The article gives the results of author's many years of studies of the paleontological material in the territory of Irkutsk amphitheater. The data on the composition of fossil fauna of the Late Karga period (OIS-3) was obtained from the archaeological and geological cuts of the valley of the Angara river. The considerable diversity of the paleofaunistic associations and intra-species differences was found. Most notable species in this chronology are horse and primitive bison, holding a dominant position. Also it was involved the information about fauna of the Upper Lena river and Lower Tunguska, that differs by their composition and species proportion. It is shown that the trophic Priangariye paleofauna structure is very similar to the trophic of modern African savannah. Based on the radiocarbon dating the procedure of changes in large mammals communities was traced during the Late Karga period and the beginning of the Sartan. Some other materials are presented, helping to reveal the origins of paleofaunistic associations in the Late Karga period.