The taphonomy of a micromammalian faunal assemblage from the Saldanha Bay Yacht Club : a contribution to the study of the South African west coast palaeoenvironments

Bibliography: leaves 129-146.This thesis provides a broad outline of the effect of taphonomic and ecological processes on the accumulation and transformation of micromammalian faunal assemblages, and the importance of the signatures left behind by these processes in the reconstruction of ancient ecosystems. Micromammalian remains recovered from a rich Terminal Pleistocene site near the Saldanha Bay Yacht Club (SBYC) along the South African west coast have been examined following Andrews' (1990a) procedures. In the investigation of the effect of taphonomy on the SBYC faunal remains, murids (rodents) and soricids (shrews) have been examined separately and in as much detail as possible. The analyses have shown that the long bones of the soricids exhibit a relatively higher degree of completeness than those of the murids, suggesting preferential preservation of the former. Additionally, soricid jaws have yielded higher minimum number of individuals (MNIs) than long bone counts whereas for murids the opposite is the case. These observations have indicated the need for more taxonomically resolved analyses on the effect of taphonomic processes on micromammalian remains. Three micromammalian species represented in the SBYC faunal samples (Tatera afra, Myosorex varius and Suncus varilla) yielded much higher MNI counts than did other species. This reflects the intermediate selective behaviour of the inferred accumulator of the fauna, the barn owl, although the spotted eagle owl has not been completely ruled out. The study of the SBYC micromammalian fauna has underscored the need to integrate both taphonomic and ecological factors in the attempts to infer potential predators that might have been responsible for the accumulation of microanalytic occurrences. This is also necessary for understanding the environmental contexts in which the fauna was accumulated and/or derived. The micromammalian species represented at SBYC have suggested that in the SBYC area some 15,000 years ago, there was a mosaic of microhabitats including well-vegetated and moist microhabitats, and an admixture of bush and sandveld. Overall, climatic conditions in the SBYC area when the microfauna accumulated were moderate, and generally not different from the conditions prevailing today

The ecology of Australopithecus anamensis in the early Pliocene of Kanapoi, Kenya

Australopithecus anamensis is a pivotal species in human evolution. It is likely to be the direct ancestor of Australopithecus afarensis and the species that may have given rise to the Homo and Paranthropus lineages. It had a suite of adaptations for habitual bipedalism and a diet that differed from that of earlier hominin species. Under what environmental and ecological conditions did this suite of adaptations arise? The early Pliocene site of Kanapoi in the Lake Turkana Basin of Kenya has the largest sample of A. anamensis in eastern Africa and a rich record of fossil vertebrates. Most Kanapoi fossils are chronologically well constrained by radiometrically dated tephras between the ages of 4.2 and 4.1 million years ago. Sedimentological, isotopic, and faunal data indicate that the environments of Kanapoi during the early Pliocene had a complex range of vegetation types that included closed woodlands, shrubs, and grasslands near a river (for most of the sequence) or lake. These were dynamic landscapes that could shift rapidly from fluvial to lacustrine conditions, and then back. Australopithecus anamensis shared its environments with at least 10 species of very large herbivores, which undoubtedly played a major role in modifying the landscape by opening wooded areas and providing pathways for bipedal hominins. Hominins may have competed for terrestrial resources with abundant suids (Nyanzachoerus and Notochoerus) and for arboreal resources with monkeys (Parapapio being the most common cercopithecid). Kanapoi had a formidable group of predators that included a very abundant species of hyena (Parahyaena howelli), two sabre-tooth felids (Dinofelis and Homotherium), a giant otter (Enhydriodon cf. dikikae), and three species of crocodiles. Various measures of abundance indicate that A. anamensis was an important component of the Kanapoi early Pliocene ecosystems, and that its key adaptations allowed this species to thrive in complex and dynamic landscapes. (C) 2019 Elsevier Ltd. All rights reserved.Leakey FoundationPaleontological Scientific Trust (PAST) of South AfricaNational Science FoundationNational Science Foundation (NSF)University of Missouri Research Boardinfo:eu-repo/semantics/publishedVersio

Ancient DNA and deep population structure in sub-Saharan African foragers

Multiple lines of genetic and archaeological evidence suggest that there were major demographic changes in the terminal Late Pleistocene epoch and early Holocene epoch of sub-Saharan Africa(1-4). Inferences about this period are challenging to make because demographic shifts in the past 5,000 years have obscured the structures of more ancient populations(3,5). Here we present genome-wide ancient DNA data for six individuals from eastern and south-central Africa spanning the past approximately 18,000 years (doubling the time depth of sub-Saharan African ancient DNA), increase the data quality for 15 previously published ancient individuals and analyse these alongside data from 13 other published ancient individuals. The ancestry of the individuals in our study area can be modelled as a geographically structured mixture of three highly divergent source populations, probably reflecting Pleistocene interactions around 80-20 thousand years ago, including deeply diverged eastern and southern African lineages, plus a previously unappreciated ubiquitous distribution of ancestry that occurs in highest proportion today in central African rainforest hunter-gatherers. Once established, this structure remained highly stable, with limited long-range gene flow. These results provide a new line of genetic evidence in support of hypotheses that have emerged from archaeological analyses but remain contested, suggesting increasing regionalization at the end of the Pleistocene epoch. DNA analysis of 6 individuals from eastern and south-central Africa spanning the past approximately 18,000 years, and of 28 previously published ancient individuals, provides genetic evidence supporting hypotheses of increasing regionalization at the end of the Pleistocene.info:eu-repo/semantics/publishedVersio

The Pliocene micromammalian fauna from Kanapoi, northwestern Kenya, and its contribution to understanding the environment of Australopithecus anamensis

Includes bibliographical references (leaves 164-202)

Gigantic lion, Panthera leo, from the Pleistocene of Natodomeri, eastern Africa

The partial skull of a lion from Natodomeri, northwest Kenya is described. The Natodomeri sites are correlated with Member I of the Kibish Formation, dated to between 195 ka and ca. 205 ka. The skull is remarkable for its very great size, equivalent to the largest cave lions (Panthera spelaea  [Goldfuss, 1810]) of Pleistocene Eurasia and much larger than any previously known lion from Africa, living or fossil. We hypothesize that this individual represents a previously unknown population or subspecies of lion present in the late Middle and Late Pleistocene of eastern Africa rather than being an indication of climate-driven size increase in lions of that time. This raises questions regarding the extent of our understanding of the pattern and causes of lion evolution in the Late Pleistocene

A glimpse at the ectotherms of the earliest fauna from the East African Rift (Lokone, late Oligocene of Kenya)

International audienc

Fossil lemurs from Egypt and Kenya suggest an African origin for Madagascar’s aye-aye

© 2018, The Author(s). In 1967 G.G. Simpson described three partial mandibles from early Miocene deposits in Kenya that he interpreted as belonging to a new strepsirrhine primate, Propotto. This interpretation was quickly challenged, with the assertion that Propotto was not a primate, but rather a pteropodid fruit bat. The latter interpretation has not been questioned for almost half a century. Here we re-evaluate the affinities of Propotto, drawing upon diverse lines of evidence to establish that this strange mammal is a strepsirrhine primate as originally suggested by Simpson. Moreover, our phylogenetic analyses support the recognition of Propotto, together with late Eocene Plesiopithecus from Egypt, as African stem chiromyiform lemurs that are exclusively related to the extant aye-aye (Daubentonia) from Madagascar. Our results challenge the long-held view that all lemurs are descended from a single ancient colonization of Madagascar, and present an intriguing alternative scenario in which two lemur lineages dispersed from Africa to Madagascar independently, possibly during the later Cenozoic

Fossil lemurs from Egypt and Kenya suggest an African origin for Madagascar’s aye-aye

© 2018, The Author(s). In 1967 G.G. Simpson described three partial mandibles from early Miocene deposits in Kenya that he interpreted as belonging to a new strepsirrhine primate, Propotto. This interpretation was quickly challenged, with the assertion that Propotto was not a primate, but rather a pteropodid fruit bat. The latter interpretation has not been questioned for almost half a century. Here we re-evaluate the affinities of Propotto, drawing upon diverse lines of evidence to establish that this strange mammal is a strepsirrhine primate as originally suggested by Simpson. Moreover, our phylogenetic analyses support the recognition of Propotto, together with late Eocene Plesiopithecus from Egypt, as African stem chiromyiform lemurs that are exclusively related to the extant aye-aye (Daubentonia) from Madagascar. Our results challenge the long-held view that all lemurs are descended from a single ancient colonization of Madagascar, and present an intriguing alternative scenario in which two lemur lineages dispersed from Africa to Madagascar independently, possibly during the later Cenozoic

Kanyimangin: a new 1 million years old sit in West-Turkana, Kenya

The Early to Middle Pleistocene Transition (EMPT 1250-750 ka) is a period characterised by major environmental changes. These changes are reflected in the archaeological and faunal records which are marked by behavioural, cognitive (Acheulean specialisation/expansion) and morphological (encephalisation) innovations within the genus Homo. Unfortunately, the EMPT African hominin fossil record is scarce and poorly correlated with the archaeological record. Here we present faunal and chronometric data of a newly discovered EMPT site in West Turkana: Kanyimangin.In August 2017, the Trans-Evol Project started fieldwork in the floodplain of the Kerio River (Turkana Basin, Kenya), identifying a new palaeontological and archaeological locality. Kanyimangin is located within the Kalabata river (a tributary of the Kerio river) circular anomaly, where ca. 15-meter-deep sediments are preserved from erosion by a series of five sandstones. Although there has been almost no focussed local palaeontological and geochronological study, sediments in that area were believed to be older than 3.7 Ma. However, using combined palaeomagnetism and bio-chronological approaches, we obtain an age estimate between 0.90 and 1.19 Ma. Kanyimangin has yielded substantial lithic (n=344) and faunal (n=2155) assemblages originating partly from buried contexts. The latter comprises 212 individual specimens (NISP) distributed across 20 taxa. The faunal spectrum is composed of both aquatic and terrestrial taxa, including: Palaeoloxodon (Elephas) recki cf. recki, Panthera sp., Hyaena hyaena, Equus grevyi, Rhinocerotidae, Kolpochoerus (limnetes) heseloni, Phacocoerus sp., Hippopotamus amphibius, Syncerus caffer, Aepyceros melampus, Alcephalus buselaphus, cf. Nanger granti and a Renducini as well as the narrow-snouted Euthecodon brumpti, a broad-snouted crocodile, turtles/tortoises, snakes, fish and amphibians. Palaeomagnetic results reveal a normal polarity for the archaeology-bearing sandstone and evidence for a subsequent period of reverse polarity. Together with the presence of Palaeoloxodon recki cf. recki recovered from the same sandstone, this suggests a Matuyama age for the site after the Olduvai subchron. To date, most faunal remains were recovered from survey, which limits their biostratigraphic potential; however, the presence of well-fossilised Phacochoerus sp. and Alcephalus buselaphus specimens recovered on the surface of the archaeology-bearing sandstone equally suggests a Jaramillo (1.06–0.90 Ma) or Cobb Mountain (1.19 Ma) age for the site