Ann. Zool. Fennici 51: 27–42 ISSN 0003-455X (print), ISSN 1797-2450 (online) Helsinki 7 April 2014 © Finnish Zoological and Botanical Publishing Board 2014 Late Pleistocene dwarf elephants from the Aegean islands of Kassos and Dilos, Greece Sevket Sen 1, *, Eric Barrier 2 & Xavier Crété 3 1) Laboratoire de Paléontologie du Muséum, CR2P-CNRS-UPMC, 8 rue Buffon, F-75005 Paris, France (*corresponding author’s e-mail: sen@mnhn.fr) 2) iSTeP, Université Paris 6, CNRS, Case 129, 4 Place Jussieu, F-75252 Paris, France 3) 280 Chemin de la Villa des Chênes, F-30250 Aubais, France Received 17June 2013, fnal version received 3 Jan. 2014, accepted 20 Jan. 2014 Sen, S., Barrier, E. & Crété, X. 2014: Late Pleistocene dwarf elephants from the Aegean islands of Kassos and Dilos, Greece. — Ann. Zool. Fennici 51: 27–42. Dwarf elephants are quite well known from the western Mediterranean islands, but they are still poorly documented in most eastern Mediterranean islands. This paper reports on the discovery of a third lower molar of a dwarf elephant from the island of Kassos, which is situated in the southern Aegean, between Crete and Karpathos. This molar is determined as Palaeoloxodon aff. creutzburgi, a dwarfed species known from the Late Pleistocene caves and deposits in Crete and derived from the mainland straight-tusked elephant P. antiquus. An upper molar (M3) from the island of Dilos, previously referred to Elephas antiquus or E. mnaidriensis, is also redescribed. It is almost identical to the upper molars of a paleoloxodontine elephant from Naxos. Its small size and lack of suffcient comparative material lead us to determine it as Palae- oloxodon sp. The palaeogeographic evolution of the Aegean region during the Pleisto- cene and its impact on the dispersal of elephants in the Aegean islands are discussed. Introduction Endemic insular mammals are commonly recorded in Pleistocene deposits and cave infll of Mediterranean islands. They display particu- lar adaptational features and evolutionary trends, different from that of their continental relatives. Elephants, hippos and ruminants (in particular deer) for large mammals, and a few murids and insectivores for small mammals are the main mammalian taxa settled in the Mediter- ranean islands during the Quaternary (Masseti 2009, 2012). They apparently reached islands when particular conditions favored their disper- sal. Azzaroli (1977) hypothesized that terres- trial mammals reached Mediterranean islands through temporary land bridges. Sondaar (1977) proposed another alternative, assuming that the large mammals may have reached islands by swimming and small mammals by passive trans- port on natural rafts. Whatever the way terrestrial mammals used to reach and to populate Mediter- ranean islands, their affnities with mainland mammals indicate palaeobiogeographic relation- ships of islands with the surrounding mainland. The “island rule” in mammals, i.e. impact of island conditions on the trends towards dwarfsm of large mammals and towards gigantism of small mammals, is also an interesting phenom- enon that is largely discussed in the literature