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Both pliopithecoid and hominoid primates were widely distributed throughout Eurasia during the Miocene but are known to have coexisted at only a few localities. It has been speculated that their different habitat preferences permitted only minimal overlap under special environmental conditions. Here we study the context for pliopithecoid and hominoid co-occurrence by assessing taxonomically-based palaeoecological diversity of associated fossil mammals and by direct ecometric analysis based on hypsodonty of mammalian herbivores. Our results show that pliopithecoids persistently inhabited more humid environments compared to the other primate groups studied, suggesting an inability to adapt to changing environmental conditions. The opportunity for hominoids and pliopithecoids to co-occur appears to have been restricted by niche conservatism in the latter group. Our study also indicates that direct ecometric analysis gives a better separation of the ecological preferences of these primate clades than do analyses of taxonomically-based community structure.

Rhinocerotid remains from the middle Miocene Anatolian locality at Pasalar are described, and referred to Begertherium tekkayai, Aceratherium sp. aff. tetradactylum, and Brachypotherium brachypus. Begertherium tekkayai (= Beliajevina tekkayai HEISSIG) is only known from this locality. The material of Brachypotherium brachypus is similar to that from Sansan and Steinheim am Albuch (MN6–7), rather than to the earlier (informal) species B. stehlini known from La Romieu and Baigneaux (MN4), or to described African and Asian species. Begertherium tekkayai was probably a grazer, Aceratherium sp. a browser and Brachypotherium brachypus a mixed feeder. The very high proportion of juveniles in the Begertherium sample may point to accumulation by a predator.

The Pasalar fauna is found to include four suoid species including two listriodont pigs, Listriodon ef. splendens and Listriodon sp. nov., a tetraconodont, Conohyus simorrensis (sensu lato) and a peccary, Taucanamo inonuensis. This assemblage of folivores and “omnivores” presumably veflects the presence of relatively lush vegetation in the area. The cooccurrence of a derived sublophodont listriodont, Listriodon sp. nov., of roughly similar evolutionary grade to the late early Miocene European species Listriodon lockharti (from MN 4b and 5 localities of Europe) with the lophodont form Listriodon ef. splendens (MN 6-MN 9 localities of Europe suggests that the Pasalar fauna is referrable to MN 6, ea. 15 Ma, or possibly somewhat younger. While the Pasalar suoid assemblage shows broad Eurasian affinities, Listriodon sp. nov. and Taucanamo inonuensis provide evidence for a certain degree of endemism. We hypothesize here that this endemism developed after the late Burdigalian marine regression (ca. 17 Ma, and taken here as being chronologically equivalent to MN4b and lower MN 5), which promoted active Eurasian and African faunal exchanges.

A tubulidentate, a chalicothere and a hyracoid from Pasalar (middle Miocene of Western Anatolia) are described. The tubulidentate is referred to Orycteropus sp. The chalicothere is new to the site, and is referred to Chalicothere grande. Pliohyrax graecus was described from Pasalar by Hunermann 1985, based on material that probably does not come from this site. The new hyracoid remains are referred to Pliohyracidae incertae sedis. Coexistence of these forms might indicate a forest-woodland mosaic environment. There is no evidence of Tapirus from Pasalar ( contra Becker-Platen et al. [1975], Nagatoshi [1987]). Chalicotherium grande is a Western Eurasian element in the fauna, while the tubulidentate and the hyracoid apparently constitute the oldest records of these African forms outside Afroarabia. The presence of Chalicotherium grande suggest a maximum correlative age of MN5.