Abstract
Although East Asia (including South Asia) is among three main habitats (Africa, South to East Asia, Central and South America) of extant primates, the evolutionary history of the Tertiary East Asian primates is still obscure. In this paper the Tertiary primate fossils of this area are reviewed. The fossil records suggest that the only extant primate lineage which is supposed to have originated in East Asia is tarsiers and that all other Asian primates have invaded from some other continent, such as Africa, Europe, and North America. However, the evolutionary process of the invasions of primates looks very complicated.
Pseudoprimates (=plesiadapiformes) and strepsirrhines (adapoids and omomyoids) discovered from the late Paleocene/Eocene of East Asia are likely to have invaded from North America and/or Europe. Although the discoveries of the middle/late Eocene “possible anthropoids”, such as eosimids and amphipithecids, suggest the Asian Origin hypothesis for anthropoids, no descendants of these “possible anthropoids” have been discovered from the Oligocene sediments in East Asia. Therefore, the “direct” ancestral stock for the extant anthropoid primates are likely to be derived from the late Eocene/early Oligocene primitive anthropoids from Africa, such as the Fayum anthropoids.
During the Miocene age, at least four different primate lineages have invaded into East Asia: (1) early catarrhines (pliopithecids), (2) hominoids (sivapithecids, dryopithecids), (3) lorrisids, (4) Old World monkeys (colobines, cercopithecids). These primates can be classified into three types according to their invasion route: (1) pliopithecids, an early catarrhine widely distributed in East Asia, (2) “southern route” group, including pliopithecids, sivapithecids, lorisids, most colobines, and cercopithecids, and (3) “northern route” group, including driopithecids and one of the colobines (Dolichopithecus). The “southern route” groups have invaded into Asia directly from Africa, while the “northern route” groups seem to have invaded from Europe, suggesting that they were adapted to the “European-type” flora.
