Las faunas de la MN 4 de Aliveri y Karydia (Grecia)

Abstract

The two main small mammal associations from Greece allocated to MN4, Aliveri (island of Evia) and Karydia (Greek Thrace) are discussed here. The age of the locality Aliveri was first thought to be MN3, but there is now general consensus that it represents MN4. This difference in age allocation shows clearly that the use of MN units becomes problematic when we are geographically far from the reference fauna in an area where the local succession of small mammal associations is not known. Detailed studies of the Rodentia and insectivores from Aliveri have shown that the rodents show, except for the presence of eomyids, strong Eastern Mediterranean (Turkish) affinities while the insectivores are similar to the Western European ones. Preliminary studies of the Karydia fauna suggest that this peculiar difference in affinity of the two groups occurs there also. This suggests that migration routes and ecological barriers were different for the two orders. The associations from Aliveri and Karydia share many genera and some species of rodents and are therefore considered to be not very different in age. The insectivores of these localities are similar on the generic level, but the species are not the same. This is unexpected because there is no reason to assume a clear difference in biotope between two sites that have a similar sedimentary environment.