MIS 3-1 fauna from Krosinko: Implications for the past biogeography, chronology and palaeoenvironments of Poland

摘要

A faunal assemblage was recently recovered from the Krosinko site in Poland, marking a new site in the Warsaw-Berlin ice-marginal valley. Analysis and radiocarbon dating of the remains revealed the presence of two subassemblages: one Late Pleistocene (at least MIS 3-2) and one Holocene (MIS 1), with the former being taxonomically highly diverse. By referring to previous Polish studies, the Pleistocene mammal bone assemblage allowed us to reconstruct the biogeography of its individual components: woolly mammoths, woolly rhinoceri, horses, giant deer, red deer, fallow deer, reindeer, steppe bison, aurochses, bears, and cave lions. The biogeography was later combined with radiocarbon chronology using 21 dates from Krosinko. The wide range of radiocarbon dates (48.4-26.4 ka BP) probably reflects different chronological distributions of species resulting from the changing climate and environment as well as the diverse original sources of the bones. The remains, which constituted a single, compact geological horizon, was possibly deposited in a single geological event around 26 ka BP, as inferred from the most recently produced radiocarbon date. Radiocarbon datings of woolly rhinoceros remains have shown the species to have been present around 38 ka BP, a time that it had previously been considered to have been non-existent in Europe (with no evidence having been discovered for the period 40-34 ka BP). This result alters the stratigraphic gap range for the woolly rhinoceros in Europe to 40-38 ka BP. The clear dominance of woolly mammoth and woolly rhinoceros specimens reflects the structure of the Mam-muthus-Coelodonta faunal complex. The main representatives of this complex preferred the dry and cold conditions that characterized the palaeoenvironmental conditions in Krosinko in MIS 2 and thus in Central Europe, as shown by the integration of the results of the fauna and those of the sediments in which they were deposited. These palaeoenvironmental features are related to the mammoth steppe, which was a long-lived biome in Eurasia and whose diversity influenced the faunal distribution. Thus, the species-by-species review of taxa performed in this paper, against the background of previous results from Poland, illuminates the individual responses of taxa to changing environmental conditions in response to climatic ones. These changes led to the disappearance of the mammoth steppe and near or total extinction of the fauna species inhabiting it.