide substantial new information on the species present, timing of losses, and paleoenvironmental conditions. Using subfossil material from the northern valley, we use AMS radiocarbon dating, stable isotope (δ13C and δ15N) analyses, and taxonomic dietary specialization and habitat preferences to reconstruct environments and to develop a local chronology of events that we then compare with continental and regional archaeological and paleoenvironmental data. Analysis of twelve bone specimens demonstrates the presence of bison, mammoth, horse, sloth, and mastodon from ~ 15,000–13,000 cal yr BP. The latest ages coincide with changing regional climate corresponding to the onset of the Younger Dryas. It is suggested that cooling conditions led to increased forest cover, and along with river aggradation, reduced the area of preferred habitat for the larger bodied herbivores, which contributed to the demise of local megafauna. Archaeological evidence for megafauna–human interactions in the Pacific Northwest is scarce, limiting our ability to address the human role in causing extinction.