I am very grateful to Antiquity for asking me to read and write a review article of these two volumes. Together they provide an integrated picture of trends in recent years on the themes of mobility and ethnicity in late prehistoric and early historic Europe. Topics, chronology and regional focus are different, if not often opposed, in each book but the reader can easily catch the common ground for further reflection.

‘The collapse c. 1200 BC’ in the Aegean and eastern Mediterranean—which saw the end of the Mycenaean kingdoms, the Hittite state and its empire and the kingdom of Ugarit—has intrigued archaeologists for decades. As Jesse Millek points out in Destruction and its impact, the idea of a swathe of near-synchronous destructions across the eastern Mediterranean is central to the narrative of the Late Bronze Age collapse: “destruction stands as the physical manifestation of the end of the Bronze Age” (p.6). Yet whether there was a single collapse marked by a widespread destruction horizon is up for debate. The two books reviewed here successfully reassess the simplistic and catastrophist characterisation of the end of the Late Bronze Age in the eastern Mediterranean and help provide a more nuanced picture.

Cave carbonate mineral deposits (speleothems) contain trace elements that are intensively investigated for their significance as palaeoclimate and environmental proxies. However, chlorine, which is abundant in marine and meteoric waters, has been overlooked as a potential palaeo-proxy, while cosmogenic 36Cl could, in principle, provide a solar irradiance proxy. Here, total Cl concentrations analysed from various speleothems were low (3–14 mg/kg), with variations linked to crystal fabrics. High-resolution synchrotron radiation micro X-ray fluorescence (μ-XRF) trace element mapping showed Cl often associated with Na, Si, and Al. We propose that speleothems incorporate Cl in two fractions: (1) water soluble (e.g., fluid inclusions) and (2) water insoluble and strongly bound (e.g., associated with detrital particulates). However, disparities indicated that alternate unidentified mechanisms for Cl incorporation were present, raising important questions regarding incorporation of many trace elements into speleothems. Our first measurements of 36Cl/Cl ratios in speleothems required large samples due to low Cl concentrations, limiting the potential of 36Cl as a solar irradiance proxy. Critically, our findings highlight a knowledge gap into how Cl and other trace elements are incorporated into speleothems, how the incorporation mechanisms and final elemental concentrations are related to speleothem fabrics, and the significance this may have for how trace elements in speleothems are interpreted as palaeoclimate proxies.

La costa del Pacífico de los Andes meridionales tiene una larga historia ocupacional que muestra una diversificación regional hacia el Holoceno medio y tardío. La costa del centro norte de Chile tuvo una importante ocupación cazadora-recolectora entre 6000 y 2000 cal aP, que difiere de las observadas en áreas vecinas por sus características ambientales e históricas. Los estudios de contextos funerarios revelan que estos grupos experimentaron una expansión demográfica y vivieron conflictos sociales durante este período. Sin embargo, el énfasis en la importancia de los contextos funerarios entre 6000 y 2000 cal aP ha limitado nuestro conocimiento de las estrategias medioambientales de estos grupos y el uso de los recursos costeros. Esta investigación examina evidencias recuperadas de contextos residenciales y funerarios del sitio Punta Teatinos (Bahía de Coquimbo, costa centro norte de Chile, 29°S) para evaluar las estrategias de uso ambiental aplicadas. El estudio de estas evidencias —incluyendo estratigrafía, fechados radiocarbónicos, material lítico, malacológico y zooarqueológico; microfósiles, cálculos dentales, isótopos estables y arte rupestre— indican una explotación de recursos costeros, a los que se sumaron otros de origen terrestre. Aunque no se identificaron cambios temporales en la explotación de los recursos costeros, las pruebas también indican cambios en la constitución de los paisajes históricos y de las redes sociales extrarregionales.

CH4 is the second most important anthropogenic greenhouse gas and originates from different sources. The use of radiocarbon (14C) analysis of CH4 opens up the possibility to differentiate geological and agricultural origin. At the CologneAMS facility, the demand for 14C analysis of CH4 required the development of a sample handling routine and a vacuum system that converts CH4 to CO2 for direct injection of CO2 into the AMS. We evaluated the processing of CH4 using several series of gas mixtures of 14C-free and modern standards as well as biogas with sample sizes ranging from 10 to 50 µg C. The results revealed a CH4 to CO2 conversion efficiency of 94–97% and blank values comparable to blank values achieved with our routinely used vacuum system for processing CO2 samples. The tests with a near modern CH4:CO2 biogas mixture gave reproducible results with a near modern 14C content of 0.967–1.000 F14C, after applying the background correction.

Although black soil in northeast China undergoes severe erosion, the contribution of parent materials, mainly Quaternary loess and non-loess sediments, to soil erodibility remains unclear. Considering the inheritance of ferromagnetic materials by parent materials, changes in magnetic parameters can successfully determine soil erodibility on a regional scale with a close climatic background. Here, we analysed the magnetic indicators of 142 samples from the black soil horizon formed on loess and non-loess sediments, covering areas of severe and slight erosion in the region to determine the effects of parent materials on the erodibility of black soil in northeast China. Both low-frequency magnetic susceptibility and frequency magnetic susceptibility (χfd) were proportional to the decrease in erosion rate due to erosion-induced leaching of ferromagnetic materials, and the change in χfd was narrow for black soil with loess parent materials, corresponding to relatively low soil erodibility. Compared with loess, the addition of soil organic matter could stabilise soils against erosion, thereby inducing a decrease in the erodibility of black soil formed on loess. Additionally, sustainable soil management policies to protect black soil from further erosion are necessary and urgent under the pressure of maintaining high grain yields and preventing erosion in northeast China.

This article presents radiocarbon dates on 29 perishable objects deposited in shrine caves in the Jornada and Mimbres Mogollon regions of far west Texas and southern New Mexico. The dated objects include tablita fragments, effigies, prayer sticks, hafted projectile point foreshafts, and flat curved sticks. Analysis of the dates reveals three significant trends: a particular set of Indigenous ritual practices involving shrine caves in the North American Southwest was of extraordinary temporal depth and continuity; the meanings and material culture associated with shrine caves changed through time; and a signature iconographic expression of Jornada and Mimbres origin cosmologies, the Goggle-eye or “Tlaloc” entity, is older than previously understood. The dating of shrine caves and iconographic motifs provides new insights on early eras of religious expression in the southern Southwest, clarifying both the nature and time depth of foundational cosmologies and providing a deep time perspective for interpretations of how such cosmologies and their material and iconographic expressions changed through time.

Developments in radiocarbon dating and analysis provide new opportunities to develop high-resolution chronologies to explore changes through time. We explore the temporality of what has been called the Poverty Point culture of the lower Mississippi Valley circa 4200 to 3200 cal BP, especially the chronology of the type site, Poverty Point. Because of its complicated material culture elaboration without evidence of agriculture, Poverty Point has been identified as the political and economic center of a complex archaeological culture. The duration of site occupation and the historical relationship between the type site and those assumed to be contemporary are critical variables for explaining the emergence of complexity at this time. Most interpretations require political or evolutionary processes that accumulate gradually over hundreds of years. Our data show, however, that there is no temporal coherence among so-called Poverty Point culture sites; among such sites, Poverty Point was occupied for a relatively short period, and it is younger than many sites thought to be derived from it. Using explicit radiometric hygiene and Bayesian analyses of dates, we reject the idea of a unified Poverty Point culture and argue instead that the Poverty Point site earthworks developed through rapid, punctuated events occurring circa 3300 to 3200 cal BP.

Radiocarbon data are the most commonly used chronometric measurement technique in archaeology. The introduction of the radiocarbon method offered new potential for independent, internationalized research projects. Today millions of radiocarbon measurements exist globally. However, the many strengths of radiocarbon for research in archaeology have also created an internationally significant challenge in heritage practice. How can we attempt to curate huge volumes of radiocarbon “legacy” data in systematic ways that facilitate interdisciplinary, international research? How can we contend with a dataset that is rapidly scalable, and needs to be kept live—updated, validated, curated, and related to existing national archives and data systems—beyond the timescale of any individual project? In this paper we introduce an international project, “Project Radiocarbon; Big Data, integrated cross-national heritage histories”, working across the historic environment sector in Ireland and the United Kingdom, that is developing a solution to these issues. We argue that we need to think critically about how we classify and curate radiocarbon data, to render them interoperable and findable. Such work requires inter-sector approaches to ensure sustainability and scalability, and to anticipate the increasing value of these data into the future.