Acta Zoologica Cracoviensia, 27() 1984
Morphometric variability of dentition of the Late Pleistocene Voles (Arvicolidae, Rodentia) from Bacho Kiro Cave (Bulgaria)
Abstract:
The paper comprises a description of the morphotypical variation in the dentition (chiefly M1) and dimensions of seven arvicolid species. The frequency of particular morphotypes has been calculated and conclusions as to the microevolutionary changes in some species (e.g. Microtus nivalis and Lagurus lagurus) have been drawn. The method of analysis of morphotypes made it possible to treat the specimens described previously under the name of Microtus cf. oeconomus as extreme variants of Microtus nivalis and to include them in this last species. Two forms (M. arvalis and M. agrestis), described earlier as M. arvalis, have also been shown to be present in the fossil materials, although they could not be separated entirely on the basis of either morphology or measurements. In view of the well-established stratigraphy of the locality an analysis and discussion of changes in the length of M1 occurring in particular species from the Early Würm up to the Holocene, have been carried out. These changes were not connected with climatic fluctuations and so they had been brought about by a selective factor other than climatic conditions.
