Late survival of dryopithecine hominoids in Southern Caucasus

Abstract

Dryopithecine hominoids attained an extraordinary diversity during the late middle and early late Miocene (Vallesian) in Europe, including the genera Dryopithecus, Hispanopithecus, Pierolapithecus, Anoiapithecus and Rudapithecus (Agustí et al., 2001a; Alba, 2012). However, after 9.7 Ma, they were decimated and ultimately became extinct in the frame of the so-called Vallesian Crisis (Agustí and Moya-Sol a, 1990; Agustí et al., 2013 ). The Vallesian Crisis, between 9.7 and 8.9 Ma (Garces et al., 1996; Agustí et al., 1997 ), has been explained on the basis of increasing seasonality and spread of deciduous forest (Agustí et al., 2003) and involved the extinction of several of the most common middle Miocene mammalian elements, such as rhinoceroses (Lartetotherium sansaniense, “Dicerorhinus” steinheimensis), suids (Conohyus, Listriodon, Parachleuastochoerus), cervids (Amphiprox, Hispanomeryx), bovids (Protragocerus, Miotragocerus) and carnivores (the barbourofelid Sansanosmilus and the amphicyonids Amphicyon major and Pseudarctos bavaricus). Among the small mammals, the Vallesian Crisis affected several dormice (Eomuscardinus, Myoglis, Bransatoglis, among others), hamsters (Megacricetodon, Eumyarion), flyingsquirrels (Albanensia, Miopetaurista) and beavers (Euroxenomys). The last dryopithecine hominoid (Hispanopithecus laietanus) in Europe is recorded at the late Vallesian site of La Tarumba 1 (Valles- Penedes Basin). This site is placed in a reverse chron identi fied as C4Ar.2r (Garces et al., 1996; Agustí et al., 2001a ), therefore ranging between 9.43 and 9.65 Ma. This is also the case of the Hispanopithecus bearing site of Can Llobateres 2 (Agustí et al., 1996). In Western Europe, only the endemic genus Oreopithecus managed to survive in the Tusco-Sardinian Island, until its connection with the continent at 6.7 Ma (Rook et al., 1999; Alba et al., 2001; Rook et al., 2011; Rook, 2016).