Chronometric data and stratigraphic evidence support discontinuity between Neanderthals and early Homo sapiens in the Italian Peninsula.

The process by which Palaeolithic Europe was transformed from a Neanderthal-dominated region to one occupied exclusively by Homo sapiens has proven challenging to diagnose. A blurred chronology has made it difficult to determine when Neanderthals disappeared and whether modern humans overlapped with them. Italy is a crucial region because here we can identify not only Late Mousterian industries, assumed to be associated with Neanderthals, but also early Upper Palaeolithic industries linked with the appearance of early H. sapiens, such as the Uluzzian and the Aurignacian. Here, we present a chronometric dataset of 105 new determinations (74 radiocarbon and 31 luminescence ages) from four key southern Italian sites: Cavallo, Castelcivita, Cala, and Oscurusciuto. We built Bayesian-based chronometric models incorporating these results alongside the relative stratigraphic sequences at each site. The results suggest; 1) that the disappearance of Neanderthals probably pre-dated the appearance of early modern humans in the region and; 2) that there was a partial overlap in the chronology of the Uluzzian and Protoaurignacian, suggesting that these industries may have been produced by different human groups in Europe.

Multi-method dating reveals 200 ka of Middle Palaeolithic occupation at Maras rock shelter, Rhône Valley, France.

The emergence of the Middle Palaeolithic, and its variability over time and space are key questions in the field of prehistoric archaeology. Many sites have been documented in the south-eastern margins of the Massif central and the middle Rhône valley, a migration path that connects Northern Europe with the Mediterranean. Well-dated, long stratigraphic sequences are essential to understand Neanderthals dynamics and demise, and potential interactions with Homo sapiens in the area, such as the one displayed at the Maras rock shelter ("Abri du Maras"). The site is characterised by exceptional preservation of archaeological remains, including bones dated using radiocarbon (14C) and teeth using electron spin resonance combined with uranium series (ESR/U-series). Optically stimulated luminescence was used to date the sedimentary deposits. By combining the new ages with previous ones using Bayesian modelling, we are able to clarify the occupation time over a period spanning 200,000 years. Between ca. 250 and 40 ka, the site has been used as a long-term residence by Neanderthals, specifically during three interglacial periods: first during marine isotopic stage (MIS) 7, between 247 ± 34 and 223 ± 33 ka, and then recurrently during MIS 5 (between 127 ± 17 and 90 ± 9 ka) and MIS 3 (up to 39,280 cal BP).

Alternatives to 137Cs for 210Pb dating validation in south America and in the Carribean region: Point and diffuse sources.

As today the 137Cs fallout peak, in sediment cores, corresponds only to 25% of its initial concentration, alternatives to the use of 137Cs as a210Pb sediment dating validation tool are proposed. In highly industrialized bays, such as Guanabara Bay in the Rio de Janeiro metropolitan region, several chemical/compounds from the surrounding industry releases may be applied as validation tools. Chromium and copper profiles in a sediment core adequately fit the expected pattern due to the implementation of a chemical plant in 1958, reaching their maximum discharge in 1982 and subsequently decreasing due to the operation of a new wastewater treatment plant. A diffuse source such, as the PCB-based mixture Askarel, was also applied as an alternative validation tool, and the observed concentration profile reproduced the expected behavior, with increasing concentration after the Second World War and a decrease after the ban of this product in 1981. The observed Aroclor 1254 and 1260 mixture chlorination rates fit the most widely distributed PCB-based products in the country.

Demystifying the tropics: FTIR characterization of pantropical woods and their α-cellulose extracts for past atmospheric 14C reconstructions.

To ensure unbiased tree-ring radiocarbon (14C) results, traditional pretreatments carefully isolate wood cellulose from extractives using organic solvents, among other chemicals. The addition of solvents is laborious, time-consuming, and can increase the risk of carbon contamination. Tropical woods show a high diversity in wood-anatomical and extractive composition, but the necessity of organic-solvent extraction for the 14C dating of these diverse woods remains untested. We applied a chemical treatment that excludes the solvent step on the wood of 8 tropical tree species sampled in South-America and Africa, with different wood-anatomical and extractive properties. We analyzed the success of the extractive removal along with several steps of the α-cellulose extraction procedure using Fourier Transform Infrared (FTIR) spectroscopy and further confirmed the quality of 14C measurements after extraction. The α-cellulose extracts obtained here showed FTIR-spectra free of signals from various extractives and the 14C results on these samples showed reliable results. The chemical method evaluated reduces the technical complexity required to prepare α-cellulose samples for 14C dating, and therefore can bolster global atmospheric 14C applications, especially in the tropics.

A revised radiocarbon calibration curve 350-250 BCE impacts high-precision dating of the Kyrenia Ship.

The Kyrenia Ship, found off the north coast of Cyprus, is a key vessel in the history of scientific underwater excavations and in the history of Greek shipbuilding. The first volume of the site's final publication appeared in 2023 and provides detailed archaeological information tightly constraining the dating of the ship. A very specific date range is proposed: ca. 294-290 BCE, but is based on a less than certain reading of one coin recovered from the ship. While there is clear benefit to finding high-precision dates for the Kyrenia Ship and its rich assemblage using independent scientific dating (combined with Bayesian chronological modeling), efforts to do so proved more challenging and complex than initially anticipated. Strikingly, extensive radiocarbon dating on both wooden materials from the ship and on short-lived contents from the final use of the ship fail to offer dates using the IntCal20 calibration curve-the current Northern Hemisphere radiocarbon calibration curve at the time of writing-that correspond with the archaeological constraints. The issue rests with a segment of IntCal20 ca. 350-250 BCE reliant on legacy pre-AMS radiocarbon data. We therefore measured new known-age tree-ring samples 350-250 BCE, and, integrating another series of new known-age tree-ring data, we obtained a redefined and more accurate calibration record for the period 433-250 BCE. These new data permit a satisfactory dating solution for the ship and may even indicate a date that is a (very) few years more recent than current estimations. These new data in addition confirm and only very slightly modify the dating recently published for the Mazotos ship, another Greek merchant ship from the southern coast of Cyprus. Our work further investigated whether ship wood samples impregnated with a common preservative, polyethylene glycol (PEG), can be cleaned successfully, including a known-age test.

Archaeobotanical evidence supports indigenous cucurbit long-term use in the Mesoamerican Neotropics.

The squash family (Cucurbitaceae) contains some of the most important crops cultivated worldwide and has played an important ecological, economic, and cultural role for millennia. In the American tropics, squashes were among the first cultivated crop species, but little is known about how their domestication unfolded. Here, we employ direct radiocarbon dating and morphological analyses of desiccated cucurbit seeds, rinds, and stems from El Gigante Rockshelter in Honduras to reconstruct human practices of selection and cultivation of Lagenaria siceraria, Cucurbita pepo, and Cucurbita moschata. Direct radiocarbon dating indicates that humans started using Lagenaria and wild Cucurbita starting ~ 10,950 calendar years before present (cal B.P.), primarily as watertight vessels and possibly as cooking and drinking containers. A rind directly dated to 11,150-10,765 cal B.P. represents the oldest known bottle gourd in the Americas. Domesticated C. moschata subsequently appeared ~ 4035 cal B.P., followed by domesticated C. pepo ~ 2190 cal B.P. associated with increasing evidence for their use as food crops. Multivariate statistical analysis of seed size and shape show that the archaeological C. pepo assemblage exhibits significant variability, representing at least three varieties: one similar to present-day zucchini, another like present-day vegetable marrow, and a native cultivar without modern analogs. Our archaeobotanical data supports the hypothesis that Indigenous cucurbit use started in the Early Holocene, and that agricultural complexity during the Late Holocene involved selective breeding that encouraged crop diversification.

Dividing time-An absolute chronological study of material culture from Early Iron Age urnfields in Denmark.

Chronological frameworks based on artefact typologies are essential for interpreting the archaeological record, but they inadvertently treat transitions between phases as abrupt events and disregard the temporality of transformation processes within and between individual phases. This study presents an absolute chronological investigation of a dynamic material culture from Early Iron Age urnfields in Denmark. The chronological framework of Early Iron Age in Southern Scandinavia is largely unconstrained by absolute dating, primarily due to it coinciding with the so-called 'Hallstatt calibration plateau' (c.750 to 400 cal BC), and it is difficult to correlate it with Central European chronologies due to a lack of imported artefacts. This study applies recent methodological advances in radiocarbon dating and Bayesian chronological modelling, specifically a statistical model for wood-age offsets in cremated bone and presents the first large-scale radiocarbon investigation of regional material culture from Early Iron Age in Southern Jutland, Denmark. Dated material is primarily cremated bone from 111 cremation burials from three urnfields. The study presents absolute date ranges for 16 types of pottery and 15 types of metalwork, which include most of the recognised metalwork types from the period. This provides new insights into gradual change in material culture, when certain artefact types were in production and primary use, how quickly types were taken up and later abandoned, and distinguishing periods of faster and slower change. The study also provides the first absolute chronology for the period, enabling correlation with chronologies from other regions. Urnfields were introduced at the Bronze-Iron Age transformation, which is often assumed to have occurred c.530-500 BC. We demonstrate that this transformation took place in the 7th century BC, however, which revives the discussion of whether the final Bronze Age period VI should be interpreted as a transitional phase to the Iron Age.

Puzzling parrotfishes: Radiocarbon age validation and updated longevity estimates for western Atlantic species in support of sustainable fisheries management.

For management efforts to succeed in Caribbean fisheries, local fishers must support and be willing to comply with fishing regulations. This is more likely when fishers are included in a stock assessment process that utilizes robust scientific evidence, collected in collaboration with fishers, to evaluate the health of fish stocks. Caribbean parrotfishes are important contributors to coral reef ecosystem health while also contributing to local fisheries. Scientifically robust stock assessments require regional species-specific information on age-based key life history parameters, derived from fish age estimates. Evaluation of the accuracy of age estimation methods for fish species is a critical initial step in managing species for long-term sustainable harvest. The current study resulted from a collaborative research program between fish biologists and local fishers investigating age, growth, and reproductive biology of the seven parrotfish species landed in U.S. Caribbean fisheries; specifically, we validated age estimation for stoplight parrotfish Sparisoma viride and queen parrotfish Scarus vetula. This is the first study to directly validate age estimation for any parrotfish species through analysis of Δ14C from eye lens cores. Our age estimation validation results show that enumeration of opaque zones from thin sections of sagittal otoliths for a Sparisoma and a Scarus species provides accurate age estimates. The oldest stoplight parrotfish and queen parrotfish in the Δ14C age estimation validation series were 14 y and 16 y; while the oldest stoplight parrotfish and queen parrotfish we aged to-date using the Δ14C validated age estimation method were 20 y and 21 y, respectively. Fish longevity (maximum age attained/life span) is a key life history parameter used for estimation of natural mortality, survivorship, and lifetime reproductive output. Past reviews on parrotfishes from the Pacific and Atlantic concluded that most Caribbean/western Atlantic parrotfish species are relatively short-lived with estimated maximum ages ranging from 3-9 y. However, information from our collaborative research in the U.S. Caribbean combined with recently published age estimates for Brazilian parrotfish species indicate that many western Atlantic parrotfishes are relatively long-lived with several species attaining maximum ages in excess of 20 y.

Life histories in Fiji as reconstructed from first millennium CE Sigatoka Sand Dune burials using isotopes.

This paper aims to re-examine the dietary practices of individuals buried at Sigatoka Sand Dunes site (Fiji) in Burial Ground 1 excavated by Simon Best in 1987 and 1988 using two approaches and a reassessment of their archaeological, bioarchaeological and chronological frame. First, stable carbon and nitrogen isotope analysis was applied to document dietary changes between childhood and adulthood using an intra-individual approach on paired bone-tooth. Second, the potential adaptation of the individuals to their environment was evaluated through regional and temporal comparisons using inter-individual bone analysis. Ten AMS radiocarbon dates were measured directly on human bone collagen samples, placing the series in a range of approximately 600 years covering the middle of the first millennium CE (1,888 to 1,272 cal BP). δ13C and δ15N ratios were measured on bone and tooth collagen samples from 38 adult individuals. The results show that δ15N values from tooth are higher than those s from bone while bone and tooth δ13C values are similar, except for females. Fifteen individuals were included in an intra-individual analysis based on paired bone and tooth samples, which revealed six dietary patterns distinguished by a differential dietary intake of marine resources and resources at different trophic levels. These highlight sex-specific differences not related to mortuary practices but to daily life activities, supporting the hypothesis of a sexual division of labour. Compared to other Southwest Pacific series, Sigatoka diets show a specific trend towards marine food consumption that supports the hypothesis of a relative food self-sufficiency requiring no interactions with other groups.

Identification and tentative removal of collagen glue in Palaeolithic worked bone objects: implications for ZooMS and radiocarbon dating.

Collagen glue has been used for nearly two centuries to consolidate bone material, although its prevalence in museum collections is only now becoming visible. Identifying and removing collagen glue is crucial before the execution of any geochemical or molecular analyses. Palaeolithic bone objects from old excavations intended for radiocarbon dating were first analysed using ZooMS (Zooarchaeology by Mass Spectrometry) to identify the animal species, however peaks characteristic of both cattle and whale were discovered. Two extraction methods for ZooMS were tested to identify the authentic animal species of these objects, which revealed that these were originally whale bone objects that had been consolidated with cattle collagen glue. This is the first time animal collagen glue has been identified in archaeological remains with ZooMS, illustrating again the incredible versatility of this technique. Another technique, Fourier Transform Infrared Spectroscopy in Attenuated Total Reflectance mode (FTIR-ATR), was also tested if it could rapidly identify the presence of collagen glue in archaeological bone material, which was not the case. Two other cleaning methods were tested to remove bone glue contamination prior to radiocarbon dating, along with two modified collagen extraction methods for ZooMS. These methods were applied to bone blank samples (FmC = 0.0031 ± 0.0002, (n = 219), 47 336 ± 277 yr BP) that were experimentally consolidated with collagen glue and to the Palaeolithic bone material (ca. 15 000 and 12 000 yr BP). The experimental bone blanks produced excellent 14C ages, suggesting the cleaning methods were successful, however the 14C ages for some of the Palaeolithic material remained too young considering their contextual age, suggesting that the collagen glue contamination had most likely cross-linked to the authentic collagen molecule. More research is needed in order to gain a deeper understanding of the occurrence and elimination of cross-linked collagen-based glues in material from museum collections.

The chronology of Gezer from the end of the late bronze age to iron age II: A meeting point for radiocarbon, archaeology egyptology and the Bible.

The ancient southern Levantine city of Gezer is well-known from Egyptian, Biblical and Assyrian sources, associated with power struggles, conquests, and intriguing tales involving figures such as Milkilu and Amenhotep III, Merneptah, the Philistines, Solomon and his unidentified pharaonic father-in-law, and Shishak / Sheshonq I. Since the identity of Gezer with "Tell Jezer" is quite literally 'set in stone' by some dozen boundary inscriptions, along with impressive Bronze and Iron Age remains, research at this site provides a unique opportunity to compare text and archaeology, as well as bring to light the undocumented everyday lives of the city's inhabitants. In this endeavour, independent scientific dating is crucial for anchoring the remains chronologically. This paper presents the first substantial radiocarbon dataset and Bayesian chronological analysis for Gezer spanning the last part of the Late Bronze Age (LBA; LB IIB) through Iron Age II. The dataset derives from an essentially continuous stratigraphic sequence exposed in recent years by the Tandy expedition along the central-southern edge of the site. The results allow us for the first time to independently determine the site chronology, test the viability (from a chronological perspective) of proposed historical correlations, and contribute to debates on Philistine and Iron Age chronology.

Independent age estimates resolve the controversy of ancient human footprints at White Sands.

Human footprints at White Sands National Park, New Mexico, USA, reportedly date to between ~23,000 and 21,000 years ago according to radiocarbon dating of seeds from the aquatic plant Ruppia cirrhosa. These ages remain controversial because of potential old carbon reservoir effects that could compromise their accuracy. We present new calibrated 14C ages of terrestrial pollen collected from the same stratigraphic horizons as those of the Ruppia seeds, along with optically stimulated luminescence ages of sediments from within the human footprint-bearing sequence, to evaluate the veracity of the seed ages. The results show that the chronologic framework originally established for the White Sands footprints is robust and reaffirm that humans were present in North America during the Last Glacial Maximum.

Radiocarbon dating as tool to assist in triaging cases of unidentified human remains in Victoria, Australia: A case series.

In cases where human remains are unidentified because there is no initial identification hypothesis, limited contextual information, and/or poor preservation, radiocarbon (14 C) dating may be a useful tool to further assist with identification. Through measuring the amount of 14 C remaining in organic material, such as bone, teeth, nail, or hair, radiocarbon dating may provide an estimated year of birth and year of death for a deceased person. This information, may assist in, establishing whether a case of unidentified human remains (UHR) is actually of medicolegal significance and therefore, requires forensic investigation and identification. This case series highlights the application of 14 C dating to seven of the 132 UHR cases in Victoria, Australia. Cortical bone was sampled from each case and the level of 14 C was measured to provide an estimated year of death. Four of the seven cases analyzed contained the levels of 14 C consistent with an archeological timeframe, one contained a level of 14 C consistent with a modern (i.e., of medicolegal significance) timeframe, and the results for the remaining two samples were inconclusive. Applying this technique not only reduced the number of UHR cases in Victoria but also has investigative, cultural, and practical implications for medicolegal casework in general.

Back to the future: The advantage of studying key events in human evolution using a new high resolution radiocarbon method.

Radiocarbon dating is the most widely applied dating method in archaeology, especially in human evolution studies, where it is used to determine the chronology of key events, such as the replacement of Neanderthals by modern humans in Europe. However, the method does not always provide precise and accurate enough ages to understand the important processes of human evolution. Here we review the newest method developments in radiocarbon dating ('Radiocarbon 3.0'), which can lead us to much better chronologies and understanding of the major events in recent human evolution. As an example, we apply these new methods to discuss the dating of the important Palaeolithic site of Bacho Kiro (Bulgaria).

Dating the Paleolithic: Trapped charge methods and amino acid geochronology.

Despite the vast array of different geochronological tools available, dating the Paleolithic remains one of the discipline's greatest challenges. This review focuses on two different dating approaches: trapped charge and amino acid geochronology. While differing in their fundamental principles, both exploit time-dependent changes in signals found within crystals to generate a chronology for the material dated and hence, the associated deposits. Within each method, there is a diverse range of signals that can be analyzed, each covering different time ranges, applicable to different materials and suitable for different paleoenvironmental and archaeological contexts. This multiplicity of signals can at first sight appear confusing, but it is a fundamental strength of the techniques, allowing internal checks for consistency and providing more information than simply a chronology. For each technique, we present an overview of the basis for the time-dependent signals and the types of material that can be analyzed, with examples of their archaeological application, as well as their future potential.

The Monongahela tradition in "real time": Bayesian analysis of radiocarbon dates.

Despite advances in techniques, methods, and theory, northeastern North American archaeologists continue to use early to mid-twentieth century culture historical taxa as units of analysis and narrative. There is a distinct need to move away from this archaeological practice to enable fuller understandings of past human lives. One tool that enables such a move is Bayesian analysis of radiocarbon dates, which provides a means of constructing continuous chronologies. A large dataset of radiocarbon dates for late prehistoric (ca AD 900/1000-1650) sites in the lower upper Ohio River basin in southwestern Pennsylvania and adjacent portions of Maryland, Ohio, and West Virginia is used here as an example. The results allow a preliminary assessment of how the settlement plans of contemporaneous villages varied considerably, reflecting decisions of the village occupants how to structure built environments to meet their needs.

Temporal population structure, a genetic dating method for ancient Eurasian genomes from the past 10,000 years.

Radiocarbon dating is the gold standard in archeology to estimate the age of skeletons, a key to studying their origins. Many published ancient genomes lack reliable and direct dates, which results in obscure and contradictory reports. We developed the temporal population structure (TPS), a DNA-based dating method for genomes ranging from the Late Mesolithic to today, and applied it to 3,591 ancient and 1,307 modern Eurasians. TPS predictions aligned with the known dates and correctly accounted for kin relationships. TPS dating of poorly dated Eurasian samples resolved conflicting reports in the literature, as illustrated by one test case. We also demonstrated how TPS improved the ability to study phenotypic traits over time. TPS can be used when radiocarbon dating is unfeasible or uncertain or to develop alternative hypotheses for samples younger than 10,000 years ago, a limitation that may be resolved over time as ancient data accumulate.

A Tibetan ice core covering the past 1,300 years radiometrically dated with 39Ar.

Ice cores from alpine glaciers are unique archives of past global and regional climate conditions. However, recovering climate records from these ice cores is often hindered by the lack of a reliable chronology, especially in the age range of 100 to 500 anni (a) for which radiometric dating has not been available so far. We report on radiometric 39Ar dating of an ice core from the Tibetan Plateau and the construction of a chronology covering the past 1,300 a using the obtained 39Ar ages. This is made possible by advances in the analysis of 39Ar using the laser-based detection method atom trap trace analysis, resulting in a twofold increase in the upper age limit of 39Ar dating. By measuring the anthropogenic 85Kr along with 39Ar we quantify and correct modern air contamination, thus removing a major systematic uncertainty of 39Ar dating. Moreover, the 85Kr data for the top part of the ice core provide information on firn processes, including the age difference between the ice and its enclosed gas. This first application of 39Ar and 85Kr to an ice core facilitates further ice cores from nonpolar glaciers to be used for recovering climate records of the Common Era, a period including pronounced anomalies such as the Little Ice Age and the Medieval Warm Period.

RADIOCARBON DATING OF CHARCOALS FROM HISTORICAL MORTARS FROM TÝROV AND PYSOLEC CASTLES.

Organic inclusions in lime binders provide useful samples for radiocarbon dating of historical objects. Two Czech castles Týrov and Pysolec from Late Middle Ages were explored, and tens of charcoals were found in their walls. The radiocarbon content of the charcoals was measured with accelerator mass spectrometry. The dating results showed that none of the charcoals were younger than the known historical ages (Týrov: 1260 - 1270, Pysolec: 1300 - 1340), but some were considerably older. Two charcoals from Pysolec castle dated to Palaeolithic, likely originating from fluvial sediments added as an aggregate to the mortar. When excluding these two charcoals, the others indicated most likely dates being 50-100 y older than the building dates of the castles. This systemic effect corresponds to the age of wood used for lime burning and shall be accounted for when dating mortars using charcoals.

A refined chronology for the Middle and early Upper Paleolithic sequence of Riparo Mochi (Liguria, Italy).

The Riparo Mochi rock shelter, located on the Ligurian coast of Italy, is one of the most important early Upper Paleolithic sites on the Mediterranean rim. Its ∼10-m-deep stratigraphy comprises a Mousterian sequence, followed by various development stages of the Upper Paleolithic. A series of radiometric dates on marine shells bearing traces of human modification has provided a chronological framework for the final Mousterian and the Proto-Aurignacian of the site. Based on modeling results, the end of the Mousterian was dated between 44.0 and 41.8 ka cal BP (68% probability) and the beginning of the Proto-Aurignacian between 42.7 and 41.6 ka cal BP (68% probability). However, these estimates were based on a limited number of radiocarbon ages in the Mousterian levels. Here, we report new dating of the Mochi sequence using luminescence techniques, along with new radiocarbon measurements. The combination of these results using a Bayesian modeling approach allows for the first time the establishment of a more precise timing for the Mousterian occupation at the site. We show that Mousterian groups were already present at Riparo Mochi by at least 65 ka and continued to occupy the site for another 20 ka. The transition to the earliest Upper Paleolithic at the site is centered around 44.3-41.1 ka (95.4% probability), providing our best age estimate for the beginning of the Early Upper Paleolithic and the establishment of modern human groups in the Balzi Rossi. The sequence continues upward with a more evolved Aurignacian phase and a Gravettian phase starting at ∼26 ka or earlier.