Turkana Basin Institute

Nairobi, Kenya

Turkana Basin Institute

Nairobi, Kenya
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Analysis of Egyptian fossils has identified a new species of extinct carnivorous mammals called hyaenodonts, according to a study published April 19, 2017 in the open-access journal PLOS ONE by Matthew Borths from Ohio University, United States of America, and Erik Seiffert from University of Southern California, United States of America. Hyaenodonts preceded modern terrestrial carnivores in Africa and also lived in Europe, Asia, and North America. Some were tree-dwelling; others were terrestrial. The Afro-Arabian hyaenodont records are the oldest, making them key to understanding the evolution of these extinct meat-eaters. The authors of the present study characterized 34 million-year-old Egyptian fossils of a new skunk-sized species of hyaenodont. They named it Masrasector nananubis, the species name referring to Anubis, the canine-headed Egyptian god associated with the afterlife. This hyaenodont was a teratodontine, a carnivorous clade that has been difficult to align with other lineages due to poorly known cranial anatomy. The fossils of the new hyaenodont are the most complete known remains of a teratodontine from the Paleogene Period, and include largely complete skulls, jaws and limb bones. Based on the morphology of the new hyaenodont's bones, the researchers concluded that teratodontines are a close sister group of Hyainailourinae, one of two major hyaenodont clades that were hypercarnivorous, eating mostly meat. Comparison of the limb bones with those of other meat-eating mammals suggests that the new species was terrestrial and moved fast. The researchers state that the fossils of this new species will inform all future explorations of hyaenodont evolution and ecological diversity. "Hyaenodonts were the the top predators in Africa after the extinction of the dinosaurs," says Borths. "This new species is associated with a dozen specimens, including skulls and arm bones, which means we can explore what it ate, how it moved, and consider why these carnivorous mammals died off as the relatives of dogs, cats, and hyenas moved into Africa." In your coverage please use this URL to provide access to the freely available article in PLOS ONE: http://journals. Citation: Borths MR, Seiffert ER (2017) Craniodental and humeral morphology of a new species of Masrasector (Teratodontinae, Hyaenodonta, Placentalia) from the late Eocene of Egypt and locomotor diversity in hyaenodonts. PLoS ONE 12(4): e0173527. doi:10.1371/journal.pone.0173527 Funding: Field work in the Fayum Depression, Egypt, and digital curation of Fayum fossils is supported by the U.S. National Science Foundation through grants BCS-0416164, BCS-0819186, and BCS-1231288, Gordon and Ann Getty, and The Leakey Foundation. MRB was supported by a U.S. National Science Foundation Doctoral Dissertation Improvement Grant (DEB-1311354, a National Science Foundation Graduate Research Fellowship, a Turkana Basin Institute Graduate Fellowship, and a Stony Brook University Graduate Council Fellowship, and is currently supported by a U.S. National Science Foundation Postdoctoral Fellowship in Biology (DBI-1612062. Portions of the data acquisition for this study were also supported by grants from The Explorers Club and the Society for Integrative and Comparative Biology. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist.

Spoor F.,University College London | Spoor F.,Max Planck Institute for Evolutionary Anthropology | Leakey M.G.,Turkana Basin Institute | Leakey M.G.,State University of New York at Stony Brook | O'Higgins P.,University of York
Philosophical Transactions of the Royal Society B: Biological Sciences | Year: 2016

Geometric morphometric shape analyses are used to compare the maxillae of the Kenyanthropus platyops holotype KNM-WT 40000, the Australopithecus deyiremeda holotype BRT-VP-3/1 and other australopiths. The main aim is to explore the relationship between these two specimens and contemporary Australopithecus afarensis. Five landmarks placed on lateral views of the maxillae quantify key aspects of the morphology. Generalized Procrustes analyses and principal component analyses of the resulting shape coordinates were performed. The magnitudes of differences in shape and their significances were assessed using Procrustes and Mahalanobis’ distances, respectively. Both KNM-WT 40000 and BRT-VP-3/1 show statistically significant differences in maxillary shape from A. afarensis, but do so in dissimilar ways. Moreover, the former differs more from A. afarensis than the latter. KNM-WT 40000 has a more anteriorly positioned zygomatic process with a transversely flat, and more orthognathic subnasal clivus. BRT-VP-3/1 has a more inferiorly positioned zygomatic process, a slightly retracted dental arcade, but without shortening of the anterior maxilla. These findings are consistent with previous conclusions that the two fossils should be attributed to separate species, rather than to A. afarensis, and with the presence of three contemporary hominin species in the Middle Pliocene of eastern Africa. © 2016 The Author(s) Published by the Royal Society. All rights reserved.

Lahr M.M.,University of Cambridge | Lahr M.M.,Turkana Basin Institute | Rivera F.,University of Cambridge | Power R.K.,University of Cambridge | And 21 more authors.
Nature | Year: 2016

The nature of inter-group relations among prehistoric hunter-gatherers remains disputed, with arguments in favour and against the existence of warfare before the development of sedentary societies. Here we report on a case of inter-group violence towards a group of hunter-gatherers from Nataruk, west of Lake Turkana, which during the late Pleistocene/early Holocene period extended about 30 km beyond its present-day shore. Ten of the twelve articulated skeletons found at Nataruk show evidence of having died violently at the edge of a lagoon, into which some of the bodies fell. The remains from Nataruk are unique, preserved by the particular conditions of the lagoon with no evidence of deliberate burial. They offer a rare glimpse into the life and death of past foraging people, and evidence that warfare was part of the repertoire of inter-group relations among prehistoric hunter-gatherers. © 2016 Macmillan Publishers Limited. All rights reserved.

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 | Year: 2013

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.

Mounier A.,University of Cambridge | Mounier A.,Aix - Marseille University | Mirazon Lahr M.,University of Cambridge | Mirazon Lahr M.,Turkana Basin Institute
Journal of Human Evolution | Year: 2016

The timing and geographic origin of the common ancestor of modern humans and Neandertals remain controversial. A poor Pleistocene hominin fossil record and the evolutionary complexities introduced by dispersals and regionalisation of lineages have fuelled taxonomic uncertainty, while new ancient genomic data have raised completely new questions. Here, we use maximum likelihood and 3D geometric morphometric methods to predict possible morphologies of the last common ancestor of modern humans and Neandertals from a simplified, fully resolved phylogeny. We describe the fully rendered 3D shapes of the predicted ancestors of humans and Neandertals, and assess their similarity to individual fossils or populations of fossils of Pleistocene age. Our results support models of an Afro-European ancestral population in the Middle Pleistocene (Homo heidelbergensis sensu lato) and further predict an African origin for this ancestral population. © 2015 Elsevier Ltd.

Cerling T.E.,University of Utah | Mbua E.,National Museums of Kenya | Kirera F.M.,National Museums of Kenya | Manthi F.K.,National Museums of Kenya | And 6 more authors.
Proceedings of the National Academy of Sciences of the United States of America | Year: 2011

The East African hominin Paranthropus boisei was characterized by a suite of craniodental features that have been widely interpreted as adaptations to a diet that consisted of hard objects that required powerful peak masticatory loads. These morphological adaptations represent the culmination of an evolutionary trend that began in earlier taxa such as Australopithecus afarensis, and presumably facilitated utilization of open habitats in the Plio-Pleistocene. Here, we use stable isotopes to show that P. boisei had a diet that was dominated by C4 biomass such as grasses or sedges. Its diet included more C4 biomass than any other hominin studied to date, including its congener Paranthropus robustus from South Africa. These results, coupled with recent evidence from dental microwear, may indicate that the remarkable craniodental morphology of this taxon represents an adaptation for processing large quantities of low-quality vegetation rather than hard objects.

Sponheimer M.,University of Colorado at Boulder | Alemseged Z.,California Academy of Sciences | Cerling T.E.,University of Utah | Grine F.E.,State University of New York at Stony Brook | And 8 more authors.
Proceedings of the National Academy of Sciences of the United States of America | Year: 2013

Carbon isotope studies of early hominins from southern Africa showed that their diets differed markedly from the diets of extant apes. Only recently, however, has a major influx of isotopic data from eastern Africa allowed for broad taxonomic, temporal, and regional comparisons among hominins. Before 4 Ma, hominins had diets that were dominated by C3 resources and were, in that sense, similar to extant chimpanzees. By about 3.5 Ma, multiple hominin taxa began incorporating 13C-enriched [C4 or crassulacean acid metabolism (CAM)] foods in their diets and had highly variable carbon isotope compositions which are atypical for African mammals. By about 2.5 Ma, Paranthropus in eastern Africa diverged toward C4/CAM specialization and occupied an isotopic niche unknown in catarrhine primates, except in the fossil relations of grass-eating geladas (Theropithecus gelada). At the same time, other taxa (e.g., Australopithecus africanus) continued to have highly mixed and varied C3/C4 diets. Overall, there is a trend toward greater consumption of 13C-enriched foods in early hominins over time, although this trend varies by region. Hominin carbon isotope ratios also increase with postcanine tooth area and mandibular cross-sectional area, which could indicate that these foods played a role in the evolution of australopith masticatory robusticity. The 13C-enriched resources that hominins ate remain unknown and must await additional integration of existing paleodietary proxy data and new research on the distribution, abundance, nutrition, and mechanical properties of C4 (and CAM) plants.

Martins D.J.,Harvard University | Martins D.J.,Turkana Basin Institute | Collins S.C.,African Butterfly Research Institute | Congdon C.,African Butterfly Research Institute | Pierce N.E.,Harvard University
Biological Journal of the Linnean Society | Year: 2013

The African lycaenid butterfly, Anthene usamba, is an obligate myrmecophile of the acacia ant, Crematogaster mimosae. Female butterflies use the presence of C. mimosae as an oviposition cue. The eggs are laid on the foliage and young branches of the host plant, Acacia drepanolobium. Larvae shelter in the swollen thorns (domatia) of the host tree, where they live in close association with the acacia ants, and each larva occupies a domatium singly. Anthene usamba are tended by ants that feed from the dorsal nectary organ at regular intervals. Larvae also possess tentacle organs flanking the dorsal nectary organ and appear to signal to ants by everting these structures. Larvae were observed to spend most of their time within the domatia. Stable isotope analysis of matched host plant-ant-butterfly samples revealed that Anthene usamba are δ15N enriched relative to the ants with which they associate. These data, based on the increase in δ15N through trophic levels, indicate that the caterpillars of these butterflies are aphytophagous and either exploit the ant brood of C. mimosae within the domatia, or are fed mouth to mouth by adult workers via trophallaxis. This is the first documented case of aphytophagy in African Anthene. Pupation occurs inside the domatium and the imago emerges and departs via the hole chewed by the larva. The adult females remain closely associated with their natal patch of trees, whereas males disperse more widely across the acacia savannah. Females prefer to oviposit on trees with the specific host ant, C. mimosae, an aggressive obligate mutualist, and avoid neighbouring trees with other ant species. Adult butterflies are active during most months of the year, and there are at least two to three generations each year. Observations made over a 5-year period indicate that a number of different lycaenid species utilize ant-acacias in East Africa, and these observations are summarized, together with comparisons from the literature. © 2013 The Linnean Society of London.

Martins D.J.,University of KwaZulu - Natal | Martins D.J.,Turkana Basin Institute | Johnson S.D.,University of KwaZulu - Natal
Biological Journal of the Linnean Society | Year: 2013

Hawkmoths (Lepidoptera, Sphingidae) are considered important pollinators in tropical regions, but the frequency and degree of reciprocal specialization of interactions between hawkmoths and flowers remain poorly understood. Detailed observations at two sites in Kenya over a two-year period indicate that adult hawkmoths are routinely polyphagous and opportunistic, regardless of their proboscis length. About 700 individuals of 13 hawkmoth species were observed visiting a wide range of plant species at the study sites, including 25 taxa that appear to be specifically adapted for pollination by hawkmoths. We estimate that 277 plant species in Kenya (c. 4.61% of the total angiosperm flora) are adapted for pollination by hawkmoths. Floral tube lengths of these plants have a bimodal distribution, reflecting the existence of two hawkmoth guilds differing in tongue length. Hawkmoths exhibited strongly crepuscular foraging patterns with activity confined to a 20-min period at dusk and, in some cases, a similar period just before dawn. Corolla tube length appears to act as a mechanical filter as the longest-tubed plants were visited by the fewest hawkmoth species and these were exclusively from the long-tongued guild. Tube length showed a strong positive relationship with nectar volume, even after phylogenetic correction, which implies that plants with long corolla tubes are under selection to offer relatively large amounts of nectar to entice visits by polyphagous long-tongued hawkmoths. Our study shows that diffusely co-evolved pollination systems involving long-tongued hawkmoths are clearly asymmetrical, with plants exhibiting a high degree of floral specialization, while hawkmoths exhibit polyphagous behaviour. © 2013 The Linnean Society of London.

News Article | November 29, 2015
Site: www.sciencenews.org

“Armchair anthropologist” takes on new meaning at FossilFinder.org. The citizen science website is seeking volunteers to look for fossils and stone tools and to classify rocks captured in aerial photos of Kenya’s Lake Turkana Basin. The basin has been home to important discoveries in human evolution, including many hominid fossils and the earliest known stone tools (SN: 6/13/15, p. 6). Researchers at the University of Bradford in England and the Turkana Basin Institute teamed up to create Fossil Finder. Using radio-controlled helicopters, as well as cameras hung from kites and photographic poles, the team has collected more than 900,000 images from a roughly 4-hectare swath of land. About 46,000 of these photos are online and more are being added regularly, says project coinvestigator Adrian Evans of Bradford. “The aim is to surpass what could be ordinarily achieved with a more traditional boots-on-the-ground model of exploration,” Evans says. With more eyes carefully surveying the area, the team hopes to get a better look at Lake Turkana’s past environment. Using Fossil Finder doesn’t require special skill, but it does take some practice. The website lacks a tutorial, but helpful pop-up windows explain what to look for and how to classify various types of rocks, fossils and other objects. The quality of the photos vary: Some have a resolution as high as 0.3 millimeters while others are too blurry to classify. Users have already analyzed over 32,000 images, and have uncovered some neat finds, including an extinct crocodile specimen, hippopotamus teeth and stone tools. In February, Evans says, the team intends to visit Lake Turkana to investigate these and other promising discoveries.

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