The Brazil Nut tree (Bertholletia excelsa, Lecythidaceae) is a species of considerable historical, economic and ecological importance in South America. Radiocarbon dating indicates some individuals can live from hundreds to more than 1000 years, which means they have the potential to reconstruct deep time growth patterns and their relationship to anthropogenic management or climate change from pre-colonial to present times. However, age estimates vary considerably amongst trees dated with different methods (i.e. tree-ring analysis, radiocarbon-dating, and repeated diameter measurements). Here we analyze living Brazil Nut trees growing in four distinct regions across the Brazilian Amazon using two dating methods: tree-ring counting and radiocarbon dating. Our results show that the congruence between the two methods varies amongst regions, and the highest congruence is found at the site of Tefé, Amazonas. This region features archaeological sites with anthropogenic Terra Preta soils, and is known for its long-term human forest management. This management likely enhanced light and nutrient availability, which possibly enabled the trees to grow at higher rates and form annual rings. Our findings highlight the need for better understanding of the growth of Brazil Nut trees for ecological research, but also the potential of dendrochronology for exploring climate change and human-forest interactions in the Amazon Basin.

Northern Arizona University, Flagstaff, Arizona, USA, recently installed a MIni CArbon DAting System (MICADAS) with a gas interface system (GIS) for determining the 14C content of CO2 gas released by the acid dissolution of biogenic carbonates. We compare 48 paired graphite, GIS, and direct carbonate 14C determinations of individual mollusk shells and echinoid tests. GIS sample sizes ranged between 0.5 and 1.5 mg and span 0.1 to 45.1 ka BP (n = 42). A reduced major axis regression shows a strong relationship between GIS and graphite percent Modern Carbon (pMC) values (m = 1.011; 95% CI [0.997–1.023], R2 = 0.999) that is superior to the relationship between the direct carbonate and graphite values (m = 0.978; 95% CI [0.959-0.999], R2 = 0.997). Sixty percent of GIS pMC values are within ±0.5 pMC of their graphite counterparts, compared to 26% of direct carbonate pMC values. The precision of GIS analyses is approximately ±70 14C yrs to 6.5 ka BP and decreases to approximately ±130 14C yrs at 12.5 ka BP. This precision is on par with direct carbonate and is approximately five times larger than for graphite. Six Plio-Pleistocene mollusk and echinoid samples yield finite ages when analyzed as direct carbonate but yield non-finite ages when analyzed as graphite or as GIS. Our results show that GIS 14C dating of biogenic carbonates is preferable to direct carbonate 14C dating and is an efficient alternative to standard graphite 14C dating when the precision of graphite 14C dating is not required.

In 2013, 36 Ancestors of African descent were identified in an unmarked eighteenth-century burial ground during construction in Charleston, South Carolina. The site, later referred to as the Anson Street African Burial Ground, was buried beneath the growing city and forgotten in the centuries that followed. The ethical treatment of these ancestral remains was of paramount importance to our community. Historically, narratives relating to the lives of African descendant people in Charleston have been inadequately documented and shared. For these reasons, we engaged the local African American community in a multifaceted memorialization process. Together, we sought to sensitively ensure that the Ancestors’ identities and lives were fully explored according to the collective descendant community's wishes. To this end, we involved the community in researching and celebrating the Ancestors’ lives through arts and education programs and analyzed their and community members’ DNA to elucidate their ancestry. Our engagement initiatives increased access for all ages to archaeological, historical, and genetic research and encouraged active participation in the design of a permanent memorial. The Anson Street African Burial Ground Project provides a successful example of community-engaged activist archaeology focused on honoring the Ancestors and their descendants.

Determining calendar ages for radiocarbon dates, or ordered sequences of radiocarbon dates, that intersect with a plateau on the radiocarbon calibration curve can be problematic since, without additional prior constraints, the calendar age ranges determined will tend to spread across the plateau, yielding wide and less than useful calendar age probability densities and age ranges. Where possible, modeling analysis should seek to identify informative priors that act to restrict the otherwise poorly controlled spread of probability across plateaus. Such additional information may be available, among other sources, from the stratigraphy, the context, or the samples themselves. The recent dating of ordered sequences of radiocarbon dates on sections of branches of the same olive (Olea europaea) shrub from Therasia (southern Aegean) associated with the Minoan eruption of the Thera (Santorini) volcano (Pearson et al. 2023), which intersect with the plateau in the radiocarbon calibration curve ca. 1620–1540 BC, offers an example of the problem. A re-analysis adding some plausible informative priors offers a substantially better defined likely dating range and different conclusions. Instead of finding an inconclusive probability range “encompassing the late 17th and entire 16th century BC” followed by arguments for “indications of increased probabilities for a mid-16th century BC date for the eruption,” a re-analysis incorporating appropriate informative priors identifies the likely date range as falling between the late 17th to early 16th centuries BC.

This article discusses the absolute chronology of burials from the 3rd and 2nd millennia BC discovered under the mounds of three barrows in the Kordyshiv cemetery in western Ukraine. Its aim is to create a chronological model of the burials by modeling 27 AMS 14C dates obtained from 21 individuals buried in single and collective graves. Dietary analysis of stable carbon (δ13C) and nitrogen (δ15N) isotope values are presented. The Bayesian modeling of the 14C dates from the three Kordyshiv barrows revealed the extremely important role of these monuments as long-term objects used for ritual purposes. At the end of the 3rd millennium BC, the epi-Corded Ware Culture (epi-CWC) community erected a mound over the central burial in Barrow 2, then interred the graves of three additional deceased. After several hundred years Barrow 2 was reused by Komarów Culture (KC) communities from the Middle Bronze Age (MBA) who interred their deceased in the existing mound. The oldest monument with MBA burials was Barrow 3, in which the dead were buried in a two-stage sequence before and after the mid-2nd millennium BC. The youngest dated grave was Burial 1 in Barrow 1, comprising a collective burial that was interred between 1400 and 1200 BC. The additional analyses of carbon and nitrogen isotopes show significant differences in the diet of epi-CWC individuals buried in Barrow 2 from the individuals representing the KC.

Dates from recently excavated Gangetic site of Sakas in Bihar, India, place it at ca.1800–1100 BC. The ceramic and lithic chronologies have been interpreted as Early Farming, Transitional and Chalcolithic/Developed Farming in date. However, depending on where in the Ganges Plains is studied, the time frame of Early, Developed and Advanced Farming periods varies widely, from 7th millennium to 2nd millennium BC and beyond, making the chronological framing of absolute dates within a regional scheme highly complex. In this paper we report the new radiocarbon results from Sakas and note how while these are critical for cementing the absolute dating of the site, until such time as a more stable periodization linked not only to relative and absolute dates but also human lifeways within the different zones of the Ganges plains is created, there remains difficulties in understanding how Sakas and other sites of similar date fit into the changing social, cultural and economic systems in this region.

This article describes a bison rib bone foreshaft from the Blackwater Draw site, New Mexico. The object was recovered by James Hester in 1963, during the excavation of locality 4, and it was subsequently cataloged as a modified bone tool but not recognized as a hafting element. It is currently held in the Blackwater Draw Museum collections. This analysis provides a detailed description of the artifact's features and establishes its provenience from a Folsom context. A survey of known Paleoindigenous hafting implements and a discussion of theoretical Folsom foreshaft designs serve to reinforce the classification of the tool as a component of the Folsom weapon delivery system. The tool was likely broken during use and later recycled as a pressure flaker or as a polishing instrument. With the help of 3D imagery, a reconstructed model was printed and fitted with large and small Folsom points to test ideas borrowed from the theoretical literature on Folsom foreshaft design.

This article presents a systematic literature review of publications from 2014 to 2021 using “archaeological site” and “climate change” as keywords, in addition to several terms representing forms of stakeholder engagement. Articles were thematically coded to explore trends at the intersection of climate change, archaeology, and local and Traditional stakeholders. Results show that nearly half of the selected publications did not include local and Traditional stakeholder engagement in studies related to climate adaptation planning for archaeological sites. Synthesis of the results with insights gained from other literature on decolonizing archaeology showed that potential reasons for this gap include (1) the academic publishing culture, (2) archaeology as a predominantly Western discipline, and (3) increasingly available tools for climate change adaptation planning for archaeological sites. This article calls on the academic community to consider holistic stewardship using a landscape approach and to use climate change adaptation planning to elevate local and Traditional stakeholder input and values.

Paleoethnobotanical remains from basketry and cordage from the Paisley Caves offer an opportunity to explore how people engaged with plant communities over time. Fiber identification of textiles, together with radiocarbon dating, contributes new information about landscape use within the Summer Lake Basin. Expanded marshlands during the terminal Pleistocene / Early Holocene created suitable plant communities ideal for fiber technology, specifically wetland monocots and herbaceous dicots—including dogbane and stinging nettle—by 11,000 years ago. This technology is key to subsistence activities and craft production throughout the Holocene. Despite climatic events during the Middle Holocene, in which people transitioned from caves to sites centered on lakeshores and wetlands, the suite of fiber plants and their technological application remains constant. During the Late Holocene, bast fiber material diversified with the addition of flax and milkweed. The presence of flax in particular, a high-elevation plant, may reflect the increased use of upland root collection areas as populations increased. This research provides long-term data on culturally significant native plants used in the manufacture of fiber-based textiles over the last 14,000 years.

This article explores Indigenous perspectives on archaeology in Canada and the United States and the role of archaeologists in engaging with Indigenous communities. As part of our study, we interviewed Indigenous community members about their experiences in archaeology and their thoughts on the discipline. We analyzed each interview thematically to identify patterns of meaning across the dataset and to develop common themes in the interview transcripts. Based on the results of our analysis, we identified six themes in the data: (1) Euro-colonialism damaged and interrupted Indigenous history, and archaeology offers Indigenous community members an opportunity to reconnect with their past; (2) archaeological practices restrict access of Indigenous community members to archaeological information and archaeological materials; (3) cultural resource management (CRM) is outpacing the capacity of Indigenous communities to engage meaningfully with archaeologists; (4) the codification of archaeology through standards, guidelines, and technical report writing limits the goals of the discipline; (5) archaeological methods are inconsistent and based on individual, or company-wide, funding and decision-making; and (6) archaeological software offers a new opportunity for Indigenous communities and archaeologists to collaborate on projects.

The pressure knapping technique develops circa 25,000 cal BP in Northeast Asia and excels at producing highly standardized microblades. Microblade pressure knapping spreads throughout most of Northeast Asia up to the Russian Arctic, and Alaska, in areas where the human presence was unknown. Swan Point CZ4b is the earliest uncontested evidence of human occupation of Alaska, at around 14,000 cal BP. It yields a pressure microblade component produced with the Yubetsu method, which is widespread in Northeast Asia during the Late Glacial period. Through the techno-functional analysis of 634 lithic pieces from this site, this study seeks to identify the techno-economical purposes for which the Yubetsu method was implemented. Data show that the microblade production system is related to an economy based on the planning of future needs, which is visible through blanks standardization, their overproduction, their functional versatility, and the segmentation of part of the chaîne opératoire. This expresses the efficiency and economic value of the microblade production system. The flexible use of pressure microblades identified at Swan Point CZ4b is also found in Japan, Korea, Kamchatka, and the North Baikal region, suggesting that their modes of use accompany the spread of early microblade pressure knapping over an immense territory across Beringia.