A new hominid from the Upper Miocene of Chad,Central Africa

The search for the earliest fossil evidence of the human lineage has been concentrated in East Africa. Here we report the discovery of six hominid specimens from Chad, central Africa, 2,500 km from the East African Rift Valley. The fossils include a nearly complete cranium and fragmentary lower jaws. The associated fauna suggest the fossils are between 6 and 7 million years old. The fossils display a unique mosaic of primitive and derived characters, and constitute a new genus and species of hominid. The distance from the Rift Valley, and the great antiquity of the fossils, suggest that the earliest members of the hominid clade were more widely distributed than has been thought, and that the divergence between the human and chimpanzee lineages was earlier than indicated by most molecular studies.     

New material of the earliest hominid from the Upper Miocene of Chad

Discoveries in Chad by the Mission Paleoanthropologique Franco-Tchadienne have substantially changed our understanding of early human evolution in Africa. In particular, the TM 266 locality in the Toros-Menalla fossiliferous area yielded a nearly complete cranium (TM 266-01-60-1), a mandible, and several isolated teeth assigned to Sahelanthropus tchadensis and biochronologically dated to the late Miocene epoch (about 7 million years ago). Despite the relative completeness of the TM 266 cranium, there has been some controversy about its morphology and its status in the hominid clade. Here we describe new dental and mandibular specimens from three Toros-Menalla (Chad) fossiliferous localities (TM 247, TM 266 and TM 292) of the same age. This new material, including a lower canine consistent with a non-honing C/P3 complex, post-canine teeth with primitive root morphology and intermediate radial enamel thickness, is attributed to S. tchadensis. It expands the hypodigm of the species and provides additional anatomical characters that confirm the morphological differences between S. tchadensis and African apes. S. tchadensis presents several key derived features consistent with its position in the hominid clade close to the last common ancestor of chimpanzees and humans.     

Geology and palaeontology of the Late Miocene Middle Awash valley, Afar rift, Ethiopia.

The Middle Awash study area of Ethiopia's Afar rift has yielded abundant vertebrate fossils (approximately 10,000), including several hominid taxa. The study area contains a long sedimentary record spanning Late Miocene (5.3-11.2 Myr ago) to Holocene times. Exposed in a unique tectonic and volcanic transition zone between the main Ethiopian rift (MER) and the Afar rift, sediments along the western Afar rift margin in the Middle Awash provide a unique window on the Late Miocene of Ethiopia. These deposits have now yielded the earliest hominids, described in an accompanying paper and dated here to between 5.54 and 5.77 Myr. These geological and palaeobiological data from the Middle Awash provide fresh perspectives on hominid origins and early evolution. Here we show that these earliest hominids derive from relatively wet and wooded environments that were modulated by tectonic, volcanic, climatic and geomorphic processes. A similar wooded habitat also has been suggested for the 6.0 Myr hominoid fossils recently recovered from Lukeino, Kenya. These findings require fundamental reassessment of models that invoke a significant role for global climatic change and/or savannah habitat in the origin of hominids.     

New hominid skull material from the late Miocene of Macedonia in northern Greece

Miocene hominoid material is very scarce and has previously only been reported as cranial fragments in the Old World. Here we describe a new specimen of Ouranopithecus macedoniensis, which consists of the right part of the face of an adult male with a portion of the frontal bone, a portion of the left part of the face and the maxilla with complete dentition except the right third molar. The characters of this specimen are not congruent with those of Sivapithecus and the pongids, but are more primitive and plesiomorphic for the recent hominid clade (Gorilla, Pan and Homo). The dental characters differ morphologically and metrically from those of the recent great apes and fit better with Australopithecus afarensis. Ouranopithecus now seems the best candidate forerunner of the Plio-pleistocene Homininae (Australopithecus and Homo). This specimen was discovered in September 1989, in the late Miocene deposits of central Macedonia (G.K., L. de B. and G.B.), and prepared by G.K. in Thessaloniki and G. Mouchelin in Poitiers. It comes from the new locality of Xirochori in the red sandstone of the Nea Messimbria formation. The fossil is the property of the University of Thessaloniki, Greece (catalogue number XIR-1).     

Geology and fauna of a new Pliocene locality in north-western Kenya

Lothagam Hill reveals a succession of fossil bearing sediments that extend knowledge of the East African Pliocene back from the base of the Omo succession, to about 5.5 million years.     

New Miocene locality in Turkey with evidence on the origin of Ramapithecus and Sivapithecus.

Collections in early Middle Miocene deposits at Pasalar in Turkey have yielded a very rich fauna. Included in this are two hominoid species referred here to Sivapithecus darwini (Abel) 1902 and Ramapithecus wickeri (Leakey) 1962. These are both more primitive morphologically and earlier in time than other species of these genera, and they provide evdence that Sivapithecus and Ramapithecus are closely related and that their early diversification may have occurred not in Africa but in Eurasia.     

北羌塘盆地北部晚侏罗世索瓦组地层古生物新资料

在北羌塘盆地北部乌兰乌拉湖地区测制了多条晚侏罗世索瓦组剖面,讨论了该区索瓦组的岩性组合特征、沉积环境及空间变化规律.首次系统研究了索瓦组双壳类、层孔虫及珊瑚化石的组合特征及地理分布.建立了一个双壳类生物组合带,一个层孔虫组合和一个珊瑚组合.确定索瓦组的地质时代为晚侏罗世牛津期-基默里奇期.     

西藏双湖托拉木地区侏罗系索瓦组地层古生物

在剖面测制基础上,讨论了北羌塘盆地南部双湖托拉木地区侏罗系索瓦组的岩性组合特征和沉积环境,将索瓦组细分为四个岩性段.根据实测剖面古生物化石的地层分布及组合特征,新建两个生物组合带,即双壳Myopholas multicostata-Protocardia stricklandi-Chlamys (Radulopecten) vagans组合带和珊瑚Stylomilia michelini-Pseudocoenia hexaphyllia 组合带.根据生物组合带的时限及区域地层对比,将索瓦组归于上侏罗统,大致相当于牛津阶-基默里奇阶.     

甘肃临夏盆地中新世地层及哺乳动物化石

甘肃临夏地区中新世哺乳动物化石引起学术界的重视。经过考察、发掘,哪现了大量的化石标本。由于发表的文章多为单篇,较分散,笔者收集整理,对材料进行了研究,认为甘肃临夏地区在近直余年来是全国发现中新世材料最多的地区,且有极高的研究价值,填补了我国中新世哺乳动物化石中的部分空白。     

Late Miocene hominids from the Middle Awash, Ethiopia.

Molecular studies suggest that the lineages leading to humans and chimpanzees diverged approximately 6.5-5.5 million years (Myr) ago, in the Late Miocene. Hominid fossils from this interval, however, are fragmentary and of uncertain phylogenetic status, age, or both. Here I report new hominid specimens from the Middle Awash area of Ethiopia that date to 5.2-5.8 Myr and are associated with a wooded palaeoenvironment. These Late Miocene fossils are assigned to the hominid genus Ardipithecus and represent the earliest definitive evidence of the hominid clade. Derived dental characters are shared exclusively with all younger hominids. This indicates that the fossils probably represent a hominid taxon that postdated the divergence of lineages leading to modern chimpanzees and humans. However, the persistence of primitive dental and postcranial characters in these new fossils indicates that Ardipithecus was phylogenetically close to the common ancestor of chimpanzees and humans. These new findings raise additional questions about the claimed hominid status of Orrorin tugenensis, recently described from Kenya and dated to approximately 6 Myr.     

乍得Bongor盆地潜山岩性识别及储层测井综合评价

潜山油藏作为非常规油藏之一,近年来随着研究的深入,陆续实现突破。Bongor盆地2013年首次发现潜山油藏,针对该盆地潜山岩性复杂,储集空间多样,储层识别和评价难度较大的问题,通过对大量的岩心数据进行分析,基本厘清了Bongor盆地潜山岩性,通过分析不同岩性的测井响应特征,确定了岩性识别定量标准。在此基础上通过岩石力学实验分析其力学性质,优选出了优势岩性,并利用常规测井曲线,结合全烃值和峰基比的方法,首次建立了该盆地潜山油藏储层和油层定性定量识别标准,取得了较好的应用效果。     

Juvenile hominoid cranium from the terminal Miocene of Yunnan, China

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.     

Palaeo-altimetry of the late Eocene to Miocene Lunpola basin, central Tibet

The elevation history of the Tibetan plateau provides direct insight into the tectonic processes associated with continent-continent collisions. Here we present oxygen-isotope-based estimates of the palaeo-altimetry of late Eocene and younger deposits of the Lunpola basin in the centre of the plateau, which indicate that the surface of Tibet has been at an elevation of more than 4 kilometres for at least the past 35 million years. We conclude that crustal, but not mantle, thickening models, combined with plate-kinematic solutions of India-Asia convergence, are compatible with palaeo-elevation estimates across the Tibetan plateau.