This paper deals with the analysis of changes in the abundance of animals based on about 1500 radiocarbon dates from mammals. The paper is also concerned with the relationship between the representatives of Pleistocene megafauna and other terrestrials that inhabited the Northern hemisphere in the Late Pleistocene-Holocene. Consideration is given to possible causes for the extinction of Proboscidea mammals these causes are briefly commented upon. The main conclusion drawn on the basis of materials included in this study is that the extinction occurred against the background of sudden warming 12–10 thousand years ago, under the probable influence of cosmic and anthropogenic factors. The paper is supplemented with radiocarbon chronologies for Proboscidea mammals that inhabited the Northern hemisphere.