Introduction
Vindija cave, in northern Croatia, is one of the most significant Palaeolithic and Neanderthal fossil sites in Europe. It is one of nine Palaeolithic sites from the continental and Adriatic regions of Croatia included in the NECEM project (Figures 1 & 2), which began in 2020 and aims to combine multiple lines of research at several sites. Recent excavation and survey—including the measurement of sediment depth via earth resistance tomography and sampling for new dating (radiocarbon and Optically Stimulated Luminescence) and environmental DNA extraction—are complemented by re-analysis of previously excavated lithic material (technology, typology, raw material). The new analyses presented here enhance temporal accuracy for Middle/Upper Palaeolithic hominin activity at both Vindija and in the surrounding region and contribute to our understanding of Neanderthal/early modern human interactions in both regions of Croatia, Central Europe and beyond.
Figure 1. Map showing the location of Vindija Cave and other sites included in the project. Numbers for other sites: 1) Velika pećina (Ravna Gora); 2) Vinica; 3) Campanož; 4) Radovin – Debelo brdo; 5) Velika pećina (Kličevica); 6) Malo polje – Krban; 7) Kaštela bay; 8) Mujina pećina (figure by M. Banda).
Figure 2. Vindija cave (photograph by I. Karavanić).
The project has already produced an analysis of Mousterian lithic materials from Vinica Cave, Malo polje-Krban, Radovin and Velika pećina in Kličevica and a preliminary lithic analysis of the Mousterian open-air site at Campanož (Vukosavljević et al. Reference Vukosavljević, Gužvica, Radanović-Gužvica, Kurtanjek and Karavanić2022; Banda et al. Reference Banda, Romagnoli, Komšo, Čuka and Karavanić2024). Excavation of part of a trench near the cave entrance at Velika pećina in Kličevica and an underwater survey of Kaštela bay have also been conducted (Karavanić et al. Reference Karavanić, Zubčić, Janković, Banda, Sironić and Bronić2021a). Two sites from the continental region, Vindija Cave and Velika pećina (on the Ravna gora)—critical for understanding the demise of Neanderthals and the Middle/Upper Palaeolithic transition in Europe—have been re-dated, as have two Mousterian sites from Dalmatia (Mujina pećina and Velika pećina in Kličevica).
In this article, we present eight new radiocarbon dates from four Vindija faunal samples combining two different techniques of radiocarbon dating—accelerator mass spectrometry (AMS) and accelerator mass spectrometry with collagen ultrafiltration (AMS UF). Two of the samples are from the Mousterian layer G3, which also contains Neanderthal remains, while the other two are from Aurignacian layer F/d, which is attributed to anatomically modern humans.
Dates from these layers enhance the general chronology of a critical period in South-eastern and Central European prehistory. They provide some clarification for the Middle/Upper Palaeolithic interface in Vindija, specifically regarding the large discrepancies in direct dates of Neanderthal remains (see Devièse et al. Reference Devièse2017 and references therein).
Materials and methods
Four faunal bones—originally recovered during excavations in 1974–1986 directed by M. Malez and since curated at the Croatian Academy of Sciences and Arts in Zagreb (the Institute for Quaternary Palaeontology and Geology)—were selected for radiocarbon dating. The two bone fragments from layer G3 belong to ungulates and show traces of modification. The two bone pieces from the Aurignacian layer F/d belong to a canid and an ungulate. Two samples were taken from each bone for radiocarbon dating and two techniques, standard AMS and AMS with UF pre-treatment, were used in parallel to produce dates.
The standard AMS dating was performed at the Ruđer Bošković Institute (RBI). Graphite targets were produced from collagen derived from bone samples (Sironić et al. Reference Sironić, Bronić, Horvatinčić, Barešić, Obelić and Felja2013). The 14C activity measurements on these were provided by the AMS facility of the Center for Applied Isotope Studies at the University of Georgia, USA. Carbon dioxide obtained from the combustion of the collagen was sent to the same institution for δ13C determination by isotope ratio mass spectrometry.
The University of Oxford Radiocarbon Accelerator Unit provided AMS UF dating following standard procedures (Bronk Ramsey et al. Reference Bronk Ramsey, Higham and Leach2004; Brock et al. Reference Brock, Higham, Ditchfield and Ramsey2010). Calibration was performed on radiocarbon dates utilising the OxCal v.4.4.4 (Bronk Ramsey Reference Bronk Ramsey2021) with the IntCal20 calibration curve (Reimer et al. Reference Reimer2020).
Results
The range of δ13C results from both laboratories falls between -18.1 ‰ and -21.9 ‰, values typical for bone collagen (Table 1). Figure 3 shows the calibrated AMS and AMS UF ages for each bone. AMS UF consistently returns older dates and there is no overlap with standard AMS dates. Z-7495 gave an exceptionally young date.
Table 1. Results of radiocarbon dating of bones from Vindija using standard AMS and AMS with UF pre-treatment.
Figure 3. Comparison of calibrated radiocarbon results from Vindija using standard AMS and AMS with UF pre-treatment (1 and 2 sigma error) (figure by I. Krajcar Bronić).
Conclusions
The NECEM project aims to enhance understanding of the temporal aspects of the Middle/Upper Palaeolithic interface in Croatia. Within this project, faunal finds from the late Middle Palaeolithic and early Upper Palaeolithic layers of Vindija cave were dated by standard AMS radiocarbon and UF pre-treatment techniques.
All dates obtained using UF pre-treatment are several thousand years older than standard AMS ages from the same specimens. Results, especially for layer G3, are close to the upper limit of the radiocarbon method. Therefore, we consider the older results (UF pre-treatment) relevant while standard AMS results might only represent minimum ages.
Based on obtained results (UF pre-treatment), the age of the Middle Palaeolithic layer G3 falls between 52 000 and 44 000 cal BP, while the age of early Upper Palaeolithic layer F/d is between 50 000 and 43 000 cal BP (68.3% probability). Results from layer G3 also overlap with direct radiocarbon dates on Neanderthals from G1 (older than approximately 44 000 cal BP), based on amino acid hydroxyproline extraction (Devièse et al. Reference Devièse2017). This apparent chronological overlap between layers G3, G1 and F/d strongly suggests that Neanderthals from Vindija are contemporaries of the earliest modern humans in South-eastern and Central Europe. This is consistent with evidence for the presence of Neanderthals at a potentially even later date in the eastern Adriatic (Karavanić et al. Reference Karavanić, Hellstrom, Rabeder, Vukosavljević, Banda and Smith2021b).
Therefore, new dates obtained from faunal bones from Vindija cave update our understanding of the Middle/Upper Palaeolithic interface at the site and help clarify the chronology of late Neanderthal/early modern human occupations in South-eastern and Central Europe.
Funding statement
The project ‘Last Neanderthals at the Crossroads of Central Europe and the Mediterranean’ (NECEM) is funded by a grant from the Croatian Science Foundation (HRZZ-IP-2019-04-6649).
Data availability statement
All data supporting the conclusions presented are available within the article.
