Preliminary biomarker/paleoclimate reconstruction results from the Marathousa 1 Lower Paleolithic site (Megalopolis basin, Greece)

Abstract

The Marathousa 1 (MAR-1) site is located in central Peloponnese, Greece (Fig. 1A), and was discovered in 2013 as part of a targeted, systematic survey in the Megalopolis Basin by a joint team from the Ephorate of Paleoanthropology and Speleology (Greek Ministry of Culture and Sports) and the Paleoanthropology group of the University of Tübingen (see Panagopoulou et al., 2015, 2018; Harvati et al., 2018). It is one of the few Lower Paleolithic sites in Greece and has been chronologically assigned to the glacial period of Marine Isotope Stage 12 (MIS 12) (Tourloukis et al., 2018b; Jacobs et al., 2018; Blackwell et al., 2018; Bludau et al., 2021). Even if paleoenvironmental suggestions were made by Bludau et al. (2021), the paleoclimatic conditions in the area are not properly constrained yet, making it difficult to assess the MAR-1 evidence in the context of hominin presence in mainland Greece during glacial periods. Here, we perform biomarker analysis to identify changes in the mean air annual temperature (MAAT), paleo-soil pH and organic matter input. Preliminary results from the Marathousa 1 Area B profile (Fig. 1B) indicate major changes affecting southern Greece during the time of hominin presence. Our data show an important cooling episode between ~447 and 444 ka (± 20 ka) (reported dates are based on the age model of Bludau et al., 2021; see Table 1), during the deposition of the clastic sequence, which ends at the stratigraphic level of the archaeological horizon (350.25 cm, Table 1), with mean air annual temperatures as low as 4.5 °C. The lowest registered temperature coinciding with the human presence indicates a direct link between the environmental conditions and the hominin presence in Peloponnese. This evidence supports the hypothesis that the local climatic conditions at Marathousa 1 favored the survival of hominins and other animal species during glacial intervals, acting as a climatic and geographic refugium.