Timing of the emergence of the Europe–Sicily bridge (40–17 cal ka BP) and its implications for the spread of modern humans

Abstract

The submerged sill in the Strait of Messina, which is located today at a minimum depth of 81 m below sea level (bsl), represents the only land connection between Sicily and mainland Italy (and thus Europe) during the last lowstand when the sea level locally stood at about 126 m bsl. Today, the sea crossing to Sicily, although it is less than 4 km at the narrowest point, faces hazardous sea conditions, made famous by the myth of Scylla and Charybdis. Through a multidisciplinary research project, we document the timing and mode of emergence of this land connection during the last 40 kyr. The integrated analysis takes into consideration morphobathymetric and lithological data, and relative sea-level change (both isostatic and tectonic), resulting in the hypothesis that a continental land bridge lasted for at least 500 years between 21.5 and 20 cal ka BP. The emergence may have occurred over an even longer time span if one allows for seafloor erosion by marine currents that have lowered the seabed since the Last Glacial Maximum (LGM). Modelling of palaeotidal velocities shows that sea crossings when sea level was lower than present would have faced even stronger and more hazardous sea currents than today, supporting the hypothesis that earliest human entry into Sicily most probably took place on foot during the period when the sill emerged as dry land. This hypothesis is compared with an analysis of Pleistocene vertebrate faunas in Sicily and mainland Italy, including a new radiocarbon date on bone collagen of an Equus hydruntinus specimen from Grotta di San Teodoro (23–21 cal ka BP), the dispersal abilities of the various animal species involved, particularly their swimming abilities, and the Palaeolithic archaeological record, all of which support the hypothesis of a relatively late land-based colonization of Sicily by Homo sapiens

Insular mammalian fauna dynamics and paleogeography: A lesson from the Western Mediterranean islands

“…Some hints may come from the analysis of the structure of the diverse faunal complexes: Monte Pellegrino, 'Elephas' falconeri (= Palaeoloxodon falconeri) FC, 'Elephas' mnaidriensis (= Palaeoloxodon mnaidriensis) FC, San Teodoro-Cave Pianetti FC and Castello FC, which succeeded each other during the Pleistocene-early Holocene, showing an increase in biodiversity and a reduction in endemism, which suggest a decrease in the filtering power of barriers that separated the island from southern Italy (Bonfiglio et al 2003Masini et al 2008;Antonioli et al 2016) (Fig. 4).…”

“…From a paleogeographical point of view, the most significant new entry is that of the slender horse E. hydruntinus, a species with extremely reduced swimming ability, which arrived in Sicily thanks to a stable land bridge that temporarily emerged between 21.5 and 20 cal ka BP, as supported by the age of the oldest fossil record of the species thus far known in Sicily (cf. Antonioli et al 2016). Although E. hydruntinus entered Sicily at a later date than the other species, it has to be regarded as a member of the SanTeodoro Cave-Pianetti FC due to its presence in the level BII of San Teodoro cave recording species typical of this FC Mangano 2011).…”

Geology and archaeology: submerged landscapes of the continental shelf: an introduction

“…They include technological advances in the reconstruction of deeply submerged palaeolandscapes and assessment of their archaeological potential (Cawthra et al 2015;Foglini et al 2015;Sakellariou & Galanidou 2015), detailed predictive modelling of the environmental and archaeological potential of submerged landscapes (Ward et al 2014), the discovery, interpretation and wider significance of underwater archaeological sites (Abelli et al 2014;Nutley et al 2014), detailed analysis of shoreline changes and their human impact combining geological, palaeoenvironmental and archaeological evidence (Ryabchuk et al 2014;Galili et al 2015;Kulkova et al 2015), and the effect of sea-level changes on patterns of human dispersal in key areas (Antonioli et al 2014;Glørstad 2014;Wurster & Bird 2014). Glørstad (2014) describes the peopling of Norway following the retreat of the Scandinavian ice sheet.…”

“…However, they are of particular interest in providing an early date for human presence, and in demonstrating the use of methods for detecting and excavating an underwater Stone Age site and its local landscape setting Another key area is the submerged sill in the Strait of Messina, separating Sicily from the Italian mainland, which is located today at a minimum depth of 81 m below sea level. Antonioli et al (2014) provide a detailed analysis of the history of the Strait, integrating information from underwater investigations using bathymetry, geological investigations using ROVs (remotely operated vehicles) and scuba-diving, modelling of eustatic sealevel change, tectonic movements and palaoetidal velocities, and archaeological and palaeontological data. All the evidence points to the emergence of the sill as a land bridge for a period of about 500 years between 21.5 and 20 kyr ago, and radiocarbon dating of palaeontological and archaeological data shows that the earliest human presence on the island coincides with this time interval.…”

Late Quaternary coastal landscape morphology and evolution of the Maltese Islands (Mediterranean Sea) reconstructed from high-resolution seafloor data

“…Antonioli et al 2014). Crucial to better unravelling such a function is the reconstruction of former landscapes that have been inundated by the post-glacial sealevel rise.…”