When and why did the modern white hare appear in Siberia?

We present here the information about two representatives of leporine family ((Leporidae) - Don and white hares. The hare remains are common in the deposits of Paleolithic and later human settlements. Siberian materials helped to explain why the Pleistocene Don hare evolved to modern white hare (Lepus timidus). The morphological changes of incisor teeth obviously reflect the evolutional trend. We followed along the massive osteological material obtained in the lower layers of Eleneva Cave deposits near Krasnoyarsk how the radius of incisor teeth reduced gradually. The time span was fixed by 49 th radiocarbon dates range from 13665 to 1050 years. It is expected that the future Lepus timidus were able to reduce the radius of incisor teeth in the course of beneficial mutation and mould into a sort of plyers for effective twig and bark diet. In such a manner they left the “herbivorous niche ”, typical of extinct Don hare. Don hare was described source the Kostenki Paleolithic sites on the banks of Don River 40 years ago. By the final of Late Pleistocene the areal of Don hare included the significant part of northern half in what was then the USSR. He was the biotopical neighbor of the brown hare in the western territories. Author espouses view of the possible evolutional transition L.tanaiticus - L.timidus.