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We describe a partial innominate, YGSP 41216, from a 12.3 Ma locality in the Siwalik Group of the Potwar Plateau in Pakistan, assigned to the Middle Miocene ape species Sivapithecus indicus. We investigate the implications of its morphology for reconstructing positional behavior of this ape. Postcranial anatomy of extant catarrhines falls into two distinct groups, particularly for torso shape. To an extent this reflects different although variable and overlapping positional repertoires: pronograde quadrupedalism for cercopithecoids and orthogrady for hominoids. The YGSP innominate (hipbone) is from a primate with a narrow torso, resembling most extant monkeys and differing from the broader torsos of extant apes. Other postcranial material of S. indicus and its younger and similar congener Sivapithecus sivalensis also supports reconstruction of a hominoid with a positional repertoire more similar to the pronograde quadrupedal patterns of most monkeys than to the orthograde patterns of apes. However, Sivapithecus postcranial morphology differs in many details from any extant species. We reconstruct a slow-moving, deliberate, arboreal animal, primarily traveling above supports but also frequently engaging in antipronograde behaviors. There are no obvious synapomorphic postcranial features shared exclusively with any extant crown hominid, including Pongo. [ABSTRACT FROM AUTHOR]

Here, we report on a new collection of mostly isolated molars of a colobine monkey from near Hasnot on the Potwar Plateau of Pakistan. The specimens are from three late Miocene localities, with ages constrained to between 7.9 and 7.1 Ma. Morphological and metrical comparisons of the new Hasnot molars with those of previously recognized Mesopithecus species and living Asian colobines lead to the conclusion that the Hasnot colobine is most probably Mesopithecus , but not Mesopithecus pentelicus. The most morphologically distinctive aspect of the Hasnot specimens is the lower third molars, which exhibit large and bulbous protoconids set off by deeply incised mesial buccal and median buccal clefts and large, broad distobuccally placed hypoconulids. Colobine specimens previously recovered from the Potwar Plateau have been assigned to Mesopithecus sivalensis , but because these specimens have not yet been fully described, a detailed comparison with the new Hasnot specimens is not yet possible. For these reasons, we assign the new Hasnot colobine fossils to cf. Mesopithecus sp. Mesopithecus was one of the most widespread and successful of late Miocene primates. As a colobine equipped with features of the molar teeth, limbs, and, presumably, gut enabling it to succeed in more highly seasonal woodland environments, Mesopithecus was able to rapidly disperse into and adapt to the conditions in South Asia brought about by profound climatic and concomitant environmental change during the latest Miocene. [ABSTRACT FROM AUTHOR]

Several new postcranial elements of Sivapithecus from the Siwaliks of Pakistan are described. These include a distal femur from the U-level of the Dhok Pathan Formation, a navicular from the Chinji Formation, and seven manual and pedal phalanges from the Nagri Formation. The functional morphology of these elements adds new detail to the reconstruction ofSivapithecus positional behavior. Femoral cross-sectional geometry indicates that the shaft was adapted to support mediolaterally directed loading. Femoral condylar asymmetry and a broad but shallow trochlea are distinctly ape-like, revealing capabilities for both rotation and withstanding eccentric loading in the knee. The navicular is characterized by features relating to a broad mid-tarsus and broad distal articulations for the cuneiforms. It also lacks a navicular tubercle as in Pongo. These features suggest that the foot was capable of a powerful grip on large supports, with an inversion/supination capability that would permit foot placement in a variety of positions. The morphology of the new phalanges, including evidence for a relatively large pollex, similarly suggests powerful grasping, consistent with prior evidence from the hallux and tarsus. The functional features of the new specimens permit refinement of previous interpretations of Sivapithecus positional capabilities. They suggest a locomotor repertoire dominated by pronograde activities and also such antipronograde activities as vertical climbing and clambering, but not by antipronograde suspensory activities as practiced by extant apes. [Copyright &y& Elsevier]

Abstract: During the past decade, studies of enamel development have provided a broad temporal and geographic perspective on evolutionary developmental biology in Miocene hominoids. Here we report some of the first data for molar crown development in one hominoid genus, Sivapithecus. The data are compared to a range of extant and extinct hominoids. Crown formation times (CFTs), daily rates of enamel secretion (DSR), Retzius line number and periodicity, and relative enamel thickness (RET) were calculated in a mandibular first molar of Sivapithecus parvada and a maxillary first molar of Sivapithecus indicus from the Siwalik sequence of Pakistan. A CFT of 2.40 years for the protoconid of S. parvada and 2.25 years for the protocone of S. indicus lie within the range of first molar (M1) formation times for the majority of Miocene hominoids (1.96–2.40 years, excluding Proconsul heseloni), and are similar to an M1 from Gorilla (2.31 years) and M1s from Pan (2.22–2.39 years). This is unlike the longer CFTs in modern humans, which appear to be linked with their extended growth period. In contrast to extant great apes and humans, daily rates of enamel secretion are rapid in the Sivapithecus M1s during the early stages of growth, which seems to be a common pattern for most Miocene apes. The rapid accumulation of cuspal enamel in the Sivapithecus molars produced thicker enamel than either Pan or Gorilla in a comparable period of time. Future studies on larger samples of living and fossil hominoids are needed to clarify trends in crown development, which may be better understood in the context of life history strategies coupled with good data on body mass and brain size. [Copyright &y& Elsevier]

Several new postcranial elements of Sivapithecus from the Siwaliks of Pakistan are described. These include a distal femur from the U-level of the Dhok Pathan Formation, a navicular from the Chinji Formation, and seven manual and pedal phalanges from the Nagri Formation. The functional morphology of these elements adds new detail to the reconstruction of Sivapithecus positional behavior. Femoral cross-sectional geometry indicates that the shaft was adapted to support mediolaterally directed loading. Femoral condylar asymmetry and a broad but shallow trochlea are distinctly ape-like, revealing capabilities for both rotation and withstanding eccentric loading in the knee. The navicular is characterized by features relating to a broad mid-tarsus and broad distal articulations for the cuneiforms. It also lacks a navicular tubercle as in Pongo. These features suggest that the foot was capable of a powerful grip on large supports, with an inversion/supination capability that would permit foot placement in a variety of positions. The morphology of the new phalanges, including evidence for a relatively large pollex, similarly suggests powerful grasping, consistent with prior evidence from the hallux and tarsus. The functional features of the new specimens permit refinement of previous interpretations of Sivapithecus positional capabilities. They suggest a locomotor repertoire dominated by pronograde activities and also such antipronograde activities as vertical climbing and clambering, but not by antipronograde suspensory activities as practiced by extant apes., (Copyright 2002 Elsevier Science Ltd. All rights reserved.)