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The relationship between long‐sequence climate change and Miocene hominoid evolution in the Yunnan region of southwestern China has recently received some attention, partly because this region has been regarded as a "refugium" for hominoids at the end of the Miocene. Here, we carry out a high‐resolution reconstruction of climate evolution in the Zhaotong Basin of Yunnan through the late Miocene to Pliocene using chemical weathering indices and other proxies. The results reveal gradual cooling within generally warm and humid conditions from 8.8–6.2 Ma; three more marked cooling episodes from 6.2–5.0 Ma; cool and humid conditions from 5.0–2.8 Ma; finally, cold and humid conditions from 2.8–2.62 Ma. The evidence is compatible with a scenario in which terminal Miocene cooling episodes within a prevailing warm and humid climate, and associated changes in vegetation, may have been critical factors in the disappearance of hominoids from this region. Plain Language Summary: Orangutans are the only Asian great apes living today, the sole remnants of a far more important radiation that occurred during the Miocene, when several species of apes are recorded from Asia, from Turkey into Pakistan, and India, and China. The Yunnan region of southwestern China has long been regarded as a "refugium" for late Miocene hominoids, as most species became extinct in Africa, Europe, and South Asia. But what caused Miocene hominoids to disappear in the Yunnan region at the southeastern margin of the Tibetan Plateau? We reconstructed a high‐resolution climate records from sediment chemical weathering, and our results suggest that warm and humid climate conditions prevailed during the known period of hominoid occupation in the region, but episodes of climate cooling at 6.2 Ma may have disrupted "refugium" and resulted in the disappearance of hominoids from the region. Key Points: Generally warm and humid climate conditions during the late Miocene in southwest China provide a "refugium" for hominoids in this regionThere were four stages of climate change during the late Miocene through Pliocene in the region, including four episodes of cooler climateThe terminal Miocene cooling episodes may have been factors in the disappearance of hominoids from this region [ABSTRACT FROM AUTHOR]

Fossil suid specimens recovered from the latest Miocene site of Shuitangba, Zhaotong Basin, Yunnan Province, provide new information on the classification and relationship of Chinese Miocene Suinae. Most of the recovered specimens are referred to a relatively advanced and large species of Suinae, Propotamochoerus hyotherioides, based on dental dimensions and morphology. Detailed morphological comparisons were made between the Shuitangba Pr. hyotherioides and other Asian Miocene suines. From these comparisons, we suggest that Pr. hyotherioides from Shuitangba and northern China may be relatively derived compared to the specimens from Lufeng and Yuanmou, southern China and that Pr. hyotherioides and Pr. wui represent separate branches of the genus in China. Furthermore, Microstonyx differs from Pr. hyotherioides in p4/P4 and m3/M3 characters. Molarochoerus is suggested to represent a relatively derived taxon due to the uniquely molarized upper and lower fourth premolars. Miochoerus youngi is suggested to have a closer relationship to Sus and Microstonyx than to Propotamochoerus due to its small size and p4 morphology. Hippopotamodon ultimus, Potamochoerus chinhsienense, Dicoryphochoerus medius, and D. binxianensis exhibit complex morphologies that variously resemble Propotamochoerus, Microstonyx, and Sus and are suggested to be possible transitional forms between Propotamochoerus, Microstonyx, and Sus. However, the resolution of their classification requires further analysis when more material is recovered. [ABSTRACT FROM AUTHOR]

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]

The article reports that Middle Siwalik sediments exposed at Haritalyangar. India are best known for the diversity of fossil primates that no longer inhabit the Sub-Himalaya, including the late surviving large hominoids Sivapithecus and Indopithecus as well as primitive lemuriform primate. The fossils come from the middle level of the Haritalyangar stratigraphic section, which has a lithostratigraphic profile typical of the Middle Siwaliks of the Potwar Plateau in Pakistan.

Fossil apes are known from several late Miocene localities in Yunnan Province, southwestern China, principally from Shihuiba (Lufeng) and the Yuanmou Basin, and represent three species of Lufengpithecus. They mostly comprise large samples of isolated teeth, but there are also several partial or complete adult crania from Shihuiba and a single juvenile cranium from Yuanmou. Here we describe a new, relatively complete and largely undistorted juvenile cranium from the terminal Miocene locality of Shuitangba, also in Yunnan. It is only the second ape juvenile cranium recovered from the Miocene of Eurasia and it is provisionally assigned to the species present at Shihuiba, Lufengpithecus lufengensis. Lufengpithecus has most often been linked to the extant orangutan, Pongo pygmaeus, but recent studies of the crania from Shihuiba and Yuanmou have demonstrated that this is unlikely. The new cranium reinforces the view that Lufengpithecus represents a distinct, late surviving lineage of large apes in the late Miocene of East Asia that does not appear to be closely affiliated with any extant ape lineage. It substantially increases knowledge of cranial morphology in Lufengpithecus and demonstrates that species of this genus represent a morphologically diverse radiation of apes, which is consistent with the dynamic tectonic and biotic milieu of southwestern China in the late Miocene. [ABSTRACT FROM AUTHOR]

The life histories of early hominins are commonly characterized as being like those of great apes. However, the life histories of the extant great apes differ considerably from one another. Moreover, the extent to which their life histories correlate with the two aspects of morphology used to infer the life histories of fossil species, brain size and dental development, has remained subject to debate. Increased knowledge of great ape life histories and, more recently, dental development -in particular ages at first molar emergence- now make it clearer that the latter is strongly associated with important life-history attributes, whereas brain size, as reflected by cranial capacity, is less informative. Here we estimate ages at M1 emergence in several infant/juvenile individuals of Australopithecus and Paranthropus based on previous estimates of ages at death, determined through dental histology. These are uniformly earlier than would be predicted either by adult cranial capacity or by comparison to ages at M1 emergence in free-living extant great apes. This suggests that either, 1) the life histories of the early hominins were faster than those of all extant great apes; 2) there was selection for rapid initial dental development and presumably early weaning, but that early hominin life histories were otherwise more prolonged and consistent with adult cranial capacities; or 3) the ages at death have been systematically underestimated, resulting in underestimates of the ages at M1 emergence. We investigate the implications of each of these alternatives and, where possible, explore evidence that might support one over the others. [ABSTRACT FROM AUTHOR]

While there is gradually accumulating knowledge about molar crown formation and the timing of molar eruption in extant great apes, very little is known about root formation during the eruption process. We measured mandibular first and second molar root lengths in extant great ape osteological specimens that died while either the first or second molars were in the process of erupting. For most specimens, teeth were removed so that root lengths could be measured directly. When this was not possible, roots were measured radiographically. We were particularly interested in the variation in the lengths of first molar roots near the point of gingival emergence, so specimens were divided into early, middle and late phases of eruption based on the number of cusps that showed protein staining, with one or two cusps stained equated with immediate post-gingival emergence. For first molars at this stage, Gorilla has the longest roots, followed by Pongo and Pan. Variation in first molar mesial root lengths at this stage in Gorilla and Pan, which comprise the largest samples, is relatively low and represents no more than a few months of growth in both taxa. Knowledge of root length at first molar emergence permits an assessment of the contribution of root growth toward differences between great apes and humans in the age at first molar emergence. Root growth makes up a greater percentage of the time between birth and first molar emergence in humans than it does in any of the great apes. [ABSTRACT FROM AUTHOR]

Abstract Kamoyapithecus hamiltoni is a potential early hominoid species described from fragmentary dentognathic specimens from the Oligocene site of Losodok (Turkana Basin, northwestern Kenya). Other catarrhine dental materials have been recovered at Losodok, but were not initially included in the Kamoyapithecus hypodigm. Here we present descriptions of the unpublished canine and incisor specimens from Losodok, and revisit the published specimens in light of recent changes in understanding of hominoid anterior dental evolution. The new fossils include a canine (KNM-LS 18354) that is morphologically compatible with being a female of Kamoyapithecus (KNM-LS 8). Randomization analyses of both Gorilla gorilla and middle Miocene Griphopithecus alpani demonstrate that the size difference between KNM-LS 8 and KNM-LS 18354 is also compatible with their being male and female canines of the same species. Significantly, a canine tip (KNM-LS 18352) attributed to Kamoyapithecus documents the distinctive burin tip morphology now recognized as characterizing Proconsul sensu stricto, which may indicate a close relationship between Kamoyapithecus and Proconsul. We also re-examined the enigmatic KNM-LS 1, a smaller lower canine assumed to derive from Losodok but for which historical provenience data are completely lacking. Elemental data derived from portable X-ray fluorescence spectroscopy show that KNM-LS 1 is almost certainly from Losodok rather than from nearby Miocene sites (i.e., Moruorot, Esha, Kalodirr). KNM-LS 1 displays a nyanzapithecine-like morphology and is shown by randomization analyses to be too small to be associated with the Kamoyapithecus canines. This demonstrates that there is a second hominoid taxon present at Losodok that records one of the earliest occurrences of the Nyanzapithecinae. [ABSTRACT FROM AUTHOR]

Describes a partial hominoid skeleton from a Middle Miocene site located west of Lake Baringo in central Kenya that seems to be an early member of the great ape-human clade. The two species of Kenyapithecus that are currently recognized; Description of this new genus; Etymology.