Environment and climate of the Crimean Mountains during the Late Pleistocene inferred from stable isotope analysis of red deer (Cervus elaphus) bones from the Emine-Bair-Khosar Cave

Abstract

The Crimean Peninsula is an extraordinary region located on the border between Europe and Asia. Its location made it an important refuge for migratory animals during the entire Pleistocene. The red deer (Cervus elaphus) was one of the most abundant species among large herbivores in the Crimean region. Its numerous remains were found in several cave sites, including the Emine-Bair-Khosar Cave. The bone-bearing sediments in the cave were deposited from MIS 3 to the beginning of the Holocene, with a significant hiatus during the Last Glacial Maximum (LGM). These two facts made it possible to reconstruct the climate changes and plant succession during the last 40,000 years. To recognise these processes, we studied the isotopic composition of carbon and nitrogen of collagen from red deer bones deposited in this trap cave. At the beginning, the δ15Ncoll values varied widely, suggesting a relatively high proportion of grass in the red deer diet. The high 15N concentrations were correlated with relatively high δ13Ccoll values. This part of the sequence was probably deposited during a relatively warm and dry period (MIS 3) when steppe was the dominant vegetation type. Later, the δ15Ncoll values decreased significantly and the δ13Ccoll remained basically unchanged. The prominent decrease in the soil activity suggests a climate deterioration and tundra development during MIS 2, before the Last Glacial Maximum (LGM). After LGM, during the Late Glacial, the δ13Ccoll declined and the δ15Ncoll significantly increased, reflecting milder climate conditions and, probably, spread of forest near the cave.