MAGNETOSTRATIGRAPHIC DATA ON THE FIRST COLONIZATION OF EUROPE BY EARLY HOMININS DURING THE LATE EARLY PLEISTOCENE.

It is generally accepted in the paleoanthropological literature that the colonization of Europe by early hominins, intended as Homo erectus derived forms such as Homo heidelbergensis, occurred before the last magnetic polarity reversal that is dated back to 0.78 Ma and marks the transition form the Matuyama reversal polarity chron to the actual normal polarity chron known as Brunhes. The still ongoing debate concerns the possibility for early hominins to have firmly settled in Europe before 1 Million years ago. All the European sites presenting proper chronologies put the first convincing evidence of human occupation during the latter part of the Matuyama reverse polarity chron spanning from the top of Jaramillo normal polarity subchron (0.99 Ma) to the base of the Brunhes normal polarity chron (0.78 Ma). It seems therefore plausible that the first stable human residents came to Europe during the latter part of the Matuyama reverse polarity chron. This relatively brief period of time coincided with a major reorganization of the changing environmental conditions in Europe and elsewhere known as the Early late Pleistocene climate Revolution (EPR). The EPR coincided with the onset of the major Pleistocene glaciation in the Northern hemisphere that triggered the modification of the drainage patterns and consequently brought the formation of the modern fluvial systems especially the Danube in Eastern Europe and the Po in Italy. These environmental changes brought to the formation of new habitats characterized by lowlands colonized by grasslands during glacial/interglacial transitions, while steppic loess environments characterized full glacial periods and closed temperate forests full interglacial periods. The EPR caused also a faunal turnover as a consequence to the environmental changes, species adapted to a closed forest environment belonging to the so-called Villafranchian faunal association were substituted with species more adapted to the newly formed environments belonging to the so-called Galerian faunal association. It seems probable that the opening of the Danube-Po getaway constituted a fundamental element for the migrations of these animals and of early hominins to take place from Africa/Levant across the Balkans into southern Europe since MIS 22. After providing an initial review of the chronology presented for the sites manifesting human occupation of the Mediterranean area we investigated five new sites in order to provide new evidences that will substantiate the hypothesis of the colonization of Europe by early hominins not antecedent the EPR following the Danube-Po migration pathway. The first site is the Arda river section in northern Italy that provides a continuous record of the transition from marine sedimentation typical of the Pliocene-Early Pleistocene to late Early Pleistocene-Holocene continental sedimentation. Even though no human evidences have yet be found in this locality the discovery mammal layer with a mixed Villafranchian-Galerian faunal assemblage just preceding the EPR proves the first contact that occurred between these two faunal associations. The second investigated site is Kostolac, in Serbia, that even thus not revealing any evidence of human occupation, strongly supports the “follow the herd” hypothesis since it yields the first occurrence of the Mammuthus trogontherii in the Pannonian region just before the Brunhes-Matuyama boundary at the bottom of a loessic sequence. This suggests that the first income of this species in the investigated region occurred just after the EPR taking advantage of the Danube-Po gateway. The third presented site is the stratigraphic sequence from the cave of Kozarnika in Northern Bulgaria. Evidences of human occupation of the cave are known throughout the entire stratigraphic sequence as far down as the bottom of the loess deposit that is located between the Jaramillo normal magnetic polarity subchron and the Brunhes normal polarity. The acquired data strongly support the idea that the income of hominins in the investigated region started with MIS 22 along the Danube drainage system from the Black sea into Europe. The fourth investigated site it the Greek site of Megalopolis where an archeological site bearing a specimen of Elephas antiquus with slaughtering evidences lies in an alternation between lignite and sediment levels. The Brunhes-Matuyama boundary lies at the bottom of the sequence but there is no evidence yet of human occupation of the area during the critic time lapse for this study. Strong evidence of the connection between the variation in the deposited facies and the glacial-interglacial cycles was observed therefore we dated the archeological site back to ∼450 ky. The last investigated site is the deposit of the Prince’s cave near Ventimiglia (Northern Italy), where a preneanderthalian human ilium was found in a complex stratigraphic context. Only normal magnetic polarity, interpreted as the Brunhes chron, was observed throughout the entire sequence that was therefore attributed to the middle Pleistocene. Evidences on the oldest units deposited in the cave jointly with the uplift rates for that region suggest that the cave was probably submerged during the EPR and therefore no human frequentation was possible in this site before MIS 7. Except for the Prince’s cave deposit, whose age resulted being to young, all the other sites give evidences of the colonization of Europe by early hominins not antecedent MIS 22 following the Danube-Po migration pathway, therefore supporting the central role of the EPR in the first stable peopling of the European continent.