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Nairobi, Kenya

Tryon C.A.,Harvard University | Crevecoeur I.,University of Bordeaux 1 | Faith J.T.,University of Queensland | Ekshtain R.,Harvard University | And 5 more authors.
Proceedings of the National Academy of Sciences of the United States of America

Kenya National Museums Lukenya Hill Hominid 1 (KNM-LH 1) is a Homo sapiens partial calvaria from site GvJm-22 at Lukenya Hill, Kenya, associated with Later Stone Age (LSA) archaeological deposits. KNM-LH 1 is securely dated to the Late Pleistocene, and samples a time and region important for understanding the origins of modern human diversity. A revised chronology based on 26 accelerator mass spectrometry radiocarbon dates on ostrich eggshells indicates an age range of 23,576-22,887 y B.P. for KNM-LH 1, confirming prior attribution to the Last Glacial Maximum. Additional dates extend the maximum age for archaeological deposits at GvJm-22 to >46,000 y B.P. (>46 kya). These dates are consistent with new analyses identifying both Middle Stone Age and LSA lithic technologies at the site, making GvJm-22 a rare eastern African record of major human behavioral shifts during the Late Pleistocene. Comparative morphometric analyses of the KNM-LH 1 cranium document the temporal and spatial complexity of early modern human morphological variability. Features of cranial shape distinguish KNM-LH 1 and other Middle and Late Pleistocene African fossils from crania of recent Africans and samples from Holocene LSA and European Upper Paleolithic sites. Source

Ward C.V.,University of Missouri | Manthi F.K.,National Museums of Kenya | Plavcan J.M.,University of Arkansas
Journal of Human Evolution

Renewed fieldwork from 2003 through 2008 at the Australopithecus anamensis type-site of Kanapoi, Kenya, yielded nine new fossils attributable to this species. These fossils all date to between 4.195 and 4.108 million years ago. Most were recovered from the lower fluvial sequence at the site, with one from the lacustrine sequence deltaic sands that overlie the lower fluvial deposits but are still below the Kanapoi Tuff. The new specimens include a partial edentulous mandible, partial maxillary dentition, two partial mandibular dentitions, and five isolated teeth. The new Kanapoi hominin fossils increase the sample known from the earliest Australopithecus, and provide new insights into morphology within this taxon. They support the distinctiveness of the early A.anamensis fossils relative to earlier hominins and to the later Australopithecus afarensis. The new fossils do not appreciably extend the range of observed variation in A.anamensis from Kanapoi, with the exception of some slightly larger molars, and a canine tooth root that is the largest in the hominin fossil record. All of the Kanapoi hominins share a distinctive morphology of the canine-premolar complex, typical early hominin low canine crowns but with mesiodistally longer honing teeth than seen in A.afarensis, and large, probably dimorphic, canine tooth roots. The new Kanapoi specimens support the observation that canine crown height, morphology, root size and dimorphism were not altered from a primitive ape-like condition as part of a single event in human evolution, and that there may have been an adaptive difference in canine function between A.anamensis and A.afarensis. © 2013 Elsevier Ltd. Source

Abdillahi H.S.,National Museums of Kenya | Van Staden J.,University of KwaZulu - Natal
Planta Medica

Plants have played significant roles as medicine during pregnancy, birth, and postpartum care in many rural areas of the world. In addition to this, plants have been used for centuries to treat infertility and related reproduction problems. The aim of this paper was to review the current status of plant species used in maternal healthcare, including infertility, in South Africa, in terms of scientific evaluation for efficacy and safety. In addition to this, the role of medicinal plants as a tool in achieving the MDG5 of reducing maternal mortality by 2015 was evaluated. A search was done with the aid of Google Scholar, PubMed, Science Direct, peer-reviewed papers, and books, using keywords such as child birth, labour pain, maternal health, maternal mortality, menstrual pains, and postpartum. The plants listed in the different research articles were classified according to their use and the target effect of a plant extract or compound on reproductive function. Eighty-four plant species were found to be used to treat infertility and related problems. Twenty plant species are used during pregnancy, while 26 plant species are used to ease childbirth. For postpartum healing and any problems after childbirth, nine plant species were recorded. Unhealthy pregnancy and birth complications are among the factors that contribute to the loss of cognitive potential in the developing worlds children, condemning them to impoverished lives. The best way to keep a country poor is to rob its children of their full developmental potential. In this respect, medicinal plants play a significant role in reducing maternal mortality and ensuring the birth of healthy children. © Georg Thieme Verlag KG Stuttgart New York. Source

Cerling T.E.,University of Utah | Chritz K.L.,University of Utah | Jablonski N.G.,Pennsylvania State University | Leakey M.G.,Turkana Basin Institute | And 2 more authors.
Proceedings of the National Academy of Sciences of the United States of America

Theropithecus was a common large-bodied primate that cooccurred with hominins in many Plio-Pleistocene deposits in East and South Africa. Stable isotope analyses of tooth enamel from T. brumpti (4.0-2.5 Ma) and T. oswaldi (2.0-1.0 Ma) in Kenya show that the earliest Theropithecus at 4 Ma had a diet dominated by C4 resources. Progressively, this genus increased the proportion of C4-derived resources in its diet and by 1.0 Ma, had a diet that was nearly 100% C4-derived. It is likely that this diet was comprised of grasses or sedges; stable isotopes cannot, by themselves, give an indication of the relative importance of leaves, seeds, or underground storage organs to the diet of this primate. Theropithecus throughout the 4- to 1-Ma time range has a diet that is more C4-based than contemporaneous hominins of the genera Australopithecus, Kenyanthropus, and Homo; however, Theropithecus and Paranthropus have similar proportions of C4-based resources in their respective diets. Source

Ward C.V.,University of Missouri | Plavcan J.M.,University of Arkansas | Manthi F.K.,National Museums of Kenya | Manthi F.K.,State University of New York at Stony Brook
Philosophical Transactions of the Royal Society B: Biological Sciences

Australopithecus anamensis is the earliest known species of the Australopithecus-human clade and is the likely ancestor of Australopithecus afarensis. Investigating possible selective pressures underlying these changes is key to understanding the patterns of selection shaping the origins and early evolution of the Australopithecus-human clade. During the course of the Au. anamensis-afarensis lineage, significant changes appear to occur particularly in the anterior dentition, but also in jaw structure and molar form, suggesting selection for altered diet and/or food processing. Specifically, canine tooth crown height does not change, but maxillary canines and P3s become shorter mesiodistally, canine tooth crowns become more symmetrical in profile and P3s less unicuspid. Canine roots diminish in size and dimorphism, especially relative to the size of the postcanine teeth. Molar crowns become higher. Tooth rows become more divergent and symphyseal form changes. Dietary change involving anterior dental use is also suggested by less intense anterior tooth wear in Au. afarensis. These dental changes signal selection for altered dietary behaviour and explain some differences in craniofacial form between these taxa. These data identify Au. anamensis not just as a more primitive version of Au. afarensis, but as a dynamic member of an evolving lineage leading to Au. afarensis, and raise intriguing questions about what other evolutionary changes occurred during the early evolution of the Australopithecus-human clade, and what characterized the origins of the group. © 2010 The Royal Society. Source

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