The cranium of Parapithecus grangeri, an Egyptian Oligocene anthropoidean primate.
نویسنده
چکیده
A nearly complete skull of Parapithecus grangeri from the early Oligocene of Egypt is described. The specimen is relatively undistorted and is undoubtedly the most complete higher primate skull yet found in the African Oligocene, which also makes it the most complete Oligocene primate cranium worldwide. Belonging in superfamily Parapithecoidea, a group regarded by some as the sister group to all other Anthropoidea, this skull reveals important information about the radiation of stem anthropoideans. This cranium is about 15% larger than size estimates based on a fragmentary cranium of its contemporary and close relative Apidium phiomense. It is about the same size as that of the gray gentle lemur, Hapalemur griseus, or of platyrrhines such as the owl monkey, Aotus trivirgatus, or the titi monkey, Callicebus torquatus. Comparatively small orbits and size differences in jaws and teeth show it was both diurnal and dimorphic. This is the only specimen of the species that shows (from sockets) that there were four small upper incisors. Several mandibular specimens of the species establish that there were no permanent lower incisors and that the symphysis was fused. Like other early anthropoideans this species possessed a lower encephalization quotient and less-developed orbital frontality than later anthropoideans. There is full postorbital closure and fusion of the metopic suture, and the ectotympanic forms a rim to the auditory aperture. A probable frontal/alisphenoid contact is a potentially derived resemblance to Catarrhini. A proposed separate genus for the species P. grangeri is not sustained.
منابع مشابه
Parapithecus Grangeri (parapithecidae, Old World Higher Primates) New Species from the Oligocene of Egypt and the Initial Differentiation of Cercopithecoidea
Among many primate fossils from the badlands of Oligocene age in the Fayum Province, Egypt, are specimens of a new species of the genus Parapithecus. The new materials for the first time provide evidence of the upper dentition and mandibular materials show that all the early determinations as to the dental formula of the type species of Parapithecus, P. fraasi, were incorrect. The new species, ...
متن کاملHigh-resolution computed tomography study of the cranium of a fossil anthropoid primate, Parapithecus grangeri: new insights into the evolutionary history of primate sensory systems.
Extant anthropoids have large brains, small olfactory bulbs, and high-acuity vision compared with other primates. The relative timing of the evolution of these characteristics may have important implications for brain evolution. Here computed tomography is used to examine the cranium of a fossil anthropoid, Parapithecus grangeri. It is found that P. grangeri had a relatively small brain compare...
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 98 14 شماره
صفحات -
تاریخ انتشار 2001