The Rodent Fauna of the Second Half of the Late Holocene in Northeastern European Russia

In this paper we summarize our own and published data on the composition and proportion of rodent remains in fossil assemblages from the second half of the Late Holocene from cave localities in the northeastern part of European Russia as well as rodent assemblages of recent decades based on materials obtained from raptor pellets. It has been established that in the second half of the Late Holocene, the local rodent fauna of the modern taiga zone consisted of forest and intrazonal species in equal proportions, while in the subarctic part, with an insignificant participation of tundra species (up to 8%). In the modern tundra zone (the arctic part of the region), tundra rodent species predominated at that time with a significant participation of forest (up to 33%) and intrazonal species. The presence of tundra species in the Late Holocene local faunas in the north of the taiga zone (the subarctic part of the region) distinguishes them from the modern assemblages, in which only forest and intrazonal species were found, in equal proportions. This feature is probably due to the southward shift of the boundary between tundra and taiga zones during cooling periods in the second half of the Late Holocene.