Dynamics of small vertebrate communities from the Pleistocene deposits of the Denisova cave south chamber

The article provides the results of a study of the small vertebrates bone remains collection from the South Chamber of Denisova Cave in Altai Mountains. Faunal materials were collected in 2019 and 2020 during the study of the Pleistocene deposits in the central part of the chamber. In total, more than 30,000 bone remains from lithological layers 19.1-11 were analyzed. The structure of communities was established from 21,489 bones of small vertebrates. Diagnosis of species and genera was made on 19,638 samples. More than 40 species of small mammals were identified, as well as bones of birds, fish, amphibians, and reptiles. Based on the preliminary absolute dating results, lithology, biostratigraphy, and archeology, the layers 19.1-11 deposits were formed in MIS 9 to the first half of MIS 3. The composition of small vertebrates from the Pleistocene deposits of the South Chamber indicates that during the sedimentation of layers 19.1-11 in the Anui River Valley a high mosaic of landscapes was preserved. Light coniferous and dark coniferous forests alternated with meadow, steppe, and desert vegetation. Rock biotopes were constantly preserved. The presence of a number of taxa new to the cave were established. For the first time, the remains of Mus musculus and Ellobius tancrei were found. Some species were shown to have archaic morphological features corresponding to the taxa of the second half of the Middle Pleistocene. A large number of bird egg shells were found. Further study of these materials will allow to clarify the species affiliation of some taxa, the biostratigraphic position of the host deposits, and the natural conditions of their formation.