Science.gov

Sample records for hominins central jawa

  1. Early Pleistocene 40Ar/39Ar ages for Bapang Formation hominins, Central Jawa, Indonesia

    PubMed Central

    Larick, Roy; Ciochon, Russell L.; Zaim, Yahdi; Sudijono; Suminto; Rizal, Yan; Aziz, Fachroel; Reagan, Mark; Heizler, Matthew

    2001-01-01

    The Sangiran dome is the primary stratigraphic window for the Plio-Pleistocene deposits of the Solo basin of Central Jawa. The dome has yielded nearly 80 Homo erectus fossils, around 50 of which have known findspots. With a hornblende 40Ar/39Ar plateau age of 1.66 ± 0.04 mega-annum (Ma) reportedly associated with two fossils [Swisher, C.C., III, Curtis, G. H., Jacob, T., Getty, A. G., Suprijo, A. & Widiasmoro (1994) Science 263, 1118–1121), the dome offers evidence that early Homo dispersed to East Asia during the earliest Pleistocene. Unfortunately, the hornblende pumice was sampled at Jokotingkir Hill, a central locality with complex lithostratigraphic deformation and dubious specimen provenance. To address the antiquity of Sangiran H. erectus more systematically, we investigate the sedimentary framework and hornblende 40Ar/39Ar age for volcanic deposits in the southeast quadrant of the dome. In this sector, Bapang (Kabuh) sediments have their largest exposure, least deformation, and most complete tephrostratigraphy. At five locations, we identify a sequence of sedimentary cycles in which H. erectus fossils are associated with epiclastic pumice. From sampled pumice, eight hornblende separates produced 40Ar/39Ar plateau ages ranging from 1.51 ± 0.08 Ma at the Bapang/Sangiran Formation contact, to 1.02 ± 0.06 Ma, at a point above the hominin-bearing sequence. The chronological sequence of 40Ar/39Ar ages follows stratigraphic order across the southeast quadrant. An intermediate level yielding four nearly complete crania has an age of about 1.25 Ma. PMID:11309488

  2. Ages for hominin occupation in Lushi Basin, middle of South Luo River, central China.

    PubMed

    Lu, Huayu; Sun, Xuefeng; Wang, Shejiang; Cosgrove, Richard; Zhang, Hongyan; Yi, Shuangwen; Ma, Xiaolin; Wei, Ming; Yang, Zhenyu

    2011-05-01

    A newly discovered Paleolithic site in loess deposits in the Lushi Basin, South Luo River, central China, is dated using pedostratigraphic analysis, optically stimulated luminescence (OSL) and magnetostratigraphic analysis. This region is regarded as an important place for hominin occupation and settlement during the early to middle Pleistocene. Results indicate that the archaeological site dates from 600ka to 620ka, reinforcing the view that Homo erectus had occupied a large area of eastern Asia by 620ka. The lithic assemblages of Lushi Basin is a flake and core technology, typical for this time period in north-central China. It may be compared with that at the Zhoukoudian locality 1 in north China and some sites in the Luonan Basin, and provides important data for understanding the behavior and stone tool technology of early Chinese hominins.

  3. First Early Hominin from Central Africa (Ishango, Democratic Republic of Congo)

    PubMed Central

    Crevecoeur, Isabelle; Skinner, Matthew M.; Bailey, Shara E.; Gunz, Philipp; Bortoluzzi, Silvia; Brooks, Alison S.; Burlet, Christian; Cornelissen, Els; De Clerck, Nora; Maureille, Bruno; Semal, Patrick; Vanbrabant, Yves; Wood, Bernard

    2014-01-01

    Despite uncontested evidence for fossils belonging to the early hominin genus Australopithecus in East Africa from at least 4.2 million years ago (Ma), and from Chad by 3.5 Ma, thus far there has been no convincing evidence of Australopithecus, Paranthropus or early Homo from the western (Albertine) branch of the Rift Valley. Here we report the discovery of an isolated upper molar (#Ish25) from the Western Rift Valley site of Ishango in Central Africa in a derived context, overlying beds dated to between ca. 2.6 to 2.0 Ma. We used µCT imaging to compare its external and internal macro-morphology to upper molars of australopiths, and fossil and recent Homo. We show that the size and shape of the enamel-dentine junction (EDJ) surface discriminate between Plio-Pleistocene and post-Lower Pleistocene hominins, and that the Ishango molar clusters with australopiths and early Homo from East and southern Africa. A reassessment of the archaeological context of the specimen is consistent with the morphological evidence and suggest that early hominins were occupying this region by at least 2 Ma. PMID:24427292

  4. Hominin responses to environmental changes during the Middle Pleistocene in Central and Southern Italy

    NASA Astrophysics Data System (ADS)

    Orain, R.; Lebreton, V.; Russo Ermolli, E.; Sémah, A.-M.; Nomade, S.; Shao, Q.; Bahain, J.-J.; Thun Hohenstein, U.; Peretto, C.

    2012-10-01

    The palaeobotanical record of early Palaeolithic sites from Western Europe indicates that hominins settled in different kinds of environments. During the "Mid-Pleistocene Transition (MPT)", from about 1 to 0.6 Ma, the transition from 41-ka to 100-ka dominant climatic oscillations, occurring within a long-term cooling trend, was associated with an aridity crisis which strongly modified the ecosystems. Starting from the MPT the more favorable climate of central and southern Italy provided propitious environmental conditions for long-term human occupations even during the glacial times. In fact, the human strategy of territory occupation was certainly driven by the availabilities of resources. Prehistoric sites such as Notarchirico (ca. 680-600 ka), La Pineta (ca. 600-620 ka), Gaudo San Nicola (ca. 380-350 ka) or Ceprano (ca. 345-355 ka) testify to a preferential occupation of the central and southern Apennines valleys during interglacial phases, while later interglacial occupations were oriented towards the coastal plains, as attested by the numerous settlements of the Roma basin (ca. 300 ka). Faunal remains indicate that human subsistence behaviors benefited of a diversity of exploitable ecosystems, from semi-open to closed environments. In central and southern Italy, several palynological records have already illustrated the regional and local scale vegetation dynamic trends. During the Middle Pleistocene climate cycles, mixed mesophytic forests developed during the interglacial periods and withdrew in response to increasing aridity during the glacial episodes. New pollen data from the Boiano basin (Molise, Italy), attest to the evolution of vegetation and climate between OIS 13 and 9 (ca. 500 to 300 ka). In this basin, the persistence of high edaphic humidity, even during the glacial phases, could have favored the establishment of a refuge area for the arboreal flora and provided subsistence resources for the animal and hominin communities during the Middle

  5. Hominin responses to environmental changes during the Middle Pleistocene in central and southern Italy

    NASA Astrophysics Data System (ADS)

    Orain, R.; Lebreton, V.; Russo Ermolli, E.; Sémah, A.-M.; Nomade, S.; Shao, Q.; Bahain, J.-J.; Thun Hohenstein, U.; Peretto, C.

    2013-03-01

    The palaeobotanical record of early Palaeolithic sites from Western Europe indicates that hominins settled in different kinds of environments. During the "mid-Pleistocene transition (MPT)", from about 1 to 0.6 Ma, the transition from 41- to 100-ka dominant climatic oscillations, occurring within a long-term cooling trend, was associated with an aridity crisis which strongly modified the ecosystems. Starting from the MPT the more favourable climate of central and southern Italy provided propitious environmental conditions for long-term human occupations even during the glacial times. In fact, the human strategy of territory occupation was certainly driven by the availabilities of resources. Prehistoric sites such as Notarchirico (ca. 680-600 ka), La Pineta (ca. 600-620 ka), Guado San Nicola (ca. 380-350 ka) or Ceprano (ca. 345-355 ka) testify to a preferential occupation of the central and southern Apennines valleys during interglacial phases, while later interglacial occupations were oriented towards the coastal plains, as attested by the numerous settlements of the Roma Basin (ca. 300 ka). Faunal remains indicate that human subsistence behaviours benefited from a diversity of exploitable ecosystems, from semi-open to closed environments. In central and southern Italy, several palynological records have already illustrated the regional- and local-scale vegetation dynamic trends. During the Middle Pleistocene climate cycles, mixed mesophytic forests developed during the interglacial periods and withdrew in response to increasing aridity during the glacial episodes. New pollen data from the Boiano Basin (Molise, Italy) attest to the evolution of vegetation and climate between MIS 13 and 9 (ca. 500 to 300 ka). In this basin the persistence of high edaphic humidity, even during the glacial phases, could have favoured the establishment of a refuge area for the arboreal flora and provided subsistence resources for the animal and hominin communities during the Middle

  6. Middle Pliocene hominin mandibular fourth premolars from Woranso-Mille (Central Afar, Ethiopia).

    PubMed

    Haile-Selassie, Yohannes; Melillo, Stephanie M

    2015-01-01

    The Woranso-Mille study area has thus far yielded more than 120 early hominin fossil specimens dated to between 3.4 and 3.8 million years ago. Previous studies indicate that dentognathic fossil remains from the study area show a mosaic of features shared by both Australopithecus anamensis and Australopithecus afarensis. Here, we describe 12 isolated mandibular fourth premolars recovered from the Woranso-Mille study area and compare them with those of other early hominins using both traditional comparative methods and geometric morphometric methods. The results indicate that the Woranso-Mille sample is most similar to Au. afarensis among hominins. However, some specimens show distinctive features of crown shape, namely an extremely bulging distolingual corner associated with a relatively large talonid and a mesiodistally elongated crown. This unique morphology is accompanied by a root form that is different from those identified previously. The existence of distinctive P4 morphology is intriguing given the presence of more than one hominin species at Woranso-Mille, although support for taxonomic heterogeneity in this sample is equivocal. Further, the taxonomic significance of these features is unclear, as they fail to distinguish Pan from Gorilla and known hominin species from one another.

  7. Comparative morphological and morphometric description of the hominin calvaria from Bukuran (Sangiran, Central Java, Indonesia).

    PubMed

    Grimaud-Hervé, Dominique; Widianto, Harry; Détroit, Florent; Sémah, François

    2012-11-01

    We describe the hominin skull (called here "Bukuran") discovered in the lower Kabuh (or "Bapang") series near Sendangbusik, from the Bukuran area in the Sangiran dome. The fossil, heavily mineralized, consists of the parieto-occipital and the left temporal, and the frontal bones. When combined, those two cranial parts represent a rather complete and well-preserved calvaria. Its stratigraphic position was established after the discovery. A detailed description is presented of the morphological and metric features of the Bukuran calvaria, and comparisons are made with Asian Homo erectus from Indonesia and China. The estimated cranial capacity of Bukuran, the general shape of its cranial vault, its ectocranial structures, and its morphological and metrical characters are in the range of Asian Homo erectus, and show clear affinities with other Indonesian members of the species. We discuss the evolutionary status of the Bukuran calvaria and its implication for hominin history on Java.

  8. Late Acheulean hominins at the Marine Isotope Stage 6/5e transition in north-central India

    NASA Astrophysics Data System (ADS)

    Haslam, Michael; Roberts, Richard G.; Shipton, Ceri; Pal, J. N.; Fenwick, Jacqueline L.; Ditchfield, Peter; Boivin, Nicole; Dubey, A. K.; Gupta, M. C.; Petraglia, Michael

    2011-05-01

    Single-grain optically stimulated luminescence dating was applied to Late Quaternary sediments at two sites in the Middle Son Valley, Madhya Pradesh, India. Designated Bamburi 1 and Patpara, these sites contain Late Acheulean stone tool assemblages, which we associate with non-modern hominins. Age determinations of 140-120 ka place the formation of these sites at around the Marine Oxygen Isotope Stage 6-5 transition, placing them among the youngest Acheulean sites in the world. We present here the geochronology and sedimentological setting of these sites, and consider potential implications of Late Pleistocene archaic habitation in north-central India for the initial dispersal of modern humans across South Asia.

  9. Consistent C3 plant habitat of hominins during 400-300 ka at the Longyadong Cave site (Luonan Basin, central China) revealed by stable carbon isotope analyses of loess deposits

    NASA Astrophysics Data System (ADS)

    Zhang, Hongyan; Lu, Huayu; Wang, Shejiang

    2017-04-01

    The proportions of woody and grassland taxa in terrestrial ecosystems played an important role in the origin and evolution of early Palaeolithic hominins. However the influence of ecosystem changes on hominin behavior and adaptations in Asia has not been studied in detail. Hominins have exploited the Luonan Basin in the Eastern Qinling Mountains, central China, since the early Paleolithic. Dated sites, consisting of alternating loess and soil deposits with in situ artefacts, are common in the region, and provide a detailed record of Early to Middle Pleistocene hominin environments. Here, we present the results of measurements of the stable carbon isotopic composition of soil organic matter (δ13C) in the loess-paleosol sequences from the Longyadong Cave site. Our analyses of δ13C show that for at least 400 ka the Longyadong Cave site and its surroundings were dominated by C3 woody plants, whereas the nearby Liuwan site was dominated by C4 and C3 mixed grassland or woody grassland vegetation. These findings demonstrate that between 400 and 300 ka in the Luonan Basin, hominins occupied a habitat consisting of a mosaic of grassland and woodland/forest. Although the vegetation of the region changed in response to the glacial-interglacial climatic cycles, patches of woody vegetation in landscapes such as at Longyadong Cave site persisted continuously. Such environments seem to be have been favored by hominins living in the Luonan Basin, possibly because they provided a diverse range of food resources during both glacial and interglacial intervals of the Middle Pleistocene, when most of northern China was experiencing an increasing trend of drying and cooling and steppe environments were expanding. Thus, the Luonan Basin would have served as a refugium for hominin occupation in China during the Middle Pleistocene.

  10. Consistent C3 plant habitat of hominins during 400-300 ka at the Longyadong Cave site (Luonan Basin, central China) revealed by stable carbon isotope analyses of loess deposits.

    PubMed

    Zhang, Hongyan; Lu, Huayu; Wang, Shejiang; Zhang, Enlou; Cosgrove, Richard; Zhang, Wenchao; Li, Lu

    2017-07-01

    The proportions of woody and grassland taxa in terrestrial ecosystems played an important role in the origin and evolution of early Palaeolithic hominins. However the influence of ecosystem changes on hominin behavior and adaptations in Asia has not been studied in detail. Hominins have exploited the Luonan Basin in the Eastern Qinling Mountains, central China, since the early Paleolithic. Dated sites, consisting of alternating loess and soil deposits with in situ artefacts, are common in the region, and provide a detailed record of Early to Middle Pleistocene hominin environments. Here, we present the results of measurements of the stable carbon isotopic composition of soil organic matter (δ(13)CSOM) in the loess-paleosol sequences from the Longyadong Cave site. Our analyses of δ(13)CSOM show that for at least 400 ka the Longyadong Cave site and its surroundings were dominated by C3 woody plants, whereas the nearby Liuwan site was dominated by C4 and C3 mixed grassland or woody grassland vegetation. These findings demonstrate that between 400 and 300 ka in the Luonan Basin, hominins occupied a habitat consisting of a mosaic of grassland and woodland/forest. Although the vegetation of the region changed in response to the glacial-interglacial climatic cycles, patches of woody vegetation in landscapes such as at Longyadong Cave site persisted continuously. Such environments seem to be have been favored by hominins living in the Luonan Basin, possibly because they provided a diverse range of food resources during both glacial and interglacial intervals of the Middle Pleistocene, when most of northern China was experiencing an increasing trend of drying and cooling and steppe environments were expanding. Thus, the Luonan Basin would have served as a refugium for hominin occupation in China during the Middle Pleistocene. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Earliest Archaeological Evidence of Persistent Hominin Carnivory

    PubMed Central

    Ferraro, Joseph V.; Plummer, Thomas W.; Pobiner, Briana L.; Oliver, James S.; Bishop, Laura C.; Braun, David R.; Ditchfield, Peter W.; Seaman, John W.; Binetti, Katie M.; Seaman, John W.; Hertel, Fritz; Potts, Richard

    2013-01-01

    The emergence of lithic technology by ∼2.6 million years ago (Ma) is often interpreted as a correlate of increasingly recurrent hominin acquisition and consumption of animal remains. Associated faunal evidence, however, is poorly preserved prior to ∼1.8 Ma, limiting our understanding of early archaeological (Oldowan) hominin carnivory. Here, we detail three large well-preserved zooarchaeological assemblages from Kanjera South, Kenya. The assemblages date to ∼2.0 Ma, pre-dating all previously published archaeofaunas of appreciable size. At Kanjera, there is clear evidence that Oldowan hominins acquired and processed numerous, relatively complete, small ungulate carcasses. Moreover, they had at least occasional access to the fleshed remains of larger, wildebeest-sized animals. The overall record of hominin activities is consistent through the stratified sequence – spanning hundreds to thousands of years – and provides the earliest archaeological evidence of sustained hominin involvement with fleshed animal remains (i.e., persistent carnivory), a foraging adaptation central to many models of hominin evolution. PMID:23637995

  12. Tectonic uplift-influenced monsoonal changes promoted hominin occupation of the Luonan Basin: Insights from a loess-paleosol sequence, eastern Qinling Mountains, central China

    NASA Astrophysics Data System (ADS)

    Fang, Qian; Hong, Hanlie; Zhao, Lulu; Furnes, Harald; Lu, Huayu; Han, Wen; Liu, Yao; Jia, Zhuoyue; Wang, Chaowen; Yin, Ke; Algeo, Thomas J.

    2017-08-01

    Quaternary soil deposits from northern and southern China are distinctly different, reflecting variability of the East Asian monsoon north and south of the Qinling Mountains. Coeval sediments from the transitional climatic zone of central China, which are little studied to date, have the potential to improve our understanding of Quaternary monsoon changes and associated influences on hominin occupation of this region. Here, we investigate in detail a well-preserved and continuous Quaternary loess-paleosol sequence (Shangbaichuan) from the Luonan Basin, using a variety of weathering indices including major and trace element ratios, clay mineralogy, and Fe-oxide mineralogy. The whole-rock samples display similar rare earth element patterns characterized by upper continental crustal ratios: (La/Yb)N ≈ 9.5 and Eu/Eu* ≈ 0.65. Elemental data such as (La/Yb)N, La/Th and Eu/Eu* ratios show a high degree of homogeneity, suggesting that dust in the source region may have been thoroughly mixed and recycled, resulting in all samples having a uniform initial composition. Indices for pedogenic weathering such as Na/K, Ba/Sr, Rb/Sr, CIA, CIW, CPA, PIA, kaolinite/illite, (kaolinite + smectite)/illite, and hematite/(hematite + goethite) exhibit similar secular trends and reveal a four-stage accumulation history. The indices also indicate that the climate was warmer and wetter during the most recent interglacial stage, compared with coeval environments of the Chinese Loess Plateau. Secular changes in weathering intensity can be related to stepwise uplift of the Qinling Mountains and variation in East Asian monsoon intensity, both of which played significant roles in controlling climate evolution in the Luonan Basin. Furthermore, intensified aridity and winter monsoon strength in dust source areas, as evidenced by mineralogic and geochemical changes, may have been due to the mid-Pleistocene climate transition. Based on temporal correlation of warmer and wetter climatic conditions

  13. Unexpectedly many extinct hominins.

    PubMed

    Bokma, Folmer; van den Brink, Valentijn; Stadler, Tanja

    2012-09-01

    Recent studies indicate that Neanderthal and Denisova hominins may have been separate species, while debate continues on the status of Homo floresiensis. The decade-long debate between "splitters," who recognize over 20 hominin species, and "lumpers," who maintain that all these fossils belong to just a few lineages, illustrates that we do not know how many extinct hominin species to expect. Here, we present probability distributions for the number of speciation events and the number of contemporary species along a branch of a phylogeny. With estimates of hominin speciation and extincton rates, we then show that the expected total number of extinct hominin species is 8, but may be as high as 27. We also show that it is highly unlikely that three very recent species disappeared due to natural, background extinction. This may indicate that human-like remains are too easily considered distinct species. Otherwise, the evidence suggesting that Neanderthal and the Denisova hominin represent distinct species implies a recent wave of extinctions, ostensibly driven by the only survivor, H. sapiens. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  14. Early hominin auditory capacities.

    PubMed

    Quam, Rolf; Martínez, Ignacio; Rosa, Manuel; Bonmatí, Alejandro; Lorenzo, Carlos; de Ruiter, Darryl J; Moggi-Cecchi, Jacopo; Conde Valverde, Mercedes; Jarabo, Pilar; Menter, Colin G; Thackeray, J Francis; Arsuaga, Juan Luis

    2015-09-01

    Studies of sensory capacities in past life forms have offered new insights into their adaptations and lifeways. Audition is particularly amenable to study in fossils because it is strongly related to physical properties that can be approached through their skeletal structures. We have studied the anatomy of the outer and middle ear in the early hominin taxa Australopithecus africanus and Paranthropus robustus and estimated their auditory capacities. Compared with chimpanzees, the early hominin taxa are derived toward modern humans in their slightly shorter and wider external auditory canal, smaller tympanic membrane, and lower malleus/incus lever ratio, but they remain primitive in the small size of their stapes footplate. Compared with chimpanzees, both early hominin taxa show a heightened sensitivity to frequencies between 1.5 and 3.5 kHz and an occupied band of maximum sensitivity that is shifted toward slightly higher frequencies. The results have implications for sensory ecology and communication, and suggest that the early hominin auditory pattern may have facilitated an increased emphasis on short-range vocal communication in open habitats.

  15. Early hominin auditory capacities

    PubMed Central

    Quam, Rolf; Martínez, Ignacio; Rosa, Manuel; Bonmatí, Alejandro; Lorenzo, Carlos; de Ruiter, Darryl J.; Moggi-Cecchi, Jacopo; Conde Valverde, Mercedes; Jarabo, Pilar; Menter, Colin G.; Thackeray, J. Francis; Arsuaga, Juan Luis

    2015-01-01

    Studies of sensory capacities in past life forms have offered new insights into their adaptations and lifeways. Audition is particularly amenable to study in fossils because it is strongly related to physical properties that can be approached through their skeletal structures. We have studied the anatomy of the outer and middle ear in the early hominin taxa Australopithecus africanus and Paranthropus robustus and estimated their auditory capacities. Compared with chimpanzees, the early hominin taxa are derived toward modern humans in their slightly shorter and wider external auditory canal, smaller tympanic membrane, and lower malleus/incus lever ratio, but they remain primitive in the small size of their stapes footplate. Compared with chimpanzees, both early hominin taxa show a heightened sensitivity to frequencies between 1.5 and 3.5 kHz and an occupied band of maximum sensitivity that is shifted toward slightly higher frequencies. The results have implications for sensory ecology and communication, and suggest that the early hominin auditory pattern may have facilitated an increased emphasis on short-range vocal communication in open habitats. PMID:26601261

  16. New species from Ethiopia further expands Middle Pliocene hominin diversity.

    PubMed

    Haile-Selassie, Yohannes; Gibert, Luis; Melillo, Stephanie M; Ryan, Timothy M; Alene, Mulugeta; Deino, Alan; Levin, Naomi E; Scott, Gary; Saylor, Beverly Z

    2015-05-28

    Middle Pliocene hominin species diversity has been a subject of debate over the past two decades, particularly after the naming of Australopithecus bahrelghazali and Kenyanthropus platyops in addition to the well-known species Australopithecus afarensis. Further analyses continue to support the proposal that several hominin species co-existed during this time period. Here we recognize a new hominin species (Australopithecus deyiremeda sp. nov.) from 3.3-3.5-million-year-old deposits in the Woranso-Mille study area, central Afar, Ethiopia. The new species from Woranso-Mille shows that there were at least two contemporaneous hominin species living in the Afar region of Ethiopia between 3.3 and 3.5 million years ago, and further confirms early hominin taxonomic diversity in eastern Africa during the Middle Pliocene epoch. The morphology of Au. deyiremeda also reinforces concerns related to dentognathic (that is, jaws and teeth) homoplasy in Plio-Pleistocene hominins, and shows that some dentognathic features traditionally associated with Paranthropus and Homo appeared in the fossil record earlier than previously thought.

  17. Aridity and hominin environments

    NASA Astrophysics Data System (ADS)

    Blumenthal, Scott A.; Levin, Naomi E.; Brown, Francis H.; Brugal, Jean-Philip; Chritz, Kendra L.; Harris, John M.; Jehle, Glynis E.; Cerling, Thure E.

    2017-07-01

    Aridification is often considered a major driver of long-term ecological change and hominin evolution in eastern Africa during the Plio-Pleistocene; however, this hypothesis remains inadequately tested owing to difficulties in reconstructing terrestrial paleoclimate. We present a revised aridity index for quantifying water deficit (WD) in terrestrial environments using tooth enamel δ18O values, and use this approach to address paleoaridity over the past 4.4 million years in eastern Africa. We find no long-term trend in WD, consistent with other terrestrial climate indicators in the Omo-Turkana Basin, and no relationship between paleoaridity and herbivore paleodiet structure among fossil collections meeting the criteria for WD estimation. Thus, we suggest that changes in the abundance of C4 grass and grazing herbivores in eastern Africa during the Pliocene and Pleistocene may have been decoupled from aridity. As in modern African ecosystems, other factors, such as rainfall seasonality or ecological interactions among plants and mammals, may be important for understanding the evolution of C4 grass- and grazer-dominated biomes.

  18. Aridity and hominin environments.

    PubMed

    Blumenthal, Scott A; Levin, Naomi E; Brown, Francis H; Brugal, Jean-Philip; Chritz, Kendra L; Harris, John M; Jehle, Glynis E; Cerling, Thure E

    2017-07-11

    Aridification is often considered a major driver of long-term ecological change and hominin evolution in eastern Africa during the Plio-Pleistocene; however, this hypothesis remains inadequately tested owing to difficulties in reconstructing terrestrial paleoclimate. We present a revised aridity index for quantifying water deficit (WD) in terrestrial environments using tooth enamel δ(18)O values, and use this approach to address paleoaridity over the past 4.4 million years in eastern Africa. We find no long-term trend in WD, consistent with other terrestrial climate indicators in the Omo-Turkana Basin, and no relationship between paleoaridity and herbivore paleodiet structure among fossil collections meeting the criteria for WD estimation. Thus, we suggest that changes in the abundance of C4 grass and grazing herbivores in eastern Africa during the Pliocene and Pleistocene may have been decoupled from aridity. As in modern African ecosystems, other factors, such as rainfall seasonality or ecological interactions among plants and mammals, may be important for understanding the evolution of C4 grass- and grazer-dominated biomes.

  19. Dietary change among hominins and cercopithecids in Ethiopia during the early Pliocene

    PubMed Central

    Levin, Naomi E.; Haile-Selassie, Yohannes; Frost, Stephen R.; Saylor, Beverly Z.

    2015-01-01

    The incorporation of C4 resources into hominin diet signifies increased dietary breadth within hominins and divergence from the dietary patterns of other great apes. Morphological evidence indicates that hominin diet became increasingly diverse by 4.2 million years ago but may not have included large proportions of C4 foods until 800 thousand years later, given the available isotopic evidence. Here we use carbon isotope data from early to mid Pliocene hominin and cercopithecid fossils from Woranso-Mille (central Afar, Ethiopia) to constrain the timing of this dietary change and its ecological context. We show that both hominins and some papionins expanded their diets to include C4 resources as early as 3.76 Ma. Among hominins, this dietary expansion postdates the major dentognathic morphological changes that distinguish Australopithecus from Ardipithecus, but it occurs amid a continuum of adaptations to diets of tougher, harder foods and to committed terrestrial bipedality. In contrast, carbon isotope data from cercopithecids indicate that C4-dominated diets of the earliest members of the Theropithecus oswaldi lineage preceded the dental specialization for grazing but occurred after they were fully terrestrial. The combined data indicate that the inclusion of C4 foods in hominin diet occurred as part of broader ecological changes in African primate communities. PMID:26371308

  20. Dietary change among hominins and cercopithecids in Ethiopia during the early Pliocene

    NASA Astrophysics Data System (ADS)

    Levin, Naomi E.; Haile-Selassie, Yohannes; Frost, Stephen R.; Saylor, Beverly Z.

    2015-10-01

    The incorporation of C4 resources into hominin diet signifies increased dietary breadth within hominins and divergence from the dietary patterns of other great apes. Morphological evidence indicates that hominin diet became increasingly diverse by 4.2 million years ago but may not have included large proportions of C4 foods until 800 thousand years later, given the available isotopic evidence. Here we use carbon isotope data from early to mid Pliocene hominin and cercopithecid fossils from Woranso-Mille (central Afar, Ethiopia) to constrain the timing of this dietary change and its ecological context. We show that both hominins and some papionins expanded their diets to include C4 resources as early as 3.76 Ma. Among hominins, this dietary expansion postdates the major dentognathic morphological changes that distinguish Australopithecus from Ardipithecus, but it occurs amid a continuum of adaptations to diets of tougher, harder foods and to committed terrestrial bipedality. In contrast, carbon isotope data from cercopithecids indicate that C4-dominated diets of the earliest members of the Theropithecus oswaldi lineage preceded the dental specialization for grazing but occurred after they were fully terrestrial. The combined data indicate that the inclusion of C4 foods in hominin diet occurred as part of broader ecological changes in African primate communities.

  1. Dietary change among hominins and cercopithecids in Ethiopia during the early Pliocene.

    PubMed

    Levin, Naomi E; Haile-Selassie, Yohannes; Frost, Stephen R; Saylor, Beverly Z

    2015-10-06

    The incorporation of C4 resources into hominin diet signifies increased dietary breadth within hominins and divergence from the dietary patterns of other great apes. Morphological evidence indicates that hominin diet became increasingly diverse by 4.2 million years ago but may not have included large proportions of C4 foods until 800 thousand years later, given the available isotopic evidence. Here we use carbon isotope data from early to mid Pliocene hominin and cercopithecid fossils from Woranso-Mille (central Afar, Ethiopia) to constrain the timing of this dietary change and its ecological context. We show that both hominins and some papionins expanded their diets to include C4 resources as early as 3.76 Ma. Among hominins, this dietary expansion postdates the major dentognathic morphological changes that distinguish Australopithecus from Ardipithecus, but it occurs amid a continuum of adaptations to diets of tougher, harder foods and to committed terrestrial bipedality. In contrast, carbon isotope data from cercopithecids indicate that C4-dominated diets of the earliest members of the Theropithecus oswaldi lineage preceded the dental specialization for grazing but occurred after they were fully terrestrial. The combined data indicate that the inclusion of C4 foods in hominin diet occurred as part of broader ecological changes in African primate communities.

  2. Environmental hypotheses of hominin evolution.

    PubMed

    Potts, R

    1998-01-01

    The study of human evolution has long sought to explain major adaptations and trends that led to the origin of Homo sapiens. Environmental scenarios have played a pivotal role in this endeavor. They represent statements or, more commonly, assumptions concerning the adaptive context in which key hominin traits emerged. In many cases, however, these scenarios are based on very little if any data about the past settings in which early hominins lived. Several environmental hypotheses of human evolution are presented in this paper. Explicit test expectations are laid out, and a preliminary assessment of the hypotheses is made by examining the environmental records of Olduvai, Turkana, Olorgesailie, Zhoukoudian, Combe Grenal, and other hominin localities. Habitat-specific hypotheses have prevailed in almost all previous accounts of human adaptive history. The rise of African dry savanna is often cited as the critical event behind the development of terrestrial bipedality, stone toolmaking, and encephalized brains, among other traits. This savanna hypothesis has been countered recently by the woodland/forest hypothesis, which claims that Pliocene hominins had evolved in and were primarily attracted to closed habitats. The ideas that human evolution was fostered by cold habitats in higher latitudes or by seasonal variations in tropical and temperate zones also have their proponents. An alternative view, the variability selection hypothesis, states that large disparities in environmental conditions were responsible for important episodes of adaptive evolution. The resulting adaptations enhanced behavioral versatility and ultimately ecological diversity in the human lineage. Global environmental records for the late Cenozoic and specific records at hominin sites show the following: 1) early human habitats were subject to large-scale remodeling over time; 2) the evidence for environmental instability does not support habitat-specific explanations of key adaptive changes; 3

  3. Middle Pleistocene Hominin Teeth from Longtan Cave, Hexian, China

    PubMed Central

    Xing, Song; Martinón-Torres, María; Bermúdez de Castro, José María; Zhang, Yingqi; Fan, Xiaoxiao; Zheng, Longting; Huang, Wanbo; Liu, Wu

    2014-01-01

    Excavations at the Longtan Cave, Hexian, Anhui Province of Eastern China, have yielded several hominin fossils including crania, mandibular fragments, and teeth currently dated to 412±25 ka. While previous studies have focused on the cranial remains, there are no detailed analyses of the dental evidence. In this study, we provide metric and morphological descriptions and comparisons of ten teeth recovered from Hexian, including microcomputed tomography analyses. Our results indicate that the Hexian teeth are metrically and morphologically primitive and overlap with H. ergaster and East Asian Early and mid-Middle Pleistocene hominins in their large dimensions and occlusal complexities. However, the Hexian teeth differ from H. ergaster in features such as conspicuous vertical grooves on the labial/buccal surfaces of the central incisor and the upper premolar, the crown outline shapes of upper and lower molars and the numbers, shapes, and divergences of the roots. Despite their close geological ages, the Hexian teeth are also more primitive than Zhoukoudian specimens, and resemble Sangiran Early Pleistocene teeth. In addition, no typical Neanderthal features have been identified in the Hexian sample. Our study highlights the metrical and morphological primitive status of the Hexian sample in comparison to contemporaneous or even earlier populations of Asia. Based on this finding, we suggest that the primitive-derived gradients of the Asian hominins cannot be satisfactorily fitted along a chronological sequence, suggesting complex evolutionary scenarios with the coexistence and/or survival of different lineages in Eurasia. Hexian could represent the persistence in time of a H. erectus group that would have retained primitive features that were lost in other Asian populations such as Zhoukoudian or Panxian Dadong. Our study expands the metrical and morphological variations known for the East Asian hominins before the mid-Middle Pleistocene and warns about the

  4. Middle Pleistocene hominin teeth from Longtan Cave, Hexian, China.

    PubMed

    Xing, Song; Martinón-Torres, María; Bermúdez de Castro, José María; Zhang, Yingqi; Fan, Xiaoxiao; Zheng, Longting; Huang, Wanbo; Liu, Wu

    2014-01-01

    Excavations at the Longtan Cave, Hexian, Anhui Province of Eastern China, have yielded several hominin fossils including crania, mandibular fragments, and teeth currently dated to 412 ± 25 ka. While previous studies have focused on the cranial remains, there are no detailed analyses of the dental evidence. In this study, we provide metric and morphological descriptions and comparisons of ten teeth recovered from Hexian, including microcomputed tomography analyses. Our results indicate that the Hexian teeth are metrically and morphologically primitive and overlap with H. ergaster and East Asian Early and mid-Middle Pleistocene hominins in their large dimensions and occlusal complexities. However, the Hexian teeth differ from H. ergaster in features such as conspicuous vertical grooves on the labial/buccal surfaces of the central incisor and the upper premolar, the crown outline shapes of upper and lower molars and the numbers, shapes, and divergences of the roots. Despite their close geological ages, the Hexian teeth are also more primitive than Zhoukoudian specimens, and resemble Sangiran Early Pleistocene teeth. In addition, no typical Neanderthal features have been identified in the Hexian sample. Our study highlights the metrical and morphological primitive status of the Hexian sample in comparison to contemporaneous or even earlier populations of Asia. Based on this finding, we suggest that the primitive-derived gradients of the Asian hominins cannot be satisfactorily fitted along a chronological sequence, suggesting complex evolutionary scenarios with the coexistence and/or survival of different lineages in Eurasia. Hexian could represent the persistence in time of a H. erectus group that would have retained primitive features that were lost in other Asian populations such as Zhoukoudian or Panxian Dadong. Our study expands the metrical and morphological variations known for the East Asian hominins before the mid-Middle Pleistocene and warns about the

  5. Hominin Hip Biomechanics: Changing Perspectives.

    PubMed

    Warrener, Anna G

    2017-05-01

    The shape of the human pelvis reflects the unique demands placed on the hip abductor muscles (gluteus medius and gluteus minimus), which stabilize the body in the frontal plane during bipedal locomotion. This morphological shift occurred early in hominin evolution, yet important shape differences between hominin species have led to significant disagreement about abductor function and locomotor capability in these extinct taxa. A static biomechanical model that relies on a close association between skeletal measurements of the pelvis and femur has traditionally been used to reconstruct hip biomechanics in these species. However, experimental biomechanical approaches have highlighted the dynamic nature of mediolateral balance in walking and running, challenging the assumptions of the static hip model. This article reviews traditional approaches for understanding hip abductor function, shows how they have been applied to the fossil hominin record, and discusses new techniques that integrate the dynamic nature of mediolateral balance during human locomotion. Anat Rec, 300:932-945, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  6. Lumbar lordosis of extinct hominins.

    PubMed

    Been, Ella; Gómez-Olivencia, Asier; Kramer, Patricia A

    2012-01-01

    The lordotic curvature of the lumbar spine (lumbar lordosis) in humans is a critical component in the ability to achieve upright posture and bipedal gait. Only general estimates of the lordotic angle (LA) of extinct hominins are currently available, most of which are based on the wedging of the vertebral bodies. Recently, a new method for calculating the LA in skeletal material has become available. This method is based on the relationship between the lordotic curvature and the orientation of the inferior articular processes relative to vertebral bodies in the lumbar spines of living primates. Using this relationship, we developed new regression models in order to calculate the LAs in hominins. The new models are based on primate group-means and were used to calculate the LAs in the spines of eight extinct hominins. The results were also compared with the LAs of modern humans and modern nonhuman apes. The lordotic angles of australopithecines (41° ± 4), H. erectus (45°) and fossil H. sapiens (54° ± 14) are similar to those of modern humans (51° ± 11). This analysis confirms the assumption that human-like lordotic curvature was a morphological change that took place during the acquisition of erect posture and bipedalism as the habitual form of locomotion. Neandertals have smaller lordotic angles (LA = 29° ± 4) than modern humans, but higher angles than nonhuman apes (22° ± 3). This suggests possible subtle differences in Neandertal posture and locomotion from that of modern humans.

  7. Cranial base evolution within the hominin clade

    PubMed Central

    Nevell, L; Wood, B

    2008-01-01

    The base of the cranium (i.e. the basioccipital, the sphenoid and the temporal bones) is of particular interest because it undergoes significant morphological change within the hominin clade, and because basicranial morphology features in several hominin species diagnoses. We use a parsimony analysis of published cranial and dental data to predict the cranial base morphology expected in the hypothetical last common ancestor of the Pan–Homo clade. We also predict the primitive condition of the cranial base for the hominin clade, and document the evolution of the cranial base within the major subclades within the hominin clade. This analysis suggests that cranial base morphology has continued to evolve in the hominin clade, both before and after the emergence of the genus Homo. PMID:18380865

  8. Early hominin auditory ossicles from South Africa

    PubMed Central

    Quam, Rolf M.; de Ruiter, Darryl J.; Masali, Melchiorre; Arsuaga, Juan-Luis; Martínez, Ignacio; Moggi-Cecchi, Jacopo

    2013-01-01

    The middle ear ossicles are only rarely preserved in fossil hominins. Here, we report the discovery of a complete ossicular chain (malleus, incus, and stapes) of Paranthropus robustus as well as additional ear ossicles from Australopithecus africanus. The malleus in both early hominin taxa is clearly human-like in the proportions of the manubrium and corpus, whereas the incus and stapes resemble African and Asian great apes more closely. A deep phylogenetic origin is proposed for the derived malleus morphology, and this may represent one of the earliest human-like features to appear in the fossil record. The anatomical differences found in the early hominin incus and stapes, along with other aspects of the outer, middle, and inner ear, are consistent with the suggestion of different auditory capacities in these early hominin taxa compared with modern humans. PMID:23671079

  9. The hominin fossil record: taxa, grades and clades.

    PubMed

    Wood, Bernard; Lonergan, Nicholas

    2008-04-01

    This paper begins by reviewing the fossil evidence for human evolution. It presents summaries of each of the taxa recognized in a relatively speciose hominin taxonomy. These taxa are grouped in grades, namely possible and probable hominins, archaic hominins, megadont archaic hominins, transitional hominins, pre-modern Homo and anatomically modern Homo. The second part of this contribution considers some of the controversies that surround hominin taxonomy and systematics. The first is the vexed question of how you tell an early hominin from an early panin, or from taxa belonging to an extinct clade closely related to the Pan-Homo clade. Secondly, we consider how many species should be recognized within the hominin fossil record, and review the philosophies and methods used to identify taxa within the hominin fossil record. Thirdly, we examine how relationships within the hominin clade are investigated, including descriptions of the methods used to break down an integrated structure into tractable analytical units, and then how cladograms are generated and compared. We then review the internal structure of the hominin clade, including the problem of how many subclades should be recognized within the hominin clade, and we examine the reliability of hominin cladistic hypotheses. The last part of the paper reviews the concepts of a genus, including the criteria that should be used for recognizing genera within the hominin clade.

  10. The hominin fossil record: taxa, grades and clades

    PubMed Central

    Wood, Bernard; Lonergan, Nicholas

    2008-01-01

    This paper begins by reviewing the fossil evidence for human evolution. It presents summaries of each of the taxa recognized in a relatively speciose hominin taxonomy. These taxa are grouped in grades, namely possible and probable hominins, archaic hominins, megadont archaic hominins, transitional hominins, pre-modern Homo and anatomically modern Homo. The second part of this contribution considers some of the controversies that surround hominin taxonomy and systematics. The first is the vexed question of how you tell an early hominin from an early panin, or from taxa belonging to an extinct clade closely related to the Pan-Homo clade. Secondly, we consider how many species should be recognized within the hominin fossil record, and review the philosophies and methods used to identify taxa within the hominin fossil record. Thirdly, we examine how relationships within the hominin clade are investigated, including descriptions of the methods used to break down an integrated structure into tractable analytical units, and then how cladograms are generated and compared. We then review the internal structure of the hominin clade, including the problem of how many subclades should be recognized within the hominin clade, and we examine the reliability of hominin cladistic hypotheses. The last part of the paper reviews the concepts of a genus, including the criteria that should be used for recognizing genera within the hominin clade. PMID:18380861

  11. An aetiology of hominin behaviour.

    PubMed

    Bednarik, Robert G

    2012-10-01

    A rough framework for a first attempt to formulate a preliminary aetiology of hominin behaviour is proposed, based on scientific rather than archaeological evidence and reasoning. Distinctive precursors of modernity in human behaviour were present several million years ago, and since then have become gradually more established. By the beginning of the Middle Pleistocene, modern human cognitive processes seem to have been largely established. However, full modernity of behaviour can only have occurred in recent centuries, and there remain great variations in it even among extant conspecifics. This model differs significantly from all narratives offered by mainstream archaeology, which generally place the advent of modern human behaviour 30 or 40 millennia ago. These notions and the hypotheses they are based on appear to be false, however such behaviour is defined. Copyright © 2012 Elsevier GmbH. All rights reserved.

  12. Pliocene hominin biogeography and ecology.

    PubMed

    Macho, Gabriele A

    2015-10-01

    Australopithecus bahrelghazali, its origin and palaeobiology are not well understood. Reported from only one location some several thousand kilometres away from East African Pliocene hominin sites, it appears to have predominantly fed on C4 sources. Yet, it lacks the morphological adaptations of other primate C4 consumers like Paranthropus boisei and Theropithecus oswaldi. Furthermore, although considered to belong to Australopithecus afarensis by most researchers, A. bahrelghazali appears to differ from the former in a key aspect of its morphology: enamel thickness. To assess the phylogeny and palaeobiology of A. bahrelghazali, I first evaluate the dietary adaptations and energetics of A. bahrelghazali using empirical data of the feeding ecology of extant baboons, Papio cynocephalus. Information published on A. bahrelghazali morphology and habitat preference is used to select C4 foods with the appropriate mechanical properties and availability within the environment to create the models. By altering the feeding time on various food categories, I then test whether A. bahrelghazali could have subsisted on a C4 diet, thus accounting for the δ(13)C composition of its dental tissue. The effects of body mass on the volume of food consumed are taken into account. The outcomes of these simulations indicate that A. bahrelghazali could have subsisted on a diet of predominantly sedges, albeit with limitations. At higher energy requirements, i.e., above 3.5 times the BMR, it would be difficult for a medium-sized primate to obtain sufficient energy from a sedge-based diet. This is apparently due to constraints on foraging/feeding time, not because of the nutritional value of sedges per se. These results are discussed against the backdrop of A. bahrelghazali biogeography, palaeoenvironment, and phylogeny. The combined evidence makes it plausible to suggest that Northern Chad may have been a refugium for migrating mammals, including hominins, and throws new light on the deep

  13. Isotopic evidence of early hominin diets

    PubMed Central

    Sponheimer, Matt; Alemseged, Zeresenay; Cerling, Thure E.; Grine, Frederick E.; Kimbel, William H.; Leakey, Meave G.; Lee-Thorp, Julia A.; Manthi, Fredrick Kyalo; Reed, Kaye E.; Wood, Bernard A.; Wynn, Jonathan G.

    2013-01-01

    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.

  14. Isotopic evidence of early hominin diets

    NASA Astrophysics Data System (ADS)

    Sponheimer, Matt; Alemseged, Zeresenay; Cerling, Thure E.; Grine, Frederick E.; Kimbel, William H.; Leakey, Meave G.; Lee-Thorp, Julia A.; Kyalo Manthi, Fredrick; Reed, Kaye E.; Wood, Bernard A.; Wynn, Jonathan G.

    2013-06-01

    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.

  15. Locomotion and posture from the common hominoid ancestor to fully modern hominins, with special reference to the last common panin/hominin ancestor

    PubMed Central

    Crompton, R H; Vereecke, E E; Thorpe, S K S

    2008-01-01

    Based on our knowledge of locomotor biomechanics and ecology we predict the locomotion and posture of the last common ancestors of (a) great and lesser apes and their close fossil relatives (hominoids); (b) chimpanzees, bonobos and modern humans (hominines); and (c) modern humans and their fossil relatives (hominins). We evaluate our propositions against the fossil record in the context of a broader review of evolution of the locomotor system from the earliest hominoids of modern aspect (crown hominoids) to early modern Homo sapiens. While some early East African stem hominoids were pronograde, it appears that the adaptations which best characterize the crown hominoids are orthogrady and an ability to abduct the arm above the shoulder – rather than, as is often thought, manual suspension sensu stricto. At 7–9 Ma (not much earlier than the likely 4–8 Ma divergence date for panins and hominins, see Bradley, 2008) there were crown hominoids in southern Europe which were adapted to moving in an orthograde posture, supported primarily on the hindlimb, in an arboreal, and possibly for Oreopithecus, a terrestrial context. By 7 Ma, Sahelanthropus provides evidence of a Central African hominin, panin or possibly gorilline adapted to orthogrady, and both orthogrady and habitually highly extended postures of the hip are evident in the arboreal East African protohominin Orrorin at 6 Ma. If the traditional idea that hominins passed through a terrestrial ‘knuckle-walking’ phase is correct, not only does it have to be explained how a quadrupedal gait typified by flexed postures of the hindlimb could have preadapted the body for the hominin acquisition of straight-legged erect bipedality, but we would have to accept a transition from stem-hominoid pronogrady to crown hominoid orthogrady, back again to pronogrady in the African apes and then back to orthogrady in hominins. Hand-assisted arboreal bipedality, which is part of a continuum of orthograde behaviours, is used by

  16. Early hominin biogeography in Island Southeast Asia.

    PubMed

    Larick, Roy; Ciochon, Russell L

    2015-01-01

    Island Southeast Asia covers Eurasia's tropical expanse of continental shelf and active subduction zones. Cutting between island landmasses, Wallace's Line separates Sunda and the Eastern Island Arc (the Arc) into distinct tectonic and faunal provinces. West of the line, on Sunda, Java Island yields many fossils of Homo erectus. East of the line, on the Arc, Flores Island provides one skeleton and isolated remains of Homo floresiensis. Luzon Island in the Philippines has another fossil hominin. Sulawesi preserves early hominin archeology. This insular divergence sets up a unique regional context for early hominin dispersal, isolation, and extinction. The evidence is reviewed across three Pleistocene climate periods. Patterns are discussed in relation to the pulse of global sea-level shifts, as well as regional geo-tectonics, catastrophes, stegodon dispersal, and paleogenomics. Several patterns imply evolutionary processes typical of oceanic islands. Early hominins apparently responded to changing island conditions for a million-and-a-half years, likely becoming extinct during the period in which Homo sapiens colonized the region.

  17. Age and context of the oldest known hominin fossils from Flores.

    PubMed

    Brumm, Adam; van den Bergh, Gerrit D; Storey, Michael; Kurniawan, Iwan; Alloway, Brent V; Setiawan, Ruly; Setiyabudi, Erick; Grün, Rainer; Moore, Mark W; Yurnaldi, Dida; Puspaningrum, Mika R; Wibowo, Unggul P; Insani, Halmi; Sutisna, Indra; Westgate, John A; Pearce, Nick J G; Duval, Mathieu; Meijer, Hanneke J M; Aziz, Fachroel; Sutikna, Thomas; van der Kaars, Sander; Flude, Stephanie; Morwood, Michael J

    2016-06-09

    Recent excavations at the early Middle Pleistocene site of Mata Menge in the So'a Basin of central Flores, Indonesia, have yielded hominin fossils attributed to a population ancestral to Late Pleistocene Homo floresiensis. Here we describe the age and context of the Mata Menge hominin specimens and associated archaeological findings. The fluvial sandstone layer from which the in situ fossils were excavated in 2014 was deposited in a small valley stream around 700 thousand years ago, as indicated by (40)Ar/(39)Ar and fission track dates on stratigraphically bracketing volcanic ash and pyroclastic density current deposits, in combination with coupled uranium-series and electron spin resonance dating of fossil teeth. Palaeoenvironmental data indicate a relatively dry climate in the So'a Basin during the early Middle Pleistocene, while various lines of evidence suggest the hominins inhabited a savannah-like open grassland habitat with a wetland component. The hominin fossils occur alongside the remains of an insular fauna and a simple stone technology that is markedly similar to that associated with Late Pleistocene H. floresiensis.

  18. Hominin diversity in the Middle Pliocene of eastern Africa: the maxilla of KNM-WT 40000

    PubMed Central

    Spoor, Fred; Leakey, Meave G.; Leakey, Louise N.

    2010-01-01

    The 3.5-Myr-old hominin cranium KNM-WT 40000 from Lomekwi, west of Lake Turkana, has been assigned to a new hominin genus and species, Kenyanthropus platyops, on the basis of a unique combination of derived facial and primitive neurocranial features. Central to the diagnosis of K. platyops is the morphology of the maxilla, characterized by a flat and relatively orthognathic subnasal region, anteriorly placed zygomatic processes and small molars. To study this morphology in more detail, we compare the maxillae of African Plio-Pleistocene hominin fossils and samples of modern humans, chimpanzees and gorillas, using conventional and geometric morphometric methods. Computed tomography scans and detailed preparation of the KNM-WT 40000 maxilla enable comprehensive assessment of post-mortem changes, so that landmark data characterizing the morphology can be corrected for distortion. Based on a substantially larger comparative sample than previously available, the results of statistical analyses show that KNM-WT 40000 is indeed significantly different from and falls outside the known range of variation of species of Australopithecus and Paranthropus, contemporary Australopithecus afarensis in particular. These results support the attribution of KNM-WT 40000 to a separate species and the notion that hominin taxonomic diversity in Africa extends back well into the Middle Pliocene. PMID:20855311

  19. Hominin diversity in the Middle Pliocene of eastern Africa: the maxilla of KNM-WT 40000.

    PubMed

    Spoor, Fred; Leakey, Meave G; Leakey, Louise N

    2010-10-27

    The 3.5-Myr-old hominin cranium KNM-WT 40000 from Lomekwi, west of Lake Turkana, has been assigned to a new hominin genus and species, Kenyanthropus platyops, on the basis of a unique combination of derived facial and primitive neurocranial features. Central to the diagnosis of K. platyops is the morphology of the maxilla, characterized by a flat and relatively orthognathic subnasal region, anteriorly placed zygomatic processes and small molars. To study this morphology in more detail, we compare the maxillae of African Plio-Pleistocene hominin fossils and samples of modern humans, chimpanzees and gorillas, using conventional and geometric morphometric methods. Computed tomography scans and detailed preparation of the KNM-WT 40000 maxilla enable comprehensive assessment of post-mortem changes, so that landmark data characterizing the morphology can be corrected for distortion. Based on a substantially larger comparative sample than previously available, the results of statistical analyses show that KNM-WT 40000 is indeed significantly different from and falls outside the known range of variation of species of Australopithecus and Paranthropus, contemporary Australopithecus afarensis in particular. These results support the attribution of KNM-WT 40000 to a separate species and the notion that hominin taxonomic diversity in Africa extends back well into the Middle Pliocene.

  20. Hominin life history: reconstruction and evolution.

    PubMed

    Robson, Shannen L; Wood, Bernard

    2008-04-01

    In this review we attempt to reconstruct the evolutionary history of hominin life history from extant and fossil evidence. We utilize demographic life history theory and distinguish life history variables, traits such as weaning, age at sexual maturity, and life span, from life history-related variables such as body mass, brain growth, and dental development. The latter are either linked with, or can be used to make inferences about, life history, thus providing an opportunity for estimating life history parameters in fossil taxa. We compare the life history variables of modern great apes and identify traits that are likely to be shared by the last common ancestor of Pan-Homo and those likely to be derived in hominins. All great apes exhibit slow life histories and we infer this to be true of the last common ancestor of Pan-Homo and the stem hominin. Modern human life histories are even slower, exhibiting distinctively long post-menopausal life spans and later ages at maturity, pointing to a reduction in adult mortality since the Pan-Homo split. We suggest that lower adult mortality, distinctively short interbirth intervals, and early weaning characteristic of modern humans are derived features resulting from cooperative breeding. We evaluate the fidelity of three life history-related variables, body mass, brain growth and dental development, with the life history parameters of living great apes. We found that body mass is the best predictor of great ape life history events. Brain growth trajectories and dental development and eruption are weakly related proxies and inferences from them should be made with caution. We evaluate the evidence of life history-related variables available for extinct species and find that prior to the transitional hominins there is no evidence of any hominin taxon possessing a body size, brain size or aspects of dental development much different from what we assume to be the primitive life history pattern for the Pan-Homo clade. Data for

  1. Hominin life history: reconstruction and evolution

    PubMed Central

    Robson, Shannen L; Wood, Bernard

    2008-01-01

    In this review we attempt to reconstruct the evolutionary history of hominin life history from extant and fossil evidence. We utilize demographic life history theory and distinguish life history variables, traits such as weaning, age at sexual maturity, and life span, from life history-related variables such as body mass, brain growth, and dental development. The latter are either linked with, or can be used to make inferences about, life history, thus providing an opportunity for estimating life history parameters in fossil taxa. We compare the life history variables of modern great apes and identify traits that are likely to be shared by the last common ancestor of Pan-Homo and those likely to be derived in hominins. All great apes exhibit slow life histories and we infer this to be true of the last common ancestor of Pan-Homo and the stem hominin. Modern human life histories are even slower, exhibiting distinctively long post-menopausal life spans and later ages at maturity, pointing to a reduction in adult mortality since the Pan-Homo split. We suggest that lower adult mortality, distinctively short interbirth intervals, and early weaning characteristic of modern humans are derived features resulting from cooperative breeding. We evaluate the fidelity of three life history-related variables, body mass, brain growth and dental development, with the life history parameters of living great apes. We found that body mass is the best predictor of great ape life history events. Brain growth trajectories and dental development and eruption are weakly related proxies and inferences from them should be made with caution. We evaluate the evidence of life history-related variables available for extinct species and find that prior to the transitional hominins there is no evidence of any hominin taxon possessing a body size, brain size or aspects of dental development much different from what we assume to be the primitive life history pattern for the Pan-Homo clade. Data for

  2. Evolution of Spinopelvic Alignment in Hominins.

    PubMed

    Been, Ella; Gómez-Olivencia, Asier; Shefi, Sara; Soudack, Michalle; Bastir, Markus; Barash, Alon

    2017-05-01

    Spinopelvic alignment refers to the interaction between pelvic orientation, spinal curvatures, and the line of gravity. In a healthy modern human, this alignment is characterized by reciprocal curves/orientation of the sacrum, lumbar lordosis, thoracic kyphosis, and cervical lordosis. In an economic sagittal posture, these curvatures keep the line of gravity close to the center of the acetabulum. The purpose of this study is to explore the spinopelvic alignment in extinct hominins. We examined spinopelvic alignment of a single representative from each of the following hominin groups: Australopithecus, Homo erectus (H. erectus), H. neanderthalensis, and early H. sapiens. Pelvic incidence, lumbar lordosis, thoracic kyphosis, and cervical lordosis for each representative was estimated and compared with that of modern humans. Three basic spinopelvic alignments were found: (1) the sinusoidal alignment with moderate to high spinal curvatures and pelvic incidence found in H. erectus and H. sapiens; (2) the straight alignment with small spinal curvatures and small pelvic incidence found in Neandertal lineage hominins; (3) the compound alignment found in Australopithecus, with moderate pelvic incidence and lumbar lordosis, and nearly straight cervical spine. Our results indicate that balanced upright posture can be achieved in different alignments. Each hominin group solved the requirements of erect posture in a slightly different way. Moreover, we propose the term "cranio-spino-pelvic balance" to substitute "spino-pelvic balance." From an evolutionary perspective, not only changes in the pelvis have conditioned the evolution of the spinal curvatures but also changes in the equilibrium of the head likely also affected this balance. Anat Rec, 300:900-911, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  3. Tool making, hand morphology and fossil hominins

    PubMed Central

    Marzke, Mary W.

    2013-01-01

    Was stone tool making a factor in the evolution of human hand morphology? Is it possible to find evidence in fossil hominin hands for this capability? These questions are being addressed with increasingly sophisticated studies that are testing two hypotheses; (i) that humans have unique patterns of grip and hand movement capabilities compatible with effective stone tool making and use of the tools and, if this is the case, (ii) that there exist unique patterns of morphology in human hands that are consistent with these capabilities. Comparative analyses of human stone tool behaviours and chimpanzee feeding behaviours have revealed a distinctive set of forceful pinch grips by humans that are effective in the control of stones by one hand during manufacture and use of the tools. Comparative dissections, kinematic analyses and biomechanical studies indicate that humans do have a unique pattern of muscle architecture and joint surface form and functions consistent with the derived capabilities. A major remaining challenge is to identify skeletal features that reflect the full morphological pattern, and therefore may serve as clues to fossil hominin manipulative capabilities. Hominin fossils are evaluated for evidence of patterns of derived human grip and stress-accommodation features. PMID:24101624

  4. Prelinguistic evolution in early hominins: whence motherese?

    PubMed

    Falk, Dean

    2004-08-01

    In order to formulate hypotheses about the evolutionary underpinnings that preceded the first glimmerings of language, mother-infant gestural and vocal interactions are compared in chimpanzees and humans and used to model those of early hominins. These data, along with paleoanthropological evidence, suggest that prelinguistic vocal substrates for protolanguage that had prosodic features similar to contemporary motherese evolved as the trend for enlarging brains in late australopithecines/early Homo progressively increased the difficulty of parturition, thus causing a selective shift toward females that gave birth to relatively undeveloped neonates. It is hypothesized that hominin mothers adopted new foraging strategies that entailed maternal silencing, reassuring, and controlling of the behaviors of physically removed infants (i.e., that shared human babies' inability to cling to their mothers' bodies). As mothers increasingly used prosodic and gestural markings to encourage juveniles to behave and to follow, the meanings of certain utterances (words) became conventionalized. This hypothesis is based on the premises that hominin mothers that attended vigilantly to infants were strongly selected for, and that such mothers had genetically based potentials for consciously modifying vocalizations and gestures to control infants, both of which receive support from the literature.

  5. Was skin cancer a selective force for black pigmentation in early hominin evolution?

    PubMed Central

    Greaves, Mel

    2014-01-01

    Melanin provides a crucial filter for solar UV radiation and its genetically determined variation influences both skin pigmentation and risk of cancer. Genetic evidence suggests that the acquisition of a highly stable melanocortin 1 receptor allele promoting black pigmentation arose around the time of savannah colonization by hominins at some 1–2 Ma. The adaptive significance of dark skin is generally believed to be protection from UV damage but the pathologies that might have had a deleterious impact on survival and/or reproductive fitness, though much debated, are uncertain. Here, I suggest that data on age-associated cancer incidence and lethality in albinos living at low latitudes in both Africa and Central America support the contention that skin cancer could have provided a potent selective force for the emergence of black skin in early hominins. PMID:24573849

  6. Was skin cancer a selective force for black pigmentation in early hominin evolution?

    PubMed

    Greaves, Mel

    2014-04-22

    Melanin provides a crucial filter for solar UV radiation and its genetically determined variation influences both skin pigmentation and risk of cancer. Genetic evidence suggests that the acquisition of a highly stable melanocortin 1 receptor allele promoting black pigmentation arose around the time of savannah colonization by hominins at some 1-2 Ma. The adaptive significance of dark skin is generally believed to be protection from UV damage but the pathologies that might have had a deleterious impact on survival and/or reproductive fitness, though much debated, are uncertain. Here, I suggest that data on age-associated cancer incidence and lethality in albinos living at low latitudes in both Africa and Central America support the contention that skin cancer could have provided a potent selective force for the emergence of black skin in early hominins.

  7. The role of spatial foresight in models of hominin dispersal.

    PubMed

    Wren, Colin D; Xue, Julian Z; Costopoulos, Andre; Burke, Ariane

    2014-04-01

    Increasingly sophisticated hominin cognition is assumed to play an important role in major dispersal events but it is unclear what that role is. We present an agent-based model showing that there is a close relationship between level of foresight, environmental heterogeneity, and population dispersibility. We explore the dynamics between these three factors and discuss how they may affect the capacity of a hominin population to disperse. Generally, we find that high levels of environmental heterogeneity select for increased foresight and that high levels of foresight tend to reduce dispersibility. This suggests that cognitively complex hominins in heterogeneous environments have low dispersibility relative to cognitively less complex organisms in more homogeneous environments. The model predicts that the environments leading up to major episodes of dispersal, such as the initial hominin dispersal into Eurasia, were likely relatively low in spatial heterogeneity and that the dispersing hominins had relatively low foresight.

  8. Earliest hominin occupation of Sulawesi, Indonesia

    NASA Astrophysics Data System (ADS)

    van den Bergh, Gerrit D.; Li, Bo; Brumm, Adam; Grün, Rainer; Yurnaldi, Dida; Moore, Mark W.; Kurniawan, Iwan; Setiawan, Ruly; Aziz, Fachroel; Roberts, Richard G.; Suyono; Storey, Michael; Setiabudi, Erick; Morwood, Michael J.

    2016-01-01

    Sulawesi is the largest and oldest island within Wallacea, a vast zone of oceanic islands separating continental Asia from the Pleistocene landmass of Australia and Papua (Sahul). By one million years ago an unknown hominin lineage had colonized Flores immediately to the south, and by about 50 thousand years ago, modern humans (Homo sapiens) had crossed to Sahul. On the basis of position, oceanic currents and biogeographical context, Sulawesi probably played a pivotal part in these dispersals. Uranium-series dating of speleothem deposits associated with rock art in the limestone karst region of Maros in southwest Sulawesi has revealed that humans were living on the island at least 40 thousand years ago (ref. 5). Here we report new excavations at Talepu in the Walanae Basin northeast of Maros, where in situ stone artefacts associated with fossil remains of megafauna (Bubalus sp., Stegodon and Celebochoerus) have been recovered from stratified deposits that accumulated from before 200 thousand years ago until about 100 thousand years ago. Our findings suggest that Sulawesi, like Flores, was host to a long-established population of archaic hominins, the ancestral origins and taxonomic status of which remain elusive.

  9. Earliest hominin occupation of Sulawesi, Indonesia.

    PubMed

    van den Bergh, Gerrit D; Li, Bo; Brumm, Adam; Grün, Rainer; Yurnaldi, Dida; Moore, Mark W; Kurniawan, Iwan; Setiawan, Ruly; Aziz, Fachroel; Roberts, Richard G; Suyono; Storey, Michael; Setiabudi, Erick; Morwood, Michael J

    2016-01-14

    Sulawesi is the largest and oldest island within Wallacea, a vast zone of oceanic islands separating continental Asia from the Pleistocene landmass of Australia and Papua (Sahul). By one million years ago an unknown hominin lineage had colonized Flores immediately to the south, and by about 50 thousand years ago, modern humans (Homo sapiens) had crossed to Sahul. On the basis of position, oceanic currents and biogeographical context, Sulawesi probably played a pivotal part in these dispersals. Uranium-series dating of speleothem deposits associated with rock art in the limestone karst region of Maros in southwest Sulawesi has revealed that humans were living on the island at least 40 thousand years ago (ref. 5). Here we report new excavations at Talepu in the Walanae Basin northeast of Maros, where in situ stone artefacts associated with fossil remains of megafauna (Bubalus sp., Stegodon and Celebochoerus) have been recovered from stratified deposits that accumulated from before 200 thousand years ago until about 100 thousand years ago. Our findings suggest that Sulawesi, like Flores, was host to a long-established population of archaic hominins, the ancestral origins and taxonomic status of which remain elusive.

  10. Archeological insights into hominin cognitive evolution.

    PubMed

    Wynn, Thomas; Coolidge, Frederick L

    2016-07-01

    How did the human mind evolve? How and when did we come to think in the ways we do? The last thirty years have seen an explosion in research related to the brain and cognition. This research has encompassed a range of biological and social sciences, from epigenetics and cognitive neuroscience to social and developmental psychology. Following naturally on this efflorescence has been a heightened interest in the evolution of the brain and cognition. Evolutionary scholars, including paleoanthropologists, have deployed the standard array of evolutionary methods. Ethological and experimental evidence has added significantly to our understanding of nonhuman brains and cognition, especially those of nonhuman primates. Studies of fossil brains through endocasts and sophisticated imaging techniques have revealed evolutionary changes in gross neural anatomy. Psychologists have also gotten into the game through application of reverse engineering to experimentally based descriptions of cognitive functions. For hominin evolution, there is another rich source of evidence of cognition, the archeological record. Using the methods of Paleolithic archeology and the theories and models of cognitive science, evolutionary cognitive archeology documents developments in the hominin mind that would otherwise be inaccessible. © 2016 Wiley Periodicals, Inc.

  11. Morphological integration in the hominin dentition: evolutionary, developmental, and functional factors.

    PubMed

    Gómez-Robles, Aida; Polly, P David

    2012-04-01

    As the most common and best preserved remains in the fossil record, teeth are central to our understanding of evolution. However, many evolutionary analyses based on dental traits overlook the constraints that limit dental evolution. These constraints are diverse, ranging from developmental interactions between the individual elements of a homologous series (the whole dentition) to functional constraints related to occlusion. This study evaluates morphological integration in the hominin dentition and its effect on dental evolution in an extensive sample of Plio- and Pleistocene hominin teeth using geometric morphometrics and phylogenetic comparative methods. Results reveal that premolars and molars display significant levels of covariation; that integration is stronger in the mandibular dentition than in the maxillary dentition; and that antagonist teeth, especially first molars, are strongly integrated. Results also show an association of morphological integration and evolution. Stasis is observed in elements with strong functional and/or developmental interactions, namely in first molars. Alternatively, directional evolution (and weaker integration) occurs in the elements with marginal roles in occlusion and mastication, probably in response to other direct or indirect selective pressures. This study points to the need to reevaluate hypotheses about hominin evolution based on dental characters, given the complex scenario in which teeth evolve.

  12. Hominin occupations at the Dmanisi site, Georgia, Southern Caucasus: raw materials and technical behaviours of Europe's first hominins.

    PubMed

    Mgeladze, Ana; Lordkipanidze, David; Moncel, Marie-Hélène; Despriee, Jackie; Chagelishvili, Rusudan; Nioradze, Medea; Nioradze, Giorgi

    2011-05-01

    Dmanisi is the oldest site outside of Africa that records unquestioned hominin occupations as well as the dispersal of hominins in Europe and Asia. The site has yielded large numbers of artefacts from several periods of hominin occupation. This analysis of Dmanisi stone tool technology includes a review of all the pieces recovered during the last 15 years of excavations. This lithic assemblage gives insights into the hominin behaviour at 1.7-1.8 Ma in Eurasia. Dmanisi hominins exploited local rocks derived from either nearby riverbeds or outcrops, and petrographic study provides data on patterns of stone procurement. Recent geological surveys and technological studies of the artefacts illustrate the roles of hominins in composing the assemblage. Dmanisi hominins selected two types of blanks, including cobbles and angular blocks, of basalt, andesite, and tuffs. Many complete cobbles, pebbles, and rolled blocks in basalt were unmodified, and geological analyses and surveys indicate that hominins brought manuports back to the site, suggesting a complex procurement strategy. Cores, flakes and debris show that all stages of flaking activity took place at the site. Numerous unifacial cores suggest that knapping was not very elaborate. Centripetal knapping is observed on some flake-cores. Knapping was influenced by the blank shape and natural angles. Most flaked objects were either cores or chopper-cores. Flakes predominate while flake tools are rare. The Dmanisi lithic assemblage is comparable to Oldowan sites in Africa in terms of reduction sequence, organisation of the removals, platform types, and the lack of retouched flakes. Dmanisi artefacts and may have been produced by the original hominins in Europe and Asia.

  13. Correlates and catalysts of hominin evolution in Africa.

    PubMed

    McKee, Jeffrey K

    2017-06-09

    Hominin evolution in the African Pliocene and Pleistocene was accompanied and mediated by changes in the abiotic and biotic spheres. It has been hypothesized that such environmental changes were catalysts of hominin morphological evolution and speciations. Whereas there is little doubt that ecological changes were relevant to shaping the trajectories of mammalian evolution, testing specific hypotheses with data from the fossil record has yielded ambiguous results regarding environmental disruption as a primary catalyst. Proposed mechanisms for abiotic and biotic causes of evolution are not always consistent with the timing and trends exhibited by the African fossil record of hominins and other mammals. Analyses of fossil and genetic data suggest that much of hominin evolution, and by extension mammalian evolution, was autocatalytic, driven by feedback loops within a species or lineage, irrespective of changes in the external environment.

  14. Subduction, collision and initiation of hominin dispersal

    NASA Astrophysics Data System (ADS)

    Schattner, Uri; Lazar, Michael

    2009-09-01

    Subduction is the main driving force of plate tectonics controlling the physiography of the Earth. The northward subduction of the Sinai plate was interrupted during the Early Pleistocene when the Eratosthenes Seamount began to collide with the Cyprian arc. A series of synchronous structural deformations was triggered across the entire eastern Mediterranean, and local topography was drastically accentuation along the Levantine corridor - one of the main pathways of hominin dispersal out of Africa. However, the choice of this preferred pathway and timing of dispersal has not been resolved. Though causes for dispersal out of Africa are in debate, we show that the transition from subduction to collision in the eastern Mediterranean set the route.

  15. Protective buttressing of the hominin face.

    PubMed

    Carrier, David R; Morgan, Michael H

    2015-02-01

    When humans fight hand-to-hand the face is usually the primary target and the bones that suffer the highest rates of fracture are the parts of the skull that exhibit the greatest increase in robusticity during the evolution of basal hominins. These bones are also the most sexually dimorphic parts of the skull in both australopiths and humans. In this review, we suggest that many of the facial features that characterize early hominins evolved to protect the face from injury during fighting with fists. Specifically, the trend towards a more orthognathic face; the bunodont form and expansion of the postcanine teeth; the increased robusticity of the orbit; the increased robusticity of the masticatory system, including the mandibular corpus and condyle, zygoma, and anterior pillars of the maxilla; and the enlarged jaw adductor musculature are traits that may represent protective buttressing of the face. If the protective buttressing hypothesis is correct, the primary differences in the face of robust versus gracile australopiths may be more a function of differences in mating system than differences in diet as is generally assumed. In this scenario, the evolution of reduced facial robusticity in Homo is associated with the evolution of reduced strength of the upper body and, therefore, with reduced striking power. The protective buttressing hypothesis provides a functional explanation for the puzzling observation that although humans do not fight by biting our species exhibits pronounced sexual dimorphism in the strength and power of the jaw and neck musculature. The protective buttressing hypothesis is also consistent with observations that modern humans can accurately assess a male's strength and fighting ability from facial shape and voice quality.

  16. Energetic cost of walking in fossil hominins.

    PubMed

    Vidal-Cordasco, M; Mateos, A; Zorrilla-Revilla, G; Prado-Nóvoa, O; Rodríguez, J

    2017-08-19

    Many biomechanical studies consistently show that a broader pelvis increases the reaction forces and bending moments across the femoral shaft, increasing the energetic costs of unloaded locomotion. However, a biomechanical model does not provide the real amount of metabolic energy expended in walking. The aim of this study is to test the influence of pelvis breadth on locomotion cost and to evaluate the locomotion efficiency of extinct Pleistocene hominins. The current study measures in vivo the influence of pelvis width on the caloric cost of locomotion, integrating anthropometry, body composition and indirect calorimetry protocols in a sample of 46 subjects of both sexes. We show that a broader false pelvis is substantially more efficient for locomotion than a narrower one and that the influence of false pelvis width on the energetic cost is similar to the influence of leg length. Two models integrating body mass, femur length and bi-iliac breadth are used to estimate the net and gross energetic costs of locomotion in a number of extinct hominins. The results presented here show that the locomotion of Homo was not energetically more efficient than that of Australopithecus and that the locomotion of extinct Homo species was not less efficient than that of modern Homo sapiens. The changes in the anatomy of the pelvis and lower limb observed with the appearance of Homo ergaster probably did not fully offset the increased expenditure resulting from a larger body mass. Moreover, the narrow pelvis in modern humans does not contribute to greater efficiency of locomotion. © 2017 Wiley Periodicals, Inc.

  17. Rabbits and hominin survival in Iberia.

    PubMed

    Fa, John E; Stewart, John R; Lloveras, Lluís; Vargas, J Mario

    2013-04-01

    High dependence on the hunting and consumption of large mammals by some hominins may have limited their survival once their preferred quarry became scarce or disappeared. Adaptation to smaller residual prey would have been essential after the many large-bodied species decreased in numbers. We focus on the use of a superabundant species, the rabbit, to demonstrate the importance of this taxon in Iberia as fundamental to predators. We show that the use of the rabbit over time has increased, and that there could have been differential consumption by Neanderthals and Anatomically Modern Humans (AMH). Analysis of bone remains from excavations throughout Iberia show that this lagomorph was a crucial part of the diet of AMH but was relatively unutilised during the Mousterian, when Neanderthals were present. We first present changes in mammalian biomass and mean body mass of mammals over 50,000 years, to illustrate the dramatic loss of large mammalian fauna and to show how the rabbit may have contributed a consistently high proportion of the available game biomass throughout that period. Unlike the Italian Peninsula and other parts of Europe, in Iberia the rabbit has provided a food resource of great importance for predators including hominins. We suggest that hunters that could shift focus to rabbits and other smaller residual fauna, once larger-bodied species decreased in numbers, would have been able to persist. From the evidence presented here, we postulate that Neanderthals may have been less capable of prey-shifting and hence use the high-biomass prey resource provided by the rabbit, to the extent AMH did.

  18. Enamel thickness trends in Plio-Pleistocene hominin mandibular molars.

    PubMed

    Skinner, Matthew M; Alemseged, Zeresenay; Gaunitz, Charleen; Hublin, Jean-Jacques

    2015-08-01

    Enamel thickness continues to be an important morphological character in hominin systematics and is frequently invoked in dietary reconstructions of Plio-Pleistocene hominin taxa. However, to date, the majority of published data on molar enamel thickness of Pliocene and early Pleistocene hominins derive from naturally fractured random surfaces of a small number of specimens. In this study we systematically analyze enamel thickness in a large sample of Plio-Pleistocene fossil hominins (n = 99), extant hominoids (n = 57), and modern humans (n = 30). Based on analysis of 2D mesial planes of section derived from microtomography, we examine both average and relative enamel thickness, and the distribution of enamel across buccal, occlusal, and lingual components of mandibular molars. Our results confirm the trend of increasing enamel thickness during the Pliocene that culminates in the thick enamel of the robust Australopithecus species, and then decreases from early Homo to recent modern humans. All hominin taxa share a regional average enamel thickness pattern of thick occlusal enamel and greater buccal than lingual enamel thickness. Pan is unique in exhibiting the thinnest average enamel thickness in the occlusal basin. Statistical analysis indicates that among Pliocene hominins enamel thickness is a weak taxonomic discriminator. The data underlying these results are included in a table in the Supplementary Online Material. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Inferences regarding the diet of extinct hominins: structural and functional trends in dental and mandibular morphology within the hominin clade

    PubMed Central

    Lucas, Peter W; Constantino, Paul J; Wood, Bernard A

    2008-01-01

    This contribution investigates the evolution of diet in the Pan–Homo and hominin clades. It does this by focusing on 12 variables (nine dental and three mandibular) for which data are available about extant chimpanzees, modern humans and most extinct hominins. Previous analyses of this type have approached the interpretation of dental and gnathic function by focusing on the identification of the food consumed (i.e. fruits, leaves, etc.) rather than on the physical properties (i.e. hardness, toughness, etc.) of those foods, and they have not specifically addressed the role that the physical properties of foods play in determining dental adaptations. We take the available evidence for the 12 variables, and set out what the expression of each of those variables is in extant chimpanzees, the earliest hominins, archaic hominins, megadont archaic hominins, and an inclusive grouping made up of transitional hominins and pre-modern Homo. We then present hypotheses about what the states of these variables would be in the last common ancestor of the Pan–Homo clade and in the stem hominin. We review the physical properties of food and suggest how these physical properties can be used to investigate the functional morphology of the dentition. We show what aspects of anterior tooth morphology are critical for food preparation (e.g. peeling fruit) prior to its ingestion, which features of the postcanine dentition (e.g. overall and relative size of the crowns) are related to the reduction in the particle size of food, and how information about the macrostructure (e.g. enamel thickness) and microstructure (e.g. extent and location of enamel prism decussation) of the enamel cap might be used to make predictions about the types of foods consumed by extinct hominins. Specifically, we show how thick enamel can protect against the generation and propagation of cracks in the enamel that begin at the enamel–dentine junction and move towards the outer enamel surface. PMID:18380867

  20. Early hominin speciation at the Plio/Pleistocene transition.

    PubMed

    Cameron, D W

    2003-01-01

    Over the last half-decade or so, there has been an explosion in the recognition of hominin genera and species. We now have the late Miocene genera Orrorin and Sahelanthropus, the mid Pliocene genus Kenyanthropus, three new Pliocene species of Australopithecus (A. anamensis, A. garhi and A. bahrelghazali) and a sub species of Ardipithecus (Ar. r. kadabba) to contend with. Excepting also the more traditional species allocated to Paranthropus, Australopithecus and early Homo we are approaching around 15 species over 5 million years (excluding hominin evolution over the last one million years). Can such a large number of hominin species be justified? An examination of extant hominid (Gorilla gorilla, Pan troglodytes, and Pan paniscus) anatomical variability indicates that the range of fossil hominin variability supports the recognition of this large number of fossil species. It is also shown that not all hominins are directly related to the emergence of early Homo and as such have become extinct. Indeed the traditional australopithecine species 'A'. anamensis, 'A'. afarensis and 'A'. garhi are considered here to belong to a distinct genus Praeanthropus. They are also argued not be hominins, but rather an as yet undefined hominid group from which the more derived hominins evolved. The first hominin is represented by A. africanus or a hominin very much like it. The Paranthropus clade is defined by a derived heterochronic condition of peramorphosis, associated with sequential progenesis (contraction of successive growth stages) in brain and dental development, but a mixture of peramorphic and paedomorphic features in its craniofacial anatomy. Conversely, Kenyanthropus and Homo both share a pattern of peramorphosis, associated with sequential hypermorphosis (prolongation of successive growth stages) in brain development, and paedomorphosis processes in cranial, facial and dental development. This suggests, that these two clades share an important synapomorphy not

  1. Hominin evolution and gene flow in the Pleistocene Africa.

    PubMed

    Ovchinnikov, Igor V

    2013-01-01

    Africa demonstrates a complex process of the hominin evolution with a series of adaptive radiations during several millions of years that led to diverse morphological forms. Recently, Hammer et al. (2011) and Harvati et al. (2011) provided integrated morphological and genetic evidence of interbreeding between modern humans and unknown archaic hominins in Africa as recently as 35,000 years ago. However, a genetic evidence of hybridization between hominin lineages during the Lower and Middle Pleistocene epochs is unknown and the direct retrieval of DNA from extinct lineages of African hominins remains elusive. The availability of both nuclear and mitochondrial genome sequences from modern humans, Neanderthals, and Denisovans allows collecting nuclear DNA sequences of mitochondrial origin (numts) inserted into the nuclear genome of the ancestral hominin lineages and drawing conclusions about the hominin evolution in the remote past. The mtDNA and numt analysis uncovered a deep division of mtDNA lineages that existed in African hominins in the Middle Pleistocene. The first cluster included the human and Neanderthal-like mtDNA sequences while the second consisted of DNA sequences that are known today as mtAncestor-1, a nuclear fossil of the mtDNA, and the Denisova mtDNA isolated from a bone and a tooth found in southern Siberia. The two groups initially diverged 610,000-1,110,000 years ago. Approximately 220,000 years after the primary split, the Denisova - mtAncestor-1 mtDNA lineages mixed with the mtDNA pool of an ancestral population of Neanderthals and modern humans. This admixture after the profound division is demonstrated by the transposition of the Denisova-like mtDNA sequence into the nuclear genome of an ancestor of Neanderthals and modern humans. This finding suggests the matrilineal genetic structure among the Middle Pleistocene hominins as well as the existence of gene flow between African hominin lineages. Through paleogenomic analyses, it is impossible to

  2. Can hominin 'handedness' be accurately assessed?

    PubMed

    Cashmore, Lisa

    2009-01-01

    The expression of a strong, population-level right hand preference has, to date only been unequivocally identified in Homo sapiens and is often considered to be unique to this species. For this reason, and because of purported co-evolutionary links between this trait and language capabilities in modern humans, the identification of hand preference in the hominin fossil record has long been of interest to researchers studying the evolution of 'handedness' within the genus Homo. Identifying hand preference in skeletal samples, however, is not straightforward. Problems arise from difficulties in determining the precise nature of the relationship between hand use and bone morphology, the methods by which hand preference is assessed, the paucity of material available for study, and even what is meant by the term 'handedness'. Various attempts have been made to address these issues, encompassing a range of methodological approaches, such as comparisons of osteological techniques, studies of prehistoric material culture and ethnographic analysis of hand use behaviours in modern hunter-gatherer societies and non-human primate groups. What such research suggests is that hand preference is a complex phenomenon, in both extant and extinct groups, and in order to assess its expression in extinct populations care must be paid to the questions asked of the available material and the methodologies used to answer them.

  3. Does Environmental Knowledge Inhibit Hominin Dispersal?

    PubMed

    Wren, Colin D; Costopoulos, Andre

    2015-07-01

    We investigated the relationship between the dispersal potential of a hominin population, its local-scale foraging strategies, and the characteristics of the resource environment using an agent-based modeling approach. In previous work we demonstrated that natural selection can favor a relatively low capacity for assessing and predicting the quality of the resource environment, especially when the distribution of resources is highly clustered. That work also suggested that the more knowledge foraging populations had about their environment, the less likely they were to abandon the landscape they know and disperse into novel territory. The present study gives agents new individual and social strategies for learning about their environment. For both individual and social learning, natural selection favors decreased levels of environmental knowledge, particularly in low-heterogeneity environments. Social acquisition of detailed environmental knowledge results in crowding of agents, which reduces available reproductive space and relative fitness. Agents with less environmental knowledge move away from resource clusters and into areas with more space available for reproduction. These results suggest that, rather than being a requirement for successful dispersal, environmental knowledge strengthens the ties to particular locations and significantly reduces the dispersal potential as a result. The evolved level of environmental knowledge in a population depends on the characteristics of the resource environment and affects the dispersal capacity of the population.

  4. Stable isotope-based diet reconstructions of Turkana Basin hominins

    PubMed Central

    Cerling, Thure E.; Manthi, Fredrick Kyalo; Mbua, Emma N.; Leakey, Louise N.; Leakey, Meave G.; Leakey, Richard E.; Brown, Francis H.; Grine, Frederick E.; Hart, John A.; Kaleme, Prince; Roche, Hélène; Uno, Kevin T.; Wood, Bernard A.

    2013-01-01

    Hominin fossil evidence in the Turkana Basin in Kenya from ca. 4.1 to 1.4 Ma samples two archaic early hominin genera and records some of the early evolutionary history of Paranthropus and Homo. Stable carbon isotopes in fossil tooth enamel are used to estimate the fraction of diet derived from C3 or C4 resources in these hominin taxa. The earliest hominin species in the Turkana Basin, Australopithecus anamensis, derived nearly all of its diet from C3 resources. Subsequently, by ca. 3.3 Ma, the later Kenyanthropus platyops had a very wide dietary range—from virtually a purely C3 resource-based diet to one dominated by C4 resources. By ca. 2 Ma, hominins in the Turkana Basin had split into two distinct groups: specimens attributable to the genus Homo provide evidence for a diet with a ca. 65/35 ratio of C3- to C4-based resources, whereas P. boisei had a higher fraction of C4-based diet (ca. 25/75 ratio). Homo sp. increased the fraction of C4-based resources in the diet through ca. 1.5 Ma, whereas P. boisei maintained its high dependency on C4-derived resources. PMID:23733966

  5. Dental and skeletal growth in early fossil hominins.

    PubMed

    Dean, M Christopher; Lucas, Victoria S

    2009-01-01

    Early fossil hominins have often been assigned a chronological age on the basis of modern human data for tooth eruption. Better data and more sophisticated methods are now available to estimate their chronological age from modern human standards for stages of mineralization of individual teeth developing within the jaws. However, while comparisons with modern human dentitions are interesting, they can also be misleading as early hominin teeth and dentitions did not grow like modern human teeth. Chronological age can also be estimated using the microanatomy of tooth enamel and root dentine. Counts of incremental markings in enamel predict much younger ages at death for early fossil hominins than those based on modern human radiographic standards of dental development. Comparative evidence from the skeleton suggests that a greater proportion of adult body mass and stature was achieved earlier in the growth period of fossil hominins than it is in modern humans. The combined skeleto-dental evidence provides the basis for a hypothesis that the earliest hominins grew more like modern great apes, but that Homo erectus had a slightly more prolonged period of growth, and which was still not totally modern human-like in its pattern or timing.

  6. Stable isotope-based diet reconstructions of Turkana Basin hominins

    NASA Astrophysics Data System (ADS)

    Cerling, Thure E.; Kyalo Manthi, Fredrick; Mbua, Emma N.; Leakey, Louise N.; Leakey, Meave G.; Leakey, Richard E.; Brown, Francis H.; Grine, Frederick E.; Hart, John A.; Kaleme, Prince; Roche, Hélène; Uno, Kevin T.; Wood, Bernard A.

    2013-06-01

    Hominin fossil evidence in the Turkana Basin in Kenya from ca. 4.1 to 1.4 Ma samples two archaic early hominin genera and records some of the early evolutionary history of Paranthropus and Homo. Stable carbon isotopes in fossil tooth enamel are used to estimate the fraction of diet derived from C3 or C4 resources in these hominin taxa. The earliest hominin species in the Turkana Basin, Australopithecus anamensis, derived nearly all of its diet from C3 resources. Subsequently, by ca. 3.3 Ma, the later Kenyanthropus platyops had a very wide dietary range-from virtually a purely C3 resource-based diet to one dominated by C4 resources. By ca. 2 Ma, hominins in the Turkana Basin had split into two distinct groups: specimens attributable to the genus Homo provide evidence for a diet with a ca. 65/35 ratio of C3- to C4-based resources, whereas P. boisei had a higher fraction of C4-based diet (ca. 25/75 ratio). Homo sp. increased the fraction of C4-based resources in the diet through ca. 1.5 Ma, whereas P. boisei maintained its high dependency on C4-derived resources.

  7. Stable isotope-based diet reconstructions of Turkana Basin hominins.

    PubMed

    Cerling, Thure E; Manthi, Fredrick Kyalo; Mbua, Emma N; Leakey, Louise N; Leakey, Meave G; Leakey, Richard E; Brown, Francis H; Grine, Frederick E; Hart, John A; Kaleme, Prince; Roche, Hélène; Uno, Kevin T; Wood, Bernard A

    2013-06-25

    Hominin fossil evidence in the Turkana Basin in Kenya from ca. 4.1 to 1.4 Ma samples two archaic early hominin genera and records some of the early evolutionary history of Paranthropus and Homo. Stable carbon isotopes in fossil tooth enamel are used to estimate the fraction of diet derived from C3 or C4 resources in these hominin taxa. The earliest hominin species in the Turkana Basin, Australopithecus anamensis, derived nearly all of its diet from C3 resources. Subsequently, by ca. 3.3 Ma, the later Kenyanthropus platyops had a very wide dietary range--from virtually a purely C3 resource-based diet to one dominated by C4 resources. By ca. 2 Ma, hominins in the Turkana Basin had split into two distinct groups: specimens attributable to the genus Homo provide evidence for a diet with a ca. 65/35 ratio of C3- to C4-based resources, whereas P. boisei had a higher fraction of C4-based diet (ca. 25/75 ratio). Homo sp. increased the fraction of C4-based resources in the diet through ca. 1.5 Ma, whereas P. boisei maintained its high dependency on C4-derived resources.

  8. Comparative context of Plio-Pleistocene hominin brain evolution.

    PubMed

    Elton, S; Bishop, L C; Wood, B

    2001-07-01

    One of the distinguishing features of Homo sapiens is its absolutely and relatively large brain. This feature is also seen in less extreme form in some fossil Homo species. However, are increases in brain size during the Plio-Pleistocene only seen in Homo, and is brain enlargement among Plio-Pleistocene primates confined to hominins? This study examines evidence for changes in brain size for species and lineage samples of three synchronic East African fossil primate groups, the two hominin genera Homo and Paranthropus, and the cercopithecoid genus Theropithecus. Hominin endocranial capacity data were taken from the literature, but it was necessary to develop an indirect method for estimating the endocranial volume of Theropithecus. Bivariate and multivariate regression equations relating measured endocranial volume to three external cranial dimensions were developed from a large (ca. 340) sample of modern African cercopithecoids. These equations were used to estimate the endocranial volumes of 20 Theropithecus specimens from the African Plio-Pleistocene. Spearman's rho and the Hubert nonparametric test were used to search for evidence of temporal trends in both the hominin and Theropithecus data. Endocranial volume apparently increased over time in both Homo and Paranthropus boisei, but there was no evidence for temporal trends in the endocranial volume of Theropithecus. Thus, hypotheses which suggest a mix of environmental, social, dietary, or other factors as catalysts for increasing brain in Plio-Pleistocene primates must accommodate evidence of brain enlargement in both Homo and Paranthropus, and explain why this phenomenon appears to be restricted to hominins.

  9. Dental evidence on the hominin dispersals during the Pleistocene

    PubMed Central

    Martinón-Torres, M.; Bermúdez de Castro, J. M.; Gómez-Robles, A.; Arsuaga, J. L.; Carbonell, E.; Lordkipanidze, D.; Manzi, G.; Margvelashvili, A.

    2007-01-01

    A common assumption in the evolutionary scenario of the first Eurasian hominin populations is that they all had an African origin. This assumption also seems to apply for the Early and Middle Pleistocene populations, whose presence in Europe has been largely explained by a discontinuous flow of African emigrant waves. Only recently, some voices have speculated about the possibility of Asia being a center of speciation. However, no hard evidence has been presented to support this hypothesis. We present evidence from the most complete and up-to-date analysis of the hominin permanent dentition from Africa and Eurasia. The results show important morphological differences between the hominins found in both continents during the Pleistocene, suggesting that their evolutionary courses were relatively independent. We propose that the genetic impact of Asia in the colonization of Europe during the Early and Middle Pleistocene was stronger than that of Africa. PMID:17684093

  10. Lucy's Flat Feet: The Relationship between the Ankle and Rearfoot Arching in Early Hominins

    PubMed Central

    2010-01-01

    Background In the Plio-Pleistocene, the hominin foot evolved from a grasping appendage to a stiff, propulsive lever. Central to this transition was the development of the longitudinal arch, a structure that helps store elastic energy and stiffen the foot during bipedal locomotion. Direct evidence for arch evolution, however, has been somewhat elusive given the failure of soft-tissue to fossilize. Paleoanthropologists have relied on footprints and bony correlates of arch development, though little consensus has emerged as to when the arch evolved. Methodology/Principal Findings Here, we present evidence from radiographs of modern humans (n = 261) that the set of the distal tibia in the sagittal plane, henceforth referred to as the tibial arch angle, is related to rearfoot arching. Non-human primates have a posteriorly directed tibial arch angle, while most humans have an anteriorly directed tibial arch angle. Those humans with a posteriorly directed tibial arch angle (8%) have significantly lower talocalcaneal and talar declination angles, both measures of an asymptomatic flatfoot. Application of these results to the hominin fossil record reveals that a well developed rearfoot arch had evolved in Australopithecus afarensis. However, as in humans today, Australopithecus populations exhibited individual variation in foot morphology and arch development, and “Lucy” (A.L. 288-1), a 3.18 Myr-old female Australopithecus, likely possessed asymptomatic flat feet. Additional distal tibiae from the Plio-Pleistocene show variation in tibial arch angles, including two early Homo tibiae that also have slightly posteriorly directed tibial arch angles. Conclusions/Significance This study finds that the rearfoot arch was present in the genus Australopithecus. However, the female Australopithecus afarensis “Lucy” has an ankle morphology consistent with non-pathological flat-footedness. This study suggests that, as in humans today, there was variation in arch development

  11. When mothers need others: The impact of hominin life history evolution on cooperative breeding.

    PubMed

    Kramer, Karen L; Otárola-Castillo, Erik

    2015-07-01

    The evolution of cooperative breeding is particularly complex in humans because many other traits that directly affect parental care (shorter birth intervals, increased offspring survivorship, juvenile dependence, and older ages at dispersal) also emerge during the Pleistocene. If human cooperative breeding is ancient, it likely evolved in a hominin lacking a fully modern life history. However, the impact that changing life history traits has on parental care and cooperative breeding has not been analytically investigated. We develop an exploratory model to simulate an economic problem that would have arisen over the course of hominin life history evolution to identify those transitions that produced the strongest pressures for cooperative childrearing. The model generates two central predictions. First, help within maternal-offspring groups can support early changes in juvenile dependence, dispersal age, birth intervals, and fertility. If so, maternal-juvenile cooperation may be an important but understudied step in the evolution of human cooperative breeding. Second, pressure to recruit adult cooperation is most pronounced under more derived conditions of late dispersal and later ages of juvenile dependence, with a strong interaction at short birth intervals. Our findings indicate that changes in life history traits that affect parental care are critical in considering background selective forces that shaped the evolution of cooperative breeding.

  12. Possible paleohydrologic and paleoclimatic effects on hominin migration and occupation of the Levantine Middle Paleolithic.

    PubMed

    Frumkin, Amos; Bar-Yosef, Ofer; Schwarcz, Henry P

    2011-04-01

    This paper explores the impact of major glacial/interglacial paleohydrologic variations in the Middle-Paleolithic Levant on hominin migration and occupation. The climatic reconstruction is based primarily on the most straight-forward paleohydrologic records recently published. These terrestrial proxies convey direct paleoenvironmental signals of effective precipitation and aquifer recharge. The two main proxies are temporal changes of terminal lake levels in the Dead Sea basin and periods of deposition or non-deposition of speleothems. Other records, such as stable isotopes, if interpreted correctly, correspond well with these two direct proxies. All the records consistently indicate that the last two glacial periods in the central Levant were generally wet and cool, while the last two interglacials were dry and warm, so more water was available for the ecosystem and thus hominins during glacial periods than during interglacials. Some proxies indicate that the higher precipitation/evaporation ratio during glacial periods involved higher precipitation rather than only reduced evaporation. Beyond the general mean glacial/interglacial climate suggested here, variations occurred at all temporal scales throughout glacial or interglacial periods. In the Sahara-Negev arid barrier, moister conditions occurred during Marine Isotope Stage (MIS) 6a-5e, when Anatomically Modern Humans apparently migrated out of Africa. We suggest that this migration, as well as the later Neanderthal expansion from Southeast Europe or the Anatolian plateau into the Levant during early MIS 4, could be facilitated by the observed major climatic variations.

  13. Tephrochronology of the East African Baringo-Tugen Hills Cores: Hominin Sites and Paleolakes Drilling Project (HSPDP)

    NASA Astrophysics Data System (ADS)

    Garello, D.; Deino, A. L.; Campisano, C. J.; Kingston, J.; Arrowsmith, R.; Hill, A.

    2015-12-01

    The Baringo/Tugen Hills basin (BTB) in central Kenya is one of five Hominin Sites and Paleolakes Drilling Project (HSPDP) localities targeting lacustrine sediments associated with key fossil hominin sites. The fossiliferous Plio-Pliestocene Chemeron Formation, within the BTB, contains geochemically analyzed outcrop tephras, 8 of which have 40Ar/39Ar dates of 3.2-2.35Ma. Tephras have been crucial in developing chronologies in human evolution, paleontology, archaeology, and rift basin development. The HSPDP paleo-lake cores provide a high resolution and continuous record of sedimentation, as well as additional tephras not found in outcrop. For BTB, approximately 20 vitric tephras have been logged in the cores, including several previously unobserved tephras, providing a more complete record of volcanic activity. Major element geochemical analyses of the BTB tephras collected from the cores are critical for establishing chronostratigraphic links to the outcrop stratigraphy of the Chemeron Formation, as well as correlations outside of BTB. The Chemeron Formation, composed of alternating fluvial and lacustrine sediments, is associated with the onset and intensification of the Cenozoic Northern Hemisphere glaciation and encompasses the period of great hominin diversification of Paranthropus and Homo, as well as the earliest evidence for stone toolmaking. Within the Chemeron stratigraphy, there are sequences of diatomites that record a 23kyr-processional periodicity indicating a dominant climatic forcing. By correlating the BTB tephras, and thereby the BTB climate-forced lacustrine cycles, with other East African rift basins' stratigraphy, we can determine if this climatic wet/dry pattern observed at BTB had occurred in other East African rift basins. This knowledge can help in understanding the influence of climate and tectonics on the evolution of hominins during the Plio-Pleistocene.

  14. Interpreting sulci on hominin endocasts: old hypotheses and new findings

    PubMed Central

    Falk, Dean

    2014-01-01

    Paleoneurologists analyze internal casts (endocasts) of fossilized braincases, which provide information about the size, shape and, to a limited degree, sulcal patterns reproduced from impressions left by the surface of the brain. When interpreted in light of comparative data from the brains of living apes and humans, sulcal patterns reproduced on hominin endocasts provide important information for studying the evolution of the cerebral cortex and cognition in human ancestors. Here, new evidence is discussed for the evolution of sulcal patterns associated with cortical reorganization in three parts of the hominin brain: (1) the parietotemporo-occipital association cortex, (2) Broca's speech area, and (3) dorsolateral prefrontal association cortex. Of the three regions, the evidence regarding the last is the clearest. Compared to great apes, Australopithecus endocasts reproduce a clear middle frontal sulcus in the dorsolateral prefrontal cortex that is derived toward the human condition. This finding is consistent with data from comparative cytoarchitectural studies of ape and human brains as well as shape analyses of australopithecine endocasts. The comparative and direct evidence for all three regions suggests that hominin brain reorganization was underway by at least the time of Australopithecus africanus (~2.5 to 3.0 mya), despite the ape-sized brains of these hominins, and that it entailed expansion of both rostral and caudal association cortices. PMID:24822043

  15. New Middle Pleistocene hominin cranium from Gruta da Aroeira (Portugal)

    PubMed Central

    Daura, Joan; Sanz, Montserrat; Arsuaga, Juan Luis; Hoffmann, Dirk L.; Quam, Rolf M.; Ortega, María Cruz; Santos, Elena; Gómez, Sandra; Rubio, Angel; Villaescusa, Lucía; Souto, Pedro; Mauricio, João; Rodrigues, Filipa; Ferreira, Artur; Godinho, Paulo; Trinkaus, Erik

    2017-01-01

    The Middle Pleistocene is a crucial time period for studying human evolution in Europe, because it marks the appearance of both fossil hominins ancestral to the later Neandertals and the Acheulean technology. Nevertheless, European sites containing well-dated human remains associated with an Acheulean toolkit remain scarce. The earliest European hominin crania associated with Acheulean handaxes are at the sites of Arago, Atapuerca Sima de los Huesos (SH), and Swanscombe, dating to 400–500 ka (Marine Isotope Stage 11–12). The Atapuerca (SH) fossils and the Swanscombe cranium belong to the Neandertal clade, whereas the Arago hominins have been attributed to an incipient stage of Neandertal evolution, to Homo heidelbergensis, or to a subspecies of Homo erectus. A recently discovered cranium (Aroeira 3) from the Gruta da Aroeira (Almonda karst system, Portugal) dating to 390–436 ka provides important evidence on the earliest European Acheulean-bearing hominins. This cranium is represented by most of the right half of a calvarium (with the exception of the missing occipital bone) and a fragmentary right maxilla preserving part of the nasal floor and two fragmentary molars. The combination of traits in the Aroeira 3 cranium augments the previously documented diversity in the European Middle Pleistocene fossil record. PMID:28289213

  16. New Middle Pleistocene hominin cranium from Gruta da Aroeira (Portugal).

    PubMed

    Daura, Joan; Sanz, Montserrat; Arsuaga, Juan Luis; Hoffmann, Dirk L; Quam, Rolf M; Ortega, María Cruz; Santos, Elena; Gómez, Sandra; Rubio, Angel; Villaescusa, Lucía; Souto, Pedro; Mauricio, João; Rodrigues, Filipa; Ferreira, Artur; Godinho, Paulo; Trinkaus, Erik; Zilhão, João

    2017-03-28

    The Middle Pleistocene is a crucial time period for studying human evolution in Europe, because it marks the appearance of both fossil hominins ancestral to the later Neandertals and the Acheulean technology. Nevertheless, European sites containing well-dated human remains associated with an Acheulean toolkit remain scarce. The earliest European hominin crania associated with Acheulean handaxes are at the sites of Arago, Atapuerca Sima de los Huesos (SH), and Swanscombe, dating to 400-500 ka (Marine Isotope Stage 11-12). The Atapuerca (SH) fossils and the Swanscombe cranium belong to the Neandertal clade, whereas the Arago hominins have been attributed to an incipient stage of Neandertal evolution, to Homo heidelbergensis, or to a subspecies of Homo erectus A recently discovered cranium (Aroeira 3) from the Gruta da Aroeira (Almonda karst system, Portugal) dating to 390-436 ka provides important evidence on the earliest European Acheulean-bearing hominins. This cranium is represented by most of the right half of a calvarium (with the exception of the missing occipital bone) and a fragmentary right maxilla preserving part of the nasal floor and two fragmentary molars. The combination of traits in the Aroeira 3 cranium augments the previously documented diversity in the European Middle Pleistocene fossil record.

  17. A Spring Forward for Hominin Evolution in East Africa

    PubMed Central

    Cuthbert, Mark O.; Ashley, Gail M.

    2014-01-01

    Groundwater is essential to modern human survival during drought periods. There is also growing geological evidence of springs associated with stone tools and hominin fossils in the East African Rift System (EARS) during a critical period for hominin evolution (from 1.8 Ma). However it is not known how vulnerable these springs may have been to climate variability and whether groundwater availability may have played a part in human evolution. Recent interdisciplinary research at Olduvai Gorge, Tanzania, has documented climate fluctuations attributable to astronomic forcing and the presence of paleosprings directly associated with archaeological sites. Using palaeogeological reconstruction and groundwater modelling of the Olduvai Gorge paleo-catchment, we show how spring discharge was likely linked to East African climate variability of annual to Milankovitch cycle timescales. Under decadal to centennial timescales, spring flow would have been relatively invariant providing good water resource resilience through long droughts. For multi-millennial periods, modelled spring flows lag groundwater recharge by 100 s to 1000 years. The lag creates long buffer periods allowing hominins to adapt to new habitats as potable surface water from rivers or lakes became increasingly scarce. Localised groundwater systems are likely to have been widespread within the EARS providing refugia and intense competition during dry periods, thus being an important factor in natural selection and evolution, as well as a vital resource during hominin dispersal within and out of Africa. PMID:25207544

  18. A spring forward for hominin evolution in East Africa.

    PubMed

    Cuthbert, Mark O; Ashley, Gail M

    2014-01-01

    Groundwater is essential to modern human survival during drought periods. There is also growing geological evidence of springs associated with stone tools and hominin fossils in the East African Rift System (EARS) during a critical period for hominin evolution (from 1.8 Ma). However it is not known how vulnerable these springs may have been to climate variability and whether groundwater availability may have played a part in human evolution. Recent interdisciplinary research at Olduvai Gorge, Tanzania, has documented climate fluctuations attributable to astronomic forcing and the presence of paleosprings directly associated with archaeological sites. Using palaeogeological reconstruction and groundwater modelling of the Olduvai Gorge paleo-catchment, we show how spring discharge was likely linked to East African climate variability of annual to Milankovitch cycle timescales. Under decadal to centennial timescales, spring flow would have been relatively invariant providing good water resource resilience through long droughts. For multi-millennial periods, modelled spring flows lag groundwater recharge by 100 s to 1000 years. The lag creates long buffer periods allowing hominins to adapt to new habitats as potable surface water from rivers or lakes became increasingly scarce. Localised groundwater systems are likely to have been widespread within the EARS providing refugia and intense competition during dry periods, thus being an important factor in natural selection and evolution, as well as a vital resource during hominin dispersal within and out of Africa.

  19. Hominins on Flores, Indonesia, by one million years ago.

    PubMed

    Brumm, Adam; Jensen, Gitte M; van den Bergh, Gert D; Morwood, Michael J; Kurniawan, Iwan; Aziz, Fachroel; Storey, Michael

    2010-04-01

    Previous excavations at Mata Menge and Boa Lesa in the Soa Basin of Flores, Indonesia, recovered stone artefacts in association with fossilized remains of the large-bodied Stegodon florensis florensis. Zircon fission-track ages from these sites indicated that hominins had colonized the island by 0.88 +/- 0.07 million years (Myr) ago. Here we describe the contents, context and age of Wolo Sege, a recently discovered archaeological site in the Soa Basin that has in situ stone artefacts and that lies stratigraphically below Mata Menge and immediately above the basement breccias of the basin. We show using (40)Ar/(39)Ar dating that an ignimbrite overlying the artefact layers at Wolo Sege was erupted 1.02 +/- 0.02 Myr ago, providing a new minimum age for hominins on Flores. This predates the disappearance from the Soa Basin of 'pygmy' Stegodon sondaari and Geochelone spp. (giant tortoise), as evident at the nearby site of Tangi Talo, which has been dated to 0.90 +/- 0.07 Myr ago. It now seems that this extirpation or possible extinction event and the associated faunal turnover were the result of natural processes rather than the arrival of hominins. It also appears that the volcanic and fluvio-lacustrine deposits infilling the Soa Basin may not be old enough to register the initial arrival of hominins on the island.

  20. Astronomically forced climate change in the Kenyan Rift Valley 2.7-2.55 Ma: implications for the evolution of early hominin ecosystems.

    PubMed

    Kingston, John D; Deino, Alan L; Edgar, Robert K; Hill, Andrew

    2007-11-01

    Global climate change, linked to astronomical forcing factors, has been implicated in faunal evolutionary change in equatorial Africa, including the origin and diversification of hominin lineages. Empirical terrestrial data demonstrating that orbital forcing has a significant effect, or is detectable, at early hominin sites in equatorial continental interiors during the Pliocene, however, remain limited. Sedimentation patterns in the Baringo Basin within the Central Kenyan Rift Valley between ca. 2.7 and 2.55 Ma, controlled by climatic factors, provide a detailed paleoenvironmental record spanning 35 fossil vertebrate localities, including three hominin sites. The succession includes a sequence of diatomites that record rhythmic cycling of major freshwater lake systems consistent with approximately 23-kyr Milankovitch precessional periodicity. The temporal framework of shifting precipitation patterns, relative to Pliocene insolation curves, implicate African monsoonal climatic control and indicate that climatic fluctuations in Rift Valley ecosystems were paced by global climatic change documented in marine cores. These data provide direct evidence of orbitally mediated environmental change at Pliocene Rift Valley hominin fossil localities, providing a unique opportunity to assess the evolutionary effect of short-term climatic flux on late Pliocene East African terrestrial communities.

  1. A revision of hominin fossil teeth from Fontana Ranuccio (Middle Pleistocene, Anagni, Frosinone, Italy).

    PubMed

    Rubini, Mauro; Cerroni, Vittorio; Festa, Giulia; Sardella, Raffaele; Zaio, Paola

    2014-12-01

    The Fontana Ranuccio hominin teeth (FR, Latium, Italy) are dated to the Middle Pleistocene. In previous studies these teeth were classified as two lower (left and right) second molars, one lower left central incisor and a badly worn incisor crown, the exact position of which could not be determined. In 2012 these remains were acquired by the Anthropological Service of S.B.A.L. (Italian Ministry of Culture) and for this reason re-analysed. In a thorough revision we have reassessed them both morphologically and dimensionally as two lower (left and right) first molars, one lower left lateral incisor and a possible upper left canine. The comparison with penecontemporaneous and diachronic samples shows that the Fontana Ranuccio teeth are morphologically similar to Atapuerca-Sima de los Huesos, Arago XIII and Neanderthal samples. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Oldowan hominin behavior and ecology at Kanjera South,Kenya.

    PubMed

    Plummer, Thomas; Bishop, Laura

    2016-06-20

    The Early Stone Age archaeological record does not become persistent and widespread until approximately 2.0-1.7 million years ago, when Oldowan sites spread across Africa and ultimately into Eurasia. However, good records of hominin behavior from this important time interval are uncommon. Here we describe recent findings from the two million year old Oldowan site of Kanjera South, on the Homa Peninsula of southwestern Kenya. Kanjera South is the oldest Oldowan site with large assemblages of stone artifacts and well-preserved archaeological fauna. Our research indicates that hominin activities were situated in an open habitat within a grassland dominated ecosystem, the first documentation of an archaeological site in such an open setting. Hominins selectively collected and transported stone materials (30% of the lithic assemblage) over longer distances (at least 10 km) than is typical for the Oldowan, reflecting their preference for hard, easily-flaked lithologies unavailable on the northern half of the Homa Peninsula. They deployed different technological strategies to more intensively utilize these hard, non-local raw materials. Artifacts were used for a variety of tasks, including butchering small antelopes probably obtained by hunting, working wood, working soft plant material, and processing underground storage organs. These data suggest that the Kanjera hominins utilized a technological system that allowed them to extract nutrient dense animal and plant foods from their environment. This shift towards the acquisition of nutritious, hard-to-acquire foods in packets large enough to be shared may have facilitated brain and body size expansion in the genus Homo.

  3. Hominin footprints from early Pleistocene deposits at Happisburgh, UK.

    PubMed

    Ashton, Nick; Lewis, Simon G; De Groote, Isabelle; Duffy, Sarah M; Bates, Martin; Bates, Richard; Hoare, Peter; Lewis, Mark; Parfitt, Simon A; Peglar, Sylvia; Williams, Craig; Stringer, Chris

    2014-01-01

    Investigations at Happisburgh, UK, have revealed the oldest known hominin footprint surface outside Africa at between ca. 1 million and 0.78 million years ago. The site has long been recognised for the preservation of sediments containing Early Pleistocene fauna and flora, but since 2005 has also yielded humanly made flint artefacts, extending the record of human occupation of northern Europe by at least 350,000 years. The sediments consist of sands, gravels and laminated silts laid down by a large river within the upper reaches of its estuary. In May 2013 extensive areas of the laminated sediments were exposed on the foreshore. On the surface of one of the laminated silt horizons a series of hollows was revealed in an area of ca. 12 m(2). The surface was recorded using multi-image photogrammetry which showed that the hollows are distinctly elongated and the majority fall within the range of juvenile to adult hominin foot sizes. In many cases the arch and front/back of the foot can be identified and in one case the impression of toes can be seen. Using foot length to stature ratios, the hominins are estimated to have been between ca. 0.93 and 1.73 m in height, suggestive of a group of mixed ages. The orientation of the prints indicates movement in a southerly direction on mud-flats along the river edge. Early Pleistocene human fossils are extremely rare in Europe, with no evidence from the UK. The only known species in western Europe of a similar age is Homo antecessor, whose fossil remains have been found at Atapuerca, Spain. The foot sizes and estimated stature of the hominins from Happisburgh fall within the range derived from the fossil evidence of Homo antecessor.

  4. Hominin Footprints from Early Pleistocene Deposits at Happisburgh, UK

    PubMed Central

    Ashton, Nick; Lewis, Simon G.; De Groote, Isabelle; Duffy, Sarah M.; Bates, Martin; Bates, Richard; Hoare, Peter; Lewis, Mark; Parfitt, Simon A.; Peglar, Sylvia; Williams, Craig; Stringer, Chris

    2014-01-01

    Investigations at Happisburgh, UK, have revealed the oldest known hominin footprint surface outside Africa at between ca. 1 million and 0.78 million years ago. The site has long been recognised for the preservation of sediments containing Early Pleistocene fauna and flora, but since 2005 has also yielded humanly made flint artefacts, extending the record of human occupation of northern Europe by at least 350,000 years. The sediments consist of sands, gravels and laminated silts laid down by a large river within the upper reaches of its estuary. In May 2013 extensive areas of the laminated sediments were exposed on the foreshore. On the surface of one of the laminated silt horizons a series of hollows was revealed in an area of ca. 12 m2. The surface was recorded using multi-image photogrammetry which showed that the hollows are distinctly elongated and the majority fall within the range of juvenile to adult hominin foot sizes. In many cases the arch and front/back of the foot can be identified and in one case the impression of toes can be seen. Using foot length to stature ratios, the hominins are estimated to have been between ca. 0.93 and 1.73 m in height, suggestive of a group of mixed ages. The orientation of the prints indicates movement in a southerly direction on mud-flats along the river edge. Early Pleistocene human fossils are extremely rare in Europe, with no evidence from the UK. The only known species in western Europe of a similar age is Homo antecessor, whose fossil remains have been found at Atapuerca, Spain. The foot sizes and estimated stature of the hominins from Happisburgh fall within the range derived from the fossil evidence of Homo antecessor. PMID:24516637

  5. Carnivoran remains from the Malapa hominin site, South Africa.

    PubMed

    Kuhn, Brian F; Werdelin, Lars; Hartstone-Rose, Adam; Lacruz, Rodrigo S; Berger, Lee R

    2011-01-01

    Recent discoveries at the new hominin-bearing deposits of Malapa, South Africa, have yielded a rich faunal assemblage associated with the newly described hominin taxon Australopithecus sediba. Dating of this deposit using U-Pb and palaeomagnetic methods has provided an age of 1.977 Ma, being one of the most accurately dated, time constrained deposits in the Plio-Pleistocene of southern Africa. To date, 81 carnivoran specimens have been identified at this site including members of the families Canidae, Viverridae, Herpestidae, Hyaenidae and Felidae. Of note is the presence of the extinct taxon Dinofelis cf. D. barlowi that may represent the last appearance date for this species. Extant large carnivores are represented by specimens of leopard (Panthera pardus) and brown hyaena (Parahyaena brunnea). Smaller carnivores are also represented, and include the genera Atilax and Genetta, as well as Vulpes cf. V. chama. Malapa may also represent the first appearance date for Felis nigripes (Black-footed cat). The geochronological age of Malapa and the associated hominin taxa and carnivoran remains provide a window of research into mammalian evolution during a relatively unknown period in South Africa and elsewhere. In particular, the fauna represented at Malapa has the potential to elucidate aspects of the evolution of Dinofelis and may help resolve competing hypotheses about faunal exchange between East and Southern Africa during the late Pliocene or early Pleistocene.

  6. Mechanical Constraints on the Hominin Pelvis and the "Obstetrical Dilemma".

    PubMed

    Ruff, Christopher

    2017-05-01

    The "obstetrical dilemma" posits that increases in birth canal dimensions during hominin evolution were constrained by mechanical factors associated with bipedal gait. This model has recently been challenged, in part on the basis of experimental data showing little association between pelvic and proximal femoral dimensions and locomotor costs among human experimental subjects. However, complete rejection of the model is premature, for two reasons: (1) it is difficult to extrapolate experimental results to naturalistic conditions and the much more varied body form and possibly locomotor style of early hominins. Relative pelvic breadth and femoral neck length in both australopiths and early Homo are at or beyond the limits observed among modern humans, and there is evidence that australopiths may have used an altered form of bipedal gait. (2) Other mechanical factors in addition to locomotor cost are important when assessing pelvic and proximal femoral morphology. Increasing biacetabular breadth increases the joint reaction force (JRF) on the femoral head. Increasing femoral neck length may reduce hip JRF, but also increases stress and fracture risk in the femoral neck. Increasing both biacetabular breadth and femoral neck length also increases mediolateral bending stress in the proximal femoral shaft, necessitating substantial buttressing of the diaphysis. Thus, there are mechanical consequences beyond simply locomotor costs that must be considered when evaluating variation in pelvic and femoral morphology among past and extant hominins. Anat Rec, 300:946-955, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  7. Brain ontogeny and life history in Pleistocene hominins

    PubMed Central

    Hublin, Jean-Jacques; Neubauer, Simon; Gunz, Philipp

    2015-01-01

    A high level of encephalization is critical to the human adaptive niche and emerged among hominins over the course of the past 2 Myr. Evolving larger brains required important adaptive adjustments, in particular regarding energy allocation and life history. These adaptations included a relatively small brain at birth and a protracted growth of highly dependent offspring within a complex social environment. In turn, the extended period of growth and delayed maturation of the brain structures of humans contribute to their cognitive complexity. The current palaeoanthropological evidence shows that, regarding life history and brain ontogeny, the Pleistocene hominin taxa display different patterns and that one cannot simply contrast an ‘ape-model’ to a ‘human-model’. Large-brained hominins such as Upper Pleistocene Neandertals have evolved along their own evolutionary pathway and can be distinguished from modern humans in terms of growth pattern and brain development. The life-history pattern and brain ontogeny of extant humans emerged only recently in the course of human evolution. PMID:25602066

  8. Analysis of Human Accelerated DNA Regions Using Archaic Hominin Genomes

    PubMed Central

    Burbano, Hernán A.; Green, Richard E.; Maricic, Tomislav; Lalueza-Fox, Carles; de la Rasilla, Marco; Rosas, Antonio; Kelso, Janet; Pollard, Katherine S.; Lachmann, Michael; Pääbo, Svante

    2012-01-01

    Several previous comparisons of the human genome with other primate and vertebrate genomes identified genomic regions that are highly conserved in vertebrate evolution but fast-evolving on the human lineage. These human accelerated regions (HARs) may be regions of past adaptive evolution in humans. Alternatively, they may be the result of non-adaptive processes, such as biased gene conversion. We captured and sequenced DNA from a collection of previously published HARs using DNA from an Iberian Neandertal. Combining these new data with shotgun sequence from the Neandertal and Denisova draft genomes, we determine at least one archaic hominin allele for 84% of all positions within HARs. We find that 8% of HAR substitutions are not observed in the archaic hominins and are thus recent in the sense that the derived allele had not come to fixation in the common ancestor of modern humans and archaic hominins. Further, we find that recent substitutions in HARs tend to have come to fixation faster than substitutions elsewhere in the genome and that substitutions in HARs tend to cluster in time, consistent with an episodic rather than a clock-like process underlying HAR evolution. Our catalog of sequence changes in HARs will help prioritize them for functional studies of genomic elements potentially responsible for modern human adaptations. PMID:22412940

  9. Homo naledi and Pleistocene hominin evolution in subequatorial Africa

    PubMed Central

    Berger, Lee R; Hawks, John; Dirks, Paul HGM; Elliott, Marina; Roberts, Eric M

    2017-01-01

    New discoveries and dating of fossil remains from the Rising Star cave system, Cradle of Humankind, South Africa, have strong implications for our understanding of Pleistocene human evolution in Africa. Direct dating of Homo naledi fossils from the Dinaledi Chamber (Berger et al., 2015) shows that they were deposited between about 236 ka and 335 ka (Dirks et al., 2017), placing H. naledi in the later Middle Pleistocene. Hawks and colleagues (Hawks et al., 2017) report the discovery of a second chamber within the Rising Star system (Dirks et al., 2015) that contains H. naledi remains. Previously, only large-brained modern humans or their close relatives had been demonstrated to exist at this late time in Africa, but the fossil evidence for any hominins in subequatorial Africa was very sparse. It is now evident that a diversity of hominin lineages existed in this region, with some divergent lineages contributing DNA to living humans and at least H. naledi representing a survivor from the earliest stages of diversification within Homo. The existence of a diverse array of hominins in subequatorial comports with our present knowledge of diversity across other savanna-adapted species, as well as with palaeoclimate and paleoenvironmental data. H. naledi casts the fossil and archaeological records into a new light, as we cannot exclude that this lineage was responsible for the production of Acheulean or Middle Stone Age tool industries. DOI: http://dx.doi.org/10.7554/eLife.24234.001 PMID:28483041

  10. Exploring third metacarpal capitate facet shape in early hominins.

    PubMed

    Rein, Thomas R; Harvati, Katerina

    2013-02-01

    The joint between the capitate and third metacarpal plays an important role in stabilizing the manus during hand use in great apes and humans. Researchers have examined the morphology of this region in humans, our fossil relatives, and other extant primates to try to understand the importance of this joint in human evolution. The first goal of our research was to explore shape variation of the third metacarpal capitate facet across extant anthropoids, including hominoids, cercopithecoids, and platyrrhines. This analysis allowed us to examine the range of variation in the capitate facet and the degree to which locomotor behavior, phylogeny, and size explained shape variation. We also examined capitate facet shape in the early hominin fossil record in order to explore how the shape of this articular surface has changed during early hominin evolution. We captured six landmark coordinates on the edge of the capitate facet in extant anthropoids and fossil specimens to quantify and visualize shape variation in this region. We used principal components analysis, Procrustes distances, and multivariate regression analysis to investigate different possible influences on shape variation. We found that shape variation corresponded to function, phylogeny, and size. With the exception of brachiation, shape variation did not clearly correspond with any specific locomotor behavior. However, we identified a shift in the relative mediolateral breadth of the capitate facet during early hominin evolution, which is most likely one of several adaptations for a more stable joint surface. Copyright © 2012 Wiley Periodicals, Inc.

  11. Homo naledi and Pleistocene hominin evolution in subequatorial Africa.

    PubMed

    Berger, Lee R; Hawks, John; Dirks, Paul Hgm; Elliott, Marina; Roberts, Eric M

    2017-05-09

    New discoveries and dating of fossil remains from the Rising Star cave system, Cradle of Humankind, South Africa, have strong implications for our understanding of Pleistocene human evolution in Africa. Direct dating of Homo naledi fossils from the Dinaledi Chamber (Berger et al., 2015) shows that they were deposited between about 236 ka and 335 ka (Dirks et al., 2017), placing H. naledi in the later Middle Pleistocene. Hawks and colleagues (Hawks et al., 2017) report the discovery of a second chamber within the Rising Star system (Dirks et al., 2015) that contains H. naledi remains. Previously, only large-brained modern humans or their close relatives had been demonstrated to exist at this late time in Africa, but the fossil evidence for any hominins in subequatorial Africa was very sparse. It is now evident that a diversity of hominin lineages existed in this region, with some divergent lineages contributing DNA to living humans and at least H. naledi representing a survivor from the earliest stages of diversification within Homo. The existence of a diverse array of hominins in subequatorial comports with our present knowledge of diversity across other savanna-adapted species, as well as with palaeoclimate and paleoenvironmental data. H. naledi casts the fossil and archaeological records into a new light, as we cannot exclude that this lineage was responsible for the production of Acheulean or Middle Stone Age tool industries.

  12. Carnivoran Remains from the Malapa Hominin Site, South Africa

    PubMed Central

    Kuhn, Brian F.; Werdelin, Lars; Hartstone-Rose, Adam; Lacruz, Rodrigo S.; Berger, Lee R.

    2011-01-01

    Recent discoveries at the new hominin-bearing deposits of Malapa, South Africa, have yielded a rich faunal assemblage associated with the newly described hominin taxon Australopithecus sediba. Dating of this deposit using U-Pb and palaeomagnetic methods has provided an age of 1.977 Ma, being one of the most accurately dated, time constrained deposits in the Plio-Pleistocene of southern Africa. To date, 81 carnivoran specimens have been identified at this site including members of the families Canidae, Viverridae, Herpestidae, Hyaenidae and Felidae. Of note is the presence of the extinct taxon Dinofelis cf. D. barlowi that may represent the last appearance date for this species. Extant large carnivores are represented by specimens of leopard (Panthera pardus) and brown hyaena (Parahyaena brunnea). Smaller carnivores are also represented, and include the genera Atilax and Genetta, as well as Vulpes cf. V. chama. Malapa may also represent the first appearance date for Felis nigripes (Black-footed cat). The geochronological age of Malapa and the associated hominin taxa and carnivoran remains provide a window of research into mammalian evolution during a relatively unknown period in South Africa and elsewhere. In particular, the fauna represented at Malapa has the potential to elucidate aspects of the evolution of Dinofelis and may help resolve competing hypotheses about faunal exchange between East and Southern Africa during the late Pliocene or early Pleistocene. PMID:22073222

  13. Brain ontogeny and life history in Pleistocene hominins.

    PubMed

    Hublin, Jean-Jacques; Neubauer, Simon; Gunz, Philipp

    2015-03-05

    A high level of encephalization is critical to the human adaptive niche and emerged among hominins over the course of the past 2 Myr. Evolving larger brains required important adaptive adjustments, in particular regarding energy allocation and life history. These adaptations included a relatively small brain at birth and a protracted growth of highly dependent offspring within a complex social environment. In turn, the extended period of growth and delayed maturation of the brain structures of humans contribute to their cognitive complexity. The current palaeoanthropological evidence shows that, regarding life history and brain ontogeny, the Pleistocene hominin taxa display different patterns and that one cannot simply contrast an 'ape-model' to a 'human-model'. Large-brained hominins such as Upper Pleistocene Neandertals have evolved along their own evolutionary pathway and can be distinguished from modern humans in terms of growth pattern and brain development. The life-history pattern and brain ontogeny of extant humans emerged only recently in the course of human evolution. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  14. Fission-fusion and the evolution of hominin social systems.

    PubMed

    Grove, Matt; Pearce, Eiluned; Dunbar, R I M

    2012-02-01

    The course of hominin evolution has involved successive migrations towards higher absolute latitudes over the past three million years. Poorer habitat quality further from the equator has led to the necessity for groups occupying higher latitudes to live at lower population densities. Coupled with a trend towards increasing group size over this time period, this tendency towards expansion has led to exponential increases in the area requirements of hominin groups, and a concomitant need to adjust foraging patterns. The current analyses suggest that the development of increasingly complex, multi-level fission-fusion social systems could have freed hominins of the foraging constraints imposed by large group sizes and low population densities. Analyses of the fossil record suggest latitudinally-driven differences in area requirements of the australopithecines from East and South Africa, and African and Asian Homo erectus. In contrast, chronologically-driven differences appear between H. erectus as a whole and Homo heidelbergensis, and between H. heidelbergensis and the Neanderthals. These results are discussed in relation to studies of the foraging patterns of primates and hunter-gatherers. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Ichnotaxonomy of the Laetoli trackways: The earliest hominin footprints

    NASA Astrophysics Data System (ADS)

    Meldrum, D. J.; Lockley, Martin G.; Lucas, Spencer G.; Musiba, Charles

    2011-04-01

    At 3.6 Ma, the Laetoli Pliocene hominin trackways are the earliest direct evidence of hominin bipedalism. Three decades since their discovery, not only is the question of their attribution still discussed, but marked differences in interpretation concerning the footprints' qualitative features and the inferred nature of the early hominin foot morphology remain. Here, we establish a novel ichnotaxon, Praehominipes laetoliensis, for these tracks and clarify the distinctions of these footprints from those of later hominins, especially modern humans. We also contrast hominin, human, and ape footprints to establish morphological features of these footprints correlated with a midtarsal break versus a stiff longitudinal arch. Original photos, including stereo photographs, and casts of footprints from the 1978 Laetoli excavation, confirm midtarsal flexibility, and repeatedly indicate an associated midfoot pressure ridge. In contrast, the modern human footprint reflects the derived arched-foot architecture, combined with a stiff-legged striding gait. Fossilized footprints of unshod modern human pedestrians in Hawaii and Nicaragua unambiguously illustrate these contrasts. Some points of comparisons with ape footprints are complicated by a variable hallucal position and the distinct manner of ape facultative bipedalism. In contrast to the comparatively rigid platform of the modern human foot, midtarsal flexibility is present in the chimpanzee foot. In ape locomotion, flexion at the transverse tarsal joint, referred to as the "midtarsal break," uncouples the respective functions of the prehensile forefoot and the propulsive hindfoot during grasp-climbing. At some point after the transition to habitual bipedalism, these grasp-climb adaptations, presumed to be present in the last common ancestor of apes and humans, were initially compromised by the loss of divergence of the hallux. An analogous trajectory is evident along an array of increasingly terrestrial extant ape species

  16. The late Middle Pleistocene hominin fossil record of eastern Asia: synthesis and review.

    PubMed

    Bae, Christopher J

    2010-01-01

    Traditionally, Middle Pleistocene hominin fossils that cannot be allocated to Homo erectus sensu lato or modern H. sapiens have been assigned to different specific taxa. For example, in eastern Asia, these hominin fossils have been classified as archaic, early, or premodern H. sapiens. An increasing number of Middle Pleistocene hominin fossils are currently being assigned to H. heidelbergensis. This is particularly the case for the African and European Middle Pleistocene hominin fossil record. There have been suggestions that perhaps the eastern Asian late Middle Pleistocene hominins can also be allocated to the H. heidelbergensis hypodigm. In this article, I review the current state of the late Middle Pleistocene hominin fossil record from eastern Asia and examine the various arguments for assigning these hominins to the different specific taxa. The two primary conclusions drawn from this review are as follows: 1) little evidence currently exists in the eastern Asian Middle Pleistocene hominin fossil record to support their assignment to H. heidelbergensis; and 2) rather than add to the growing list of hominin fossil taxa by using taxonomic names like H. daliensis for northeast Asian fossils and H. mabaensis for Southeast Asian fossils, it is better to err on the side of caution and continue to use the term archaic H. sapiens to represent all of these hominin fossils. What should be evident from this review is the need for an increase in the quality and quantity of the eastern Asian hominin fossil data set. Fortunately, with the increasing number of large-scale multidisciplinary paleoanthropological field and laboratory research projects in eastern Asia, the record is quickly becoming better understood. Copyright © 2010 Wiley-Liss, Inc.

  17. Functional morphology of the ankle and the likelihood of climbing in early hominins

    PubMed Central

    DeSilva, Jeremy M.

    2009-01-01

    Whether early hominins were adept tree climbers is unclear. Although some researchers have argued that bipedality maladapts the hominin skeleton for climbing, others have argued that early hominin fossils display an amalgamation of features consistent with both locomotor strategies. Although chimpanzees have featured prominently in these arguments, there are no published data on the kinematics of climbing in wild chimpanzees. Without these biomechanical data describing how chimpanzees actually climb trees, identifying correlates of climbing in modern ape skeletons is difficult, thereby limiting accurate interpretations of the hominin fossil record. Here, the first kinematic data on vertical climbing in wild chimpanzees are presented. These data are used to identify skeletal correlates of climbing in the ankle joint of the African apes to more accurately interpret hominin distal tibiae and tali. This study finds that chimpanzees engage in an extraordinary range of foot dorsiflexion and inversion during vertical climbing bouts. Two skeletal correlates of modern ape-like vertical climbing are identified in the ankle joint and related to positions of dorsiflexion and foot inversion. A study of the 14 distal tibiae and 15 tali identified and published as hominins from 4.12 to 1.53 million years ago finds that the ankles of early hominins were poorly adapted for modern ape-like vertical climbing bouts. This study concludes that if hominins included tree climbing as part of their locomotor repertoire, then they were performing this activity in a manner decidedly unlike modern chimpanzees. PMID:19365068

  18. The hominoid proximal radius: re-interpreting locomotor behaviors in early hominins.

    PubMed

    Patel, Biren A

    2005-04-01

    Studies of fossil hominins are traditionally taxonomically narrow and often exclude comparisons with hylobatids. Hence, results of functional analyses of postcrania, interpreted as indicating that early hominins are "African-ape-like" in their postcranial skeletons and positional behaviors, may reflect an artifact of inadequate taxonomic and morphological breadth of the comparative sample. To address this problem and better understand early hominin positional behaviors, this study included hylobatids in a comparative analysis, focusing on the hominoid elbow joint. Specifically, morphometric variables of the proximal radius were derived from measurements from a sample of all genera of extant hominoids and casts of extinct hominin species. Univariate and multivariate analyses were performed on these data. Results show that early hominins are morphologically diverse and are not, as a group, similar to any one extant group. Instead, the fossils resemble Pan, Gorilla, and Hylobates, and are not like modern Homo sapiens or Pongo. This suggests that the morphology of Hylobates may reflect a morphotype for all later hominoids, thus complicating the functional interpretations of fossil hominins. The implications of these results are that the proximal radius is not a sensitive indicator of locomotor behavior among hominoids since the morphology in hylobatids and Gorilla and Pan is similar despite widely varying positional repertoires. Furthermore, inferences of function from form in extinct hominins can be drastically affected by the comparative outgroup selection. A re-evaluation of the functional morphology of the proximal radius in early hominins is addressed.

  19. Bayesian analysis of a morphological supermatrix sheds light on controversial fossil hominin relationships

    PubMed Central

    Dembo, Mana; Matzke, Nicholas J.; Mooers, Arne Ø.; Collard, Mark

    2015-01-01

    The phylogenetic relationships of several hominin species remain controversial. Two methodological issues contribute to the uncertainty—use of partial, inconsistent datasets and reliance on phylogenetic methods that are ill-suited to testing competing hypotheses. Here, we report a study designed to overcome these issues. We first compiled a supermatrix of craniodental characters for all widely accepted hominin species. We then took advantage of recently developed Bayesian methods for building trees of serially sampled tips to test among hypotheses that have been put forward in three of the most important current debates in hominin phylogenetics—the relationship between Australopithecus sediba and Homo, the taxonomic status of the Dmanisi hominins, and the place of the so-called hobbit fossils from Flores, Indonesia, in the hominin tree. Based on our results, several published hypotheses can be statistically rejected. For example, the data do not support the claim that Dmanisi hominins and all other early Homo specimens represent a single species, nor that the hobbit fossils are the remains of small-bodied modern humans, one of whom had Down syndrome. More broadly, our study provides a new baseline dataset for future work on hominin phylogeny and illustrates the promise of Bayesian approaches for understanding hominin phylogenetic relationships. PMID:26202999

  20. Subocclusal dental morphology of sahelanthropus tchadensis and the evolution of teeth in hominins.

    PubMed

    Emonet, Edouard-Georges; Andossa, Likius; Taïsso Mackaye, Hassane; Brunet, Michel

    2014-01-01

    The evolution of the teeth in hominins is characterized by, among other characters, major changes in root morphology. However, little is known of the evolution from a plesiomorphic, ape-like root morphology to the crown hominin morphology. Here we present a study of the root morphology of the Miocene Chadian hominin Sahelanthropus tchadensis and its comparison to other hominins. The morphology of the whole lower dentition (I1 -M3 ) was investigated and described. The comparison with the species Ardipithecus kaddaba and Ardipithecus ramidus indicates a global homogeneity of root morphology in early hominins. This morphology, characterized notably by a reduction of the size and number of the roots of premolars, is a composite between an ape-like morphology and the later hominin morphology. Trends for root evolution in hominins are proposed, including the transition from a basal hominoid to extant Homo sapiens. This study also illustrates the low association between the evolution of tooth root morphology and the evolution of crowns in hominins.

  1. Bayesian analysis of a morphological supermatrix sheds light on controversial fossil hominin relationships.

    PubMed

    Dembo, Mana; Matzke, Nicholas J; Mooers, Arne Ø; Collard, Mark

    2015-08-07

    The phylogenetic relationships of several hominin species remain controversial. Two methodological issues contribute to the uncertainty-use of partial, inconsistent datasets and reliance on phylogenetic methods that are ill-suited to testing competing hypotheses. Here, we report a study designed to overcome these issues. We first compiled a supermatrix of craniodental characters for all widely accepted hominin species. We then took advantage of recently developed Bayesian methods for building trees of serially sampled tips to test among hypotheses that have been put forward in three of the most important current debates in hominin phylogenetics--the relationship between Australopithecus sediba and Homo, the taxonomic status of the Dmanisi hominins, and the place of the so-called hobbit fossils from Flores, Indonesia, in the hominin tree. Based on our results, several published hypotheses can be statistically rejected. For example, the data do not support the claim that Dmanisi hominins and all other early Homo specimens represent a single species, nor that the hobbit fossils are the remains of small-bodied modern humans, one of whom had Down syndrome. More broadly, our study provides a new baseline dataset for future work on hominin phylogeny and illustrates the promise of Bayesian approaches for understanding hominin phylogenetic relationships.

  2. The Pliocene hominin diversity conundrum: Do more fossils mean less clarity?

    PubMed Central

    Haile-Selassie, Yohannes; Melillo, Stephanie M.; Su, Denise F.

    2016-01-01

    Recent discoveries of multiple middle Pliocene hominins have raised the possibility that early hominins were as speciose as later hominins. However, debates continue to arise around the validity of most of these new taxa, largely based on poor preservation of holotype specimens, small sample size, or the lack of evidence for ecological diversity. A closer look at the currently available fossil evidence from Ethiopia, Kenya, and Chad indicate that Australopithecus afarensis was not the only hominin species during the middle Pliocene, and that there were other species clearly distinguishable from it by their locomotor adaptation and diet. Although there is no doubt that the presence of multiple species during the middle Pliocene opens new windows into our evolutionary past, it also complicates our understanding of early hominin taxonomy and phylogenetic relationships. PMID:27274043

  3. Late Miocene hominin teeth from the Gona Paleoanthropological Research Project area, Afar, Ethiopia.

    PubMed

    Simpson, Scott W; Kleinsasser, Lynnette; Quade, Jay; Levin, Naomi E; McIntosh, William C; Dunbar, Nelia; Semaw, Sileshi; Rogers, Michael J

    2015-04-01

    Since 2000, significant collections of Latest Miocene hominin fossils have been recovered from Chad, Kenya, and Ethiopia. These fossils have provided a better understanding of earliest hominin biology and context. Here, we describe five hominin teeth from two periods (ca. 5.4 Million-years-ago and ca. 6.3 Ma) that were recovered from the Adu-Asa Formation in the Gona Paleoanthropological Research Project area in the Afar, Ethiopia that we assign to either Hominina, gen. et sp. indet. or Ardipithecus kadabba. These specimens are compared with extant African ape and other Latest Miocene and Early Pliocene hominin teeth. The derived morphology of the large, non-sectorial maxillary canine and mandibular third premolar links them with later hominins and they are phenetically distinguishable and thus phyletically distinct from extant apes.

  4. New footprints from Laetoli (Tanzania) provide evidence for marked body size variation in early hominins.

    PubMed

    Masao, Fidelis T; Ichumbaki, Elgidius B; Cherin, Marco; Barili, Angelo; Boschian, Giovanni; Iurino, Dawid A; Menconero, Sofia; Moggi-Cecchi, Jacopo; Manzi, Giorgio

    2016-12-14

    Laetoli is a well-known palaeontological locality in northern Tanzania whose outstanding record includes the earliest hominin footprints in the world (3.66 million years old), discovered in 1978 at Site G and attributed to Australopithecus afarensis. Here, we report hominin tracks unearthed in the new Site S at Laetoli and referred to two bipedal individuals (S1 and S2) moving on the same palaeosurface and in the same direction as the three hominins documented at Site G. The stature estimates for S1 greatly exceed those previously reconstructed for Au. afarensis from both skeletal material and footprint data. In combination with a comparative reappraisal of the Site G footprints, the evidence collected here embodies very important additions to the Pliocene record of hominin behaviour and morphology. Our results are consistent with considerable body size variation and, probably, degree of sexual dimorphism within a single species of bipedal hominins as early as 3.66 million years ago.

  5. An ecological and behavioural approach to hominin evolution during the Pliocene

    NASA Astrophysics Data System (ADS)

    Macho, Gabriele A.

    2014-07-01

    The study considers the turnover in hominins, together with carnivorans and other primates, at 3.5 Ma against an environmental backdrop. Communalities are identified between evolving guilds that may directly inform hominin evolution. These are the evolution of (a) dietary generalists and (b) evidence for sociality in carnivores, baboons and hominins. Sociality and behavioural flexibility are regarded advantageous for the procurement of resources while, at the same time, reducing intraspecific competition; in primates it may initially also have served to reduce predation risk. Behavioural flexibility explains the evolutionary success of Panthera leo, Papio and Homo. Viewed within a wider palaeoecological and environmental context, it is possible that sociality in hominins, including allocare, were triggered by abiotic changes at about 3.5 Ma. If confirmed in future studies, this would mark the beginning of hominin life history evolution.

  6. The Pliocene hominin diversity conundrum: Do more fossils mean less clarity?

    PubMed

    Haile-Selassie, Yohannes; Melillo, Stephanie M; Su, Denise F

    2016-06-07

    Recent discoveries of multiple middle Pliocene hominins have raised the possibility that early hominins were as speciose as later hominins. However, debates continue to arise around the validity of most of these new taxa, largely based on poor preservation of holotype specimens, small sample size, or the lack of evidence for ecological diversity. A closer look at the currently available fossil evidence from Ethiopia, Kenya, and Chad indicate that Australopithecus afarensis was not the only hominin species during the middle Pliocene, and that there were other species clearly distinguishable from it by their locomotor adaptation and diet. Although there is no doubt that the presence of multiple species during the middle Pliocene opens new windows into our evolutionary past, it also complicates our understanding of early hominin taxonomy and phylogenetic relationships.

  7. Connecting local environmental sequences to global climate patterns: evidence from the hominin-bearing Hadar Formation, Ethiopia.

    PubMed

    Campisano, Christopher J; Feibel, Craig S

    2007-11-01

    Central to the debate surrounding global climate change and Plio-Pleistocene hominin evolution is the degree to which orbital-scale climate patterns influence low-latitude continental ecosystems and how these influences can be distinguished from regional volcano-tectonic events and local environmental effects. The Pliocene Hadar Formation of Ethiopia preserves a record of hominin paleoenvironments from roughly 3.5 to 2.2 Ma at a temporal resolution relevant to evolutionary change within hominins and other taxa. This study integrates the high-resolution sedimentological and paleontological records at Hadar with climate proxies such as marine core isotope, dust, and sapropel records. Consistent cycling observed both between and within fluvial and lacustrine depositional environments prior to 2.9 Ma at Hadar appears to be predominantly climatic in nature. In contrast a significant change in depositional facies after 2.9 Ma to sequences dominated by conglomerate cut-and-fill cycles indicates a strong tectonic signature related to regional developments in the Main Ethiopian Rift. While specific events seen in marine proxy records may have parallels in the Hadar environmental archive, their overall patterns of high versus low variability may be even more relevant. For example, periods of relatively high-amplitude climate oscillations between 3.15 and 2.95 Ma may be linked to noted size-related morphological changes within the Hadar Australopithecus afarensis lineage and a significant increase in more arid-adapted bovid taxa. Increased aridity in East Africa during this period is also indicated by peaks in eolian dust in the marine core record. Conversely, the dominant lacustrine phase at Hadar ca. 3.3 Ma coincides with the least variable period in several climate proxy records, including marine core foraminifera delta(18)O values and eolian dust concentration. This phase is also coeval with low insolation variability and a very distinct and significant long-term period

  8. The Middle Pleistocene archaeological record of Greece and the role of the Aegean in hominin dispersals: new data and interpretations

    NASA Astrophysics Data System (ADS)

    Tourloukis, Vangelis; Karkanas, Panagiotis

    2012-06-01

    In the debate about hominin dispersals, Greece is expected to have been among the core areas for the peopling of Eurasia, serving as a 'refugium' and source region for (re)colonizations. Yet, its early Pleistocene record is still scarce, forming a conspicuous 'gap' in the early human geography of the Mediterranean. Here we investigate this gap and provide for the first time a synthesis of the Lower Palaeolithic record of Greece. Our study adopts a geoarchaeological approach to explain the current status of the record and argues that the 'absence of evidence' should be understood as the result of the biasing effects of erosional geomorphic processes and not as an indication of a former absence of hominins. In this line, the potential for archaeological preservation and recovery is assessed as a function of landscape dynamics. Climatic seasonality, tectonic activity, high relief and marine inundations have altogether contributed to significant reworking and/or total loss of archaeological sites: in spatial terms, only about 2-5% of the Lower Palaeolithic record of Greece may have survived up to the present. On the other hand, we interpret recent geological data, which show that half of the Aegean Sea would have been subaerially exposed for most of the early Pleistocene. Our results emphasize the potentially central role of the Aegean region in hominin dispersals, both as a biogeographical landbridge and as a highly productive landscape for occupation. This conclusion opens up new prospects for future fieldwork in an area that was hitherto essentially neglected. Finally, in showing how geomorphic processes bias site distribution patterns, the results and methodological perspective developed here can be seen as having implications that are wider than the geographical limits of the Greek Peninsula: they are pertinent to the investigation and interpretation of the early Pleistocene archaeological records in the highly dynamic landscapes of southern Europe - if not in

  9. Dental Ontogeny in Pliocene and Early Pleistocene Hominins

    PubMed Central

    Smith, Tanya M.; Tafforeau, Paul; Le Cabec, Adeline; Bonnin, Anne; Houssaye, Alexandra; Pouech, Joane; Moggi-Cecchi, Jacopo; Manthi, Fredrick; Ward, Carol; Makaremi, Masrour; Menter, Colin G.

    2015-01-01

    Until recently, our understanding of the evolution of human growth and development derived from studies of fossil juveniles that employed extant populations for both age determination and comparison. This circular approach has led to considerable debate about the human-like and ape-like affinities of fossil hominins. Teeth are invaluable for understanding maturation as age at death can be directly assessed from dental microstructure, and dental development has been shown to correlate with life history across primates broadly. We employ non-destructive synchrotron imaging to characterize incremental development, molar emergence, and age at death in more than 20 Australopithecus anamensis, Australopithecus africanus, Paranthropus robustus and South African early Homo juveniles. Long-period line periodicities range from at least 6–12 days (possibly 5–13 days), and do not support the hypothesis that australopiths have lower mean values than extant or fossil Homo. Crown formation times of australopith and early Homo postcanine teeth fall below or at the low end of extant human values; Paranthropus robustus dentitions have the shortest formation times. Pliocene and early Pleistocene hominins show remarkable variation, and previous reports of age at death that employ a narrow range of estimated long-period line periodicities, cuspal enamel thicknesses, or initiation ages are likely to be in error. New chronological ages for SK 62 and StW 151 are several months younger than previous histological estimates, while Sts 24 is more than one year older. Extant human standards overestimate age at death in hominins predating Homo sapiens, and should not be applied to other fossil taxa. We urge caution when inferring life history as aspects of dental development in Pliocene and early Pleistocene fossils are distinct from modern humans and African apes, and recent work has challenged the predictive power of primate-wide associations between hominoid first molar emergence and

  10. Middle and later Pleistocene hominins in Africa and Southwest Asia

    PubMed Central

    Rightmire, G. Philip

    2009-01-01

    Approximately 700,000 years ago, Homo erectus in Africa was giving way to populations with larger brains accompanied by structural adjustments to the vault, cranial base, and face. Such early Middle Pleistocene hominins were not anatomically modern. Their skulls display strong supraorbital tori above projecting faces, flattened frontals, and less parietal expansion than is the case for Homo sapiens. Postcranial remains seem also to have archaic features. Subsequently, some groups evolved advanced skeletal morphology, and by ca. 200,000 years ago, individuals more similar to recent humans are present in the African record. These fossils are associated with Middle Stone Age lithic assemblages and, in some cases, Acheulean tools. Crania from Herto in Ethiopia carry defleshing cutmarks and superficial scoring that may be indicative of mortuary practices. Despite these signs of behavioral innovation, neither the Herto hominins, nor others from Late Pleistocene sites such as Klasies River in southern Africa and Skhūl/Qafzeh in Israel, can be matched in living populations. Skulls are quite robust, and it is only after ≈35,000 years ago that people with more gracile, fully modern morphology make their appearance. Not surprisingly, many questions concerning this evolutionary history have been raised. Attention has centered on systematics of the mid-Pleistocene hominins, their paleobiology, and the timing of dispersals that spread H. sapiens out of Africa and across the Old World. In this report, I discuss structural changes characterizing the skulls from different time periods, possible regional differences in morphology, and the bearing of this evidence on recognizing distinct species. PMID:19581595

  11. Dental evidence for the diets of Plio-Pleistocene hominins.

    PubMed

    Ungar, Peter S

    2011-01-01

    Diet is fundamental to the interaction between an organism and its environment, and is therefore an important key to understanding ecology and evolution. It should come as no surprise then that paleoanthropologists have put a great deal of effort into reconstructing the diets of Plio-Pleistocene hominins. Most of this effort has focused on teeth; these durable parts of the digestive system are usually the most commonly preserved elements in vertebrate fossil assemblages. In this article, I review much of this work. Tooth size, occlusal morphology, enamel thickness, and microstructure provide evidence for the physical properties of the foods to which a species was adapted. Dental microwear can offer insights into the properties of foods that an individual ate on a day-to-day basis. Taken together, these lines of evidence can offer important insights into early hominin food choices and adaptations. New methods of analysis and theoretical perspectives are improving our understanding of the diets of Australopithecus, Paranthropus, and early Homo, and promise further progress long into the future.

  12. LB1's virtual endocast, microcephaly, and hominin brain evolution.

    PubMed

    Falk, Dean; Hildebolt, Charles; Smith, Kirk; Morwood, M J; Sutikna, Thomas; Jatmiko; Wayhu Saptomo, E; Prior, Fred

    2009-11-01

    Earlier observations of the virtual endocast of LB1, the type specimen for Homo floresiensis, are reviewed, extended, and interpreted. Seven derived features of LB1's cerebral cortex are detailed: a caudally-positioned occipital lobe, lack of a rostrally-located lunate sulcus, a caudally-expanded temporal lobe, advanced morphology of the lateral prefrontal cortex, shape of the rostral prefrontal cortex, enlarged gyri in the frontopolar region, and an expanded orbitofrontal cortex. These features indicate that LB1's brain was globally reorganized despite its ape-sized cranial capacity (417cm(3)). Neurological reorganization may thus form the basis for the cognitive abilities attributed to H. floresiensis. Because of its tiny cranial capacity, some workers think that LB1 represents a Homo sapiens individual that was afflicted with microcephaly, or some other pathology, rather than a new species of hominin. We respond to concerns about our earlier study of microcephalics compared with normal individuals, and reaffirm that LB1 did not suffer from this pathology. The intense controversy about LB1 reflects an older continuing dispute about the relative evolutionary importance of brain size versus neurological reorganization. LB1 may help resolve this debate and illuminate constraints that governed hominin brain evolution.

  13. Reading the landscape: Legible environments and hominin dispersals.

    PubMed

    Guiducci, Dario; Burke, Ariane

    2016-05-06

    Wayfinding, or the ability to plan and navigate a course over the landscape, is a subject of investigation in geography, neurophysiology, psychology, urban planning, and landscape design. With the prevalence of GPS-assisted navigation systems, or "wayfinders," computer scientists are also increasingly interested in understanding how people plan their movements and guide others. However, the importance of wayfinding as a process that regulates human mobility has only recently been incorporated into archeological research design. Hominin groups were able to disperse widely during the course of prehistory. The scope of these dispersals speaks to the innate navigation abilities of hominins. Their long-term success must have depended on an ability to communicate spatial information effectively. Here, we consider the extent to which some landscapes may have been more conducive to wayfinding than others. We also describe a tool we have created for quantifying landscape legibility (sensu Gollege), a complex and under-explored concept in archeology, with a view to investigating the impact of landscape structure on human wayfinding and thus, patterns of dispersal during prehistory. To this end, we have developed a method for quantifying legibility using a Geographic Information System (GIS) and apply it to a test case in prehistoric Iberia. © 2016 Wiley Periodicals, Inc.

  14. Hominin teeth from the early Late Pleistocene site of Xujiayao, Northern China.

    PubMed

    Xing, Song; Martinón-Torres, María; Bermúdez de Castro, Jose María; Wu, Xiujie; Liu, Wu

    2015-02-01

    It is generally accepted that from the late Middle to the early Late Pleistocene (∼340-90 ka BP), Neanderthals were occupying Europe and Western Asia, whereas anatomically modern humans were present in the African continent. In contrast, the paucity of hominin fossil evidence from East Asia from this period impedes a complete evolutionary picture of the genus Homo, as well as assessment of the possible contribution of or interaction with Asian hominins in the evolution of Homo sapiens and Homo neanderthalensis. Here we present a comparative study of a hominin dental sample recovered from the Xujiayao site, in Northern China, attributed to the early Late Pleistocene (MIS 5 to 4). Our dental study reveals a mosaic of primitive and derived dental features for the Xujiayao hominins that can be summarized as follows: i) they are different from archaic and recent modern humans, ii) they present some features that are common but not exclusive to the Neanderthal lineage, and iii) they retain some primitive conformations classically found in East Asian Early and Middle Pleistocene hominins despite their young geological age. Thus, our study evinces the existence in China of a population of unclear taxonomic status with regard to other contemporary populations such as H. sapiens and H. neanderthalensis. The morphological and metric studies of the Xujiayao teeth expand the variability known for early Late Pleistocene hominin fossils and suggest the possibility that a primitive hominin lineage may have survived late into the Late Pleistocene in China. Copyright © 2014 Wiley Periodicals, Inc.

  15. Relationship between dental development and skeletal growth in modern humans and its implications for interpreting ontogeny in fossil hominins.

    PubMed

    Sešelj, Maja

    2013-01-01

    Dental development and skeletal growth are central aspects used by anthropologists when investigating the ontogeny of a population or species. The interrelatedness of the two phenomena is often assumed to be high, but the nature of their relationship is obscured by the fact that they are both highly dependent upon chronological age. The exact relationship between the tempo of dental development and skeletal growth is unclear even in modern humans, which limits the ability to extrapolate to archaeological or fossil forms. It is clear that the influence of chronological age on these two aspects of ontogeny must be accounted for before examining their relationship to one another. This study tests whether dental development and skeletal growth are conditionally independent given age using known-age modern human skeletal samples and proportional odds logistic regression. The results suggest that dental development and skeletal growth are moderately correlated and thus not conditionally independent given age. That is, individuals that are dentally advanced relative to their peers also tend to be skeletally advanced. However, this relationship is moderate at best, so dental development does not appear to be a highly reliable proxy for skeletal growth, or vice versa, in modern humans. These findings have implications for the reconstruction of ontogeny and life history of fossil hominin taxa, since the pace of dental development is often used as a life history proxy. Implications of this study suggest that the proposed accelerated dental development in Pleistocene hominins was not necessarily accompanied by faster skeletal growth. Copyright © 2012 Wiley Periodicals, Inc.

  16. A mitochondrial genome sequence of a hominin from Sima de los Huesos.

    PubMed

    Meyer, Matthias; Fu, Qiaomei; Aximu-Petri, Ayinuer; Glocke, Isabelle; Nickel, Birgit; Arsuaga, Juan-Luis; Martínez, Ignacio; Gracia, Ana; de Castro, José María Bermúdez; Carbonell, Eudald; Pääbo, Svante

    2014-01-16

    Excavations of a complex of caves in the Sierra de Atapuerca in northern Spain have unearthed hominin fossils that range in age from the early Pleistocene to the Holocene. One of these sites, the 'Sima de los Huesos' ('pit of bones'), has yielded the world's largest assemblage of Middle Pleistocene hominin fossils, consisting of at least 28 individuals dated to over 300,000 years ago. The skeletal remains share a number of morphological features with fossils classified as Homo heidelbergensis and also display distinct Neanderthal-derived traits. Here we determine an almost complete mitochondrial genome sequence of a hominin from Sima de los Huesos and show that it is closely related to the lineage leading to mitochondrial genomes of Denisovans, an eastern Eurasian sister group to Neanderthals. Our results pave the way for DNA research on hominins from the Middle Pleistocene.

  17. Surprising trunk rotational capabilities in chimpanzees and implications for bipedal walking proficiency in early hominins.

    PubMed

    Thompson, Nathan E; Demes, Brigitte; O'Neill, Matthew C; Holowka, Nicholas B; Larson, Susan G

    2015-10-06

    Human walking entails coordinated out-of-phase axial rotations of the thorax and pelvis. A long-held assumption is that this ability relies on adaptations for trunk flexibility present in humans, but not in chimpanzees, other great apes, or australopithecines. Here we use three-dimensional kinematic analyses to show that, contrary to current thinking, chimpanzees walking bipedally rotate their lumbar and thoracic regions in a manner similar to humans. This occurs despite differences in the magnitude of trunk motion, and despite morphological differences in truncal 'rigidity' between species. These results suggest that, like humans and chimpanzees, early hominins walked with upper body rotations that countered pelvic rotation. We demonstrate that even if early hominins walked with pelvic rotations 50% larger than humans, they may have accrued the energetic and mechanical benefits of out-of-phase thoracic rotations. This would have allowed early hominins to reduce work and locomotor cost, improving walking efficiency early in hominin evolution.

  18. Woody cover and hominin environments in the past 6million years

    NASA Astrophysics Data System (ADS)

    Cerling, Thure E.; Wynn, Jonathan G.; Andanje, Samuel A.; Bird, Michael I.; Korir, David Kimutai; Levin, Naomi E.; Mace, William; Macharia, Anthony N.; Quade, Jay; Remien, Christopher H.

    2011-08-01

    The role of African savannahs in the evolution of early hominins has been debated for nearly a century. Resolution of this issue has been hindered by difficulty in quantifying the fraction of woody cover in the fossil record. Here we show that the fraction of woody cover in tropical ecosystems can be quantified using stable carbon isotopes in soils. Furthermore, we use fossil soils from hominin sites in the Awash and Omo-Turkana basins in eastern Africa to reconstruct the fraction of woody cover since the Late Miocene epoch (about 7 million years ago). 13C/12C ratio data from 1,300 palaeosols at or adjacent to hominin sites dating to at least 6million years ago show that woody cover was predominantly less than ~40% at most sites. These data point to the prevalence of open environments at the majority of hominin fossil sites in eastern Africa over the past 6million years.

  19. Docosahexaenoic acid and shore-based diets in hominin encephalization: a rebuttal.

    PubMed

    Cunnane, Stephen C; Plourde, Mélanie; Stewart, Kathy; Crawford, Michael A

    2007-01-01

    Carlson and Kingston ([2007]: Am J Hum Biol 19:132-141) propose that preformed dietary docosahexaenoic acid (an omega-3 fatty acid in fish) did not have a significant role in hominin encephalization. Their position hinges on claiming that humans are able to make sufficient docosahexaenoic acid from the plant-based "parent" omega-3 fatty acid-alpha-linolenic acid. They also suggest that hominin fish consumption occurred too late to have materially influenced encephalization. The authors quantify here a summary of the published data showing that humans cannot make sufficient docosahexaenoic acid to maintain normal infant brain development. The authors also provide evidence that the fossil record shows that some of the earliest hominins were regularly consuming fish. Hence, we reject Carlson and Kingston's position and reiterate support for the concept that access to shore-based diets containing docosahexaenoic acid was necessary for hominin encephalization beyond the level seen in the great apes.

  20. Modelling the role of groundwater hydro-refugia in East African hominin evolution and dispersal

    NASA Astrophysics Data System (ADS)

    Cuthbert, M. O.; Gleeson, T.; Reynolds, S. C.; Bennett, M. R.; Newton, A. C.; McCormack, C. J.; Ashley, G. M.

    2017-05-01

    Water is a fundamental resource, yet its spatiotemporal availability in East Africa is poorly understood. This is the area where most hominin first occurrences are located, and consequently the potential role of water in hominin evolution and dispersal remains unresolved. Here, we show that hundreds of springs currently distributed across East Africa could function as persistent groundwater hydro-refugia through orbital-scale climate cycles. Groundwater buffers climate variability according to spatially variable groundwater response times determined by geology and topography. Using an agent-based model, grounded on the present day landscape, we show that groundwater availability would have been critical to supporting isolated networks of hydro-refugia during dry periods when potable surface water was scarce. This may have facilitated unexpected variations in isolation and dispersal of hominin populations in the past. Our results therefore provide a new environmental framework in which to understand how patterns of taxonomic diversity in hominins may have developed.

  1. Modelling the role of groundwater hydro-refugia in East African hominin evolution and dispersal

    PubMed Central

    Cuthbert, M. O.; Gleeson, T.; Reynolds, S. C.; Bennett, M. R.; Newton, A. C.; McCormack, C. J.; Ashley, G. M.

    2017-01-01

    Water is a fundamental resource, yet its spatiotemporal availability in East Africa is poorly understood. This is the area where most hominin first occurrences are located, and consequently the potential role of water in hominin evolution and dispersal remains unresolved. Here, we show that hundreds of springs currently distributed across East Africa could function as persistent groundwater hydro-refugia through orbital-scale climate cycles. Groundwater buffers climate variability according to spatially variable groundwater response times determined by geology and topography. Using an agent-based model, grounded on the present day landscape, we show that groundwater availability would have been critical to supporting isolated networks of hydro-refugia during dry periods when potable surface water was scarce. This may have facilitated unexpected variations in isolation and dispersal of hominin populations in the past. Our results therefore provide a new environmental framework in which to understand how patterns of taxonomic diversity in hominins may have developed. PMID:28556825

  2. Further new hominin fossils from the Kibish Formation, southwestern Ethiopia.

    PubMed

    Pearson, Osbjorn M; Fleagle, John G; Grine, Frederick E; Royer, Danielle F

    2008-09-01

    In addition to the new fragments of the Omo I skeleton, renewed fieldwork in the Kibish Formation along the lower reaches of the Omo River in southwestern Ethiopia has yielded new hominin finds from the Kibish Formation. The new finds include four heavily mineralized specimens: a partial left tibia and a fragment of a distal fibular diaphysis from Awoke's Hominid Site (AHS), a parietal fragment, and a portion of a juvenile occipital bone. The AHS tibia and fibula derive from Member I and are contemporaneous with Omo I and II. The other specimens derive from Chad's Hominid Site (CHS), and derive from either Member III or IV, which constrains their age between approximately 8.6 and approximately 104 ka.

  3. Viewpoints: feeding mechanics, diet, and dietary adaptations in early hominins.

    PubMed

    Daegling, David J; Judex, Stefan; Ozcivici, Engin; Ravosa, Matthew J; Taylor, Andrea B; Grine, Frederick E; Teaford, Mark F; Ungar, Peter S

    2013-07-01

    Inference of feeding adaptation in extinct species is challenging, and reconstructions of the paleobiology of our ancestors have utilized an array of analytical approaches. Comparative anatomy and finite element analysis assist in bracketing the range of capabilities in taxa, while microwear and isotopic analyses give glimpses of individual behavior in the past. These myriad approaches have limitations, but each contributes incrementally toward the recognition of adaptation in the hominin fossil record. Microwear and stable isotope analysis together suggest that australopiths are not united by a single, increasingly specialized dietary adaptation. Their traditional (i.e., morphological) characterization as "nutcrackers" may only apply to a single taxon, Paranthropus robustus. These inferences can be rejected if interpretation of microwear and isotopic data can be shown to be misguided or altogether erroneous. Alternatively, if these sources of inference are valid, it merely indicates that there are phylogenetic and developmental constraints on morphology. Inherently, finite element analysis is limited in its ability to identify adaptation in paleobiological contexts. Its application to the hominin fossil record to date demonstrates only that under similar loading conditions, the form of the stress field in the australopith facial skeleton differs from that in living primates. This observation, by itself, does not reveal feeding adaptation. Ontogenetic studies indicate that functional and evolutionary adaptation need not be conceptually isolated phenomena. Such a perspective helps to inject consideration of mechanobiological principles of bone formation into paleontological inferences. Finite element analysis must employ such principles to become an effective research tool in this context. Copyright © 2013 Wiley Periodicals, Inc.

  4. Bite force and occlusal stress production in hominin evolution.

    PubMed

    Eng, Carolyn M; Lieberman, Daniel E; Zink, Katherine D; Peters, Michael A

    2013-08-01

    Maximum bite force affects craniofacial morphology and an organism's ability to break down foods with different material properties. Humans are generally believed to produce low bite forces and spend less time chewing compared with other apes because advances in mechanical and thermal food processing techniques alter food material properties in such a way as to reduce overall masticatory effort. However, when hominins began regularly consuming mechanically processed or cooked diets is not known. Here, we apply a model for estimating maximum bite forces and stresses at the second molar in modern human, nonhuman primate, and hominin skulls that incorporates skeletal data along with species-specific estimates of jaw muscle architecture. The model, which reliably estimates bite forces, shows a significant relationship between second molar bite force and second molar area across species but does not confirm our hypothesis of isometry. Specimens in the genus Homo fall below the regression line describing the relationship between bite force and molar area for nonhuman anthropoids and australopiths. These results suggest that Homo species generate maximum bite forces below those predicted based on scaling among australopiths and nonhuman primates. Because this decline occurred before evidence for cooking, we hypothesize that selection for lower bite force production was likely made possible by an increased reliance on nonthermal food processing. However, given substantial variability among in vivo bite force magnitudes measured in humans, environmental effects, especially variations in food mechanical properties, may also be a factor. The results also suggest that australopiths had ape-like bite force capabilities. Copyright © 2013 Wiley Periodicals, Inc.

  5. Configurational approach to identifying the earliest hominin butchers

    PubMed Central

    Domínguez-Rodrigo, Manuel; Pickering, Travis Rayne; Bunn, Henry T.

    2010-01-01

    The announcement of two approximately 3.4-million-y-old purportedly butchered fossil bones from the Dikika paleoanthropological research area (Lower Awash Valley, Ethiopia) could profoundly alter our understanding of human evolution. Butchering damage on the Dikika bones would imply that tool-assisted meat-eating began approximately 800,000 y before previously thought, based on butchered bones from 2.6- to 2.5-million-y-old sites at the Ethiopian Gona and Bouri localities. Further, the only hominin currently known from Dikika at approximately 3.4 Ma is Australopithecus afarensis, a temporally and geographically widespread species unassociated previously with any archaeological evidence of butchering. Our taphonomic configurational approach to assess the claims of A. afarensis butchery at Dikika suggests the claims of unexpectedly early butchering at the site are not warranted. The Dikika research group focused its analysis on the morphology of the marks in question but failed to demonstrate, through recovery of similarly marked in situ fossils, the exact provenience of the published fossils, and failed to note occurrences of random striae on the cortices of the published fossils (incurred through incidental movement of the defleshed specimens across and/or within their abrasive encasing sediments). The occurrence of such random striae (sometimes called collectively “trampling” damage) on the two fossils provide the configurational context for rejection of the claimed butchery marks. The earliest best evidence for hominin butchery thus remains at 2.6 to 2.5 Ma, presumably associated with more derived species than A. afarensis. PMID:21078985

  6. Multi-level human evolution: ecological patterns in hominin phylogeny.

    PubMed

    Parravicini, Andrea; Pievani, Telmo

    2016-06-20

    Evolution is a process that occurs at many different levels, from genes to ecosystems. Genetic variations and ecological pressures are hence two sides of the same coin; but due both to fragmentary evidence and to the influence of a gene-centered and gradualistic approach to evolutionary phenomena, the field of paleoanthropology has been slow to take the role of macro-evolutionary patterns (i.e. ecological and biogeographical at large scale) seriously. However, several very recent findings in paleoanthropology stress both climate instability and ecological disturbance as key factors affecting the highly branching hominin phylogeny, from the earliest hominins to the appearance of cognitively modern humans. Allopatric speciation due to geographic displacement, turnover-pulses of species, adaptive radiation, mosaic evolution of traits in several coeval species, bursts of behavioral innovation, serial dispersals out of Africa, are just some of the macro-evolutionary patterns emerging from the field. The multilevel approach to evolution proposed by paleontologist Niles Eldredge is adopted here as interpretative tool, and has yielded a larger picture of human evolution that integrates different levels of evolutionary change, from local adaptations in limited ecological niches to dispersal phenotypes able to colonize an unprecedented range of ecosystems. Changes in global climate and Earth's surface most greatly affected human evolution. Precisely because it is cognitively hard for us to appreciate the long-term common destiny we share with the whole biosphere, it is particularly valuable to highlight the accumulating evidence that human evolution has been deeply affected by global ecological changes that transformed our African continent of origin.

  7. Brains, teeth and life histories in hominins: a review.

    PubMed

    Bermúdez de Castro, José María; Modesto-Mata, Mario; Martinón-Torres, María

    2015-07-20

    The role of the brain in the somatic development, as well as in the establishment of the different variables of the life history pattern in vertebrates has been largely debated. Moreover, during the last thirty years, dental development has been used as a good proxy to infer different aspects of the life history in hominins, primarily due to the correlation that exists between age at first molar eruption and brain size in the order Primates. We review these questions using what is known about brain growth and maturation, dental development and life history pattern, mainly in Homo sapiens and Pan troglodytes. It has been assumed that the brain represents the pace-maker of our development. However, we consider that our particular phenotype is the result of a hierarchical genetic program modulated by epigenetic and environmental factors. The particular bauplan of any kind of organisms (e.g. primates) may explain the high correlation observed between different variables of its life history pattern, brain size or dental development. However, the correlation of these variables seems to be less reliable when dealing with low-rank taxonomical categories (i.e., species). We suggest that, while there is likely some relationship between the rate of somatic development and tooth development, our brain size and maturation (and, by extension, those of other species of the genus Homo) have derived towards a particular trajectory, with a unique pattern of prenatal and postnatal time and rate of growth and, particularly, with remarkable slow brain maturation. We suggest that extremely slow brain maturation could be a very recent acquisition of the last H. sapiens populations. Furthermore, our review of the literature suggests caution in drawing conclusions about aspects of the life history of the hominins from the information we can obtain from dental development in fossil specimens.

  8. Configurational approach to identifying the earliest hominin butchers.

    PubMed

    Domínguez-Rodrigo, Manuel; Pickering, Travis Rayne; Bunn, Henry T

    2010-12-07

    The announcement of two approximately 3.4-million-y-old purportedly butchered fossil bones from the Dikika paleoanthropological research area (Lower Awash Valley, Ethiopia) could profoundly alter our understanding of human evolution. Butchering damage on the Dikika bones would imply that tool-assisted meat-eating began approximately 800,000 y before previously thought, based on butchered bones from 2.6- to 2.5-million-y-old sites at the Ethiopian Gona and Bouri localities. Further, the only hominin currently known from Dikika at approximately 3.4 Ma is Australopithecus afarensis, a temporally and geographically widespread species unassociated previously with any archaeological evidence of butchering. Our taphonomic configurational approach to assess the claims of A. afarensis butchery at Dikika suggests the claims of unexpectedly early butchering at the site are not warranted. The Dikika research group focused its analysis on the morphology of the marks in question but failed to demonstrate, through recovery of similarly marked in situ fossils, the exact provenience of the published fossils, and failed to note occurrences of random striae on the cortices of the published fossils (incurred through incidental movement of the defleshed specimens across and/or within their abrasive encasing sediments). The occurrence of such random striae (sometimes called collectively "trampling" damage) on the two fossils provide the configurational context for rejection of the claimed butchery marks. The earliest best evidence for hominin butchery thus remains at 2.6 to 2.5 Ma, presumably associated with more derived species than A. afarensis.

  9. Fossil hominin ulnae and the forelimb of Paranthropus.

    PubMed

    McHenry, Henry M; Brown, Cassandra C; McHenry, Lindsay J

    2007-10-01

    The discovery of Pan in the Middle Pleistocene deposits of the Kapthurin Formation of the Tugen Hills (McBrearty and Jablonski: Nature 437 (2005) 105-108) inspires new interest in the search for other chimpanzee fossils in the East African Rift Valley. Craniodental evidence of an eastward excursion of chimpanzee populations in the Plio-Pleistocene goes undetected in other hominin sites, but one enigmatic postcranial fossil, the Olduvai Hominid 36 ulna, has many chimp-like features. Analyses by Aiello et al. (Aiello et al.: Am J Phys Anthropol 109 (1999) 89-110) reveal that it is similar to extant Pan in some respects, but it also has unique traits not seen in other hominoid species. They refer it to Paranthropus boisei. In this study, we reassess the affinities of OH 36 using a different data set that includes more recently discovered hominin fossils including those attributed to Paranthropus. Despite its superficial resemblance to modern Pan, our results agree with those of Aiello et al. (Aiello et al.: Am J Phys Anthropol 109 (1999) 89-110) that OH 36 is distinctly different from modern chimpanzees. By default, it is reasonable to assign this specimen to P. boisei, but it is not at all similar to other ulnae referred to this genus. Ulnae attributed to Paranthropus from South Africa, Kenya, and Ethiopia are morphologically more heterogeneous than those within species of large-bodied Hominoidea. Although there are many apparent shared derived traits justifying a monophyletic Paranthropus clade, most if not all of these traits are related to a single functional complex (hypermastication) that may have evolved in parallel and thereby constituting a paraphyletic group of species.

  10. Mandibular size and shape variation in the hominins at Dmanisi, Republic of Georgia.

    PubMed

    Skinner, Matthew M; Gordon, Adam D; Collard, Nicole J

    2006-07-01

    The hominin fossils of Dmanisi, Republic of Georgia, present an ideal means of assessing levels of skeletal size and shape variation in a fossil hypodigm belonging to the genus Homo because they have been recovered from a spatially and temporally restricted context. We compare variation in mandible size and shape at Dmanisi to that of extant hominoids and extinct hominins. We use height and breadth measurements of the mandibular corpus at the first molar and the symphysis to assess size, and analyze shape based on size-adjusted (using a geometric mean) versions of these four variables. We compare size and shape variation at Dmanisi relative to all possible pairs of individuals within each comparative taxon using an exact resampling procedure of the ratio of D2600 to D211 and the average Euclidean distance (AED) between D2600 and D211, respectively. Comparisons to extant hominoids were conducted at both the specific and subspecific taxonomic levels and to extinct hominins by adopting both a more, and less speciose, hominin taxonomy. Results indicate that the pattern of variation for the Dmanisi hominins does not resemble that of any living species: they exhibit significantly more size variation when compared to modern humans, and they have significantly more corpus shape variation and size variation in corpus heights and overall mandible size than any extant ape species. When compared to fossil hominins they are also more dimorphic in size (although this result is influenced by the taxonomic hypothesis applied to the hominin fossil record). These results highlight the need to re-examine expectations of levels of sexual dimorphism in members of the genus Homo and to account for marked size and shape variation between D2600 and D211 under the prevailing view of a single hominin species at Dmanisi.

  11. Evidence of fatal skeletal injuries on Malapa Hominins 1 and 2

    PubMed Central

    L’Abbé, Ericka N.; Symes, Steven A.; Pokines, James T.; Cabo, Luis L.; Stull, Kyra E.; Kuo, Sharon; Raymond, David E.; Randolph-Quinney, Patrick S.; Berger, Lee R.

    2015-01-01

    Malapa is one of the richest early hominin sites in Africa and the discovery site of the hominin species, Australopithecus sediba. The holotype and paratype (Malapa Hominin 1 and 2, or MH1 and MH2, respectively) skeletons are among the most complete in the early hominin record. Dating to approximately two million years BP, MH1 and MH2 are hypothesized to have fallen into a natural pit trap. All fractures evident on MH1 and MH2 skeletons were evaluated and separated based on wet and dry bone fracture morphology/characteristics. Most observed fractures are post-depositional, but those in the right upper limb of the adult hominin strongly indicate active resistance to an impact, while those in the juvenile hominin mandible are consistent with a blow to the face. The presence of skeletal trauma independently supports the falling hypothesis and supplies the first evidence for the manner of death of an australopith in the fossil record that is not attributed to predation or natural death. PMID:26459912

  12. Luminescence dating and palaeomagnetic age constraint on hominins from Sima de los Huesos, Atapuerca, Spain.

    PubMed

    Arnold, Lee J; Demuro, Martina; Parés, Josep M; Arsuaga, Juan Luis; Aranburu, Arantza; Bermúdez de Castro, José María; Carbonell, Eudald

    2014-02-01

    Establishing a reliable chronology on the extensive hominin remains at Sima de los Huesos is critical for an improved understanding of the complex evolutionary histories and phylogenetic relationships of the European Middle Pleistocene hominin record. In this study, we use a combination of 'extended-range' luminescence dating techniques and palaeomagnetism to provide new age constraint on sedimentary infills that are unambiguously associated with the Sima fossil assemblage. Post-infrared-infrared stimulated luminescence (pIR-IR) dating of K-feldspars and thermally transferred optically stimulated luminescence (TT-OSL) dating of individual quartz grains provide weighted mean ages of 433 ± 15 ka (thousands of years) and 416 ± 19 ka, respectively, for allochthonous sedimentary horizons overlying the hominin-bearing clay breccia. The six replicate luminescence ages obtained for this deposit are reproducible and provide a combined minimum age estimate of 427 ± 12 ka for the underlying hominin fossils. Palaeomagnetic directions for the luminescence dated sediment horizon and underlying fossiliferous clays display exclusively normal polarities. These findings are consistent with the luminescence dating results and confirm that the hominin fossil horizon accumulated during the Brunhes Chron, i.e., within the last 780 ka. The new bracketing age constraint for the Sima hominins is in broad agreement with radiometrically dated Homo heidelbergensis fossil sites, such as Mauer and Arago, and suggests that the split of the H. neanderthalensis and H. sapiens lineages took place during the early Middle Pleistocene. More widespread numerical dating of key Early and Middle Pleistocene fossil sites across Europe is needed to test and refine competing models of hominin evolution. The new luminescence chronologies presented in this study demonstrate the versatility of TT-OSL and pIR-IR techniques and the potential role they could play in helping to refine evolutionary

  13. Brief communication: Lumbar lordosis in extinct hominins: implications of the pelvic incidence.

    PubMed

    Been, Ella; Gómez-Olivencia, Asier; Kramer, Patricia A

    2014-06-01

    Recently, interest has peaked regarding the posture of extinct hominins. Here, we present a new method of reconstructing lordosis angles of extinct hominin specimens based on pelvic morphology, more specifically the orientation of the sacrum in relation to the acetabulum (pelvic incidence). Two regression models based on the correlation between pelvic incidence and lordosis angle in living hominoids have been developed. The mean values of the calculated lordosis angles based on these models are 36°-45° for australopithecines, 45°-47° for Homo erectus, 27°-34° for the Neandertals and the Sima de los Huesos hominins, and 49°-51° for fossil H. sapiens. The newly calculated lordosis values are consistent with previously published values of extinct hominins (Been et al.: Am J Phys Anthropol 147 (2012) 64-77). If the mean values of the present nonhuman hominoids are representative of the pelvic and lumbar morphology of the last common ancestor between humans and nonhuman hominoids, then both pelvic incidence and lordosis angle dramatically increased during hominin evolution from 27° ± 5 to 22° ± 3 (respectively) in nonhuman hominoids to 54° ± 10 and 51° ± 11 in modern humans. This change to a more human-like configuration appeared early in the hominin evolution as the pelvis and spines of both australopithecines and H. erectus show a higher pelvic incidence and lordosis angle than nonhuman hominoids. The Sima de los Huesos hominins and Neandertals show a derived configuration with a low pelvic incidence and lordosis angle.

  14. Body size and body shape in early hominins - implications of the Gona pelvis.

    PubMed

    Ruff, Christopher

    2010-02-01

    Discovery of the first complete Early Pleistocene hominin pelvis, Gona BSN49/P27, attributed to Homo erectus, raises a number of issues regarding early hominin body size and shape variation. Here, acetabular breadth, femoral head breadth, and body mass calculated from femoral head breadth are compared in 37 early hominin (6.0-0.26 Ma) specimens, including BSN49/P27. Acetabular and estimated femoral head sizes in the Gona specimen fall close to the means for non-Homo specimens (Orrorin tugenesis, Australopithecus africanus, Paranthropus robustus), and well below the ranges of all previously described Early and Middle Pleistocene Homo specimens. The Gona specimen has an estimated body mass of 33.2kg, close to the mean for the non-Homo sample (34.1kg, range 24-51.5kg, n=19) and far outside the range for any previously known Homo specimen (mean=70.5kg; range 52-82kg, n=17). Inclusion of the Gona specimen within H. erectus increases inferred sexual dimorphism in body mass in this taxon to a level greater than that observed here for any other hominin taxon, and increases variation in body mass within H. erectus females to a level much greater than that observed for any living primate species. This raises questions regarding the taxonomic attribution of the Gona specimen. When considered within the context of overall variation in body breadth among early hominins, the mediolaterally very wide Gona pelvis fits within the distribution of other lower latitude Early and Middle Pleistocene specimens, and below that of higher latitude specimens. Thus, ecogeographic variation in body breadth was present among earlier hominins as it is in living humans. The increased M-L pelvic breadth in all earlier hominins relative to modern humans is related to an increase in ellipticity of the birth canal, possibly as a result of a non-rotational birth mechanism that was common to both australopithecines and archaic Homo.

  15. An astronomically-tuned climate framework for hominins in the Turkana Basin

    NASA Astrophysics Data System (ADS)

    Joordens, Josephine C. A.; Vonhof, Hubert B.; Feibel, Craig S.; Lourens, Lucas J.; Dupont-Nivet, Guillaume; van der Lubbe, Jeroen H. J. L.; Sier, Mark J.; Davies, Gareth R.; Kroon, Dick

    2011-07-01

    Understanding the influence of orbital climate cycles on hominin evolution remains a key challenge in paleoanthropology. The two major unresolved issues are: the absence of a climate proxy yielding high-resolution (< 20 kyr) terrestrial climate records, and the lack of age control on hominin fossil occurrences at sufficiently high resolution. Here we present a novel climate proxy, strontium isotope ratios ( 87Sr/ 86Sr) of lacustrine fish fossils from the Turkana Basin, that solves these issues by recording orbitally forced variation in summer monsoon intensity over the Ethiopian Highlands. We successfully applied the climate proxy to a ~ 150 kyr time interval of ~ 2 million year old paleolake deposits containing hominin fossils. Existing age control of the studied interval was improved by a new magnetostratigraphic record precisely locating the base of the Olduvai chron (C2n) near the bottom of the sequence. Spectral analysis demonstrates that 87Sr/ 86Sr variability is primarily determined by precession, which enables us to place hominin fossils in an astronomically-tuned climate framework. The Sr climate proxy is potentially applicable to all hominin-bearing lake deposits in the Turkana Basin, ranging in age from ~ 4.2 to 0.8 million years ago (Ma). Our results demonstrate that between ~ 2 and 1.85 Ma the Turkana Basin remained well-watered and inhabited by hominins even during periods of precession maxima when summer monsoon intensity was lowest. This is in contrast to other basins in the East African Rift System (EARS) that were impacted heavily by precession-forced droughts. We hypothesize that during lake phases, the Turkana Basin was an aridity refugium for permanent-water dependent fauna - including hominins - over the precessional climate cycles.

  16. The Evolution and Functional Impact of Human Deletion Variants Shared with Archaic Hominin Genomes

    PubMed Central

    Lin, Yen-Lung; Pavlidis, Pavlos; Karakoc, Emre; Ajay, Jerry; Gokcumen, Omer

    2015-01-01

    Allele sharing between modern and archaic hominin genomes has been variously interpreted to have originated from ancestral genetic structure or through non-African introgression from archaic hominins. However, evolution of polymorphic human deletions that are shared with archaic hominin genomes has yet to be studied. We identified 427 polymorphic human deletions that are shared with archaic hominin genomes, approximately 87% of which originated before the Human–Neandertal divergence (ancient) and only approximately 9% of which have been introgressed from Neandertals (introgressed). Recurrence, incomplete lineage sorting between human and chimp lineages, and hominid-specific insertions constitute the remaining approximately 4% of allele sharing between humans and archaic hominins. We observed that ancient deletions correspond to more than 13% of all common (>5% allele frequency) deletion variation among modern humans. Our analyses indicate that the genomic landscapes of both ancient and introgressed deletion variants were primarily shaped by purifying selection, eliminating large and exonic variants. We found 17 exonic deletions that are shared with archaic hominin genomes, including those leading to three fusion transcripts. The affected genes are involved in metabolism of external and internal compounds, growth and sperm formation, as well as susceptibility to psoriasis and Crohn’s disease. Our analyses suggest that these “exonic” deletion variants have evolved through different adaptive forces, including balancing and population-specific positive selection. Our findings reveal that genomic structural variants that are shared between humans and archaic hominin genomes are common among modern humans and can influence biomedically and evolutionarily important phenotypes. PMID:25556237

  17. Insights into hominin phenotypic and dietary evolution from ancient DNA sequence data.

    PubMed

    Perry, George H; Kistler, Logan; Kelaita, Mary A; Sams, Aaron J

    2015-02-01

    Nuclear genome sequence data from Neandertals, Denisovans, and archaic anatomically modern humans can be used to complement our understanding of hominin evolutionary biology and ecology through i) direct inference of archaic hominin phenotypes, ii) indirect inference of those phenotypes by identifying the effects of previously-introgressed alleles still present among modern humans, or iii) determining the evolutionary timing of relevant hominin-specific genetic changes. Here we review and reanalyze published Neandertal and Denisovan genome sequence data to illustrate an example of the third approach. Specifically, we infer the timing of five human gene presence/absence changes that may be related to particular hominin-specific dietary changes and discuss these results in the context of our broader reconstructions of hominin evolutionary ecology. We show that pseudogenizing (gene loss) mutations in the TAS2R62 and TAS2R64 bitter taste receptor genes and the MYH16 masticatory myosin gene occurred after the hominin-chimpanzee divergence but before the divergence of the human and Neandertal/Denisovan lineages. The absence of a functional MYH16 protein may explain our relatively reduced jaw muscles; this gene loss may have followed the adoption of cooking behavior. In contrast, salivary amylase gene (AMY1) duplications were not observed in the Neandertal and Denisovan genomes, suggesting a relatively recent origin for the AMY1 copy number gains that are observed in modern humans. Thus, if earlier hominins were consuming large quantities of starch-rich underground storage organs, as previously hypothesized, then they were likely doing so without the digestive benefits of increased salivary amylase production. Our most surprising result was the observation of a heterozygous mutation in the first codon of the TAS2R38 bitter taste receptor gene in the Neandertal individual, which likely would have resulted in a non-functional protein and inter-individual PTC

  18. The waiting time problem in a model hominin population.

    PubMed

    Sanford, John; Brewer, Wesley; Smith, Franzine; Baumgardner, John

    2015-09-17

    Functional information is normally communicated using specific, context-dependent strings of symbolic characters. This is true within the human realm (texts and computer programs), and also within the biological realm (nucleic acids and proteins). In biology, strings of nucleotides encode much of the information within living cells. How do such information-bearing nucleotide strings arise and become established? This paper uses comprehensive numerical simulation to understand what types of nucleotide strings can realistically be established via the mutation/selection process, given a reasonable timeframe. The program Mendel's Accountant realistically simulates the mutation/selection process, and was modified so that a starting string of nucleotides could be specified, and a corresponding target string of nucleotides could be specified. We simulated a classic pre-human hominin population of at least 10,000 individuals, with a generation time of 20 years, and with very strong selection (50% selective elimination). Random point mutations were generated within the starting string. Whenever an instance of the target string arose, all individuals carrying the target string were assigned a specified reproductive advantage. When natural selection had successfully amplified an instance of the target string to the point of fixation, the experiment was halted, and the waiting time statistics were tabulated. Using this methodology we tested the effect of mutation rate, string length, fitness benefit, and population size on waiting time to fixation. Biologically realistic numerical simulations revealed that a population of this type required inordinately long waiting times to establish even the shortest nucleotide strings. To establish a string of two nucleotides required on average 84 million years. To establish a string of five nucleotides required on average 2 billion years. We found that waiting times were reduced by higher mutation rates, stronger fitness benefits, and

  19. Hominin track assemblages from Okote Member deposits near Ileret, Kenya, and their implications for understanding fossil hominin paleobiology at 1.5 Ma.

    PubMed

    Hatala, Kevin G; Roach, Neil T; Ostrofsky, Kelly R; Wunderlich, Roshna E; Dingwall, Heather L; Villmoare, Brian A; Green, David J; Braun, David R; Harris, John W K; Behrensmeyer, Anna K; Richmond, Brian G

    2017-09-13

    Tracks can provide unique, direct records of behaviors of fossil organisms moving across their landscapes millions of years ago. While track discoveries have been rare in the human fossil record, over the last decade our team has uncovered multiple sediment surfaces within the Okote Member of the Koobi Fora Formation near Ileret, Kenya that contain large assemblages of ∼1.5 Ma fossil hominin tracks. Here, we provide detailed information on the context and nature of each of these discoveries, and we outline the specific data that are preserved on the Ileret hominin track surfaces. We analyze previously unpublished data to refine and expand upon earlier hypotheses regarding implications for hominin anatomy and social behavior. While each of the track surfaces discovered at Ileret preserves a different amount of data that must be handled in particular ways, general patterns are evident. Overall, the analyses presented here support earlier interpretations of the ∼1.5 Ma Ileret track assemblages, providing further evidence of large, human-like body sizes and possibly evidence of a group composition that could support the emergence of certain human-like patterns of social behavior. These data, used in concert with other forms of paleontological and archaeological evidence that are deposited on different temporal scales, offer unique windows through which we can broaden our understanding of the paleobiology of hominins living in East Africa at ∼1.5 Ma. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Loss of Olfactory Receptor Function in Hominin Evolution

    PubMed Central

    Hughes, Graham M.; Teeling, Emma C.; Higgins, Desmond G.

    2014-01-01

    The mammalian sense of smell is governed by the largest gene family, which encodes the olfactory receptors (ORs). The gain and loss of OR genes is typically correlated with adaptations to various ecological niches. Modern humans have 853 OR genes but 55% of these have lost their function. Here we show evidence of additional OR loss of function in the Neanderthal and Denisovan hominin genomes using comparative genomic methodologies. Ten Neanderthal and 8 Denisovan ORs show evidence of loss of function that differ from the reference modern human OR genome. Some of these losses are also present in a subset of modern humans, while some are unique to each lineage. Morphological changes in the cranium of Neanderthals suggest different sensory arrangements to that of modern humans. We identify differences in functional olfactory receptor genes among modern humans, Neanderthals and Denisovans, suggesting varied loss of function across all three taxa and we highlight the utility of using genomic information to elucidate the sensory niches of extinct species. PMID:24392153

  1. Loss of olfactory receptor function in hominin evolution.

    PubMed

    Hughes, Graham M; Teeling, Emma C; Higgins, Desmond G

    2014-01-01

    The mammalian sense of smell is governed by the largest gene family, which encodes the olfactory receptors (ORs). The gain and loss of OR genes is typically correlated with adaptations to various ecological niches. Modern humans have 853 OR genes but 55% of these have lost their function. Here we show evidence of additional OR loss of function in the Neanderthal and Denisovan hominin genomes using comparative genomic methodologies. Ten Neanderthal and 8 Denisovan ORs show evidence of loss of function that differ from the reference modern human OR genome. Some of these losses are also present in a subset of modern humans, while some are unique to each lineage. Morphological changes in the cranium of Neanderthals suggest different sensory arrangements to that of modern humans. We identify differences in functional olfactory receptor genes among modern humans, Neanderthals and Denisovans, suggesting varied loss of function across all three taxa and we highlight the utility of using genomic information to elucidate the sensory niches of extinct species.

  2. Middle Pliocene hominin diversity: Australopithecus deyiremeda and Kenyanthropus platyops

    PubMed Central

    Spoor, Fred; Leakey, Meave G.; O'Higgins, Paul

    2016-01-01

    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. This article is part of the themed issue ‘Major transitions in human evolution’. PMID:27298462

  3. Food material properties and early hominin processing techniques.

    PubMed

    Zink, Katherine D; Lieberman, Daniel E; Lucas, Peter W

    2014-12-01

    Although early Homo is hypothesized to have used tools more than australopiths to process foods prior to consumption, it is unknown how much the food processing techniques they used altered the material properties of foods, and therefore the masticatory forces they generated, and how well they were able to comminute foods. This study presents experimental data on changes to food material properties caused by mechanical tenderization (pounding with a stone tool) and cooking (dry roasting) of two foods likely to have been important components of the hominin diet: meat and tubers. Mechanical tenderization significantly decreased tuber toughness by 42%, but had no effect on meat toughness. Roasting significantly decreased several material properties of tubers correlated with masticatory effort including toughness (49%), fracture stress (28%) and elastic modulus (45%), but increased the toughness (77%), fracture stress (50%-222%), and elastic modulus of muscle fibers in meat (308%). Despite increasing many material properties of meat associated with higher masticatory forces, roasting also decreased measured energy loss by 28%, which likely makes it easier to chew. These results suggest that the use of food processing techniques by early Homo probably differed for meat and tubers, but together would have reduced masticatory effort, helping to relax selection to maintain large, robust faces and large, thickly enameled teeth.

  4. Middle Pliocene hominin diversity: Australopithecus deyiremeda and Kenyanthropus platyops.

    PubMed

    Spoor, Fred; Leakey, Meave G; O'Higgins, Paul

    2016-07-05

    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.This article is part of the themed issue 'Major transitions in human evolution'.

  5. 'Captivity bias' in animal tool use and its implications for the evolution of hominin technology.

    PubMed

    Haslam, Michael

    2013-11-19

    Animals in captive or laboratory settings may outperform wild animals of the same species in both frequency and diversity of tool use, a phenomenon here termed 'captivity bias'. Although speculative at this stage, a logical conclusion from this concept is that animals whose tool-use behaviour is observed solely under natural conditions may be judged cognitively or physically inferior than if they had also been tested or observed under controlled captive conditions. In turn, this situation creates a potential problem for studies of the behaviour of extinct members of the human family tree-the hominins-as hominin cognitive abilities are often judged on material evidence of tool-use behaviour left in the archaeological record. In this review, potential factors contributing to captivity bias in primates (including increased contact between individuals engaged in tool use, guidance or shaping of tool-use behaviour by other tool-users and increased free time and energy) are identified and assessed for their possible effects on the behaviour of the Late Pleistocene hominin Homo floresiensis. The captivity bias concept provides one way to uncouple hominin tool use from cognition, by considering hominins as subject to the same adaptive influences as other tool-using animals.

  6. Landscapes of human evolution: models and methods of tectonic geomorphology and the reconstruction of hominin landscapes.

    PubMed

    Bailey, Geoffrey N; Reynolds, Sally C; King, Geoffrey C P

    2011-03-01

    This paper examines the relationship between complex and tectonically active landscapes and patterns of human evolution. We show how active tectonics can produce dynamic landscapes with geomorphological and topographic features that may be critical to long-term patterns of hominin land use, but which are not typically addressed in landscape reconstructions based on existing geological and paleoenvironmental principles. We describe methods of representing topography at a range of scales using measures of roughness based on digital elevation data, and combine the resulting maps with satellite imagery and ground observations to reconstruct features of the wider landscape as they existed at the time of hominin occupation and activity. We apply these methods to sites in South Africa, where relatively stable topography facilitates reconstruction. We demonstrate the presence of previously unrecognized tectonic effects and their implications for the interpretation of hominin habitats and land use. In parts of the East African Rift, reconstruction is more difficult because of dramatic changes since the time of hominin occupation, while fossils are often found in places where activity has now almost ceased. However, we show that original, dynamic landscape features can be assessed by analogy with parts of the Rift that are currently active and indicate how this approach can complement other sources of information to add new insights and pose new questions for future investigation of hominin land use and habitats. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. Brain enlargement and dental reduction were not linked in hominin evolution

    PubMed Central

    Smaers, Jeroen B.; Holloway, Ralph L.

    2017-01-01

    The large brain and small postcanine teeth of modern humans are among our most distinctive features, and trends in their evolution are well studied within the hominin clade. Classic accounts hypothesize that larger brains and smaller teeth coevolved because behavioral changes associated with increased brain size allowed a subsequent dental reduction. However, recent studies have found mismatches between trends in brain enlargement and posterior tooth size reduction in some hominin species. We use a multiple-variance Brownian motion approach in association with evolutionary simulations to measure the tempo and mode of the evolution of endocranial and dental size and shape within the hominin clade. We show that hominin postcanine teeth have evolved at a relatively consistent neutral rate, whereas brain size evolved at comparatively more heterogeneous rates that cannot be explained by a neutral model, with rapid pulses in the branches leading to later Homo species. Brain reorganization shows evidence of elevated rates only much later in hominin evolution, suggesting that fast-evolving traits such as the acquisition of a globular shape may be the result of direct or indirect selection for functional or structural traits typical of modern humans. PMID:28049819

  8. Oldest Evidence of Toolmaking Hominins in a Grassland-Dominated Ecosystem

    PubMed Central

    Plummer, Thomas W.; Ditchfield, Peter W.; Bishop, Laura C.; Kingston, John D.; Ferraro, Joseph V.; Braun, David R.; Hertel, Fritz; Potts, Richard

    2009-01-01

    Background Major biological and cultural innovations in late Pliocene hominin evolution are frequently linked to the spread or fluctuating presence of C4 grass in African ecosystems. Whereas the deep sea record of global climatic change provides indirect evidence for an increase in C4 vegetation with a shift towards a cooler, drier and more variable global climatic regime beginning approximately 3 million years ago (Ma), evidence for grassland-dominated ecosystems in continental Africa and hominin activities within such ecosystems have been lacking. Methodology/Principal Findings We report stable isotopic analyses of pedogenic carbonates and ungulate enamel, as well as faunal data from ∼2.0 Ma archeological occurrences at Kanjera South, Kenya. These document repeated hominin activities within a grassland-dominated ecosystem. Conclusions/Significance These data demonstrate what hitherto had been speculated based on indirect evidence: that grassland-dominated ecosystems did in fact exist during the Plio-Pleistocene, and that early Homo was active in open settings. Comparison with other Oldowan occurrences indicates that by 2.0 Ma hominins, almost certainly of the genus Homo, used a broad spectrum of habitats in East Africa, from open grassland to riparian forest. This strongly contrasts with the habitat usage of Australopithecus, and may signal an important shift in hominin landscape usage. PMID:19844568

  9. Relevance of aquatic environments for hominins: a case study from Trinil (Java, Indonesia).

    PubMed

    Joordens, J C A; Wesselingh, F P; de Vos, J; Vonhof, H B; Kroon, D

    2009-12-01

    Knowledge about dietary niche is key to understanding hominin evolution, since diet influences body proportions, brain size, cognition, and habitat preference. In this study we provide ecological context for the current debate on modernity (or not) of aquatic resource exploitation by hominins. We use the Homo erectus site of Trinil as a case study to investigate how research questions on possible dietary relevance of aquatic environments can be addressed. Faunal and geochemical analysis of aquatic fossils from Trinil Hauptknochenschicht (HK) fauna demonstrate that Trinil at approximately 1.5Ma contained near-coastal rivers, lakes, swamp forests, lagoons, and marshes with minor marine influence, laterally grading into grasslands. Trinil HK environments yielded at least eleven edible mollusc species and four edible fish species that could be procured with no or minimal technology. We demonstrate that, from an ecological point of view, the default assumption should be that omnivorous hominins in coastal habitats with catchable aquatic fauna could have consumed aquatic resources. The hypothesis of aquatic exploitation can be tested with taphonomic analysis of aquatic fossils associated with hominin fossils. We show that midden-like characteristics of large bivalve shell assemblages containing Pseudodon and Elongaria from Trinil HK indicate deliberate collection by a selective agent, possibly hominin.

  10. New footprints from Laetoli (Tanzania) provide evidence for marked body size variation in early hominins

    PubMed Central

    Masao, Fidelis T; Ichumbaki, Elgidius B; Cherin, Marco; Barili, Angelo; Boschian, Giovanni; Iurino, Dawid A; Menconero, Sofia; Moggi-Cecchi, Jacopo; Manzi, Giorgio

    2016-01-01

    Laetoli is a well-known palaeontological locality in northern Tanzania whose outstanding record includes the earliest hominin footprints in the world (3.66 million years old), discovered in 1978 at Site G and attributed to Australopithecus afarensis. Here, we report hominin tracks unearthed in the new Site S at Laetoli and referred to two bipedal individuals (S1 and S2) moving on the same palaeosurface and in the same direction as the three hominins documented at Site G. The stature estimates for S1 greatly exceed those previously reconstructed for Au. afarensis from both skeletal material and footprint data. In combination with a comparative reappraisal of the Site G footprints, the evidence collected here embodies very important additions to the Pliocene record of hominin behaviour and morphology. Our results are consistent with considerable body size variation and, probably, degree of sexual dimorphism within a single species of bipedal hominins as early as 3.66 million years ago. DOI: http://dx.doi.org/10.7554/eLife.19568.001 PMID:27964778

  11. Brains, innovations, tools and cultural transmission in birds, non-human primates, and fossil hominins

    PubMed Central

    Lefebvre, Louis

    2013-01-01

    Recent work on birds and non-human primates has shown that taxonomic differences in field measures of innovation, tool use and social learning are associated with size of the mammalian cortex and avian mesopallium and nidopallium, as well as ecological traits like colonization success. Here, I review this literature and suggest that many of its findings are relevant to hominin intelligence. In particular, our large brains and increased intelligence may be partly independent of our ape phylogeny and the result of convergent processes similar to those that have molded avian and platyrrhine intelligence. Tool use, innovativeness and cultural transmission might be linked over our past and in our brains as operations of domain-general intelligence. Finally, colonization of new areas may have accompanied increases in both brain size and innovativeness in hominins as they have in other mammals and in birds, potentially accelerating hominin evolution via behavioral drive. PMID:23761751

  12. Animal movements in the Kenya Rift and evidence for the earliest ambush hunting by hominins

    NASA Astrophysics Data System (ADS)

    Kübler, Simon; Owenga, Peter; Reynolds, Sally C.; Rucina, Stephen M.; King, Geoffrey C. P.

    2015-09-01

    Animal movements in the Kenya Rift Valley today are influenced by a combination of topography and trace nutrient distribution. These patterns would have been the same in the past when hominins inhabited the area. We use this approach to create a landscape reconstruction of Olorgesailie, a key site in the East African Rift with abundant evidence of large-mammal butchery between ~1.2 and ~0.5 Ma BP. The site location in relation to limited animal routes through the area show that hominins were aware of animal movements and used the location for ambush hunting during the Lower to Middle Pleistocene. These features explain the importance of Olorgesailie as a preferred location of repeated hominin activity through multiple changes in climate and local environmental conditions, and provide insights into the cognitive and hunting abilities of Homo erectus while indicating that their activities at the site were aimed at hunting, rather than scavenging.

  13. A new small-bodied hominin from the Late Pleistocene of Flores, Indonesia.

    PubMed

    Brown, P; Sutikna, T; Morwood, M J; Soejono, R P; Jatmiko; Saptomo, E Wayhu; Due, Rokus Awe

    2004-10-28

    Currently, it is widely accepted that only one hominin genus, Homo, was present in Pleistocene Asia, represented by two species, Homo erectus and Homo sapiens. Both species are characterized by greater brain size, increased body height and smaller teeth relative to Pliocene Australopithecus in Africa. Here we report the discovery, from the Late Pleistocene of Flores, Indonesia, of an adult hominin with stature and endocranial volume approximating 1 m and 380 cm3, respectively--equal to the smallest-known australopithecines. The combination of primitive and derived features assigns this hominin to a new species, Homo floresiensis. The most likely explanation for its existence on Flores is long-term isolation, with subsequent endemic dwarfing, of an ancestral H. erectus population. Importantly, H. floresiensis shows that the genus Homo is morphologically more varied and flexible in its adaptive responses than previously thought.

  14. Animal movements in the Kenya Rift and evidence for the earliest ambush hunting by hominins

    PubMed Central

    Kübler, Simon; Owenga, Peter; Reynolds, Sally C.; Rucina, Stephen M.; King, Geoffrey C. P.

    2015-01-01

    Animal movements in the Kenya Rift Valley today are influenced by a combination of topography and trace nutrient distribution. These patterns would have been the same in the past when hominins inhabited the area. We use this approach to create a landscape reconstruction of Olorgesailie, a key site in the East African Rift with abundant evidence of large-mammal butchery between ~1.2 and ~0.5 Ma BP. The site location in relation to limited animal routes through the area show that hominins were aware of animal movements and used the location for ambush hunting during the Lower to Middle Pleistocene. These features explain the importance of Olorgesailie as a preferred location of repeated hominin activity through multiple changes in climate and local environmental conditions, and provide insights into the cognitive and hunting abilities of Homo erectus while indicating that their activities at the site were aimed at hunting, rather than scavenging. PMID:26369499

  15. Brains, innovations, tools and cultural transmission in birds, non-human primates, and fossil hominins.

    PubMed

    Lefebvre, Louis

    2013-01-01

    Recent work on birds and non-human primates has shown that taxonomic differences in field measures of innovation, tool use and social learning are associated with size of the mammalian cortex and avian mesopallium and nidopallium, as well as ecological traits like colonization success. Here, I review this literature and suggest that many of its findings are relevant to hominin intelligence. In particular, our large brains and increased intelligence may be partly independent of our ape phylogeny and the result of convergent processes similar to those that have molded avian and platyrrhine intelligence. Tool use, innovativeness and cultural transmission might be linked over our past and in our brains as operations of domain-general intelligence. Finally, colonization of new areas may have accompanied increases in both brain size and innovativeness in hominins as they have in other mammals and in birds, potentially accelerating hominin evolution via behavioral drive.

  16. Possible Signatures of Hominin Hybridization from the Early Holocene of Southwest China

    PubMed Central

    Curnoe, Darren; Ji, Xueping; Taçon, Paul S. C.; Yaozheng, Ge

    2015-01-01

    We have previously described hominin remains with numerous archaic traits from two localities (Maludong and Longlin Cave) in Southwest China dating to the Pleistocene-Holocene transition. If correct, this finding has important implications for understanding the late phases of human evolution. Alternative interpretations have suggested these fossils instead fit within the normal range of variation for early modern humans in East Asia. Here we test this proposition, consider the role of size-shape scaling, and more broadly assess the affinities of the Longlin 1 (LL1) cranium by comparing it to modern human and archaic hominin crania. The shape of LL1 is found to be highly unusual, but on balance shows strongest affinities to early modern humans, lacking obvious similarities to early East Asians specifically. We conclude that a scenario of hybridization with archaic hominins best explains the highly unusual morphology of LL1, possibly even occurring as late as the early Holocene. PMID:26202835

  17. Animal movements in the Kenya Rift and evidence for the earliest ambush hunting by hominins.

    PubMed

    Kübler, Simon; Owenga, Peter; Reynolds, Sally C; Rucina, Stephen M; King, Geoffrey C P

    2015-09-15

    Animal movements in the Kenya Rift Valley today are influenced by a combination of topography and trace nutrient distribution. These patterns would have been the same in the past when hominins inhabited the area. We use this approach to create a landscape reconstruction of Olorgesailie, a key site in the East African Rift with abundant evidence of large-mammal butchery between ~1.2 and ~0.5 Ma BP. The site location in relation to limited animal routes through the area show that hominins were aware of animal movements and used the location for ambush hunting during the Lower to Middle Pleistocene. These features explain the importance of Olorgesailie as a preferred location of repeated hominin activity through multiple changes in climate and local environmental conditions, and provide insights into the cognitive and hunting abilities of Homo erectus while indicating that their activities at the site were aimed at hunting, rather than scavenging.

  18. A new hominin foot from Ethiopia shows multiple Pliocene bipedal adaptations.

    PubMed

    Haile-Selassie, Yohannes; Saylor, Beverly Z; Deino, Alan; Levin, Naomi E; Alene, Mulugeta; Latimer, Bruce M

    2012-03-28

    A newly discovered partial hominin foot skeleton from eastern Africa indicates the presence of more than one hominin locomotor adaptation at the beginning of the Late Pliocene epoch. Here we show that new pedal elements, dated to about 3.4 million years ago, belong to a species that does not match the contemporaneous Australopithecus afarensis in its morphology and inferred locomotor adaptations, but instead are more similar to the earlier Ardipithecus ramidus in possessing an opposable great toe. This not only indicates the presence of more than one hominin species at the beginning of the Late Pliocene of eastern Africa, but also indicates the persistence of a species with Ar. ramidus-like locomotor adaptation into the Late Pliocene.

  19. The femur of Orrorin tugenensis exhibits morphometric affinities with both Miocene apes and later hominins.

    PubMed

    Almécija, Sergio; Tallman, Melissa; Alba, David M; Pina, Marta; Moyà-Solà, Salvador; Jungers, William L

    2013-01-01

    Orrorin tugenensis (Kenya, ca. 6 Ma) is one of the earliest putative hominins. Its proximal femur, BAR 1002'00, was originally described as being very human-like, although later multivariate analyses showed an australopith pattern. However, some of its traits (for example, laterally protruding greater trochanter, medially oriented lesser trochanter and presence of third trochanter) are also present in earlier Miocene apes. Here, we use geometric morphometrics to reassess the morphological affinities of BAR 1002'00 within a large sample of anthropoids (including fossil apes and hominins) and reconstruct hominoid proximal femur evolution using squared-change parsimony. Our results indicate that both hominin and modern great ape femora evolved in different directions from a primitive morphology represented by some fossil apes. Orrorin appears intermediate between Miocene apes and australopiths in shape space. This evidence is consistent with femoral shape similarities in extant great apes being derived and homoplastic and has profound implications for understanding the origins of human bipedalism.

  20. Possible Signatures of Hominin Hybridization from the Early Holocene of Southwest China.

    PubMed

    Curnoe, Darren; Ji, Xueping; Taçon, Paul S C; Yaozheng, Ge

    2015-07-23

    We have previously described hominin remains with numerous archaic traits from two localities (Maludong and Longlin Cave) in Southwest China dating to the Pleistocene-Holocene transition. If correct, this finding has important implications for understanding the late phases of human evolution. Alternative interpretations have suggested these fossils instead fit within the normal range of variation for early modern humans in East Asia. Here we test this proposition, consider the role of size-shape scaling, and more broadly assess the affinities of the Longlin 1 (LL1) cranium by comparing it to modern human and archaic hominin crania. The shape of LL1 is found to be highly unusual, but on balance shows strongest affinities to early modern humans, lacking obvious similarities to early East Asians specifically. We conclude that a scenario of hybridization with archaic hominins best explains the highly unusual morphology of LL1, possibly even occurring as late as the early Holocene.

  1. Potential hominin affinities of Graecopithecus from the Late Miocene of Europe.

    PubMed

    Fuss, Jochen; Spassov, Nikolai; Begun, David R; Böhme, Madelaine

    2017-01-01

    The split of our own clade from the Panini is undocumented in the fossil record. To fill this gap we investigated the dentognathic morphology of Graecopithecus freybergi from Pyrgos Vassilissis (Greece) and cf. Graecopithecus sp. from Azmaka (Bulgaria), using new μCT and 3D reconstructions of the two known specimens. Pyrgos Vassilissis and Azmaka are currently dated to the early Messinian at 7.175 Ma and 7.24 Ma. Mainly based on its external preservation and the previously vague dating, Graecopithecus is often referred to as nomen dubium. The examination of its previously unknown dental root and pulp canal morphology confirms the taxonomic distinction from the significantly older northern Greek hominine Ouranopithecus. Furthermore, it shows features that point to a possible phylogenetic affinity with hominins. G. freybergi uniquely shares p4 partial root fusion and a possible canine root reduction with this tribe and therefore, provides intriguing evidence of what could be the oldest known hominin.

  2. The evolutionary history of the hominin hand since the last common ancestor of Pan and Homo

    PubMed Central

    Tocheri, Matthew W; Orr, Caley M; Jacofsky, Marc C; Marzke, Mary W

    2008-01-01

    Molecular evidence indicates that the last common ancestor of the genus Pan and the hominin clade existed between 8 and 4 million years ago (Ma). The current fossil record indicates the Pan-Homo last common ancestor existed at least 5 Ma and most likely between 6 and 7 Ma. Together, the molecular and fossil evidence has important consequences for interpreting the evolutionary history of the hand within the tribe Hominini (hominins). Firstly, parsimony supports the hypothesis that the hand of the last common ancestor most likely resembled that of an extant great ape overall (Pan, Gorilla, and Pongo), and that of an African ape in particular. Second, it provides a context for interpreting the derived changes to the hand that have evolved in various hominins. For example, the Australopithecus afarensis hand is likely derived in comparison with that of the Pan–Homo last common ancestor in having shorter fingers relative to thumb length and more proximo-distally oriented joints between its capitate, second metacarpal, and trapezium. This evidence suggests that these derived features evolved prior to the intensification of stone tool-related hominin behaviors beginning around 2.5 Ma. However, a majority of primitive features most likely present in the Pan-Homo last common ancestor are retained in the hands of Australopithecus, Paranthropus/early Homo, and Homo floresiensis. This evidence suggests that further derived changes to the hands of other hominins such as modern humans and Neandertals did not evolve until after 2.5 Ma and possibly even later than 1.5 Ma, which is currently the earliest evidence of Acheulian technology. The derived hands of modern humans and Neandertals may indicate a morphological commitment to tool-related manipulative behaviors beyond that observed in other hominins, including those (e.g. H. floresiensis) which may be descended from earlier tool-making species. PMID:18380869

  3. Vegetation context and climatic limits of the Early Pleistocene hominin dispersal in Europe

    NASA Astrophysics Data System (ADS)

    Leroy, S. A. G.; Arpe, K.; Mikolajewicz, U.

    2011-06-01

    The vegetation and the climatic context in which the first hominins entered and dispersed in Europe during the Early Pleistocene are reconstructed, using literature review and a new climatic simulation. Both in situ fauna and in situ pollen at the twelve early hominin sites under consideration indicate the occurrence of open landscapes: grasslands or forested steppes. The presence of ancient hominins ( Homo of the erectus group) in Europe is only possible at the transition from glacial to interglacial periods, the full glacial being too cold for them and the transition interglacial to glacial too forested. Glacial-interglacial cycles forced by obliquity showed paralleled vegetation successions, which repeated c. 42 times during the course of the Early Pleistocene (2.58-0.78 Ma), providing 42 narrow windows of opportunity for hominins to disperse into Europe. The climatic conditions of this Early Pleistocene vegetation at glacial-interglacial transitions are compared with a climatic simulation for 9 ka ago without ice sheet, as this time period is so far the best analogue available. The climate at the beginning of the present interglacial displayed a stronger seasonality than now. Forest cover would not have been hampered though, clearly indicating that other factors linked to refugial location and soils leave this period relatively free of forests. Similar situations with an offset between climate and vegetation at the beginning of interglacials repeated themselves throughout the Quaternary and benefitted the early hominins when colonising Europe. The duration of this open phase of vegetation at the glacial-interglacial transition was long enough to allow colonisation from the Levant to the Atlantic. The twelve sites fall within rather narrow ranges of summer precipitation and temperature of the coldest month, suggesting the hominins had only a very low tolerance to climate variability.

  4. Shallow-water habitats as sources of fallback foods for hominins.

    PubMed

    Wrangham, Richard; Cheney, Dorothy; Seyfarth, Robert; Sarmiento, Esteban

    2009-12-01

    Underground storage organs (USOs) have been proposed as critical fallback foods for early hominins in savanna, but there has been little discussion as to which habitats would have been important sources of USOs. USOs consumed by hominins could have included both underwater and underground storage organs, i.e., from both aquatic and terrestrial habitats. Shallow aquatic habitats tend to offer high plant growth rates, high USO densities, and relatively continuous USO availability throughout the year. Baboons in the Okavango delta use aquatic USOs as a fallback food, and aquatic or semiaquatic USOs support high-density human populations in various parts of the world. As expected given fossilization requisites, the African early- to mid-Pleistocene shows an association of Homo and Paranthropus fossils with shallow-water and flooded habitats where high densities of plant-bearing USOs are likely to have occurred. Given that early hominins in the tropics lived in relatively dry habitats, while others occupied temperate latitudes, ripe, fleshy fruits of the type preferred by African apes would not normally have been available year round. We therefore suggest that water-associated USOs were likely to have been key fallback foods, and that dry-season access to aquatic habitats would have been an important predictor of hominin home range quality. This study differs from traditional savanna chimpanzee models of hominin origins by proposing that access to aquatic habitats was a necessary condition for adaptation to savanna habitats. It also raises the possibility that harvesting efficiency in shallow water promoted adaptations for habitual bipedality in early hominins.

  5. Ecological implications of the relative rarity of fossil hominins at Laetoli.

    PubMed

    Su, Denise F; Harrison, Terry

    2008-10-01

    Hominins are a very rare component of the large-mammal fauna at Laetoli. Although no equivalent data are available for Hadar, the much higher count and relative abundance of hominins suggests that they may have been more common at the latter site. The apparent relative rarity of hominins at Laetoli may have significant implications for understanding the ecology of Australopithecus afarensis. However, it is essential to first assess the extent to which taphonomic variables might have been a contributing factor. Using data from fossil ruminants, we show that the survivability of skeletal elements at Laetoli relates to the extent to which they can resist carnivore scavenging and their likelihood of being entirely buried by volcanic ashes and tuffaceous sediments. The rarity of hominins at Laetoli is probably due in part to the influence of these two taphonomic factors. However, these factors cannot account entirely for the difference in hominin relative abundance between these two sites, and ecological differences were probably a contributing factor. The highest population densities of chimpanzees today occur in forest and closed woodland, with reduced densities in open woodland. If similar levels of population-density variation characterized A. afarensis, the differences between Hadar and Laetoli may relate to the quality/optimality of the habitats. Hadar was, in general, much more densely wooded and mesic than Laetoli, with permanent and substantial bodies of water. In contrast, Laetoli was predominantly a woodland-shrubland-grassland mosaic supported only by ephemeral streams and ponds. The apparent greater relative abundance of hominins at Hadar compared with Laetoli suggests that, like chimpanzees, A. afarensis may have been more successful in more densely wooded habitats. Compared with Hadar, Laetoli probably represented a less optimal habitat for the foraging and dietary behavior of A. afarensis, and this is reflected in their inferred lower abundance, density

  6. The first hominin from the early Pleistocene paleocave of Haasgat, South Africa

    PubMed Central

    Leece, AB; Kegley, Anthony D.T.; Lacruz, Rodrigo S.; Herries, Andy I.R.; Hemingway, Jason; Kgasi, Lazarus; Potze, Stephany

    2016-01-01

    Haasgat is a primate-rich fossil locality in the northeastern part of the Fossil Hominid Sites of South Africa UNESCO World Heritage Site. Here we report the first hominin identified from Haasgat, a partial maxillary molar (HGT 500), that was recovered from an ex situ calcified sediment block sampled from the locality. The in situ fossil bearing deposits of the Haasgat paleokarstic deposits are estimated to date to slightly older than 1.95 Ma based on magnetobiostratigraphy. This places the hominin specimen at a critical time period in South Africa that marks the last occurrence of Australopithecus around 1.98 Ma and the first evidence of Paranthropus and Homo in the region between ∼2.0 and 1.8 Ma. A comprehensive morphological evaluation of the Haasgat hominin molar was conducted against the current South African catalogue of hominin dental remains and imaging analyses using micro-CT, electron and confocal microscopy. The preserved occlusal morphology is most similar to Australopithecus africanus or early Homo specimens but different from Paranthropus. Occlusal linear enamel thickness measured from micro-CT scans provides an average of ∼2.0 mm consistent with Australopithecus and early Homo. Analysis of the enamel microstructure suggests an estimated periodicity of 7–9 days. Hunter–Schreger bands appear long and straight as in some Paranthropus, but contrast with this genus in the short shape of the striae of Retzius. Taken together, these data suggests that the maxillary fragment recovered from Haasgat best fits within the Australopithecus—early Homo hypodigms to the exclusion of the genus Paranthropus. At ∼1.95 Ma this specimen would either represent another example of late occurring Australopithecus or one of the earliest examples of Homo in the region. While the identification of this first hominin specimen from Haasgat is not unexpected given the composition of other South African penecontemporaneous site deposits, it represents one of the few

  7. Craniofacial biomechanics and functional and dietary inferences in hominin paleontology.

    PubMed

    Grine, Frederick E; Judex, Stefan; Daegling, David J; Ozcivici, Engin; Ungar, Peter S; Teaford, Mark F; Sponheimer, Matt; Scott, Jessica; Scott, Robert S; Walker, Alan

    2010-04-01

    Finite element analysis (FEA) is a potentially powerful tool by which the mechanical behaviors of different skeletal and dental designs can be investigated, and, as such, has become increasingly popular for biomechanical modeling and inferring the behavior of extinct organisms. However, the use of FEA to extrapolate from characterization of the mechanical environment to questions of trophic or ecological adaptation in a fossil taxon is both challenging and perilous. Here, we consider the problems and prospects of FEA applications in paleoanthropology, and provide a critical examination of one such study of the trophic adaptations of Australopithecus africanus. This particular FEA is evaluated with regard to 1) the nature of the A. africanus cranial composite, 2) model validation, 3) decisions made with respect to model parameters, 4) adequacy of data presentation, and 5) interpretation of the results. Each suggests that the results reflect methodological decisions as much as any underlying biological significance. Notwithstanding these issues, this model yields predictions that follow from the posited emphasis on premolar use by A. africanus. These predictions are tested with data from the paleontological record, including a phylogenetically-informed consideration of relative premolar size, and postcanine microwear fabrics and antemortem enamel chipping. In each instance, the data fail to conform to predictions from the model. This model thus serves to emphasize the need for caution in the application of FEA in paleoanthropological enquiry. Theoretical models can be instrumental in the construction of testable hypotheses; but ultimately, the studies that serve to test these hypotheses - rather than data from the models - should remain the source of information pertaining to hominin paleobiology and evolution. Copyright 2010 Elsevier Ltd. All rights reserved.

  8. Faunal change, environmental variability and late Pliocene hominin evolution.

    PubMed

    Bobe, René; Behrensmeyer, Anna K; Chapman, Ralph E

    2002-04-01

    Global change during the late Pliocene was manifested in declining temperatures, increased amplitude of climate cycles, and shifts in the periodicity of orbital climate forcing. Linking these changes to the evolution of African continental faunas and to hominin evolution requires well-documented fossil evidence that can be examined through substantial periods of time. The Omo sequence of southern Ethiopia provides such a database, and we use it to analyze change in the abundances of mammal taxa at different levels of temporal and taxonomic resolution between 4 and 2 Ma. This study provides new evidence for shifts through time in the ecological dominance of suids, cercopithecids, and bovids, and for a trend from more forested to more open woodland habitats. Superimposed on these long-term trends are two episodes of faunal change, one involving a marked shift in the abundances of different taxa at about 2.8+/-0.1 Ma, and the second the transition at 2.5 Ma from a 200-ka interval of faunal stability to marked variability over intervals of about 100 ka. The first appearance of Homo, the earliest artefacts, and the extinction of non-robust Australopithecus in the Omo sequence coincide in time with the beginning of this period of high variability. We conclude that climate change caused significant shifts in vegetation in the Omo paleo-ecosystem and is a plausible explanation for the gradual ecological change from forest to open woodland between 3.4 and 2.0 Ma, the faunal shift at 2.8 +/-0.1 Ma, and the change in the tempo of faunal variability of 2.5 Ma. Climate forcing in the late Pliocene is more clearly indicated by population shifts within the Omo mammal community than by marked turnover at the species level. Copyright 2002 Elsevier Science Ltd.

  9. Femoral neck structure and function in early hominins.

    PubMed

    Ruff, Christopher B; Higgins, Ryan

    2013-04-01

    All early (Pliocene-Early Pleistocene) hominins exhibit some differences in proximal femoral morphology from modern humans, including a long femoral neck and a low neck-shaft angle. In addition, australopiths (Au. afarensis, Au. africanus, Au. boisei, Paranthropus boisei), but not early Homo, have an "anteroposteriorly compressed" femoral neck and a small femoral head relative to femoral shaft breadth. Superoinferior asymmetry of cortical bone in the femoral neck has been claimed to be human-like in australopiths. In this study, we measured superior and inferior cortical thicknesses at the middle and base of the femoral neck using computed tomography in six Au. africanus and two P. robustus specimens. Cortical asymmetry in the fossils is closer overall to that of modern humans than to apes, although many values are intermediate between humans and apes, or even more ape-like in the midneck. Comparisons of external femoral neck and head dimensions were carried out for a more comprehensive sample of South and East African australopiths (n = 17) and two early Homo specimens. These show that compared with modern humans, femoral neck superoinferior, but not anteroposterior breadth, is larger relative to femoral head breadth in australopiths, but not in early Homo. Both internal and external characteristics of the australopith femoral neck indicate adaptation to relatively increased superoinferior bending loads, compared with both modern humans and early Homo. These observations, and a relatively small femoral head, are consistent with a slightly altered gait pattern in australopiths, involving more lateral deviation of the body center of mass over the stance limb.

  10. Molecular blood group typing in Banjar, Jawa, Mandailing and Kelantan Malays in Peninsular Malaysia.

    PubMed

    Abd Gani, Rahayu; Manaf, Siti Mariam; Zafarina, Zainuddin; Panneerchelvam, Sundararajulu; Chambers, Geoffrey Keith; Norazmi, Mohd Noor; Edinur, Hisham Atan

    2015-08-01

    In this study we genotyped ABO, Rhesus, Kell, Kidd and Duffy blood group loci in DNA samples from 120 unrelated individuals representing four Malay subethnic groups living in Peninsular Malaysia (Banjar: n = 30, Jawa: n = 30, Mandailing: n = 30 and Kelantan: n = 30). Analyses were performed using commercial polymerase chain reaction-sequence specific primer (PCR-SSP) typing kits (BAG Health Care GmbH, Lich, Germany). Overall, the present study has successfully compiled blood group datasets for the four Malay subethnic groups and used the datasets for studying ancestry and health.

  11. The Mystery of the Skulls: What Can Old Bones Tell Us about Hominin Evolution?

    ERIC Educational Resources Information Center

    Yerky, Mike Darwin; Wilczynski, Carolyn J.

    2014-01-01

    In this activity, students examine nine hominin skulls for specialized features and take measurements that will enable them to determine the relatedness of these species. They will ultimately place each specimen on a basic phylogenetic tree that also reveals the geological time frame in which each species lived. On the basis of their data, and…

  12. Geological and palaeontological context of a Pliocene juvenile hominin at Dikika, Ethiopia.

    PubMed

    Wynn, Jonathan G; Alemseged, Zeresenay; Bobe, René; Geraads, Denis; Reed, Denné; Roman, Diana C

    2006-09-21

    Since 1999, the Dikika Research Project (DRP; initiated by Z.A.) has conducted surveys and excavations in badlands that expose Pliocene and Pleistocene sediments south of the Awash River in Ethiopia, between surrounding hominin localities at Hadar, Gona and the Middle Awash region. Here we report our geological mapping and stratigraphic measurement of the DRP area, and the context of a remarkably well-preserved skeleton of the earliest known juvenile hominin at the Dikika DIK-1 locality. Our mapping of the DRP area permits a complete definition of the hominin-bearing Hadar Formation and provides a cohesive structural and tectonic framework defining its relationships to adjacent strata. Our findings reveal the basin-scale tectonic, depositional and palaeoenvironmental history of the area, as well as a clear taphonomic and palaeontological context for the juvenile hominin. Such data are crucial for understanding the environmental context of human evolution, and can be integrated into larger-scale tectonic and palaeoenvironmental studies. Our basin-scale approach to palaeoenvironments provides a means to elucidate the complex geological history occurring at the scale of temporally and geographically controlled fossil point localities, which occur within the rich tectonic and depositional history of the Awash Valley.

  13. Nuclear DNA sequences from the Middle Pleistocene Sima de los Huesos hominins.

    PubMed

    Meyer, Matthias; Arsuaga, Juan-Luis; de Filippo, Cesare; Nagel, Sarah; Aximu-Petri, Ayinuer; Nickel, Birgit; Martínez, Ignacio; Gracia, Ana; Bermúdez de Castro, José María; Carbonell, Eudald; Viola, Bence; Kelso, Janet; Prüfer, Kay; Pääbo, Svante

    2016-03-24

    A unique assemblage of 28 hominin individuals, found in Sima de los Huesos in the Sierra de Atapuerca in Spain, has recently been dated to approximately 430,000 years ago. An interesting question is how these Middle Pleistocene hominins were related to those who lived in the Late Pleistocene epoch, in particular to Neanderthals in western Eurasia and to Denisovans, a sister group of Neanderthals so far known only from southern Siberia. While the Sima de los Huesos hominins share some derived morphological features with Neanderthals, the mitochondrial genome retrieved from one individual from Sima de los Huesos is more closely related to the mitochondrial DNA of Denisovans than to that of Neanderthals. However, since the mitochondrial DNA does not reveal the full picture of relationships among populations, we have investigated DNA preservation in several individuals found at Sima de los Huesos. Here we recover nuclear DNA sequences from two specimens, which show that the Sima de los Huesos hominins were related to Neanderthals rather than to Denisovans, indicating that the population divergence between Neanderthals and Denisovans predates 430,000 years ago. A mitochondrial DNA recovered from one of the specimens shares the previously described relationship to Denisovan mitochondrial DNAs, suggesting, among other possibilities, that the mitochondrial DNA gene pool of Neanderthals turned over later in their history.

  14. Hominin cognitive evolution: identifying patterns and processes in the fossil and archaeological record

    PubMed Central

    Shultz, Susanne; Nelson, Emma; Dunbar, Robin I. M.

    2012-01-01

    As only limited insight into behaviour is available from the archaeological record, much of our understanding of historical changes in human cognition is restricted to identifying changes in brain size and architecture. Using both absolute and residual brain size estimates, we show that hominin brain evolution was likely to be the result of a mix of processes; punctuated changes at approximately 100 kya, 1 Mya and 1.8 Mya are supplemented by gradual within-lineage changes in Homo erectus and Homo sapiens sensu lato. While brain size increase in Homo in Africa is a gradual process, migration of hominins into Eurasia is associated with step changes at approximately 400 kya and approximately 100 kya. We then demonstrate that periods of rapid change in hominin brain size are not temporally associated with changes in environmental unpredictability or with long-term palaeoclimate trends. Thus, we argue that commonly used global sea level or Indian Ocean dust palaeoclimate records provide little evidence for either the variability selection or aridity hypotheses explaining changes in hominin brain size. Brain size change at approximately 100 kya is coincident with demographic change and the appearance of fully modern language. However, gaps remain in our understanding of the external pressures driving encephalization, which will only be filled by novel applications of the fossil, palaeoclimatic and archaeological records. PMID:22734056

  15. Hominins do not share a common postnatal facial ontogenetic shape trajectory.

    PubMed

    Cobb, S N; O'Higgins, P

    2004-05-15

    This paper examines the hypothesis raised by recent studies that postnatal trajectories of shape change in the facial skeleton are parallel between, at least, chimpanzees, modern humans and also fossil hominins, specifically australopithecines and possibly Neanderthals. In contrast, other studies point to divergences in postnatal shape trajectories within diverse groups of primates. As such there is some debate regarding the relative contributions of pre and postnatal ontogeny to adult morphological differences. This paper presents a series of geometric morphometric studies of the ontogeny of facial shape in hominins with the specific aim of resolving these issues. The results indicate that many differences in facial shape between hominins are established prenatally, however highly significant divergences of postnatal facial ontogeny are found among living hominins. Our studies point to possible differences between the shape ontogeny of the Australopithecus africanus face and that of African apes on the one hand and humans on the other. However, sampling experiments indicate that the small sample size of available specimens of A. africanus does not permit any conclusions to be drawn regarding comparative shape ontogeny of the face.

  16. Earliest Porotic Hyperostosis on a 1.5-Million-Year-Old Hominin, Olduvai Gorge, Tanzania

    PubMed Central

    Domínguez-Rodrigo, Manuel; Pickering, Travis Rayne; Diez-Martín, Fernando; Mabulla, Audax; Musiba, Charles; Trancho, Gonzalo; Baquedano, Enrique; Bunn, Henry T.; Barboni, Doris; Santonja, Manuel; Uribelarrea, David; Ashley, Gail M.; Martínez-Ávila, María del Sol; Barba, Rebeca; Gidna, Agness; Yravedra, José; Arriaza, Carmen

    2012-01-01

    Meat-eating was an important factor affecting early hominin brain expansion, social organization and geographic movement. Stone tool butchery marks on ungulate fossils in several African archaeological assemblages demonstrate a significant level of carnivory by Pleistocene hominins, but the discovery at Olduvai Gorge of a child's pathological cranial fragments indicates that some hominins probably experienced scarcity of animal foods during various stages of their life histories. The child's parietal fragments, excavated from 1.5-million-year-old sediments, show porotic hyperostosis, a pathology associated with anemia. Nutritional deficiencies, including anemia, are most common at weaning, when children lose passive immunity received through their mothers' milk. Our results suggest, alternatively, that (1) the developmentally disruptive potential of weaning reached far beyond sedentary Holocene food-producing societies and into the early Pleistocene, or that (2) a hominin mother's meat-deficient diet negatively altered the nutritional content of her breast milk to the extent that her nursing child ultimately died from malnourishment. Either way, this discovery highlights that by at least 1.5 million years ago early human physiology was already adapted to a diet that included the regular consumption of meat. PMID:23056303

  17. Sapropels and the age of hominins Omo I and II, Kibish, Ethiopia.

    PubMed

    McDougall, Ian; Brown, Francis H; Fleagle, John G

    2008-09-01

    The provenance and age of two Homo sapiens fossils (Omo I and Omo II) from the Kibish Formation in southern Ethiopia have been much debated. Here we confirm that Omo I and the somewhat more primitive-looking Omo II calvariae are from similar stratigraphic levels in Member I of the Kibish Formation. Based on (40)Ar/(39)Ar age measurements on alkali feldspar crystals from pumice clasts in the Nakaa'kire Tuff, a tuffaceous bed in Member I just below the hominin levels, we place an older limit of 198+/-14 ka (weighted mean age=196+/-2 ka) for the hominins. A younger limit of 104+/-7 ka (weighted mean age=104+/-1 ka) is provided by feldspars separated from pumice clasts in the Aliyo Tuff in Member III. Geological evidence indicates rapid deposition of each member of the Kibish Formation, concurrent with deposition of sapropels in the Mediterranean Sea. The (40)Ar/(39)Ar age measurements, together with correlations with sapropels, indicate that the hominin fossils are close in age to the older limit. Our preferred estimate of the age of the hominins is 195+/-5 ka, making them the earliest well-dated anatomically modern humans yet described.

  18. Dynamics of green Sahara periods and their role in hominin evolution.

    PubMed

    Larrasoaña, Juan C; Roberts, Andrew P; Rohling, Eelco J

    2013-01-01

    Astronomically forced insolation changes have driven monsoon dynamics and recurrent humid episodes in North Africa, resulting in green Sahara Periods (GSPs) with savannah expansion throughout most of the desert. Despite their potential for expanding the area of prime hominin habitats and favouring out-of-Africa dispersals, GSPs have not been incorporated into the narrative of hominin evolution due to poor knowledge of their timing, dynamics and landscape composition at evolutionary timescales. We present a compilation of continental and marine paleoenvironmental records from within and around North Africa, which enables identification of over 230 GSPs within the last 8 million years. By combining the main climatological determinants of woody cover in tropical Africa with paleoenvironmental and paleoclimatic data for representative (Holocene and Eemian) GSPs, we estimate precipitation regimes and habitat distributions during GSPs. Their chronology is consistent with the ages of Saharan archeological and fossil hominin sites. Each GSP took 2-3 kyr to develop, peaked over 4-8 kyr, biogeographically connected the African tropics to African and Eurasian mid latitudes, and ended within 2-3 kyr, which resulted in rapid habitat fragmentation. We argue that the well-dated succession of GSPs presented here may have played an important role in migration and evolution of hominins.

  19. Hominin cognitive evolution: identifying patterns and processes in the fossil and archaeological record.

    PubMed

    Shultz, Susanne; Nelson, Emma; Dunbar, Robin I M

    2012-08-05

    As only limited insight into behaviour is available from the archaeological record, much of our understanding of historical changes in human cognition is restricted to identifying changes in brain size and architecture. Using both absolute and residual brain size estimates, we show that hominin brain evolution was likely to be the result of a mix of processes; punctuated changes at approximately 100 kya, 1 Mya and 1.8 Mya are supplemented by gradual within-lineage changes in Homo erectus and Homo sapiens sensu lato. While brain size increase in Homo in Africa is a gradual process, migration of hominins into Eurasia is associated with step changes at approximately 400 kya and approximately 100 kya. We then demonstrate that periods of rapid change in hominin brain size are not temporally associated with changes in environmental unpredictability or with long-term palaeoclimate trends. Thus, we argue that commonly used global sea level or Indian Ocean dust palaeoclimate records provide little evidence for either the variability selection or aridity hypotheses explaining changes in hominin brain size. Brain size change at approximately 100 kya is coincident with demographic change and the appearance of fully modern language. However, gaps remain in our understanding of the external pressures driving encephalization, which will only be filled by novel applications of the fossil, palaeoclimatic and archaeological records.

  20. Surprising trunk rotational capabilities in chimpanzees and implications for bipedal walking proficiency in early hominins

    PubMed Central

    Thompson, Nathan E.; Demes, Brigitte; O'Neill, Matthew C.; Holowka, Nicholas B.; Larson, Susan G.

    2015-01-01

    Human walking entails coordinated out-of-phase axial rotations of the thorax and pelvis. A long-held assumption is that this ability relies on adaptations for trunk flexibility present in humans, but not in chimpanzees, other great apes, or australopithecines. Here we use three-dimensional kinematic analyses to show that, contrary to current thinking, chimpanzees walking bipedally rotate their lumbar and thoracic regions in a manner similar to humans. This occurs despite differences in the magnitude of trunk motion, and despite morphological differences in truncal ‘rigidity' between species. These results suggest that, like humans and chimpanzees, early hominins walked with upper body rotations that countered pelvic rotation. We demonstrate that even if early hominins walked with pelvic rotations 50% larger than humans, they may have accrued the energetic and mechanical benefits of out-of-phase thoracic rotations. This would have allowed early hominins to reduce work and locomotor cost, improving walking efficiency early in hominin evolution. PMID:26441046

  1. The Mystery of the Skulls: What Can Old Bones Tell Us about Hominin Evolution?

    ERIC Educational Resources Information Center

    Yerky, Mike Darwin; Wilczynski, Carolyn J.

    2014-01-01

    In this activity, students examine nine hominin skulls for specialized features and take measurements that will enable them to determine the relatedness of these species. They will ultimately place each specimen on a basic phylogenetic tree that also reveals the geological time frame in which each species lived. On the basis of their data, and…

  2. Wild chimpanzee dentition and its implications for assessing life history in immature hominin fossils

    PubMed Central

    Zihlman, Adrienne; Bolter, Debra; Boesch, Christophe

    2004-01-01

    Data from three African field sites on Pan troglodytes demonstrate an unambiguous pattern of a slower growth rate in wild vs. captive chimpanzee populations. A revised dental growth chronology for chimpanzees is similar to estimated timing of Homo erectus and therefore has implications for interpreting life history in hominins. PMID:15243156

  3. Dental microwear and diet of the Plio-Pleistocene hominin Paranthropus boisei.

    PubMed

    Ungar, Peter S; Grine, Frederick E; Teaford, Mark F

    2008-04-30

    The Plio-Pleistocene hominin Paranthropus boisei had enormous, flat, thickly enameled cheek teeth, a robust cranium and mandible, and inferred massive, powerful chewing muscles. This specialized morphology, which earned P. boisei the nickname "Nutcracker Man", suggests that this hominin could have consumed very mechanically challenging foods. It has been recently argued, however, that specialized hominin morphology may indicate adaptations for the consumption of occasional fallback foods rather than preferred resources. Dental microwear offers a potential means by which to test this hypothesis in that it reflects actual use rather than genetic adaptation. High microwear surface texture complexity and anisotropy in extant primates can be associated with the consumption of exceptionally hard and tough foods respectively. Here we present the first quantitative analysis of dental microwear for P. boisei. Seven specimens examined preserved unobscured antemortem molar microwear. These all show relatively low complexity and anisotropy values. This suggests that none of the individuals consumed especially hard or tough foods in the days before they died. The apparent discrepancy between microwear and functional anatomy is consistent with the idea that P. boisei presents a hominin example of Liem's Paradox, wherein a highly derived morphology need not reflect a specialized diet.

  4. Fossil hominin shoulders support an African ape-like last common ancestor of humans and chimpanzees.

    PubMed

    Young, Nathan M; Capellini, Terence D; Roach, Neil T; Alemseged, Zeresenay

    2015-09-22

    Reconstructing the behavioral shifts that drove hominin evolution requires knowledge of the timing, magnitude, and direction of anatomical changes over the past ∼6-7 million years. These reconstructions depend on assumptions regarding the morphotype of the Homo-Pan last common ancestor (LCA). However, there is little consensus for the LCA, with proposed models ranging from African ape to orangutan or generalized Miocene ape-like. The ancestral state of the shoulder is of particular interest because it is functionally associated with important behavioral shifts in hominins, such as reduced arboreality, high-speed throwing, and tool use. However, previous morphometric analyses of both living and fossil taxa have yielded contradictory results. Here, we generated a 3D morphospace of ape and human scapular shape to plot evolutionary trajectories, predict ancestral morphologies, and directly test alternative evolutionary hypotheses using the hominin fossil evidence. We show that the most parsimonious model for the evolution of hominin shoulder shape starts with an African ape-like ancestral state. We propose that the shoulder evolved gradually along a single morphocline, achieving modern human-like configuration and function within the genus Homo. These data are consistent with a slow, progressive loss of arboreality and increased tool use throughout human evolution.

  5. Fossil hominin shoulders support an African ape-like last common ancestor of humans and chimpanzees

    PubMed Central

    Young, Nathan M.; Capellini, Terence D.; Roach, Neil T.; Alemseged, Zeresenay

    2015-01-01

    Reconstructing the behavioral shifts that drove hominin evolution requires knowledge of the timing, magnitude, and direction of anatomical changes over the past ∼6–7 million years. These reconstructions depend on assumptions regarding the morphotype of the Homo–Pan last common ancestor (LCA). However, there is little consensus for the LCA, with proposed models ranging from African ape to orangutan or generalized Miocene ape-like. The ancestral state of the shoulder is of particular interest because it is functionally associated with important behavioral shifts in hominins, such as reduced arboreality, high-speed throwing, and tool use. However, previous morphometric analyses of both living and fossil taxa have yielded contradictory results. Here, we generated a 3D morphospace of ape and human scapular shape to plot evolutionary trajectories, predict ancestral morphologies, and directly test alternative evolutionary hypotheses using the hominin fossil evidence. We show that the most parsimonious model for the evolution of hominin shoulder shape starts with an African ape-like ancestral state. We propose that the shoulder evolved gradually along a single morphocline, achieving modern human-like configuration and function within the genus Homo. These data are consistent with a slow, progressive loss of arboreality and increased tool use throughout human evolution. PMID:26351685

  6. Dental Microwear and Diet of the Plio-Pleistocene Hominin Paranthropus boisei

    PubMed Central

    Ungar, Peter S.; Grine, Frederick E.; Teaford, Mark F.

    2008-01-01

    The Plio-Pleistocene hominin Paranthropus boisei had enormous, flat, thickly enameled cheek teeth, a robust cranium and mandible, and inferred massive, powerful chewing muscles. This specialized morphology, which earned P. boisei the nickname “Nutcracker Man”, suggests that this hominin could have consumed very mechanically challenging foods. It has been recently argued, however, that specialized hominin morphology may indicate adaptations for the consumption of occasional fallback foods rather than preferred resources. Dental microwear offers a potential means by which to test this hypothesis in that it reflects actual use rather than genetic adaptation. High microwear surface texture complexity and anisotropy in extant primates can be associated with the consumption of exceptionally hard and tough foods respectively. Here we present the first quantitative analysis of dental microwear for P. boisei. Seven specimens examined preserved unobscured antemortem molar microwear. These all show relatively low complexity and anisotropy values. This suggests that none of the individuals consumed especially hard or tough foods in the days before they died. The apparent discrepancy between microwear and functional anatomy is consistent with the idea that P. boisei presents a hominin example of Liem's Paradox, wherein a highly derived morphology need not reflect a specialized diet. PMID:18446200

  7. Dynamics of Green Sahara Periods and Their Role in Hominin Evolution

    PubMed Central

    Larrasoaña, Juan C.; Roberts, Andrew P.; Rohling, Eelco J.

    2013-01-01

    Astronomically forced insolation changes have driven monsoon dynamics and recurrent humid episodes in North Africa, resulting in green Sahara Periods (GSPs) with savannah expansion throughout most of the desert. Despite their potential for expanding the area of prime hominin habitats and favouring out-of-Africa dispersals, GSPs have not been incorporated into the narrative of hominin evolution due to poor knowledge of their timing, dynamics and landscape composition at evolutionary timescales. We present a compilation of continental and marine paleoenvironmental records from within and around North Africa, which enables identification of over 230 GSPs within the last 8 million years. By combining the main climatological determinants of woody cover in tropical Africa with paleoenvironmental and paleoclimatic data for representative (Holocene and Eemian) GSPs, we estimate precipitation regimes and habitat distributions during GSPs. Their chronology is consistent with the ages of Saharan archeological and fossil hominin sites. Each GSP took 2–3 kyr to develop, peaked over 4–8 kyr, biogeographically connected the African tropics to African and Eurasian mid latitudes, and ended within 2–3 kyr, which resulted in rapid habitat fragmentation. We argue that the well-dated succession of GSPs presented here may have played an important role in migration and evolution of hominins. PMID:24146882

  8. Investigating the Signature of Aquatic Resource Use within Pleistocene Hominin Dietary Adaptations

    PubMed Central

    Archer, Will; Braun, David R.

    2013-01-01

    There is general agreement that the diet of early hominins underwent dramatic changes shortly after the appearance of stone tools in the archaeological record. It is often assumed that this change is associated with dietary expansion to incorporate large mammal resources. Although other aspects of the hominin diet, such as aquatic or vegetal resources, are assumed to be a part of hominin subsistence, identifying evidence of these adaptations has proved difficult. Here we present a series of analyses that provide methodological support for the inclusion of aquatic resources in hominin dietary reconstructions. We suggest that bone surface modifications in aquatic species are morphologically distinguishable from bone surface modifications on terrestrial taxa. We relate these findings to differences that we document in the surface mechanical properties of the two types of bone, as reflected by significant differences in bone surface microhardness values between aquatic and terrestrial species. We hypothesize that the characteristics of bone surface modifications on aquatic taxa inhibit the ability of zooarchaeologists to consistently diagnose them correctly. Contingently, this difficulty influences correspondence levels between zooarchaeologists, and may therefore result in misinterpretation of the taphonomic history of early Pleistocene aquatic faunal assemblages. A blind test using aquatic specimens and a select group of 9 experienced zooarchaeologists as participants was designed to test this hypothesis. Investigation of 4 different possible explanations for blind test results suggest the dominant factors explaining patterning relate to (1) the specific methodologies employed to diagnose modifications on aquatic specimens and (2) the relative experience of participants with modifications on aquatic bone surfaces. Consequently we argue that an important component of early hominin diets may have hitherto been overlooked as a result of (a) the paucity of referential

  9. A simple rule governs the evolution and development of hominin tooth size.

    PubMed

    Evans, Alistair R; Daly, E Susanne; Catlett, Kierstin K; Paul, Kathleen S; King, Stephen J; Skinner, Matthew M; Nesse, Hans P; Hublin, Jean-Jacques; Townsend, Grant C; Schwartz, Gary T; Jernvall, Jukka

    2016-02-25

    The variation in molar tooth size in humans and our closest relatives (hominins) has strongly influenced our view of human evolution. The reduction in overall size and disproportionate decrease in third molar size have been noted for over a century, and have been attributed to reduced selection for large dentitions owing to changes in diet or the acquisition of cooking. The systematic pattern of size variation along the tooth row has been described as a 'morphogenetic gradient' in mammal, and more specifically hominin, teeth since Butler and Dahlberg. However, the underlying controls of tooth size have not been well understood, with hypotheses ranging from morphogenetic fields to the clone theory. In this study we address the following question: are there rules that govern how hominin tooth size evolves? Here we propose that the inhibitory cascade, an activator-inhibitor mechanism that affects relative tooth size in mammals, produces the default pattern of tooth sizes for all lower primary postcanine teeth (deciduous premolars and permanent molars) in hominins. This configuration is also equivalent to a morphogenetic gradient, finally pointing to a mechanism that can generate this gradient. The pattern of tooth size remains constant with absolute size in australopiths (including Ardipithecus, Australopithecus and Paranthropus). However, in species of Homo, including modern humans, there is a tight link between tooth proportions and absolute size such that a single developmental parameter can explain both the relative and absolute sizes of primary postcanine teeth. On the basis of the relationship of inhibitory cascade patterning with size, we can use the size at one tooth position to predict the sizes of the remaining four primary postcanine teeth in the row for hominins. Our study provides a development-based expectation to examine the evolution of the unique proportions of human teeth.

  10. A geometric morphometric analysis of hominin lower molars: Evolutionary implications and overview of postcanine dental variation.

    PubMed

    Gómez-Robles, Aida; Bermúdez de Castro, José María; Martinón-Torres, María; Prado-Simón, Leyre; Arsuaga, Juan Luis

    2015-05-01

    Lower molars have been extensively studied in the context of hominin evolution using classic and geometric morphometric analyses, 2D and 3D approaches, evaluations of the external (outer enamel surface) and internal anatomy (dentine, pulp chamber, and radicular canals), and studies of the crown and root variation. In this study, we present a 2D geometric morphometric analysis of the crown anatomy of lower first, second, and third molars of a broad sample of hominins, including Pliocene and Lower, Middle, and Upper Pleistocene species coming from Africa, Asia, and Europe. We show that shape variability increases from first to second and third molars. While first molars tend to retain a relatively stable 5-cusped conformation throughout the hominin fossil record, second and third molars show marked distal reductions in later Homo species. This trend to distal reduction is similar to that observed in previous studies of premolars and upper second and third molars, and points to a correlated reduction of distal areas across the whole postcanine dentition. Results on lower molar variation, as well as on other postcanine teeth, show certain trends in European Pleistocene populations from the Atapuerca sites. Middle Pleistocene hominins from Sima de los Huesos show Neanderthal affinities and strong dental reduction, especially in the most distal molars. The degree of dental reduction in this population is stronger than that observed in classic Neanderthals. Homo antecessor hominins from Gran Dolina-TD6 have primitive lower teeth that contrast with their more derived upper teeth. The evolutionary implications of these dental affinities are discussed in light of recent paleogenetic studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Investigating the signature of aquatic resource use within Pleistocene hominin dietary adaptations.

    PubMed

    Archer, Will; Braun, David R

    2013-01-01

    There is general agreement that the diet of early hominins underwent dramatic changes shortly after the appearance of stone tools in the archaeological record. It is often assumed that this change is associated with dietary expansion to incorporate large mammal resources. Although other aspects of the hominin diet, such as aquatic or vegetal resources, are assumed to be a part of hominin subsistence, identifying evidence of these adaptations has proved difficult. Here we present a series of analyses that provide methodological support for the inclusion of aquatic resources in hominin dietary reconstructions. We suggest that bone surface modifications in aquatic species are morphologically distinguishable from bone surface modifications on terrestrial taxa. We relate these findings to differences that we document in the surface mechanical properties of the two types of bone, as reflected by significant differences in bone surface microhardness values between aquatic and terrestrial species. We hypothesize that the characteristics of bone surface modifications on aquatic taxa inhibit the ability of zooarchaeologists to consistently diagnose them correctly. Contingently, this difficulty influences correspondence levels between zooarchaeologists, and may therefore result in misinterpretation of the taphonomic history of early Pleistocene aquatic faunal assemblages. A blind test using aquatic specimens and a select group of 9 experienced zooarchaeologists as participants was designed to test this hypothesis. Investigation of 4 different possible explanations for blind test results suggest the dominant factors explaining patterning relate to (1) the specific methodologies employed to diagnose modifications on aquatic specimens and (2) the relative experience of participants with modifications on aquatic bone surfaces. Consequently we argue that an important component of early hominin diets may have hitherto been overlooked as a result of (a) the paucity of referential

  12. Land conversion and economic development in Jawa Barat Province: Trade off or Synergy?

    NASA Astrophysics Data System (ADS)

    Nuryartono, N.; Tongato, A.; Yusdiyanto, S.; Pasaribu, S. H.; Anggraenie, T.

    2017-01-01

    Jawa Barat province contributed 22 percent to the national rice production. Since land availability is one of important factors for food production, this must be addressed seriously. During the period of 2008-2013, there had been a shrinking of wetland area of 20,502 hectares (nearly 2.2 percent out of total wetland area in Jawa Barat). This condition may have implications on local and national food production and food security. This study analyzes influencing factors for land use changes of wetland in West Java using a panel of 5200 villages’ level data in 2011-2014 by panel method. Important influencing factors that contribute to the land conversions mostly related to the development such as increasing number of new settlements and regional economic development. Spatially, using GIS map shows some areas have high rate of land conversion compared to other areas. The highest land conversion was in Kabupaten Bogor followed by Kabupaten Bekasi, while lowest was Bogor city. As there are tradeoff between economic development and land use, government policy should be addressed for economic development while it should be simultaneously preventing wetland conversion.

  13. Late Miocene Molluscan Stage of Jawa Insight from New Field Studies

    NASA Astrophysics Data System (ADS)

    Aswan; Sufiati, Elina; Kistiani, Desty; Yudi Abdurrahman, Irman; Dwijo Santoso, Wahyu; Rudyawan, Alfend; Zin Oo, Thaw

    2017-06-01

    Neogene stratigraphic stages of Jawa based on molluscan index fossils firstly compiled by Oostingh in 1938. This concept is widely used by palaeontologists, both for application in and outside Jawa. Based on the estimated ages of previous researchers the Neogene stages from old to young are: Rembangian stage considered equivalent to Early Miocene, Preangerian stage (Middle Miocene), Odengian stage (Upper Miocene), Cheribonian stage (Early Pliocene), Sondian stage (Late Pliocene) and Bantamian stage (Early Pleistocene). Further studies to determine a more precise age of each stage are often difficult due to lack of planktonic foraminifera fossils and other age index fossils within the sedimentary deposits that are mostly shallow marine sediments. This study focuses to re-examine the age of sediments of Preangerian and Odengian Stages on new field studies. The type locality and rock units that are correlated with these stages are part of the well-exposed Nyalindung formation around Sukabumi area. The studies were carried out in four main fosill-rich sedimentary sequences that are exposed along Cijarian, Citalahab, Ciangsana and Ciodeng rivers. More detailed ages were obtained from the sediments. The exposed sequences along the Ciangsana and Citalahab rivers are Middle Miocene (N9-N14) while the Cijarian and Ciodeng rivers sequences were deposited between Middle to early Late Miocene (N9-N16). The Nyalindung formation in the Cijarian river also contain Vicarya sp, an index fossil that marks a rise in sea level in the Miocene (12 Ma), which previously only been reported from the Ciangsana river sediments.

  14. Early human settlements in the southern Qinling Mountains, central China

    NASA Astrophysics Data System (ADS)

    Sun, Xuefeng; Lu, Huayu; Wang, Shejiang; Yi, Liang; Li, Yongxiang; Bahain, Jean Jacques; Voinchet, Pierre; Hu, Xuzhi; Zeng, Lin; Zhang, Wenchao; Zhuo, Haixin

    2017-05-01

    China is a key area of early human settlement in East Asia, with numerous Paleolithic localities indicating an early Pleistocene presence of hominins in northern and southern China. Considerable research has been devoted to determining possible migration routes for hominins linking the two areas. In this paper, we report the discovery of several loess-covered Paleolithic sites in the Hanzhong and Ankang Basins along the Hanjiang River in the southern piedmont of the Qinling Mountains (QLM) in central China. A chronology is developed for these sections using a combination of detailed optically stimulated luminescence dating, magnetostratigraphic analyses, and pedostratigraphic correlation with the well-dated loess-paleosol sequence of the central Chinese Loess Plateau. The results indicate that the age of the oldest lithic assemblage at the Longgangsi locality 3 Paleolithic site in Hanzhong Basin is ∼1.20 Ma, thus making this locality as one of the oldest sites in central China. Our work also indicates that hominins occupied the Hanjiang valley at several times: ∼1.2, 0.9, ∼0.6, and ∼0.1 Ma. We propose that the Hanjiang River Valley was a probable hominin routeway through the QLM because many sites corresponding to these different phases were also discovered to the north of the QLM. Future study on the Hanjiang River Valley is important for verifying the hypothesis of an early human migration route between southern and northern China.

  15. Dating Trinil: towards establishing an age framework for the hominin-bearing deposits at the Homo erectus site Trinil (Indonesia)

    NASA Astrophysics Data System (ADS)

    Joordens, Josephine; Adhityatama, Shinatria; Yurnaldi, Dida; Reimann, Tony; Rahayu Ekowati, Dian; Huffman, Frank; Barianto, Didit; Sutisna, Indra; Pop, Eduard; Alink, Gerrit; Kuiper, Klaudia; Priyatno, Hadi; Simanjuntak, Truman; Verpoorte, Alexander

    2017-04-01

    In the 1890s, the anatomist Eugène Dubois found the first fossils of our extinct relative Homo erectus at Trinil on Java (Indonesia). Since then, one of the major questions of humankind has been to find out "what made us human". H. erectus was morphologically in many ways like us, and the first hominin species to spread, from about 1.8 Ma onwards, over Africa, Eurasia and Southeast Asia. However, it is still unknown what behavioural and lifestyle characteristics allowed H. erectus to achieve this cosmopolitan distribution, and reach the island of Java at 1.5 Ma. Dating of Javanese hominin sites is notoriously difficult, yet crucial to resolve the climatic-environmental backdrop and biogeography of hominin species in the region. At present, there is still a lack of well-constrained ages for the important hominin-bearing Hauptknochenschicht (HK) at Trinil. Moreover, the fossiliferous layers above the HK have not been dated at all. Also, there is a paucity of climatic-environmental data on the HK and overlying layers. This hampers the reconstruction of a climatic-environmental framework with temporal correlations to hominin fossils from Trinil, and placement Trinil layers in the context of Asian hominin biogeography. Here, we report on our pilot fieldwork at Trinil in August 2016, as part of an ongoing collaborative project of the ARKENAS Jakarta (Indonesia) and the Faculty of Archaeology, Leiden University (The Netherlands). We have collected geochronological sediment samples from a number of carefully measured and described stratigraphic sections covering the HK and overlying layers, for the application of three dating methods (OSL, Ar/Ar, paleomagnetism). The aim is to provide a first reliable age model for the hominin-bearing and other fossiliferous layers at Trinil. We will present preliminary fieldwork results and discuss the implications for dispersal of fauna (including hominins).

  16. Megadontia, striae periodicity and patterns of enamel secretion in Plio-Pleistocene fossil hominins.

    PubMed

    Lacruz, Rodrigo S; Dean, M Christopher; Ramirez-Rozzi, Fernando; Bromage, Timothy G

    2008-08-01

    Early hominins formed large and thick-enamelled cheek-teeth within relatively short growth periods as compared with modern humans. To understand better the developmental basis of this process, we measured daily enamel increments, or cross striations, in 17 molars of Plio-Pleistocene hominins representing seven different species, including specimens attributed to early Homo. Our results show considerable variation across species, although all specimens conformed to the known pattern characterised by greater values in outer than inner enamel, and greater cuspal than cervical values. We then compared our results with the megadontia index, which represents tooth size in relation to body mass, for each species to assess the effect of daily growth rates on tooth size. Our results indicate that larger toothed (megadont) taxa display higher rates or faster forming enamel than smaller toothed hominins. By forming enamel quickly, large tooth crowns were able to develop within the constraints of shorter growth periods. Besides daily increments, many animals express long-period markings (striae of Retzius) in their enamel. We report periodicity values (number of cross striations between adjacent striae) in 14 new specimens of Australopithecus afarensis, Paranthropus aethiopicus, Paranthropus boisei, Homo habilis, Homo rudolfensis and Homo erectus, and show that long-period striae express a strong association with male and average male-female body mass. Our results for Plio-Pleistocene hominins show that the biological rhythms that give rise to long-period striae are encompassed within the range of variation known for modern humans, but show a lower mean and modal value of 7 days in australopithecines. In our sample of early Homo, mean and modal periodicity values were 8 days, and therefore similar to modern humans. These new data on daily rates of enamel formation and periodicity provide a better framework to interpret surface manifestations of internal growth markings on

  17. Leaf wax biomarker reconstruction of Early Pleistocene hydrological variation during hominin evolution in West Turkana, Kenya

    NASA Astrophysics Data System (ADS)

    Lupien, R.; Russell, J. M.; Cohen, A. S.; Feibel, C. S.; Beck, C.; Castañeda, I. S.

    2016-12-01

    Climate change is thought to play a critical role in human evolution; however, this hypothesis is difficult to test due to a lack of long, high-quality paleoclimate records from key hominin fossil locales. To address this issue, we examine Plio-Pleistocene lake sediment drill cores from East Africa that were recovered by the Hominin Sites and Paleolakes Drilling Project, an international effort to study the environment in which our hominin ancestors evolved and dispersed. With new data we test various evolutionary hypotheses, such as the "variability selection" hypothesis, which posits that high-frequency environmental variations selected for generalist traits that allowed hominins to expand into variable environments. We analyzed organic geochemical signals of climate in lake cores from West Turkana, Kenya, which span 1.87-1.38 Ma and contain the first fossils from Homo erectus. In particular, we present a compound-specific hydrogen isotopic analysis of terrestrial plant waxes (δDwax) that records regional hydrology. The amount effect dominates water isotope fractionation in the tropics; therefore, these data are interpreted to reflect mean annual rainfall, which affects vegetation structure and thus, hominin habitats. The canonical view of East Africa is that climate became drier and increasingly felt high-latitude glacial-interglacial cycles during the Plio-Pleistocene. However, the drying trend seen in some records is not evident in Turkana δDwax, signifying instead a climate with a steady mean state. Spectral and moving variance analyses indicate paleohydrological variations related to both high-latitude glaciation (41 ky cycle) and local insolation-forced monsoons (21 ky cycle). An interval of particularly high-amplitude rainfall variation occurs at 1.7 Ma, which coincides with the intensification of the Walker Circulation. These results identify high- and low-latitude controls on East African paleohydrology during Homo erectus evolution. In particular, the

  18. Influence of Plio-Pleistocene basin hydrology on the Turkana hominin enamel carbonate δ(18)O values.

    PubMed

    Quinn, Rhonda L

    2015-09-01

    Stable oxygen isotopes of hominin enamel carbonate (δ(18)OEC) provide a window into aspects of past drinking behavior and diet, body size, breastfeeding and weaning, mobility, and paleoclimate. It is tempting to compare all hominins across time and space in order to gauge species-level adaptations to changing environments and niche separation between those living sympatrically. Basinal, sub-basinal, and micro-environmental differences, however, may exert an influence on variation in enamel carbonate isotopic values that must be reconciled before hominin species across Africa can be meaningfully compared. Plio-Pleistocene Turkana hominin δ(18)OEC values show a considerable spread, potentially revealing many intrinsic and extrinsic contributing factors operating on different scales. In this study, I examine Turkana hominin δ(18)OEC values relative to identity (taxon, tooth type and number, body size of taxon), dietary (δ(13)C value, Turkana coeval and modern mammalian δ(18)OEC values), and contextual (time, depositional environment) information of each specimen and collection locality and discuss various potential influences. Turkana hominin δ(18)OEC values may primarily reflect differences in imbibed water sources (lake vs. river) as a function of evolving basin hydrology. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Western Palaearctic palaeoenvironmental conditions during the Early and early Middle Pleistocene inferred from large mammal communities, and implications for hominin dispersal in Europe

    NASA Astrophysics Data System (ADS)

    Kahlke, Ralf-Dietrich; García, Nuria; Kostopoulos, Dimitris S.; Lacombat, Frédéric; Lister, Adrian M.; Mazza, Paul P. A.; Spassov, Nikolai; Titov, Vadim V.

    2011-06-01

    -Western and North-Western Europe on the other. This trend was due to the effect of the Atlantic Ocean, while in Southern Europe the relatively low continentality was balanced by influences from the Mediterranean Sea. When plotted against evidence of hominin occurrence, the data on western Palaearctic habitat diversity inferred from large mammal communities indicate clear environmental stimuli for the earliest human dispersal in Europe. These are: (1) a wide range of habitats, implying a high diversity of resources; (2) mild climates with low seasonality, implying a lack of strong environmental fluctuations. Around 1.8 Ma at the latest, hominins of African origin entered the western Palaearctic for the first time, taking advantage of the diversity of habitats and resources, particularly along large river systems. Their subsequent westward spread between 1.7 and 1.3 Ma was restricted to Mediterranean-influenced areas, which offered a high variability of habitats and relatively low seasonality. The increase in environmental diversity, which occurred from 1.2 Ma onwards, opened up South-Eastern and Eastern Europe for hominin occupation. According to the available records, North-Western and Central Europe were initially colonized during late Early to early Middle Pleistocene interglacials, when these regions experienced periods of low seasonality and considerable habitat diversity.

  20. Developmental response to cold stress in cranial morphology of Rattus: implications for the interpretation of climatic adaptation in fossil hominins

    PubMed Central

    Rae, Todd C; Viðarsdóttir, Una Strand; Jeffery, Nathan; Steegmann, A. Theodore

    2006-01-01

    Adaptation to climate occupies a central position in biological anthropology. The demonstrable relationship between temperature and morphology in extant primates (including humans) forms the basis of the interpretation of the Pleistocene hominin Homo neanderthalensis as a cold-adapted species. There are contradictory signals, however, in the pattern of primate craniofacial changes associated with climatic conditions. To determine the direction and extent of craniofacial change associated with temperature, and to understand the proximate mechanisms underlying cold adaptations in vertebrates in general, dry crania from previous experiments on cold- and warm-reared rats were investigated using computed tomography scanning and three-dimensional digitization of cranial landmarks. Aspects of internal and external cranial morphology were compared using standard statistical and geometric morphometric techniques. The results suggest that the developmental response to cold stress produces subtle but significant changes in facial shape, and a relative decrease in the volume of the maxillary sinuses (and nasal cavity), both of which are independent of the size of the skull or postcranium. These changes are consistent with comparative studies of temperate climate primates, but contradict previous interpretations of cranial morphology of Pleistocene Hominini. PMID:17002945

  1. Desert agricultural terrace systems at EBA Jawa (Jordan) - Layout, water availability and efficiency

    NASA Astrophysics Data System (ADS)

    Meister, Julia; Krause, Jan; Müller-Neuhof, Bernd; Portillo, Marta; Reimann, Tony; Schütt, Brigitta

    2016-04-01

    Located in the arid basalt desert of northeastern Jordan, the Early Bronze Age (EBA) settlement of Jawa is by far the largest and best preserved archaeological EBA site in the region. Recent surveys in the close vicinity revealed well-preserved remains of three abandoned agricultural terrace systems. In the presented study these archaeological features are documented by detailed mapping and the analysis of the sediment records in a multi-proxy approach. To study the chronology of the terrace systems optically stimulated luminescence (OSL) is used. In order to evaluate the efficiency of the water management techniques and its impact on harvest yields, a crop simulation model (CropSyst) under today's climatic conditions is applied, simulating crop yields with and without (runoff) irrigation. In order to do so, a runoff time series for each agricultural terrace system and its catchment is generated, applying the SCS runoff curve number method (CN) based on rainfall and soil data. Covering a total area of 38 ha, irrigated terrace agriculture was practiced on slopes, small plateaus, and valleys in the close vicinity of Jawa. Floodwater from nearby wadis or runoff from adjacent slopes was collected and diverted via surface canals. The terraced fields were arranged in cascades, allowing effective water exploitation through a system of risers, canals and spillways. The examined terrace profiles show similar stratigraphic sequences of mixed unstratified fine sediments that are composed of small-scale relocated sediments with local origin. The accumulation of these fines is associated with the construction of agricultural terraces, forcing infiltration and storage of the water within the terraces. Two OSL ages of terrace fills indicate that the construction of these terrace systems started as early as 5300 ± 300 a, which fits well to the beginning of the occupation phase of Jawa at around 3.500 calBC, thus making them to the oldest examples of its kind in the Middle East

  2. Genetic history of an archaic hominin group from Denisova Cave in Siberia

    PubMed Central

    Reich, David; Green, Richard E.; Kircher, Martin; Krause, Johannes; Patterson, Nick; Durand, Eric Y.; Viola, Bence; Briggs, Adrian W.; Stenzel, Udo; Johnson, Philip L. F.; Maricic, Tomislav; Good, Jeffrey M.; Marques-Bonet, Tomas; Alkan, Can; Fu, Qiaomei; Mallick, Swapan; Li, Heng; Meyer, Matthias; Eichler, Evan E.; Stoneking, Mark; Richards, Michael; Talamo, Sahra; Shunkov, Michael V.; Derevianko, Anatoli P.; Hublin, Jean-Jacques; Kelso, Janet; Slatkin, Montgomery; Pääbo, Svante

    2015-01-01

    Using DNA extracted from a finger bone found in Denisova Cave in southern Siberia, we have sequenced the genome of an archaic hominin to about 1.9-fold coverage. This individual is from a group that shares a common origin with Neanderthals. This population was not involved in the putative gene flow from Neanderthals into Eurasians; however, the data suggest that it contributed 4–6% of its genetic material to the genomes of present-day Melanesians. We designate this hominin population ‘Denisovans’ and suggest that it may have been widespread in Asia during the Late Pleistocene epoch. A tooth found in Denisova Cave carries a mitochondrial genome highly similar to that of the finger bone. This tooth shares no derived morphological features with Neanderthals or modern humans, further indicating that Denisovans have an evolutionary history distinct from Neanderthals and modern humans. PMID:21179161

  3. Disentangling hominin and carnivore activities near a spring at FLK North (Olduvai Gorge, Tanzania)

    NASA Astrophysics Data System (ADS)

    Domínguez-Rodrigo, M.; Mabulla, A. Z. P.; Bunn, H. T.; Diez-Martin, F.; Baquedano, E.; Barboni, D.; Barba, R.; Domínguez-Solera, S.; Sánchez, P.; Ashley, G. M.; Yravedra, J.

    2010-11-01

    FLK North is one of the densest concentrations of fossils found in Olduvai Gorge. A recent taphonomic re-evaluation of the collection excavated by Leakey at the site suggests that it was a palimpsest in which most of the animals were accumulated and modified by carnivores. The lithic tools therefore seem to have an independent depositional history from most of the fauna. The present study, based on new excavations, expands the evidence supporting this interpretation and demonstrates a thicker deposit than was reported by Leakey, including new archaeological levels. It also shows that in the few instances where hominins butchered carcasses, meat, not marrow, was their main target. This argues against passive scavenging hypotheses, which emphasize the dietary role of marrow, and instead underscores the importance of meat in the diet of early Pleistocene hominins.

  4. Chimpanzee fauna isotopes provide new interpretations of fossil ape and hominin ecologies.

    PubMed

    Nelson, Sherry V

    2013-12-22

    Carbon and oxygen stable isotopes within modern and fossil tooth enamel record the aspects of an animal's diet and habitat use. This investigation reports the first isotopic analyses of enamel from a large chimpanzee community and associated fauna, thus providing a means of comparing fossil ape and early hominin palaeoecologies with those of a modern ape. Within Kibale National Park forest, oxygen isotopes differentiate primate niches, allowing for the first isotopic reconstructions of degree of frugivory versus folivory as well as use of arboreal versus terrestrial resources. In a comparison of modern and fossil community isotopic profiles, results indicate that Sivapithecus, a Miocene ape from Pakistan, fed in the forest canopy, as do chimpanzees, but inhabited a forest with less continuous canopy or fed more on leaves. Ardipithecus, an early hominin from Ethiopia, fed both arboreally and terrestrially in a more open habitat than inhabited by chimpanzees.

  5. Morphological affinities of Homo naledi with other Plio-Pleistocene hominins: a phenetic approach.

    PubMed

    Neves, Walter A; Bernardo, Danilo V; Pantaleoni, Ivan

    2017-07-24

    Recent fossil material found in Dinaledi Chamber, South Africa, was initially described as a new species of genus Homo, namely Homo naledi. The original study of this new material has pointed to a close proximity with Homo erectus. More recent investigations have, to some extent, confirmed this assignment. Here we present a phenetic analysis based on dentocranial metric variables through Principal Components Analysis and Cluster Analysis based on these fossils and other Plio-Pleistocene hominins. Our results concur that the Dinaledi fossil hominins pertain to genus Homo. However, in our case, their nearest neighbors are Homo habilis and Australopithecus sediba. We suggest that Homo naledi is in fact a South African version of Homo habilis, and not a new species. This can also be applied to Australopithecus sediba.

  6. Chimpanzee fauna isotopes provide new interpretations of fossil ape and hominin ecologies

    PubMed Central

    Nelson, Sherry V.

    2013-01-01

    Carbon and oxygen stable isotopes within modern and fossil tooth enamel record the aspects of an animal's diet and habitat use. This investigation reports the first isotopic analyses of enamel from a large chimpanzee community and associated fauna, thus providing a means of comparing fossil ape and early hominin palaeoecologies with those of a modern ape. Within Kibale National Park forest, oxygen isotopes differentiate primate niches, allowing for the first isotopic reconstructions of degree of frugivory versus folivory as well as use of arboreal versus terrestrial resources. In a comparison of modern and fossil community isotopic profiles, results indicate that Sivapithecus, a Miocene ape from Pakistan, fed in the forest canopy, as do chimpanzees, but inhabited a forest with less continuous canopy or fed more on leaves. Ardipithecus, an early hominin from Ethiopia, fed both arboreally and terrestrially in a more open habitat than inhabited by chimpanzees. PMID:24197413

  7. Australopithecus anamensis: a finite-element approach to studying the functional adaptations of extinct hominins.

    PubMed

    Macho, Gabriele A; Shimizu, Daisuke; Jiang, Yong; Spears, Iain R

    2005-04-01

    Australopithecus anamensis is the stem species of all later hominins and exhibits the suite of characters traditionally associated with hominins, i.e., bipedal locomotion when on the ground, canine reduction, and thick-enameled teeth. The functional consequences of its thick enamel are, however, unclear. Without appropriate structural reinforcement, these thick-enameled teeth may be prone to failure. This article investigates the mechanical behavior of A. anamensis enamel and represents the first in a series that will attempt to determine the functional adaptations of hominin teeth. First, the microstructural arrangement of enamel prisms in A. anamensis teeth was reconstructed using recently developed software and was compared with that of extant hominoids. Second, a finite-element model of a block of enamel containing one cycle of prism deviation was reconstructed for Homo, Pan, Gorilla, and A. anamensis and the behavior of these tissues under compressive stress was determined. Despite similarities in enamel microstructure between A. anamensis and the African great apes, the structural arrangement of prismatic enamel in A. anamensis appears to be more effective in load dissipation under these compressive loads. The findings may imply that this hominin species was well adapted to puncture crushing and are in some respects contrary to expectations based on macromorphology of teeth. Taking together, information obtained from both finite-element analyses and dental macroanatomy leads us to suggest that A. anamensis was probably adapted for habitually consuming a hard-tough diet. However, additional tests are needed to understand the functional adaptations of A. anamensis teeth fully.

  8. Taxonomic identification of Lower Pleistocene fossil hominins based on distal humeral diaphyseal cross-sectional shape

    PubMed Central

    2015-01-01

    The coexistence of multiple hominin species during the Lower Pleistocene has long presented a challenge for taxonomic attribution of isolated postcrania. Although fossil humeri are well-suited for studies of hominin postcranial variation due to their relative abundance, humeral articular morphology has thus far been of limited value for differentiating Paranthropus from Homo. On the other hand, distal humeral diaphyseal shape has been used to justify such generic distinctions at Swartkrans. The potential utility of humeral diaphyseal shape merits larger-scale quantitative analysis, particularly as it permits the inclusion of fragmentary specimens lacking articular morphology. This study analyzes shape variation of the distal humeral diaphysis among fossil hominins (c. 2-1 Ma) to test the hypothesis that specimens can be divided into distinct morphotypes. Coordinate landmarks were placed on 3D laser scans to quantify cross-sectional shape at a standardized location of the humeral diaphysis (proximal to the olecranon fossa) for a variety of fossil hominins and extant hominids. The fossil sample includes specimens attributed to species based on associated craniodental remains. Mantel tests of matrix correlation were used to assess hypotheses about morphometric relationships among the fossils by comparing empirically-derived Procrustes distance matrices to hypothetical model matrices. Diaphyseal shape variation is consistent with the hypothesis of three distinct morphotypes (Paranthropus, Homo erectus, non-erectus early Homo) in both eastern and southern Africa during the observed time period. Specimens attributed to non-erectus early Homo are unique among hominids with respect to the degree of relative anteroposterior flattening, while H. erectus humeri exhibit morphology more similar to that of modern humans. In both geographic regions, Paranthropus is characterized by a morphology that is intermediate with respect to those morphological features that differentiate

  9. Environmental change and hominin exploitation of C4-based resources in wetland/savanna mosaics.

    PubMed

    Stewart, Kathlyn M

    2014-12-01

    Eastern and southern Africa experienced ongoing climatic and tectonic instability in the Plio-Pleistocene, alongside declining forests and expanding grasslands. Most known hominin genera (Australopithecus spp., Kenyanthropus, Paranthropus spp., Homo spp.) appear roughly between 4.2 and 1.8 Ma (millions of years ago). Explanations for these speciation events have focused on adaptations to environmental change, particularly in terrestrial biomes. However, the links between environmental change and hominin adaptations have not always been clear. Often overlooked is that Plio-Pleistocene vegetation included not just terrestrial environments, but a large component of edaphic (wet) C4 grasses and sedges. In this paper it is suggested that in response to environmental fluctuations, hominins engaged in conservative long-term ecological and dietary patterns, based on predictable C4/C3 wetland and terrestrial resources. Data are presented from six hominin locales, which demonstrate reliance on plant-based resources (sedges, grasses, and other vegetation) in C4-inclusive wetland/savanna mosaics. After roughly 2.4 Ma, severe climate variability is associated with early Homo and perhaps Paranthropus boisei broadening their diet to familiar but less preferred foods: vertebrates and invertebrates. These foods consistently provided early Homo with essential nutrients, which reduced selection pressures and allowed for increases in brain size. After 1.65 Ma, a 20% increase in the C4 dietary component of Homo occurs alongside increased relative brain size. P. boisei also increases its C4 dietary component by 15% after 1.65 Ma. These increases imply that both taxa continued to broaden their diet within the C4-based wetlands/savanna biome, with Homo putting a greater emphasis on mammals.

  10. Body mass estimates of hominin fossils and the evolution of human body size.

    PubMed

    Grabowski, Mark; Hatala, Kevin G; Jungers, William L; Richmond, Brian G

    2015-08-01

    Body size directly influences an animal's place in the natural world, including its energy requirements, home range size, relative brain size, locomotion, diet, life history, and behavior. Thus, an understanding of the biology of extinct organisms, including species in our own lineage, requires accurate estimates of body size. Since the last major review of hominin body size based on postcranial morphology over 20 years ago, new fossils have been discovered, species attributions have been clarified, and methods improved. Here, we present the most comprehensive and thoroughly vetted set of individual fossil hominin body mass predictions to date, and estimation equations based on a large (n = 220) sample of modern humans of known body masses. We also present species averages based exclusively on fossils with reliable taxonomic attributions, estimates of species averages by sex, and a metric for levels of sexual dimorphism. Finally, we identify individual traits that appear to be the most reliable for mass estimation for each fossil species, for use when only one measurement is available for a fossil. Our results show that many early hominins were generally smaller-bodied than previously thought, an outcome likely due to larger estimates in previous studies resulting from the use of large-bodied modern human reference samples. Current evidence indicates that modern human-like large size first appeared by at least 3-3.5 Ma in some Australopithecus afarensis individuals. Our results challenge an evolutionary model arguing that body size increased from Australopithecus to early Homo. Instead, we show that there is no reliable evidence that the body size of non-erectus early Homo differed from that of australopiths, and confirm that Homo erectus evolved larger average body size than earlier hominins. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Ischial Form as an Indicator of Bipedal Kinematics in Early Hominins: A Test Using Extant Anthropoids.

    PubMed

    Lewton, Kristi L; Scott, Jeremiah E

    2017-05-01

    Human ischia contrast with those of great apes in being craniocaudally short and dorsally projecting. This configuration is thought to facilitate greater hip extension in humans during bipedal locomotion. This link has been used to infer kinematics in early hominins, but the consequences of variation in ischial configuration for gait remain uncertain. Kinematic data for a limited sample of extant nonhuman primates demonstrate that there is variation in hip extension in these taxa during bipedal behaviors-specifically, Hylobates and Ateles are capable of greater extension than Pan and Macaca. In this study, we tested the hypothesis that ischial length and orientation are functionally linked with hip extension during bipedalism among these taxa. As expected, humans have the shortest ischia, followed by gibbons, spider monkeys, chimpanzees, and macaques. Our predictions for ischial orientation are not supported, however: macaques, gibbons, and spider monkeys do not vary in this trait, and they have ischia that are less dorsally angled than that of the chimpanzee. The results for ischium length provide limited support for the idea that the early hominin Ardipithecus ramidus, with its long, caudally oriented ischium was not capable of humanlike extended-hip bipedalism, and that the ischial shortening observed in post-Ardipithecus hominins reflects a shift toward a more humanlike gait. In contrast, while our results do not necessarily refute a link between ischial orientation and hip extension in hominins, they do not provide comparative support, making changes in ischial orientation in this part of the fossil record more difficult to interpret. Anat Rec, 300:845-858, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  12. Palaeoenvironmental evolution at Plio-Pleistocene Hominin sites in Western Kenya: Preliminary results

    NASA Astrophysics Data System (ADS)

    Vincent, Thomas; Whitfield, Elizabeth; Bishop, Laura; Plummer, Thomas; Ditchfield, Peter; Blumenthal, Scott; Finestone, Emma; Kiriakoulakis, Kostas

    2017-04-01

    This research uses a multiproxy approach to create detailed reconstructions of Plio-Pleistocene hominin landscapes and environments on the Homa Peninsula, western Kenya. Sedimentary sequences associated with this time period, containing hominin archaeological traces and faunal remains, are studied using analyses of particle size, phytoliths and lipid biomarkers. Reconstructing the palaeoenvironmental substrate here is critical in developing an understanding of the activity and behaviour of previous hominin inhabitants. Three archaeological sites exist in the region that form the bases of this research; these include Kanjera South, Nyayanga and Sare River. Research at Kanjera began in the early 20th century, but systematic investigation of the artefact and faunal assemblages of the southern exposures (Kanjera South), dating to ca. 2 Ma, did not begin until 1995. Field investigations and isotopic analyses of palaeosol carbonate nodules and fauna suggested that Kanjera South sediments were deposited in alluvial and lake marginal environments, on a grassy plain between wooded slopes and a permanent water body. Nyayanga and Sare River are new sites which have been little studied until present. Sediments at Nyayanga are thought to be ca. 2.6 Ma, whilst those at Sare River are ca. 1.77 Ma in age. This research refines previous reconstructions of the depositional environment at Kanjera South using analyses of particle size and end member mixing. These suggest that deposition occurred mainly through low-energy, ephemeral flows in a marginal lacustrine environment, with high energy, hyper-concentrated and viscous flows occurring intermittently. In contrast, these same techniques and field investigations at Nyayanga suggest there was a more consistent energy regime here than at Kanjera South, with sediments being deposited under low-energy conditions. Sediment samples at Sare River are undergoing similar analyses. Through detailed analyses of sediments at three archaeological

  13. Chimpanzee isotopic ecology: a closed canopy C3 template for hominin dietary reconstruction.

    PubMed

    Carlson, Bryce A; Kingston, John D

    2014-11-01

    The most significant hominin adaptations, including features used to distinguish and/or classify taxa, are critically tied to the dietary environment. Stable isotopic analyses of tooth enamel from hominin fossils have provided intriguing evidence for significant C4/CAM (crassulacean acid metabolism) resource consumption in a number of Plio-Pleistocene hominin taxa. Relating isotopic tooth signatures to specific dietary items or proportions of C3 versus C4/CAM plants, however, remains difficult as there is an ongoing need to document and quantify isotopic variability in modern ecosystems. This study investigates the ecological variables responsible for carbon isotopic discrimination and variability within the C3-dominated dietary niche of a closed canopy East African hominoid, Pan troglodytes, from Ngogo, Kibale National Park, Uganda. δ(13)C values among C3 resources utilized by Ngogo chimpanzees were highly variable, ranging over 13‰. Infrequent foraging on papyrus (the only C4 plant consumed by chimpanzees at the site) further extended this isotopic range. Variation was ultimately most attributable to mode of photosynthesis (C3 versus C4), food type, and elevation, which together accounted for approximately 78% of the total sample variation. Among C3 food types, bulk carbon values ranged from -24.2‰ to -31.1‰ with intra-plant variability up to 12.1‰. Pith and sapling leaves were statistically more (13)C depleted than pulp, seeds, flowers, cambium, roots, leaf buds, and leaves from mature trees. The effect of elevation on carbon variation was highly significant and equivalent to an approximately 1‰ increase in δ(13)C for every 150 m of elevation gain, likely reflecting habitat variability associated with topography. These results indicate significant δ(13)C variation attributable to food type and elevation among C3 resources and provide important data for hominin dietary interpretations based on carbon isotopic analyses. Copyright © 2014 Elsevier Ltd

  14. Dental microwear texture analysis shows within-species diet variability in fossil hominins.

    PubMed

    Scott, Robert S; Ungar, Peter S; Bergstrom, Torbjorn S; Brown, Christopher A; Grine, Frederick E; Teaford, Mark F; Walker, Alan

    2005-08-04

    Reconstructing the diets of extinct hominins is essential to understanding the paleobiology and evolutionary history of our lineage. Dental microwear, the study of microscopic tooth-wear resulting from use, provides direct evidence of what an individual ate in the past. Unfortunately, established methods of studying microwear are plagued with low repeatability and high observer error. Here we apply an objective, repeatable approach for studying three-dimensional microwear surface texture to extinct South African hominins. Scanning confocal microscopy together with scale-sensitive fractal analysis are used to characterize the complexity and anisotropy of microwear. Results for living primates show that this approach can distinguish among diets characterized by different fracture properties. When applied to hominins, microwear texture analysis indicates that Australopithecus africanus microwear is more anisotropic, but also more variable in anisotropy than Paranthropus robustus. This latter species has more complex microwear textures, but is also more variable in complexity than A. africanus. This suggests that A. africanus ate more tough foods and P. robustus consumed more hard and brittle items, but that both had variable and overlapping diets.

  15. An Early Pleistocene hominin mandible from Atapuerca-TD6, Spain

    PubMed Central

    Carbonell, E.; Bermúdez de Castro, J. M.; Arsuaga, J. L.; Allue, E.; Bastir, M.; Benito, A.; Cáceres, I.; Canals, T.; Díez, J. C.; van der Made, J.; Mosquera, M.; Ollé, A.; Pérez-González, A.; Rodríguez, J.; Rodríguez, X. P.; Rosas, A.; Rosell, J.; Sala, R.; Vallverdú, J.; Vergés, J. M.

    2005-01-01

    We present a mandible recovered in 2003 from the Aurora Stratum of the TD6 level of the Gran Dolina site (Sierra de Atapuerca, northern Spain). The specimen, catalogued as ATD6-96, adds to the hominin sample recovered from this site in 1994–1996, and assigned to Homo antecessor. ATD6-96 is the left half of a gracile mandible belonging to a probably female adult individual with premolars and molars in place. This mandible shows a primitive structural pattern shared with all African and Asian Homo species. However, it is small and exhibits a remarkable gracility, a trait shared only with the Early and Middle Pleistocene Chinese hominins. Furthermore, none of the mandibular features considered apomorphic in the European Middle and Early Upper Pleistocene hominin lineage are present in ATD6-96. This evidence reinforces the taxonomic identity of H. antecessor and is consistent with the hypothesis of a close relationship between this species and Homo sapiens. PMID:15824320

  16. Could plant extracts have enabled hominins to acquire honey before the control of fire?

    PubMed

    Kraft, Thomas S; Venkataraman, Vivek V

    2015-08-01

    Honey is increasingly recognized as an important food item in human evolution, but it remains unclear whether extinct hominins could have overcome the formidable collective stinging defenses of honey bees during honey acquisition. The utility of smoke for this purpose is widely recognized, but little research has explored alternative methods of sting deterrence such as the use of plant secondary compounds. To consider whether hominins could have used plant extracts as a precursor or alternative to smoke, we review the ethnographic, ethnobotanical, and plant chemical ecology literature to examine how humans use plants in combination with, and independently of, smoke during honey collection. Plant secondary compounds are diverse in their physiological and behavioral effects on bees and differ fundamentally from those of smoke. Plants containing these chemicals are widespread and prove to be remarkably effective in facilitating honey collection by honey hunters and beekeepers worldwide. While smoke may be superior as a deterrent to bees, plant extracts represent a plausible precursor or alternative to the use of smoke during honey collection by hominins. Smoke is a sufficient but not necessary condition for acquiring honey in amounts exceeding those typically obtained by chimpanzees, suggesting that significant honey consumption could have predated the control of fire.

  17. Adaptation to hard-object feeding in sea otters and hominins.

    PubMed

    Constantino, Paul J; Lee, James J-W; Morris, Dylan; Lucas, Peter W; Hartstone-Rose, Adam; Lee, Wah-Keat; Dominy, Nathaniel J; Cunningham, Andrew; Wagner, Mark; Lawn, Brian R

    2011-07-01

    The large, bunodont postcanine teeth in living sea otters (Enhydra lutris) have been likened to those of certain fossil hominins, particularly the 'robust' australopiths (genus Paranthropus). We examine this evolutionary convergence by conducting fracture experiments on extracted molar teeth of sea otters and modern humans (Homo sapiens) to determine how load-bearing capacity relates to tooth morphology and enamel material properties. In situ optical microscopy and x-ray imaging during simulated occlusal loading reveal the nature of the fracture patterns. Explicit fracture relations are used to analyze the data and to extrapolate the results from humans to earlier hominins. It is shown that the molar teeth of sea otters have considerably thinner enamel than those of humans, making sea otter molars more susceptible to certain kinds of fractures. At the same time, the base diameter of sea otter first molars is larger, diminishing the fracture susceptibility in a compensatory manner. We also conduct nanoindentation tests to map out elastic modulus and hardness of sea otter and human molars through a section thickness, and microindentation tests to measure toughness. We find that while sea otter enamel is just as stiff elastically as human enamel, it is a little softer and tougher. The role of these material factors in the capacity of dentition to resist fracture and deformation is considered. From such comparisons, we argue that early hominin species like Paranthropus most likely consumed hard food objects with substantially higher biting forces than those exerted by modern humans. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. The role of character displacement in the molarization of hominin mandibular premolars.

    PubMed

    Schroer, Kes; Wood, Bernard

    2015-06-01

    Closely related species are likely to experience resource competition in areas where their ranges overlap. Fossil evidence suggests that hominins in East Africa c. 2-1.5 million years ago may have lived synchronically and sympatrically, and that competition may have contributed to the different tooth sizes observed in Homo and Paranthropus. To assess the likelihood that these taxa overlapped, we applied a character displacement model to the postcanine tooth size of fossil hominins and validated this model in populations of living primates. Mandibular fourth premolar (P4 ) crown size was measured from fossil taxa and from living primate species where dietary overlap is established. Dimensions of the P4 crown were fitted to a character matrix and described as the response variables of a generalized linear model that took taxon and location as input variables. The model recovered significant divergence in samples of closely related, living primates. When applied to fossil hominins the same model detected strong indications of character displacement between early Homo and Paranthropus (P = 0.002) on the basis of their P4 crown size. Our study is an example of how ecologically informed morphologies measured in appropriate extant referents can provide a comparative context for assessing community and ecological evolution in the fossil record. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  19. Dental microwear texture analysis of hominins recovered by the Olduvai Landscape Paleoanthropology Project, 1995-2007.

    PubMed

    Ungar, Peter S; Krueger, Kristin L; Blumenschine, Robert J; Njau, Jackson; Scott, Robert S

    2012-08-01

    Dental microwear analysis has proven to be a valuable tool for the reconstruction of aspects of diet in early hominins. That said, sample sizes for some groups are small, decreasing our confidence that results are representative of a given taxon and making it difficult to assess within-species variation. Here we present microwear texture data for several new specimens of Homo habilis and Paranthropus boisei from Olduvai Gorge, bringing sample sizes for these species in line with those published for most other early hominins. These data are added to those published to date, and microwear textures of the enlarged sample of H. habilis (n = 10) and P. boisei (n = 9) are compared with one another and with those of other early hominins. New results confirm that P. boisei does not have microwear patterns expected of a hard-object specialist. Further, the separate texture complexity analyses of early Homo species suggest that Homo erectus ate a broader range of foods, at least in terms of hardness, than did H. habilis, P. boisei, or the "gracile" australopiths studied. Finally, differences in scale of maximum complexity and perhaps textural fill volume between H. habilis and H. erectus are noted, suggesting further possible differences between these species in diet.

  20. Isotopic evidence for an early shift to C4 resources by Pliocene hominins in Chad

    PubMed Central

    Lee-Thorp, Julia; Likius, Andossa; Mackaye, Hassane T.; Vignaud, Patrick; Sponheimer, Matt; Brunet, Michel

    2012-01-01

    Foods derived from C4 plants were important in the dietary ecology of early Pleistocene hominins in southern and eastern Africa, but the origins and geographic variability of this relationship remain unknown. Carbon isotope data show that Australopithecus bahrelghazali individuals from Koro Toro in Chad are significantly enriched in 13C, indicating a dependence on C4 resources. As these sites are over 3 million years in age, the results extend the pattern of C4 dependence seen in Paranthropus boisei in East Africa by more than 1.5 million years. The Koro Toro hominin fossils were found in argillaceous sandstone levels along with abundant grazing and aquatic faunal elements that, in combination, indicate the presence of open to wooded grasslands and stream channels associated with a greatly enlarged Lake Chad. In such an environment, the most abundant C4 plant resources available to A. bahrelghazali were grasses and sedges, neither of which is usually considered as standard great ape fare. The results suggest an early and fundamental shift in hominin dietary ecology that facilitated the exploitation of new habitats. PMID:23150583

  1. Stable isotopes in fossil hominin tooth enamel suggest a fundamental dietary shift in the Pliocene.

    PubMed

    Lee-Thorp, Julia A; Sponheimer, Matt; Passey, Benjamin H; de Ruiter, Darryl J; Cerling, Thure E

    2010-10-27

    Accumulating isotopic evidence from fossil hominin tooth enamel has provided unexpected insights into early hominin dietary ecology. Among the South African australopiths, these data demonstrate significant contributions to the diet of carbon originally fixed by C(4) photosynthesis, consisting of C(4) tropical/savannah grasses and certain sedges, and/or animals eating C(4) foods. Moreover, high-resolution analysis of tooth enamel reveals strong intra-tooth variability in many cases, suggesting seasonal-scale dietary shifts. This pattern is quite unlike that seen in any great apes, even 'savannah' chimpanzees. The overall proportions of C(4) input persisted for well over a million years, even while environments shifted from relatively closed (ca 3 Ma) to open conditions after ca 1.8 Ma. Data from East Africa suggest a more extreme scenario, where results for Paranthropus boisei indicate a diet dominated (approx. 80%) by C(4) plants, in spite of indications from their powerful 'nutcracker' morphology for diets of hard objects. We argue that such evidence for engagement with C(4) food resources may mark a fundamental transition in the evolution of hominin lineages, and that the pattern had antecedents prior to the emergence of Australopithecus africanus. Since new isotopic evidence from Aramis suggests that it was not present in Ardipithecus ramidus at 4.4 Ma, we suggest that the origins lie in the period between 3 and 4 Myr ago.

  2. Avoidance of overheating and selection for both hair loss and bipedality in hominins.

    PubMed

    Ruxton, Graeme D; Wilkinson, David M

    2011-12-27

    Two frequently debated aspects of hominin evolution are the development of upright bipedal stance and reduction in body hair. It has long been argued, on the basis of heat-balance models, that thermoregulation might have been important in the evolution of both of these traits. Previous models were based on a stationary individual standing in direct sunlight; here we extend this approach to consider a walking hominin, having argued that walking is more thermally challenging than remaining still. Further, stationary activities may be more compatible with shade seeking than activities (such as foraging) involving travel across the landscape. Our model predictions suggest that upright stance probably evolved for nonthermoregulatory reasons. However, the thermoregulatory explanation for hair loss was supported. Specifically, we postulate progressive hair loss being selected and this allowing individuals to be active in hot, open environments initially around dusk and dawn without overheating. Then, as our ancestors' hair loss increased and sweating ability improved over evolutionary time, the fraction of the day when they could remain active in such environments extended. Our model suggests that only when hair loss and sweating ability reach near-modern human levels could hominins have been active in the heat of the day in hot, open environments.

  3. New dating evidence of the early presence of hominins in Southern Europe.

    PubMed

    Michel, Véronique; Shen, Chuan-Chou; Woodhead, Jon; Hu, Hsun-Ming; Wu, Chung-Che; Moullé, Pierre-Élie; Khatib, Samir; Cauche, Dominique; Moncel, Marie-Hélène; Valensi, Patricia; Chou, Yu-Min; Gallet, Sylvain; Echassoux, Anna; Orange, François; de Lumley, Henry

    2017-08-30

    The first "Out of Africa" migrations represent a seminal event in the history of humankind. At the gates of Europe, the first appearance of Hominins is recorded in Georgia, 1.8 million years ago (Ma); however, the picture of migration across the continent remains incomplete. Vallonnet Cave (France) is a Lower Paleolithic prehistoric site with traces of hominin activities including lithic remains and cut-marks on mammal bones. Here, we apply the uranium-lead (U-Pb) methods to two flowstones to date the intervening archaeological levels. The U-Pb data, coupled with paleomagnetic constraints, provide an age range from 1.2 to 1.1 Ma. The results conclusively demonstrate that Vallonnet Cave is one of the oldest European prehistoric sites in France with early hominin occupations associated with an Epivillafranchian fauna. Combined with data from other archaeological sites, the new precise chronology suggests a widespread occupation the Northern Mediterranean to Southwestern Europe at ~1.2 Ma.

  4. Stable isotopes in fossil hominin tooth enamel suggest a fundamental dietary shift in the Pliocene

    PubMed Central

    Lee-Thorp, Julia A.; Sponheimer, Matt; Passey, Benjamin H.; de Ruiter, Darryl J.; Cerling, Thure E.

    2010-01-01

    Accumulating isotopic evidence from fossil hominin tooth enamel has provided unexpected insights into early hominin dietary ecology. Among the South African australopiths, these data demonstrate significant contributions to the diet of carbon originally fixed by C4 photosynthesis, consisting of C4 tropical/savannah grasses and certain sedges, and/or animals eating C4 foods. Moreover, high-resolution analysis of tooth enamel reveals strong intra-tooth variability in many cases, suggesting seasonal-scale dietary shifts. This pattern is quite unlike that seen in any great apes, even ‘savannah’ chimpanzees. The overall proportions of C4 input persisted for well over a million years, even while environments shifted from relatively closed (ca 3 Ma) to open conditions after ca 1.8 Ma. Data from East Africa suggest a more extreme scenario, where results for Paranthropus boisei indicate a diet dominated (approx. 80%) by C4 plants, in spite of indications from their powerful ‘nutcracker’ morphology for diets of hard objects. We argue that such evidence for engagement with C4 food resources may mark a fundamental transition in the evolution of hominin lineages, and that the pattern had antecedents prior to the emergence of Australopithecus africanus. Since new isotopic evidence from Aramis suggests that it was not present in Ardipithecus ramidus at 4.4 Ma, we suggest that the origins lie in the period between 3 and 4 Myr ago. PMID:20855312

  5. Conclusions: implications of the Liang Bua excavations for hominin evolution and biogeography.

    PubMed

    Morwood, M J; Jungers, W L

    2009-11-01

    Excavations at Liang Bua, on the Indonesian island of Flores, have yielded a stratified sequence of stone artifacts and faunal remains spanning the last 95k.yr., which includes the skeletal remains of two human species, Homo sapiens in the Holocene and Homo floresiensis in the Pleistocene. This paper summarizes and focuses on some of the evidence for Homo floresiensis in context, as presented in this Special Issue edition of the Journal of Human Evolution and elsewhere. Attempts to dismiss the Pleistocene hominins (and the type specimen LB1 in particular) as pathological pygmy humans are not compatible with detailed analyses of the skull, teeth, brain endocast, and postcranium. We initially concluded that H. floresiensis may have evolved by insular dwarfing of a larger-bodied hominin species over 880k.yr. or more. However, recovery of additional specimens and the numerous primitive morphological traits seen throughout the skeleton suggest instead that it is more likely to be a late representative of a small-bodied lineage that exited Africa before the emergence of Homo erectus sensu lato. Homo floresiensis is clearly not an australopithecine, but does retain many aspects of anatomy (and perhaps behavior) that are probably plesiomorphic for the genus Homo. We also discuss some of the other implications of this tiny, endemic species for early hominin dispersal and evolution (e.g., for the "Out of Africa 1" paradigm and more specifically for colonizing Southeast Asia), and we present options for future research in the region.

  6. Isotopic evidence for an early shift to C₄ resources by Pliocene hominins in Chad.

    PubMed

    Lee-Thorp, Julia; Likius, Andossa; Mackaye, Hassane T; Vignaud, Patrick; Sponheimer, Matt; Brunet, Michel

    2012-12-11

    Foods derived from C(4) plants were important in the dietary ecology of early Pleistocene hominins in southern and eastern Africa, but the origins and geographic variability of this relationship remain unknown. Carbon isotope data show that Australopithecus bahrelghazali individuals from Koro Toro in Chad are significantly enriched in (13)C, indicating a dependence on C(4) resources. As these sites are over 3 million years in age, the results extend the pattern of C(4) dependence seen in Paranthropus boisei in East Africa by more than 1.5 million years. The Koro Toro hominin fossils were found in argillaceous sandstone levels along with abundant grazing and aquatic faunal elements that, in combination, indicate the presence of open to wooded grasslands and stream channels associated with a greatly enlarged Lake Chad. In such an environment, the most abundant C(4) plant resources available to A. bahrelghazali were grasses and sedges, neither of which is usually considered as standard great ape fare. The results suggest an early and fundamental shift in hominin dietary ecology that facilitated the exploitation of new habitats.

  7. Early and Middle Pleistocene Faunal and hominins dispersals through Southwestern Asia

    NASA Astrophysics Data System (ADS)

    Bar-Yosef, Ofer; Belmaker, Miriam

    2011-06-01

    This review summarizes the paleoecology of the Early and Middle Pleistocene of southwestern Asia, based on both flora and fauna, retrieved from a series of 'windows' provided by the excavated sites. The incomplete chrono-stratigraphy of this vast region does not allow to accept the direct chronological correlation between the available sites and events of faunal and hominin dispersals from Africa. It also demonstrates that hominins survived in a mixed landscape of open parkland with forested surrounding hills. In addition, the prevailing environmental conditions are not sufficient to explain successful adaptations to new ecological niches away from the African savanna of the bearers of 'core and flake' and the Acheulian industries, The differences in knapping and secondary shaping of stone artifacts probably reflect the learned traditions of different groups of hominins. The current distribution of lithic industries across Eurasia is undoubtedly incomplete due to lack of cultural continuities as well as paucity of field research in several sub-regions. This observation supports the contention that what we view as a constant stream of migrants was actually interrupted many times. The continuous occupation of southwestern Asia by the makers of the Acheulian is in contrast with neighboring regions such as the Iranian plateau and Eastern Europe. A more complex model is required to explain the recorded Eurasian archaeological-cultural mosaic.

  8. Hominin-carnivore interactions during the Chinese Early Paleolithic: taphonomic perspectives from Xujiayao.

    PubMed

    Norton, Christopher J; Gao, Xing

    2008-07-01

    The ability of archaic Homo sapiens to survive in more northerly latitudes was contingent on securing a regular source of animal fat and protein. We present a taphonomic study that examines how successful these hominins were at acquiring these food sources during the latter part of the Early Paleolithic in Northeast Asia. This study focuses on the long bone midshaft surface modifications observed on the faunal remains from Xujiayao, a middle-late Pleistocene open-air site located at 40 degrees latitude in the western Nihewan Basin, northern China. The faunal assemblage is dominated by equid remains. Analysis of the percussion, tooth, and cut mark frequencies on the long bone midshafts demonstrates that the Xujiayao hominins had primary access to high utility (meat-bearing and marrow-rich) long bones. Investigation of the dual-patterned (tooth-marked and butchery-marked) bone fragments suggests that hominins were under little pressure from competing carnivores to abandon their kills. The lack of significant differences between the size of fragments with only percussion-marks and those with only tooth-marks supports these findings. Fragmentation ratios indicate that forelimbs were more intensively processed than hind limbs. Based on the water rounding and abrasion data, the Xujiayao assemblage is likely of autochthonous origin. Since the age of Xujiayao is still in question, we can only conclude that archaic Homo sapiens were successful predators of large game in Northeast Asia some time during the latter part of the Early Paleolithic.

  9. Age estimation in fossil hominins: comparing dental development in early Homo with modern humans.

    PubMed

    Dean, M Christopher; Liversidge, Helen M

    2015-01-01

    Previous studies have used molar tooth eruption as a comparative marker of maturation in early fossil hominins. However, tooth eruption and tooth formation are independent maturational processes. To determine whether estimates of age for entering a stage of dental development in three early hominin fossils fell within the distribution of a modern human sample. This study used a comparative model of dental development to identify the stages of dental development most likely to provide information about length of the growth period in early fossil hominins. Age estimates for stages of dental development in fossils were superimposed onto a normal distribution of the same radiographically defined stages derived from a sample of 6540 children of diverse geographical origin. Both within the dentition of S7-37, from Sangiran, Java, but also for stages of two other specimens (KNM-WT 15000 from Kenya and StW 151 from South Africa), all age estimates for later stages of tooth formation fell within the modern sample range. A pattern appears to exist in early Homo where, both within and between developing dentitions, age estimates for stages of P4, M2 and M3 tooth formation fell consistently among the more advanced individuals of the modern human sample.

  10. The Hadropithecus conundrum reconsidered, with implications for interpreting diet in fossil hominins

    PubMed Central

    Dumont, Elizabeth R.; Ryan, Timothy M.; Godfrey, Laurie R.

    2011-01-01

    The fossil ‘monkey lemur’ Hadropithecus stenognathus has long excited palaeontologists because its skull bears an astonishing resemblance to those of robust australopiths, an enigmatic side branch of the human family tree. Multiple lines of evidence point to the likelihood that these australopiths ate at least some ‘hard’, stress-limited food items, but conflicting data from H. stenognathus pose a conundrum. While its hominin-like craniofacial architecture is suggestive of an ability to generate high bite forces, details of its tooth structure suggest that it was not well equipped to withstand the forces imposed by cracking hard objects. Here, we use three-dimensional digital reconstructions and finite-element analysis to test the hard-object processing hypothesis. We show that Archaeolemur sp. cf. A. edwardsi, a longer-faced close relative of H. stenognathus that lacked hominin convergences, was probably capable of breaking apart large, stress-limited food items, while Hadropithecus was better suited to processing small, displacement-limited (tougher but more compliant) foods. Our suggestion that H. stenognathus was not a hard-object feeder has bearing on the interpretation of hominin cranial architecture; the features shared by H. stenognathus and robust australopiths do not necessarily reflect adaptations for hard-object processing. PMID:21525060

  11. Ardipithecus ramidus and the evolution of language and singing: An early origin for hominin vocal capability.

    PubMed

    Clark, Gary; Henneberg, Maciej

    2017-03-01

    In this paper we analyse the possibility that the early hominin Ardipithecus ramidus had vocal capabilities far exceeding those of any extant non-human primate. We argue that erect posture combined with changes in craniofacial morphology, such as reduced facial and jaw length, not only provide evidence for increased levels of pro-sociality, but also increased vocal ability. Reduced length of the face and jaw, combined with a flexed cranial base, suggests the larynx in this species was situated deeper in the neck than in chimpanzees, a trait which may have facilitated increased vocal ability. We also provide evidence that Ar. ramidus, by virtue of its erect posture, possessed a degree of cervical lordosis significantly greater than chimpanzees. This is indicative of increased mobility of the larynx within the neck and hence increased capacity to modulate vocalisations. In the paleoanthropological literature, these changes in early hominin skull morphology have to date been analysed in terms of a shift in mating and social behaviour, with little consideration given to vocally mediated sociality. Similarly, in the literature on language evolution there is a distinct lacuna regarding links between craniofacial correlates of social and mating systems and vocal ability. These are surprising oversights given that pro-sociality and vocal capability require identical alterations to the common ancestral skull and skeletal configuration. We therefore propose a model which integrates data on whole organism morphogenesis with evidence for a potential early emergence of hominin socio-vocal adaptations. Consequently, we suggest vocal capability may have evolved much earlier than has been traditionally proposed. Instead of emerging in the Homo genus, we suggest the palaeoecological context of late Miocene and early Pliocene forests and woodlands facilitated the evolution of hominin socio-vocal capability. We also propose that paedomorphic morphogenesis of the skull via the process

  12. The Omo-Turkana Basin fossil hominins and their contribution to our understanding of human evolution in Africa.

    PubMed

    Wood, Bernard; Leakey, Meave

    2011-01-01

    The Omo-Turkana Basin, including the hominin fossil sites around Lake Turkana and the sites along the lower reaches of the Omo River, has made and continues to make an important contribution to improving our murky understanding of human evolution. This review highlights the various ways the Omo-Turkana Basin fossil record has contributed to, and continues to challenge, interpretations of human evolution. Despite many diagrams that look suspiciously like comprehensive hypotheses about human evolutionary history, any sensible paleoanthropologist knows that the early hominin fossil record is too meager to do anything other than offer very provisional statements about hominin taxonomy and phylogeny. If history tells us anything, it is that we still have much to learn about the hominin clade. Thus, we summarize the current state of knowledge of the hominin species represented at the Omo-Turkana Basin sites. We then focus on three specific topics for which the fossil evidence is especially relevant: the origin and nature of Paranthropus; the origin and nature of early Homo; and the ongoing debate about whether the pattern of human evolution is more consistent with speciation by cladogenesis, with greater taxonomic diversity or with speciation by anagenetic transformation, resulting in less taxonomic diversity and a more linear interpretation of human evolutionary history.

  13. Geological and taphonomic context for the new hominin species Homo naledi from the Dinaledi Chamber, South Africa

    PubMed Central

    Dirks, Paul HGM; Berger, Lee R; Roberts, Eric M; Kramers, Jan D; Hawks, John; Randolph-Quinney, Patrick S; Elliott, Marina; Musiba, Charles M; Churchill, Steven E; de Ruiter, Darryl J; Schmid, Peter; Backwell, Lucinda R; Belyanin, Georgy A; Boshoff, Pedro; Hunter, K Lindsay; Feuerriegel, Elen M; Gurtov, Alia; Harrison, James du G; Hunter, Rick; Kruger, Ashley; Morris, Hannah; Makhubela, Tebogo V; Peixotto, Becca; Tucker, Steven

    2015-01-01

    We describe the physical context of the Dinaledi Chamber within the Rising Star cave, South Africa, which contains the fossils of Homo naledi. Approximately 1550 specimens of hominin remains have been recovered from at least 15 individuals, representing a small portion of the total fossil content. Macro-vertebrate fossils are exclusively H. naledi, and occur within clay-rich sediments derived from in situ weathering, and exogenous clay and silt, which entered the chamber through fractures that prevented passage of coarser-grained material. The chamber was always in the dark zone, and not accessible to non-hominins. Bone taphonomy indicates that hominin individuals reached the chamber complete, with disarticulation occurring during/after deposition. Hominins accumulated over time as older laminated mudstone units and sediment along the cave floor were eroded. Preliminary evidence is consistent with deliberate body disposal in a single location, by a hominin species other than Homo sapiens, at an as-yet unknown date. DOI: http://dx.doi.org/10.7554/eLife.09561.001 PMID:26354289

  14. Niche partitioning in sympatric Gorilla and Pan from Cameroon: implications for life history strategies and for reconstructing the evolution of hominin life history.

    PubMed

    Macho, Gabriele A; Lee-Thorp, Julia A

    2014-01-01

    Factors influencing the hominoid life histories are poorly understood, and little is known about how ecological conditions modulate the pace of their development. Yet our limited understanding of these interactions underpins life history interpretations in extinct hominins. Here we determined the synchronisation of dental mineralization/eruption with brain size in a 20th century museum collection of sympatric Gorilla gorilla and Pan troglodytes from Central Cameroon. Using δ13C and δ15N of individuals' hair, we assessed whether and how differences in diet and habitat use may have impacted on ape development. The results show that, overall, gorilla hair δ13C and δ15N values are more variable than those of chimpanzees, and that gorillas are consistently lower in δ13C and δ15N compared to chimpanzees. Within a restricted, isotopically-constrained area, gorilla brain development appears delayed relative to dental mineralization/eruption [or dental development is accelerated relative to brains]: only about 87.8% of adult brain size is attained by the time first permanent molars come into occlusion, whereas it is 92.3% in chimpanzees. Even when M1s are already in full functional occlusion, gorilla brains lag behind those of chimpanzee (91% versus 96.4%), relative to tooth development. Both bootstrap analyses and stable isotope results confirm that these results are unlikely due to sampling error. Rather, δ15N values imply that gorillas are not fully weaned (physiologically mature) until well after M1 are in full functional occlusion. In chimpanzees the transition from infant to adult feeding appears (a) more gradual and (b) earlier relative to somatic development. Taken together, the findings are consistent with life history theory that predicts delayed development when non-density dependent mortality is low, i.e. in closed habitats, and with the "risk aversion" hypothesis for frugivorous species as a means to avert starvation. Furthermore, the results highlight

  15. Validation of bone surface modification models for inferring fossil hominin and carnivore feeding interactions, with reapplication to FLK 22, Olduvai Gorge, Tanzania.

    PubMed

    Pante, Michael C; Blumenschine, Robert J; Capaldo, Salvatore D; Scott, Robert S

    2012-08-01

    Resolving the issue of how Early Stone Age hominins acquired large mammal carcasses requires information on their feeding interactions with large carnivores. This ecological information and its behavioral and evolutionary implications are revealed most directly from the tooth, cut, and percussion marks on bone surfaces generated by hominin and carnivore feeding activities. This paper employs a bootstrap method, a form of random resampling with replacement, to refine published neotaphonomic models that use the assemblage-wide proportions of long bones bearing feeding traces to infer the sequences in which Plio-Pleistocene hominins and carnivores accessed flesh, marrow, and/or grease from carcasses. Results validate the sensitivity of the models for inferring hominin feeding ecology, which have been questioned on grounds shown here to be unfounded. The bootstrapped feeding trace models are applied to the late Pliocene larger mammal fossil assemblage from FLK 22 (Zinjanthropus site), Olduvai Gorge, Tanzania. High frequencies of tooth and percussion marking on long bone midshaft fragments from FLK 22 are most consistent with those feeding trace models that simulate hominin scavenging from carcasses defleshed by carnivores, while cut mark data indicate that hominins more often had access to upper forelimb flesh than upper hind limb flesh. Together, the bone surface modification data indicate that hominins typically gained secondary access to partially defleshed carnivore kills, but they also allow for the possibility of some carcasses being processed only by carnivores and only by hominins.

  16. The bony labyrinth of the middle Pleistocene Sima de los Huesos hominins (Sierra de Atapuerca, Spain).

    PubMed

    Quam, Rolf; Lorenzo, Carlos; Martínez, Ignacio; Gracia-Téllez, Ana; Arsuaga, Juan Luis

    2016-01-01

    We performed 3D virtual reconstructions based on CT scans to study the bony labyrinth morphology in 14 individuals from the large middle Pleistocene hominin sample from the site of the Sima de los Huesos (SH) in the Sierra de Atapuerca in northern Spain. The Atapuerca (SH) hominins represent early members of the Neandertal clade and provide an opportunity to compare the data with the later in time Neandertals, as well as Pleistocene and recent humans more broadly. The Atapuerca (SH) hominins do not differ from the Neandertals in any of the variables related to the absolute and relative sizes and shape of the semicircular canals. Indeed, the entire Neandertal clade seems to be characterized by a derived pattern of canal proportions, including a relatively small posterior canal and a relatively large lateral canal. In contrast, one of the most distinctive features observed in Neandertals, the low placement of the posterior canal (i.e., high sagittal labyrinthine index), is generally not present in the Atapuerca (SH) hominins. This low placement is considered a derived feature in Neandertals and is correlated with a more vertical orientation of the ampullar line (LSCm < APA), posterior surface of the petrous pyramid (LSCm > PPp), and third part of the facial canal (LSCm < FC3). Some variation is present within the Atapuerca (SH) sample, however, with a few individuals approaching the Neandertal condition more closely. In addition, the cochlear shape index in the Atapuerca (SH) hominins is low, indicating a reduction in the height of the cochlea. Although the phylogenetic polarity of this feature is less clear, the low shape index in the Atapuerca (SH) hominins may be a derived feature. Regardless, cochlear height subsequently increased in Neandertals. In contrast to previous suggestions, the expanded data in the present study indicate no difference across the genus Homo in the angle of inclination of the cochlear basal turn (COs < LSCm). Principal components

  17. Brain size at birth throughout human evolution: a new method for estimating neonatal brain size in hominins.

    PubMed

    DeSilva, Jeremy M; Lesnik, Julie J

    2008-12-01

    An increase in brain size is a hallmark of human evolution. Questions regarding the evolution of brain development and obstetric constraints in the human lineage can be addressed with accurate estimates of the size of the brain at birth in hominins. Previous estimates of brain size at birth in fossil hominins have been calculated from regressions of neonatal body or brain mass to adult body mass, but this approach is problematic for two reasons: modern humans are outliers for these regressions, and hominin adult body masses are difficult to estimate. To accurately estimate the brain size at birth in extinct human ancestors, an equation is needed for which modern humans fit the anthropoid regression and one in which the hominin variable entered into the regression equation has limited error. Using phylogenetically sensitive statistics, a resampling approach, and brain-mass data from the literature and from National Primate Research Centers on 362 neonates and 2802 adults from eight different anthropoid species, we found that the size of the adult brain can strongly predict the size of the neonatal brain (r2=0.97). This regression predicts human brain size, indicating that humans have precisely the brain size expected as an adult given the size of the brain at birth. We estimated the size of the neonatal brain in fossil hominins from a reduced major axis regression equation using published cranial capacities of 89 adult fossil crania. We suggest that australopiths gave birth to infants with cranial capacities that were on average 180cc (95% CI: 158-205cc), slightly larger than the average neonatal brain size of chimpanzees. Neonatal brain size increased in early Homo to 225cc (95% CI: 198-257cc) and in Homo erectus to approximately 270cc (95% CI: 237-310cc). These results have implications for interpreting the evolution of the birth process and brain development in all hominins from the australopiths and early Homo, through H. erectus, to Homo sapiens.

  18. Fossil hominin radii from the Sima de los Huesos Middle Pleistocene site (Sierra de Atapuerca, Spain).

    PubMed

    Rodríguez, Laura; Carretero, José Miguel; García-González, Rebeca; Lorenzo, Carlos; Gómez-Olivencia, Asier; Quam, Rolf; Martínez, Ignacio; Gracia-Téllez, Ana; Arsuaga, Juan Luis

    2016-01-01

    Complete radii in the fossil record preceding recent humans and Neandertals are very scarce. Here we introduce the radial remains recovered from the Sima de los Huesos (SH) site in the Sierra de Atapuerca between 1976 and 2011 and which have been dated in excess of 430 ky (thousands of years) ago. The sample comprises 89 specimens, 49 of which are attributed to adults representing a minimum of seven individuals. All elements are described anatomically and metrically, and compared with other fossil hominins and recent humans in order to examine the phylogenetic polarity of certain radial features. Radial remains from SH have some traits that differentiate them from those of recent humans and make them more similar to Neandertals, including strongly curved shafts, anteroposterior expanded radial heads and both absolutely and relatively long necks. In contrast, the SH sample differs from Neandertals in showing a high overall gracility as well as a high frequency (80%) of an anteriorly oriented radial tuberosity. Thus, like the cranial and dental remains from the SH site, characteristic Neandertal radial morphology is not present fully in the SH radii. We also analyzed the cross-sectional properties of the SH radial sample at two different levels: mid-shaft and at the midpoint of the neck length. When standardized by shaft length, no difference in the mid-shaft cross-sectional properties were found between the SH hominins, Neandertals and recent humans. Nevertheless, due to their long neck length, the SH hominins show a higher lever efficiency than either Neandertals or recent humans. Functionally, the SH radial morphology is consistent with more efficient pronation-supination and flexion-extension movements. The particular trait composition in the SH sample and Neandertals resembles more closely morphology evident in recent human males.

  19. Calcaneal robusticity in Plio-Pleistocene hominins: implications for locomotor diversity and phylogeny.

    PubMed

    Prang, Thomas C

    2015-03-01

    A key pedal adaptation to bipedality is a relatively large, weight-bearing calcaneus. The earliest evidence for a human-like, robust calcaneus is at 3.2 Ma in Australopithecus afarensis (A.L. 333-8, A.L. 333-55, A.L. 333-37) from Hadar, Ethiopia. Australopithecus sediba at 1.98 Ma from Malapa, South Africa displays a unique combination of primitive australopith features and more derived Homo-like features, but surprisingly is characterized by a gracile, chimpanzee-like calcaneus. The differences in calcaneal morphology suggest that these taxa differed in the frequency of arboreality and in the manner of foot function during terrestrial bipedal locomotion. This study examines calcaneal morphology in extant hominids (i.e., great apes and humans; N = 95) and fossil hominins (N = 5) to better understand the evolutionary development of calcaneal robusticity in early hominins. In particular, this study focuses on two additional fossil hominin calcanei that have not figured prominently in previous discussions of calcaneal robusticity: StW 352 and Omo 33-74-896. A measure of calcaneal robusticity was quantified as the ratio of calcaneal tuber cross-sectional area to calcaneal tuber length, which significantly differs between humans and non-humans using a sequential Bonferroni alpha adjustment for multiple comparisons. Additional multivariate analyses using Mosimann shape variables show that StW 352 and Omo 33-74-896 are more similar to Au. sediba in calcaneal tuber morphology than to Au. afarensis, suggesting that the latter taxon is better adapted for terrestrial bipedalism than at least some later species of Australopithecus. This finding implies the possibility of several complex evolutionary scenarios involving either multiple reversals in postcranial morphology in Australopithecus or the independent acquisition of adaptations to terrestrial bipedalism in Au. afarensis and Homo.

  20. Hominin teeth from the Middle Pleistocene site of Yiyuan, Eastern China.

    PubMed

    Xing, Song; Sun, Chengkai; Martinón-Torres, María; Bermúdez de Castro, José María; Han, Fei; Zhang, Yingqi; Liu, Wu

    2016-06-01

    In 1981-1982, some hominin fossils, including a relatively complete skull and seven isolated teeth, were recovered from the Middle Pleistocene site of Yiyuan in Eastern China. In the present study we provide a detailed metric and morphological comparison of the Yiyuan dental sample in order to characterize better the variability of the human populations that inhabited China during the Middle Pleistocene. Aside from taxonomic and phylogenetic questions, the lack of understanding and/or knowledge about the morphological variability of these populations have caused concern about the human versus non-human nature of some of the hominin dental remains found in East Asia during the Early and the Middle Pleistocene. Thus, our study aims to present a detailed description and comparison of the Yiyuan isolated teeth to 1) discuss and support their human nature and 2) to explore their taxonomic affinities with regard to other penecontemporaneous populations from Asia. Our results clearly differentiate the Yiyuan sample from Pongo specimens and support a human attribution for the Yiyuan material. Our analyses also suggest that the Yiyuan teeth form a morphologically coherent group together with samples from Zhoukoudian, Chaoxian and Hexian. They are different from the more derived specimens from Panxian Dadong, suggesting a pattern of biogeographic isolation and different evolutionary trends between northern and southern China during the Middle Pleistocene. In addition, and despite sharing a common morphological bauplan with Homo erectus sensu stricto (s.s.), the Yiyuan, Zhoukoudian and Hexian teeth are also different from the Indonesian Early Pleistocene samples. In particular, the expression of a highly crenulated or dendritic enamel-dentine surface could be unique to these groups. Our study supports the notion that the taxonomy of the Pleistocene hominins from Asia may have been oversimplified. Future studies should explore the variability of the Asian specimens and

  1. Scavenging by chimpanzees at Ngogo and the relevance of chimpanzee scavenging to early hominin behavioral ecology.

    PubMed

    Watts, David P

    2008-01-01

    Chimpanzees regularly hunt a variety of prey species. However, they rarely scavenge, which distinguishes chimpanzee carnivory from that of some modern hunter-gatherers and, presumably, at least some Plio-Pleistocene hominins. I use observations made over an 11-year period to document all known opportunities for scavenging encountered by chimpanzees at Ngogo, Kibale National Park, Uganda, and describe all cases of scavenging. I also review data on scavenging from other chimpanzee research sites. Chimpanzees at Ngogo encountered scavenging opportunities only about once per 100 days and ate meat from scavenged carcasses only four times. Scavenging opportunities are also rare at other sites, even where leopards are present (Mahale, Taï, Gombe), and scavenging of leopard kills is known only from Mahale. Feeding on prey that chimpanzees had hunted but then abandoned is the most common form of scavenging reported across study sites. For example, several individuals at Ngogo ate meat from a partially consumed red colobus carcass abandoned after a hunt the previous day. Such behavior probably was not common among Oldowan hominins. Ngogo data and those from other sites also show that chimpanzees sometimes eat meat from carcasses of prey that they did not see killed and that were not killed by chimpanzees, and that scavenging allows access to carcasses larger than those of any prey items. However, chimpanzees ignore relatively many opportunities to obtain meat from such carcasses. Scavenging may be rare because fresh carcasses are rare, because the risk of bacterial infections and zoonoses is high, and because chimpanzees may not recognize certain species as potential prey or certain size classes of prey species as food sources. Its minimal nutritional importance, along with the absence of technology to facilitate confrontational scavenging and rapid carcass processing, apparently distinguishes chimpanzee foraging strategies from those of at least some Oldowan hominins.

  2. Shared pattern of endocranial shape asymmetries among great apes, anatomically modern humans, and fossil hominins.

    PubMed

    Balzeau, Antoine; Gilissen, Emmanuel; Grimaud-Hervé, Dominique

    2011-01-01

    Anatomical asymmetries of the human brain are a topic of major interest because of their link with handedness and cognitive functions. Their emergence and occurrence have been extensively explored in human fossil records to document the evolution of brain capacities and behaviour. We quantified for the first time antero-posterior endocranial shape asymmetries in large samples of great apes, modern humans and fossil hominins through analysis of "virtual" 3D models of skull and endocranial cavity and we statistically test for departures from symmetry. Once based on continuous variables, we show that the analysis of these brain asymmetries gives original results that build upon previous analysis based on discrete traits. In particular, it emerges that the degree of petalial asymmetries differs between great apes and hominins without modification of their pattern. We indeed demonstrate the presence of shape asymmetries in great apes, with a pattern similar to modern humans but with a lower variation and a lower degree of fluctuating asymmetry. More importantly, variations in the position of the frontal and occipital poles on the right and left hemispheres would be expected to show some degree of antisymmetry when population distribution is considered, but the observed pattern of variation among the samples is related to fluctuating asymmetry for most of the components of the petalias. Moreover, the presence of a common pattern of significant directional asymmetry for two components of the petalias in hominids implicates that the observed traits were probably inherited from the last common ancestor of extant African great apes and Homo sapiens.These results also have important implications for the possible relationships between endocranial shape asymmetries and functional capacities in hominins. It emphasizes the uncoupling between lateralized activities, some of them well probably distinctive to Homo, and large-scale cerebral lateralization itself, which is not unique

  3. Metric and geometric morphometric analysis of new hominin fossils from Maba (Guangdong, China).

    PubMed

    Xiao, Dongfang; Bae, Christopher J; Shen, Guanjun; Delson, Eric; Jin, Jennie J H; Webb, Nicole M; Qiu, Licheng

    2014-09-01

    We present an analysis of a set of previously unreported hominin fossils from Maba (Guangdong, China), a cave site that is best known for the presence of a partial hominin cranium currently assigned as mid-Pleistocene Homo and that has been traditionally dated to around the Middle-Late Pleistocene transition. A more recent set of Uranium series dates indicate that the Maba travertine may date to >237 ka (thousands of years ago), as opposed to the original U-series date, which placed Maba at 135-129 ka. The fossils under study include five upper first and second molars and a partial left mandible with a socketed m3, all recovered from different parts of the site than the cranium or the dated sediments. The results of our metric and 2D geometric morphometric ('GM') study suggest that the upper first molars are likely from modern humans, suggesting a more recent origin. The upper second molars align more closely with modern humans, though the minimum spanning tree from the 2D GM analysis also connects Maba to Homo neanderthalensis. The patterning in the M2s is not as clear as with the M1s. The m3 and partial mandible are morphometrically intermediate between Holocene modern humans and older Homo sapiens. However, a minimum spanning tree indicates that both the partial mandible and m3 align most closely with Holocene modern humans, and they also may be substantially younger than the cranium. Because questions exist regarding the context and the relationship of the dated travertine with the hominin fossils, we suggest caution is warranted in interpreting the Maba specimens. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. The role of allometry and posture in the evolution of the hominin subaxial cervical spine.

    PubMed

    Arlegi, Mikel; Gómez-Olivencia, Asier; Albessard, Lou; Martínez, Ignacio; Balzeau, Antoine; Arsuaga, Juan Luis; Been, Ella

    2017-03-01

    Cervical vertebrae not only protect the spinal cord but also are the insertion and origin points for muscles related to the movement of the head, upper limb, and trunk, among others, and are thus important elements in primate evolution. While previous work has been undertaken on the first two cervical vertebrae, there is a dearth of studies on the subaxial cervical spine in hominines. In this paper, we provide detailed morphological information on two important aspects of the subaxial cervical vertebrae (C3 - C7): mid-sagittal morphology and superior facet orientation. We studied large samples of African apes including modern humans and the most complete fossil hominin subaxial cervical vertebrae using both traditional and geometric morphometrics. There are significant differences between extant hominoids related to the relative length and orientation of the spinous process as well as to the orientation of the articular facets, which are related to size, locomotion, and neck posture. In fact, fossil hominins do not completely conform to any of the extant groups. Our assessment of mid-sagittal morphology and superior articular facet orientation shows that australopiths have more Homo-like upper subaxial cervical vertebrae coupled with more "primitive" lower cervical vertebrae. Based on these results, we hypothesize that those changes, maybe related to postural changes derived from bipedalism, did not affect the entire subaxial cervical spine at once. From a methodological point of view, the combination of traditional and geometric morphometric data provides a more integrative perspective of morphological change and evolution, which is certainly useful in human evolutionary studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Metopic suture of Taung (Australopithecus africanus) and its implications for hominin brain evolution

    PubMed Central

    Falk, Dean; Zollikofer, Christoph P. E.; Morimoto, Naoki; Ponce de León, Marcia S.

    2012-01-01

    The type specimen for Australopithecus africanus (Taung) includes a natural endocast that reproduces most of the external morphology of the right cerebral hemisphere and a fragment of fossilized face that articulates with the endocast. Despite the fact that Taung died between 3 and 4 y of age, the endocast reproduces a small triangular-shaped remnant of the anterior fontanelle, from which a clear metopic suture (MS) courses rostrally along the midline [Hrdlička A (1925) Am J Phys Anthropol 8:379–392]. Here we describe and interpret this feature of Taung in light of comparative fossil and actualistic data on the timing of MS closure. In great apes, the MS normally fuses shortly after birth, such that unfused MS similar to Taung’s are rare. In humans, however, MS fuses well after birth, and partially or unfused MS are frequent. In gracile fossil adult hominins that lived between ∼3.0 and 1.5 million y ago, MS are also relatively frequent, indicating that the modern human-like pattern of late MS fusion may have become adaptive during early hominin evolution. Selective pressures favoring delayed fusion might have resulted from three aspects of perinatal ontogeny: (i) the difficulty of giving birth to large-headed neonates through birth canals that were reconfigured for bipedalism (the “obstetric dilemma”), (ii) high early postnatal brain growth rates, and (iii) reorganization and expansion of the frontal neocortex. Overall, our data indicate that hominin brain evolution occurred within a complex network of fetopelvic constraints, which required modification of frontal neurocranial ossification patterns. PMID:22566620

  6. Metopic suture of Taung (Australopithecus africanus) and its implications for hominin brain evolution.

    PubMed

    Falk, Dean; Zollikofer, Christoph P E; Morimoto, Naoki; Ponce de León, Marcia S

    2012-05-29

    The type specimen for Australopithecus africanus (Taung) includes a natural endocast that reproduces most of the external morphology of the right cerebral hemisphere and a fragment of fossilized face that articulates with the endocast. Despite the fact that Taung died between 3 and 4 y of age, the endocast reproduces a small triangular-shaped remnant of the anterior fontanelle, from which a clear metopic suture (MS) courses rostrally along the midline [Hrdlička A (1925) Am J Phys Anthropol 8:379-392]. Here we describe and interpret this feature of Taung in light of comparative fossil and actualistic data on the timing of MS closure. In great apes, the MS normally fuses shortly after birth, such that unfused MS similar to Taung's are rare. In humans, however, MS fuses well after birth, and partially or unfused MS are frequent. In gracile fossil adult hominins that lived between ∼3.0 and 1.5 million y ago, MS are also relatively frequent, indicating that the modern human-like pattern of late MS fusion may have become adaptive during early hominin evolution. Selective pressures favoring delayed fusion might have resulted from three aspects of perinatal ontogeny: (i) the difficulty of giving birth to large-headed neonates through birth canals that were reconfigured for bipedalism (the "obstetric dilemma"), (ii) high early postnatal brain growth rates, and (iii) reorganization and expansion of the frontal neocortex. Overall, our data indicate that hominin brain evolution occurred within a complex network of fetopelvic constraints, which required modification of frontal neurocranial ossification patterns.

  7. Palaeohydrological corridors for hominin dispersals in the Middle East ∼250-70,000 years ago

    NASA Astrophysics Data System (ADS)

    Breeze, Paul S.; Groucutt, Huw S.; Drake, Nick A.; White, Tom S.; Jennings, Richard P.; Petraglia, Michael D.

    2016-07-01

    The timing and extent of palaeoenvironmental connections between northeast Africa, the Levant and the Arabian Peninsula during the Middle and Late Pleistocene are critical to debates surrounding dispersals of hominins, including movements of Homo sapiens out of Africa. Although there is evidence that synchronous episodes of climatic amelioration during the late Middle and Late Pleistocene may have allowed connections to form between northern Africa and western Asia, a number of palaeoclimate models indicate the continued existence of an arid barrier between northern Arabia and the Levant. Here we evaluate the palaeoenvironmental setting for hominin dispersals between, and within, northeast Africa and southwest Asia during Marine Isotope Stages (MIS) 7-5 using reconstructions of surface freshwater availability as an environmental proxy. We use remotely sensed data to map palaeohydrological features (lakes, wetlands and rivers) across the presently hyper-arid areas of northern Arabia and surrounding regions, integrating these results with palaeoclimate models, palaeoenvironmental proxy data and absolute dating to determine when these features were active. Our analyses suggest limited potential for dispersals during MIS 7 and 6, but indicate the formation of a palaeohydrological corridor (the 'Tabuk Corridor') between the Levant and the Arabian interior during the MIS 6-5e glacial-interglacial transition and during MIS 5e. A recurrence of this corridor, following a slightly different route, also occurred during MIS 5a. These palaeohydrological and terrestrial data can be used to establish when proposed routes for hominin dispersals became viable. Furthermore, the distribution of Arabian archaeological sites with affinities to Levantine assemblages, some of which are associated with Homo sapiens fossils, and the relative density of Middle Palaeolithic assemblages within the Tabuk Corridor, are consistent with it being utilised for dispersals at various times.

  8. Isotopic evidence for dietary variability in the early hominin Paranthropus robustus.

    PubMed

    Sponheimer, Matt; Passey, Benjamin H; de Ruiter, Darryl J; Guatelli-Steinberg, Debbie; Cerling, Thure E; Lee-Thorp, Julia A

    2006-11-10

    Traditional methods of dietary reconstruction do not allow the investigation of dietary variability within the lifetimes of individual hominins. However, laser ablation stable isotope analysis reveals that the delta13C values of Paranthropus robustus individuals often changed seasonally and interannually. These data suggest that Paranthropus was not a dietary specialist and that by about 1.8 million years ago, savanna-based foods such as grasses or sedges or animals eating these foods made up an important but highly variable part of its diet.

  9. Dental microwear and stable isotopes inform the paleoecology of extinct hominins.

    PubMed

    Grine, Frederick E; Sponheimer, Matt; Ungar, Peter S; Lee-Thorp, Julia; Teaford, Mark F

    2012-06-01

    Determining the diet of an extinct species is paramount in any attempt to reconstruct its paleoecology. Because the distribution and mechanical properties of food items may impact postcranial, cranial, mandibular, and dental morphologies related to their procurement, ingestion, and mastication, these anatomical attributes have been studied intensively. However, while mechanical environments influence skeletal and dental features, it is not clear to what extent they dictate particular morphologies. Although biomechanical explanations have been widely applied to extinct hominins in attempts to retrodict dietary proclivities, morphology may say as much about what they were capable of eating, and perhaps more about phylogenetic history, than about the nature of the diet. Anatomical attributes may establish boundary limits, but direct evidence left by the foods that were actually (rather than hypothetically) consumed is required to reconstruct diet. Dental microwear and the stable light isotope chemistry of tooth enamel provide such evidence, and are especially powerful when used in tandem. We review the foundations for microwear and biogeochemistry in diet reconstruction, and discuss this evidence for six early hominin species (Ardipithecus ramidus, Australopithecus anamensis, Au. afarensis, Au. africanus, Paranthropus robustus, and P. boisei). The dietary signals derived from microwear and isotope chemistry are sometimes at odds with inferences from biomechanical approaches, a potentially disquieting conundrum that is particularly evident for several species. Copyright © 2012 Wiley Periodicals, Inc.

  10. Stone artifacts and hominins in island Southeast Asia: new insights from Flores, eastern Indonesia.

    PubMed

    Moore, Mark W; Brumm, Adam

    2007-01-01

    This study reexamines the current understanding of Pleistocene stone-artifact assemblages in island Southeast Asia. A differentiation has long been made between assemblages of large-sized "core tools" and assemblages of small-sized "flake tools." "Core tool" assemblages are often argued to be the handiwork of early hominin species such as Homo erectus, while small-sized "flake tool" assemblages have been attributed to Homo sapiens. We argue that this traditional Southeast Asian perspective on stone tools assumes that the artifacts recovered from a site reflect a complete technological sequence. Our analyses of Pleistocene-age artifact assemblages from Flores, Indonesia, demonstrate that large pebble-based cores and small flake-based cores are aspects of one reduction sequence. We propose that the Flores pattern applies across island Southeast Asia: large-sized "core tool" assemblages are in fact a missing element of the small-sized flake-based reduction sequences found in many Pleistocene caves and rock-shelters. We conclude by discussing the implications of this for associating stone-artifact assemblages with hominin species in island Southeast Asia.

  11. Rearfoot posture of Australopithecus sediba and the evolution of the hominin longitudinal arch

    PubMed Central

    Prang, Thomas C.

    2015-01-01

    The longitudinal arch is one of the hallmarks of the human foot but its evolutionary history remains controversial due to the fragmentary nature of the fossil record. In modern humans, the presence of a longitudinal arch is reflected in the angular relationships among the major surfaces of the human talus and calcaneus complex, which is also known as the rearfoot. A complete talus and calcaneus of Australopithecus sediba provide the opportunity to evaluate rearfoot posture in an early hominin for the first time. Here I show that A. sediba is indistinguishable from extant African apes in the angular configuration of its rearfoot, which strongly suggests that it lacked a longitudinal arch. Inferences made from isolated fossils support the hypothesis that Australopithecus afarensis possessed an arched foot. However, tali attributed to temporally younger taxa like Australopithecus africanus and Homo floresiensis are more similar to those of A. sediba. The inferred absence of a longitudinal arch in A. sediba would be biomechanically consistent with prior suggestions of increased midtarsal mobility in this taxon. The morphological patterns in talus and calcaneus angular relationships among fossil hominins suggest that there was diversity in traits associated with the longitudinal arch in the Plio-Pleistocene. PMID:26628197

  12. Hominin dispersal into the Nefud Desert and Middle palaeolithic settlement along the Jubbah Palaeolake, Northern Arabia.

    PubMed

    Petraglia, Michael D; Alsharekh, Abdullah; Breeze, Paul; Clarkson, Chris; Crassard, Rémy; Drake, Nick A; Groucutt, Huw S; Jennings, Richard; Parker, Adrian G; Parton, Ash; Roberts, Richard G; Shipton, Ceri; Matheson, Carney; Al-Omari, Abdulaziz; Veall, Margaret-Ashley

    2012-01-01

    The Arabian Peninsula is a key region for understanding hominin dispersals and the effect of climate change on prehistoric demography, although little information on these topics is presently available owing to the poor preservation of archaeological sites in this desert environment. Here, we describe the discovery of three stratified and buried archaeological sites in the Nefud Desert, which includes the oldest dated occupation for the region. The stone tool assemblages are identified as a Middle Palaeolithic industry that includes Levallois manufacturing methods and the production of tools on flakes. Hominin occupations correspond with humid periods, particularly Marine Isotope Stages 7 and 5 of the Late Pleistocene. The Middle Palaeolithic occupations were situated along the Jubbah palaeolake-shores, in a grassland setting with some trees. Populations procured different raw materials across the lake region to manufacture stone tools, using the implements to process plants and animals. To reach the Jubbah palaeolake, Middle Palaeolithic populations travelled into the ameliorated Nefud Desert interior, possibly gaining access from multiple directions, either using routes from the north and west (the Levant and the Sinai), the north (the Mesopotamian plains and the Euphrates basin), or the east (the Persian Gulf). The Jubbah stone tool assemblages have their own suite of technological characters, but have types reminiscent of both African Middle Stone Age and Levantine Middle Palaeolithic industries. Comparative inter-regional analysis of core technology indicates morphological similarities with the Levantine Tabun C assemblage, associated with human fossils controversially identified as either Neanderthals or Homo sapiens.

  13. A Hominin Femur with Archaic Affinities from the Late Pleistocene of Southwest China

    PubMed Central

    Liu, Wu; Bao, Zhende; Taçon, Paul S. C.; Ren, Liang

    2015-01-01

    The number of Late Pleistocene hominin species and the timing of their extinction are issues receiving renewed attention following genomic evidence for interbreeding between the ancestors of some living humans and archaic taxa. Yet, major gaps in the fossil record and uncertainties surrounding the age of key fossils have meant that these questions remain poorly understood. Here we describe and compare a highly unusual femur from Late Pleistocene sediments at Maludong (Yunnan), Southwest China, recovered along with cranial remains that exhibit a mixture of anatomically modern human and archaic traits. Our studies show that the Maludong femur has affinities to archaic hominins, especially Lower Pleistocene femora. However, the scarcity of later Middle and Late Pleistocene archaic remains in East Asia makes an assessment of systematically relevant character states difficult, warranting caution in assigning the specimen to a species at this time. The Maludong fossil probably samples an archaic population that survived until around 14,000 years ago in the biogeographically complex region of Southwest China. PMID:26678851

  14. A Hominin Femur with Archaic Affinities from the Late Pleistocene of Southwest China.

    PubMed

    Curnoe, Darren; Ji, Xueping; Liu, Wu; Bao, Zhende; Taçon, Paul S C; Ren, Liang

    2015-01-01

    The number of Late Pleistocene hominin species and the timing of their extinction are issues receiving renewed attention following genomic evidence for interbreeding between the ancestors of some living humans and archaic taxa. Yet, major gaps in the fossil record and uncertainties surrounding the age of key fossils have meant that these questions remain poorly understood. Here we describe and compare a highly unusual femur from Late Pleistocene sediments at Maludong (Yunnan), Southwest China, recovered along with cranial remains that exhibit a mixture of anatomically modern human and archaic traits. Our studies show that the Maludong femur has affinities to archaic hominins, especially Lower Pleistocene femora. However, the scarcity of later Middle and Late Pleistocene archaic remains in East Asia makes an assessment of systematically relevant character states difficult, warranting caution in assigning the specimen to a species at this time. The Maludong fossil probably samples an archaic population that survived until around 14,000 years ago in the biogeographically complex region of Southwest China.

  15. Pandora's growing box: Inferring the evolution and development of hominin brains from endocasts.

    PubMed

    Zollikofer, Christoph Peter Eduard; De León, Marcia Silvia Ponce

    2013-01-01

    The brain of modern humans is an evolutionary and developmental outlier: At birth, it has the size of an adult chimpanzee brain and expands by a factor of 2 during the first postnatal year. Large neonatal brain size and rapid initial growth contrast with slow maturation, which extends well into adolescence. When, how, and why this peculiar pattern of brain ontogeny evolved and how it is correlated with structural changes in the brain are key questions of paleoanthropology. Because brains and their ontogenies do not fossilize, indirect evidence from fossil hominin endocasts needs to be combined with evidence from modern humans and our closest living relatives, the great apes. New fossil finds permit a denser sampling of hominin endocranial morphologies along ontogenetic and evolutionary time lines. New brain imaging methods provide the basis for quantifying endocast-brain relationships and tracking endocranial and brain growth and development noninvasively. Combining this evidence with ever-more detailed knowledge about actual and fossil "brain genes," we are now beginning to understand how brain ontogeny and structure were modified during human evolution and what the adaptive significance of these modifications may have been. Copyright © 2013 Wiley Periodicals, Inc.

  16. Experimental Evidence for the Co-Evolution of Hominin Tool-Making Teaching and Language

    PubMed Central

    Morgan, T.J.H.; Uomini, N. T.; Rendell, L.E.; Chouinard-Thuly, L.; Street, S. E.; Lewis, H. M.; Cross, C. P.; Evans, C.; Kearney, R.; De la Torre, I.; Whiten, A.; Laland, K.N.

    2014-01-01

    Hominin reliance on Oldowan stone tools – which appear from 2.5mya and are believed to have been socially transmitted – has been hypothesised to have led to the evolution of teaching and language. Here we present an experiment investigating the efficacy of transmission of Oldowan tool-making skills along chains of adult human participants (N=184) using 5 different transmission mechanisms. Across six measures, transmission improves with teaching, and particularly with language, but not with imitation or emulation. Our results support the hypothesis that hominin reliance on stone tool-making generated selection for teaching and language and imply that (i) low-fidelity social transmission, such as imitation/emulation, may have contributed to the ~700,000 year stasis of the Oldowan technocomplex, and (ii) teaching or proto-language may have been pre-requisites for the appearance of Acheulean technology. This work supports a gradual evolution of language, with simple symbolic communication preceding behavioural modernity by hundreds of thousands of years. PMID:25585382

  17. A geometric morphometric analysis of hominin upper premolars. Shape variation and morphological integration.

    PubMed

    Gómez-Robles, Aida; Martinón-Torres, María; Bermúdez de Castro, José María; Prado-Simón, Leyre; Arsuaga, Juan Luis

    2011-12-01

    This paper continues the series of articles initiated in 2006 that analyse hominin dental crown morphology by means of geometric morphometric techniques. The detailed study of both upper premolar occlusal morphologies in a comprehensive sample of hominin fossils, including those coming from the Gran Dolina-TD6 and Sima de los Huesos sites from Atapuerca, Spain, complement previous works on lower first and second premolars and upper first molars. A morphological gradient consisting of the change from asymmetric to symmetric upper premolars and a marked reduction of the lingual cusp in recent Homo species has been observed in both premolars. Although percentages of correct classification based on upper premolar morphologies are not very high, significant morphological differences between Neanderthals (and European middle Pleistocene fossils) and modern humans have been identified, especially in upper second premolars. The study of morphological integration between premolar morphologies reveals significant correlations that are weaker between upper premolars than between lower ones and significant correlations between antagonists. These results have important implications for understanding the genetic and functional factors underlying dental phenotypic variation and covariation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. The Lithic Assemblages of Xiaochangliang, Nihewan Basin: Implications for Early Pleistocene Hominin Behaviour in North China

    PubMed Central

    Yang, Shi-Xia; Hou, Ya-Mei; Yue, Jian-Ping; Petraglia, Michael D.; Deng, Cheng-Long; Zhu, Ri-Xiang

    2016-01-01

    Xiaochangliang (XCL), located in the Nihewan Basin of North China, is a key archaeological locality for understanding the behavioural evolution of early humans. XCL dates to ca. 1.36 Ma, making it one of the earliest sites in Northeast Asia. Although XCL represents the first excavation of an Early Pleistocene site in the Nihewan Basin, identified and excavated in the 1970’s, the lithic assemblages have never been published in full detail. Here we describe the lithic assemblages from XCL, providing information on stone tool reduction techniques and the influence of raw materials on artefact manufacture. The XCL hominins used both bipolar and freehand reduction techniques to manufacture small flakes, some of which show retouch. Bipolar reduction methods at XCL were used more frequently than previously recognized. Comparison of XCL with other Early Pleistocene sites in the Nihewan Basin indicates the variable use of bipolar and freehand reduction methods, thereby indicating a flexible approach in the utilization of raw materials. The stone tools from XCL and the Nihewan sites are classifiable as Mode I lithic assemblages, readily distinguished from bifacial industries manufactured by hominins in Eastern Asia by ca. 800 ka. PMID:27205881

  19. Hominin Dispersal into the Nefud Desert and Middle Palaeolithic Settlement along the Jubbah Palaeolake, Northern Arabia

    PubMed Central

    Petraglia, Michael D.; Alsharekh, Abdullah; Breeze, Paul; Clarkson, Chris; Crassard, Rémy; Drake, Nick A.; Groucutt, Huw S.; Jennings, Richard; Parker, Adrian G.; Parton, Ash; Roberts, Richard G.; Shipton, Ceri; Matheson, Carney; al-Omari, Abdulaziz; Veall, Margaret-Ashley

    2012-01-01

    The Arabian Peninsula is a key region for understanding hominin dispersals and the effect of climate change on prehistoric demography, although little information on these topics is presently available owing to the poor preservation of archaeological sites in this desert environment. Here, we describe the discovery of three stratified and buried archaeological sites in the Nefud Desert, which includes the oldest dated occupation for the region. The stone tool assemblages are identified as a Middle Palaeolithic industry that includes Levallois manufacturing methods and the production of tools on flakes. Hominin occupations correspond with humid periods, particularly Marine Isotope Stages 7 and 5 of the Late Pleistocene. The Middle Palaeolithic occupations were situated along the Jubbah palaeolake-shores, in a grassland setting with some trees. Populations procured different raw materials across the lake region to manufacture stone tools, using the implements to process plants and animals. To reach the Jubbah palaeolake, Middle Palaeolithic populations travelled into the ameliorated Nefud Desert interior, possibly gaining access from multiple directions, either using routes from the north and west (the Levant and the Sinai), the north (the Mesopotamian plains and the Euphrates basin), or the east (the Persian Gulf). The Jubbah stone tool assemblages have their own suite of technological characters, but have types reminiscent of both African Middle Stone Age and Levantine Middle Palaeolithic industries. Comparative inter-regional analysis of core technology indicates morphological similarities with the Levantine Tabun C assemblage, associated with human fossils controversially identified as either Neanderthals or Homo sapiens. PMID:23185454

  20. Possible brucellosis in an early hominin skeleton from sterkfontein, South Africa.

    PubMed

    D'Anastasio, Ruggero; Zipfel, Bernhard; Moggi-Cecchi, Jacopo; Stanyon, Roscoe; Capasso, Luigi

    2009-07-30

    We report on the paleopathological analysis of the partial skeleton of the late Pliocene hominin species Australopithecus africanus Stw 431 from Sterkfontein, South Africa. A previous study noted the presence of lesions on vertebral bodies diagnosed as spondylosis deformans due to trauma. Instead, we suggest that these lesions are pathological changes due to the initial phases of an infectious disease, brucellosis. The macroscopic, microscopic and radiological appearance of the lytic lesions of the lumbar vertebrae is consistent with brucellosis. The hypothesis of brucellosis (most often associated with the consumption of animal proteins) in a 2.4 to 2.8 million year old hominid has a host of important implications for human evolution. The consumption of meat has been regarded an important factor in supporting, directing or altering human evolution. Perhaps the earliest (up to 2.5 million years ago) paleontological evidence for meat eating consists of cut marks on animal remains and stone tools that could have made these marks. Now with the hypothesis of brucellosis in A. africanus, we may have evidence of occasional meat eating directly linked to a fossil hominin.

  1. Paleoecological patterns at the Hadar hominin site, Afar Regional State, Ethiopia.

    PubMed

    Reed, Kaye E

    2008-06-01

    Reconstructing paleoecological patterns associated with hominin taxa, such as Australopithecus afarensis, is important for understanding possible evolutionary mechanisms involved in extinction and speciation events. It is critical to identify local, regional, or pan-African causal factors because patterns at these different levels may affect separate populations of the same species of hominin in unique ways. Habitat reconstructions of 12 submembers of the Hadar and Busidima formations (approximately 3.8-2.35 Ma) are presented here along with faunal differences in these submembers through time. Habitats with medium density tree and bush cover dominated the landscape through much of the earlier time period in the Hadar Formation. The lowermost Sidi Hakoma Member is the most closed habitat. The Denen Dora Member shows the influence of frequent floodplain edaphic grasslands with high abundances of reducin bovids. There is an influx of ungulates in the Kada Hadar Member (approximately 3.2--approximately 2.96 Ma) that indicates a more arid habitat populated by mammals that were recovered from earlier deposits further south in Ethiopia and Kenya. In the younger deposits from the Busidima Formation at Hadar, the landscape was open wooded grassland with some floodplain environments. The fossil assemblages from the Busidima Formation show a substantial species turnover. Although high numbers of A. afarensis specimens are associated with the lower Sidi Hakoma Member, they clearly inhabited a variety of habitats throughout the entire Hadar Formation. Australopithecus afarensis from Laetoli through Hadar times appears to have been a eurytopic species.

  2. Was Australopithecus anamensis ancestral to A. afarensis? A case of anagenesis in the hominin fossil record.

    PubMed

    Kimbel, William H; Lockwood, Charles A; Ward, Carol V; Leakey, Meave G; Rak, Yoel; Johanson, Donald C

    2006-08-01

    We tested the hypothesis that early Pliocene Australopithecus anamensis was ancestral to A. afarensis by conducting a phylogenetic analysis of four temporally successive fossil samples assigned to these species (from earliest to latest: Kanapoi, Allia Bay, Laetoli, Hadar) using polarized character-state data from 20 morphological characters of the dentition and jaws. If the hypothesis that A. anamensis is ancestral to A. afarensis is true, then character-state changes between the temporally ordered site-samples should be congruent with hypothesized polarity transformations based on outgroup (African great ape) conditions. The most parsimonious reconstruction of character-state evolution suggests that each of the hominin OTUs shares apomorphies only with geologically younger OTUs, as predicted by the hypothesis of ancestry (tree length=31; Consistency Index=0.903). This concordance of stratigraphic and character-state data supports the idea that the A. anamensis and A. afarensis samples represent parts of an anagenetically evolving lineage, or evolutionary species. Each site-sample appears to capture a different point along this evolutionary trajectory. We discuss the implications of this conclusion for the taxonomy and adaptive evolution of these early-middle Pliocene hominins.

  3. Possible Brucellosis in an Early Hominin Skeleton from Sterkfontein, South Africa

    PubMed Central

    D'Anastasio, Ruggero; Zipfel, Bernhard; Moggi-Cecchi, Jacopo; Stanyon, Roscoe; Capasso, Luigi

    2009-01-01

    We report on the paleopathological analysis of the partial skeleton of the late Pliocene hominin species Australopithecus africanus Stw 431 from Sterkfontein, South Africa. A previous study noted the presence of lesions on vertebral bodies diagnosed as spondylosis deformans due to trauma. Instead, we suggest that these lesions are pathological changes due to the initial phases of an infectious disease, brucellosis. The macroscopic, microscopic and radiological appearance of the lytic lesions of the lumbar vertebrae is consistent with brucellosis. The hypothesis of brucellosis (most often associated with the consumption of animal proteins) in a 2.4 to 2.8 million year old hominid has a host of important implications for human evolution. The consumption of meat has been regarded an important factor in supporting, directing or altering human evolution. Perhaps the earliest (up to 2.5 million years ago) paleontological evidence for meat eating consists of cut marks on animal remains and stone tools that could have made these marks. Now with the hypothesis of brucellosis in A. africanus, we may have evidence of occasional meat eating directly linked to a fossil hominin. PMID:19649274

  4. Hard-Object Feeding in Sooty Mangabeys (Cercocebus atys) and Interpretation of Early Hominin Feeding Ecology

    PubMed Central

    Daegling, David J.; McGraw, W. Scott; Ungar, Peter S.; Pampush, James D.; Vick, Anna E.; Bitty, E. Anderson

    2011-01-01

    Morphology of the dentofacial complex of early hominins has figured prominently in the inference of their dietary adaptations. Recent theoretical analysis of craniofacial morphology of Australopithecus africanus proposes that skull form in this taxon represents adaptation to feeding on large, hard objects. A modern analog for this specific dietary specialization is provided by the West African sooty mangabey, Cercocebus atys. This species habitually feeds on the large, exceptionally hard nuts of Sacoglottis gabonensis, stereotypically crushing the seed casings using their premolars and molars. This type of behavior has been inferred for A. africanus based on mathematical stress analysis and aspects of dental wear and morphology. While postcanine megadontia, premolar enlargement and thick molar enamel characterize both A. africanus and C. atys, these features are not universally associated with durophagy among living anthropoids. Occlusal microwear analysis reveals complex microwear textures in C. atys unlike those observed in A. africanus, but more closely resembling textures observed in Paranthropus robustus. Since sooty mangabeys process hard objects in a manner similar to that proposed for A. africanus, yet do so without the craniofacial buttressing characteristic of this hominin, it follows that derived features of the australopith skull are sufficient but not necessary for the consumption of large, hard objects. The adaptive significance of australopith craniofacial morphology may instead be related to the toughness, rather than the hardness, of ingested foods. PMID:21887229

  5. Rearfoot posture of Australopithecus sediba and the evolution of the hominin longitudinal arch.

    PubMed

    Prang, Thomas C

    2015-12-02

    The longitudinal arch is one of the hallmarks of the human foot but its evolutionary history remains controversial due to the fragmentary nature of the fossil record. In modern humans, the presence of a longitudinal arch is reflected in the angular relationships among the major surfaces of the human talus and calcaneus complex, which is also known as the rearfoot. A complete talus and calcaneus of Australopithecus sediba provide the opportunity to evaluate rearfoot posture in an early hominin for the first time. Here I show that A. sediba is indistinguishable from extant African apes in the angular configuration of its rearfoot, which strongly suggests that it lacked a longitudinal arch. Inferences made from isolated fossils support the hypothesis that Australopithecus afarensis possessed an arched foot. However, tali attributed to temporally younger taxa like Australopithecus africanus and Homo floresiensis are more similar to those of A. sediba. The inferred absence of a longitudinal arch in A. sediba would be biomechanically consistent with prior suggestions of increased midtarsal mobility in this taxon. The morphological patterns in talus and calcaneus angular relationships among fossil hominins suggest that there was diversity in traits associated with the longitudinal arch in the Plio-Pleistocene.

  6. Experimental evidence for the co-evolution of hominin tool-making teaching and language.

    PubMed

    Morgan, T J H; Uomini, N T; Rendell, L E; Chouinard-Thuly, L; Street, S E; Lewis, H M; Cross, C P; Evans, C; Kearney, R; de la Torre, I; Whiten, A; Laland, K N

    2015-01-13

    Hominin reliance on Oldowan stone tools-which appear from 2.5 mya and are believed to have been socially transmitted-has been hypothesized to have led to the evolution of teaching and language. Here we present an experiment investigating the efficacy of transmission of Oldowan tool-making skills along chains of adult human participants (N=184) using five different transmission mechanisms. Across six measures, transmission improves with teaching, and particularly with language, but not with imitation or emulation. Our results support the hypothesis that hominin reliance on stone tool-making generated selection for teaching and language, and imply that (i) low-fidelity social transmission, such as imitation/emulation, may have contributed to the ~700,000 year stasis of the Oldowan technocomplex, and (ii) teaching or proto-language may have been pre-requisites for the appearance of Acheulean technology. This work supports a gradual evolution of language, with simple symbolic communication preceding behavioural modernity by hundreds of thousands of years.

  7. Multiple Cross-Species Transmission Events of Human Adenoviruses (HAdV) during Hominine Evolution

    PubMed Central

    Hoppe, Eileen; Pauly, Maude; Gillespie, Thomas R.; Akoua-Koffi, Chantal; Hohmann, Gottfried; Fruth, Barbara; Karhemere, Stomy; Madinda, Nadège F.; Mugisha, Lawrence; Muyembe, Jean-Jacques; Todd, Angelique; Petrzelkova, Klara J.; Gray, Maryke; Robbins, Martha; Bergl, Richard A.; Wittig, Roman M.; Zuberbühler, Klaus; Boesch, Christophe; Schubert, Grit; Leendertz, Fabian H.; Ehlers, Bernhard; Calvignac-Spencer, Sébastien

    2015-01-01

    Human adenoviruses (HAdV; species HAdV-A to -G) are highly prevalent in the human population, and represent an important cause of morbidity and, to a lesser extent, mortality. Recent studies have identified close relatives of these viruses in African great apes, suggesting that some HAdV may be of zoonotic origin. We analyzed more than 800 fecal samples from wild African great apes and humans to further investigate the evolutionary history and zoonotic potential of hominine HAdV. HAdV-B and -E were frequently detected in wild gorillas (55%) and chimpanzees (25%), respectively. Bayesian ancestral host reconstruction under discrete diffusion models supported a gorilla and chimpanzee origin for these viral species. Host switches were relatively rare along HAdV evolution, with about ten events recorded in 4.5 My. Despite presumably rare direct contact between sympatric populations of the two species, transmission events from gorillas to chimpanzees were observed, suggesting that habitat and dietary overlap may lead to fecal-oral cross-hominine transmission of HAdV. Finally, we determined that two independent HAdV-B transmission events to humans occurred more than 100,000 years ago. We conclude that HAdV-B circulating in humans are of zoonotic origin and have probably affected global human health for most of our species lifetime. PMID:25862141

  8. Termites in the hominin diet: a meta-analysis of termite genera, species and castes as a dietary supplement for South African robust australopithecines.

    PubMed

    Lesnik, Julie J

    2014-06-01

    Termite foraging by chimpanzees and present-day modern humans is a well-documented phenomenon, making it a plausible hypothesis that early hominins were also utilizing this resource. Hominin termite foraging has been credited by some to be the explanation for the unexpected carbon isotope signatures present in South African hominin teeth, which suggest the diet was different from that of extant non-human great apes, consisting of a significant amount of resources that are not from woody-plants. Grass-eating termites are one potential resource that could contribute to the carbon signature. However, not all termites eat grasses, and in fact, the termites that are most widely consumed by chimpanzees and by many present-day human populations at best have a mixed diet that includes small amounts of grasses. Here I review the ecology of termites and how it affects their desirability as a food resource for hominins, and conduct a meta-analysis of nutritional values for various genera, species and castes from the literature. Termites are very diverse, even within species, and this variability affects both their carbon signatures and nutritional value, hindering generalizations regarding the contribution of termites to the hominin diet. It is concluded here that a combination of soldiers and alates of the genus Macrotermes be used to model the insectivory component of the Plio-Pleistocene hominin diet due to their significant amounts of energy-yielding nutrients and potential role as a critical resource for supporting larger-brained hominins.

  9. Hominin-bearing caves and landscape dynamics in the Cradle of Humankind, South Africa

    NASA Astrophysics Data System (ADS)

    Dirks, Paul H. G. M.; Berger, Lee R.

    2013-02-01

    This paper provides constraints on the evolution of the landscape in the Cradle of Humankind (CoH), UNESCO World Heritage Site, South Africa, since the Pliocene. The aim is to better understand the distribution of hominin fossils in the CoH, and determine links between tectonic processes controlling the landscape and the evolution and distribution of hominins occupying that landscape. The paper is focused on a detailed reconstruction of the landscape through time in the Grootvleispruit catchment, which contains the highly significant fossil site of Malapa and the remains of the hominin species Australopithicus sediba. In the past 4 My the landscape in the CoH has undergone major changes in its physical appearance as a result of river incision, which degraded older African planation surfaces, and accommodated denudation of cover rocks (including Karoo sediments and various sil- and ferricretes) to expose dolomite with caves in which fossils collected. Differentially weathered chert breccia dykes, calibrated with 10Be exposure ages, are used to estimate erosion patterns of the landscape across the CoH. In this manner it is shown that 2 My ago Malapa cave was ˜50 m deep, and Gladysvale cave was first exposed; i.e. landscape reconstructions can provide estimates for the time of opening of cave systems that trapped hominin and other fossils. Within the region, cave formation was influenced by lithological, layer-parallel controls interacting with cross-cutting fracture systems of Paleoproterozoic origin, and a NW-SE directed extensional far-field stress at a time when the African erosion surface was still intact, and elevations were probably lower. Cave geometries vary in a systematic manner across the landscape, with deep caves on the plateau and cave erosion remnants in valleys. Most caves formed to similar depths of 1400-1420 mamsl across much of the CoH, indicating that caves no longer deepened once Pliocene uplift and incision occurred, but acted as passive

  10. Learning Model of Unggah-Ungguh Basa Oriented to Noble Behavior in SMP (Junior High School) Jawa Timur (East Java) Indonesia

    ERIC Educational Resources Information Center

    Sudikan, Setya Yuwana

    2017-01-01

    Learning problem of "unggah-ungguh basa", is very complicated. It is needed reorientation and re-setting the approaches, strategies, methods, techniques, and learning contents that can give rise to a new model of learning of "unggah-ungguh basa" oriented to the character formation of children, especially in Jawa Timur. In…

  11. ‘Captivity bias’ in animal tool use and its implications for the evolution of hominin technology

    PubMed Central

    Haslam, Michael

    2013-01-01

    Animals in captive or laboratory settings may outperform wild animals of the same species in both frequency and diversity of tool use, a phenomenon here termed ‘captivity bias’. Although speculative at this stage, a logical conclusion from this concept is that animals whose tool-use behaviour is observed solely under natural conditions may be judged cognitively or physically inferior than if they had also been tested or observed under controlled captive conditions. In turn, this situation creates a potential problem for studies of the behaviour of extinct members of the human family tree—the hominins—as hominin cognitive abilities are often judged on material evidence of tool-use behaviour left in the archaeological record. In this review, potential factors contributing to captivity bias in primates (including increased contact between individuals engaged in tool use, guidance or shaping of tool-use behaviour by other tool-users and increased free time and energy) are identified and assessed for their possible effects on the behaviour of the Late Pleistocene hominin Homo floresiensis. The captivity bias concept provides one way to uncouple hominin tool use from cognition, by considering hominins as subject to the same adaptive influences as other tool-using animals. PMID:24101629

  12. Early hominin diet included diverse terrestrial and aquatic animals 1.95 Ma in East Turkana, Kenya

    PubMed Central

    Braun, David R.; Harris, John W. K.; Levin, Naomi E.; McCoy, Jack T.; Herries, Andy I. R.; Bamford, Marion K.; Bishop, Laura C.; Richmond, Brian G.; Kibunjia, Mzalendo

    2010-01-01

    The manufacture of stone tools and their use to access animal tissues by Pliocene hominins marks the origin of a key adaptation in human evolutionary history. Here we report an in situ archaeological assemblage from the Koobi Fora Formation in northern Kenya that provides a unique combination of faunal remains, some with direct evidence of butchery, and Oldowan artifacts, which are well dated to 1.95 Ma. This site provides the oldest in situ evidence that hominins, predating Homo erectus, enjoyed access to carcasses of terrestrial and aquatic animals that they butchered in a well-watered habitat. It also provides the earliest definitive evidence of the incorporation into the hominin diet of various aquatic animals including turtles, crocodiles, and fish, which are rich sources of specific nutrients needed in human brain growth. The evidence here shows that these critical brain-growth compounds were part of the diets of hominins before the appearance of Homo ergaster/erectus and could have played an important role in the evolution of larger brains in the early history of our lineage. PMID:20534571

  13. The oldest hominin butchery in European mid-latitudes at the Jaramillo site of Untermassfeld (Thuringia, Germany).

    PubMed

    Landeck, Günter; Garcia Garriga, Joan

    2016-05-01

    The late Early Pleistocene site of Untermassfeld, dated to the Jaramillo subchron (ca. 1.07 millions of years ago), is well known for its rich Epivillafranchian fauna. It has also recently yielded stone artefacts attesting hominin occupation. Now, we report here, for the first time, evidence of hominin butchery such as cut marks and intentional hammerstone-related bone breakage. This probable subsistence behaviour was detected in a small faunal subsample recovered from levels with Mode 1 stone tools. The butchered faunal assemblage was found during fieldwork and surveying in fluvial riverbanks (Lower Fluviatile Sands) and channel erosion sediments (Upper Fluviatile Sands). The frequent occurrence of butchery traces on bones of large-sized herd animals (i.e., Bison) may imply a greater need for meat in seasonal habitats characterised by a depletion of nutritive plants in winter. Early access to carcasses, before their consumption by carnivores, provided hominins with sufficient quantities of meat. This access was acquired with a Mode 1 lithic industry, to ensure food procurement and survival at high latitudes in Europe. Stone tools and faunal remains with signs of anthropic intervention recovered at Untermassfeld are evidence of the oldest hominin settlement at continental mid-latitudes (50° N).

  14. Effect of ancient population structure on the degree of polymorphism shared between modern human populations and ancient hominins.

    PubMed

    Eriksson, Anders; Manica, Andrea

    2012-08-28

    Recent comparisons between anatomically modern humans and ancient genomes of other hominins have raised the tantalizing, and hotly debated, possibility of hybridization. Although several tests of hybridization have been devised, they all rely on the degree to which different modern populations share genetic polymorphisms with the ancient genomes of other hominins. However, spatial population structure is expected to generate genetic patterns similar to those that might be attributed to hybridization. To investigate this problem, we take Neanderthals as a case study, and build a spatially explicit model of the shared history of anatomically modern humans and this hominin. We show that the excess polymorphism shared between Eurasians and Neanderthals is compatible with scenarios in which no hybridization occurred, and is strongly linked to the strength of population structure in ancient populations. Thus, we recommend caution in inferring admixture from geographic patterns of shared polymorphisms, and argue that future attempts to investigate ancient hybridization between humans and other hominins should explicitly account for population structure.

  15. Measures of maturation in early fossil hominins: events at the first transition from australopiths to early Homo.

    PubMed

    Dean, M Christopher

    2016-07-05

    An important question in palaeoanthropology is whether, among the australopiths and the first fossil hominins attributed to early Homo, there was a shift towards a more prolonged period of growth that can be distinguished from that of the living great apes and whether between the end of weaning and the beginning of puberty there was a slow period of growth as there is in modern humans. Evidence for the pace of growth in early fossil hominins comes from preserved tooth microstructure. A record of incremental growth in enamel and dentine persists, which allows us to reconstruct tooth growth and compare key measures of dental maturation with modern humans and living great apes. Despite their diverse diets and way of life, it is currently difficult to identify any clear differences in the timing of dental development among living great apes, australopiths and the earliest hominins attributed to the genus Homo There is, however, limited evidence that some early hominins may have attained a greater proportion of their body mass and stature relatively earlier in the growth period than is typical of modern humans today.This article is part of the themed issue 'Major transitions in human evolution'. © 2016 The Author(s).

  16. A geometric morphometric analysis of hominin upper second and third molars, with particular emphasis on European Pleistocene populations.

    PubMed

    Gómez-Robles, Aida; Bermúdez de Castro, José María; Martinón-Torres, María; Prado-Simón, Leyre; Arsuaga, Juan Luis

    2012-09-01

    The study of dental morphology by means of geometric morphometric methods allows for a detailed and quantitative comparison of hominin species that is useful for taxonomic assignment and phylogenetic reconstruction. Upper second and third molars have been studied in a comprehensive sample of Plio- and Pleistocene hominins from African, Asian and European sites in order to complete our analysis of the upper postcanine dentition. Intraspecific variation in these two molars is high, but some interspecific trends can be identified. Both molars exhibit a strong reduction of the distal cusps in recent hominin species, namely European Homo heidelbergensis, Homo neanderthalensis and Homo sapiens, but this reduction shows specific patterns and proportions in the three groups. Second molars tend to show four well developed cusps in earlier hominin species and their morphology is only marginally affected by allometric effects. Third molars can be incipiently reduced in earlier species and they evince a significant allometric component, identified both inter- and intraspecifically. European Middle Pleistocene fossils from Sima de los Huesos (SH) show a very strong reduction of these two molars, even more marked than the reduction observed in Neanderthals and in modern human populations. The highly derived shape of SH molars points to an early acquisition of typical Neanderthal dental traits by pre-Neanderthal populations and to a deviation of this population from mean morphologies of other European Middle Pleistocene groups. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Measures of maturation in early fossil hominins: events at the first transition from australopiths to early Homo

    PubMed Central

    Dean, M. Christopher

    2016-01-01

    An important question in palaeoanthropology is whether, among the australopiths and the first fossil hominins attributed to early Homo, there was a shift towards a more prolonged period of growth that can be distinguished from that of the living great apes and whether between the end of weaning and the beginning of puberty there was a slow period of growth as there is in modern humans. Evidence for the pace of growth in early fossil hominins comes from preserved tooth microstructure. A record of incremental growth in enamel and dentine persists, which allows us to reconstruct tooth growth and compare key measures of dental maturation with modern humans and living great apes. Despite their diverse diets and way of life, it is currently difficult to identify any clear differences in the timing of dental development among living great apes, australopiths and the earliest hominins attributed to the genus Homo. There is, however, limited evidence that some early hominins may have attained a greater proportion of their body mass and stature relatively earlier in the growth period than is typical of modern humans today. This article is part of the themed issue ‘Major transitions in human evolution’. PMID:27298465

  18. The Hominin Sites and Paleolakes Drilling Project: inferring the environmental context of human evolution from eastern African rift lake deposits

    NASA Astrophysics Data System (ADS)

    Cohen, A.; Campisano, C.; Arrowsmith, R.; Asrat, A.; Behrensmeyer, A. K.; Deino, A.; Feibel, C.; Hill, A.; Johnson, R.; Kingston, J.; Lamb, H.; Lowenstein, T.; Noren, A.; Olago, D.; Owen, R. B.; Potts, R.; Reed, K.; Renaut, R.; Schäbitz, F.; Tiercelin, J.-J.; Trauth, M. H.; Wynn, J.; Ivory, S.; Brady, K.; O'Grady, R.; Rodysill, J.; Githiri, J.; Russell, J.; Foerster, V.; Dommain, R.; Rucina, S.; Deocampo, D.; Russell, J.; Billingsley, A.; Beck, C.; Dorenbeck, G.; Dullo, L.; Feary, D.; Garello, D.; Gromig, R.; Johnson, T.; Junginger, A.; Karanja, M.; Kimburi, E.; Mbuthia, A.; McCartney, T.; McNulty, E.; Muiruri, V.; Nambiro, E.; Negash, E. W.; Njagi, D.; Wilson, J. N.; Rabideaux, N.; Raub, T.; Sier, M. J.; Smith, P.; Urban, J.; Warren, M.; Yadeta, M.; Yost, C.; Zinaye, B.

    2016-02-01

    The role that climate and environmental history may have played in influencing human evolution has been the focus of considerable interest and controversy among paleoanthropologists for decades. Prior attempts to understand the environmental history side of this equation have centered around the study of outcrop sediments and fossils adjacent to where fossil hominins (ancestors or close relatives of modern humans) are found, or from the study of deep sea drill cores. However, outcrop sediments are often highly weathered and thus are unsuitable for some types of paleoclimatic records, and deep sea core records come from long distances away from the actual fossil and stone tool remains. The Hominin Sites and Paleolakes Drilling Project (HSPDP) was developed to address these issues. The project has focused its efforts on the eastern African Rift Valley, where much of the evidence for early hominins has been recovered. We have collected about 2 km of sediment drill core from six basins in Kenya and Ethiopia, in lake deposits immediately adjacent to important fossil hominin and archaeological sites. Collectively these cores cover in time many of the key transitions and critical intervals in human evolutionary history over the last 4 Ma, such as the earliest stone tools, the origin of our own genus Homo, and the earliest anatomically modern Homo sapiens. Here we document the initial field, physical property, and core description results of the 2012-2014 HSPDP coring campaign.

  19. Evaluating morphometric body mass prediction equations with a juvenile human test sample: accuracy and applicability to small-bodied hominins.

    PubMed

    Walker, Christopher S; Yapuncich, Gabriel S; Sridhar, Shilpa; Cameron, Noël; Churchill, Steven E

    2017-05-02

    Body mass is an ecologically and biomechanically important variable in the study of hominin biology. Regression equations derived from recent human samples allow for the reasonable prediction of body mass of later, more human-like, and generally larger hominins from hip joint dimensions, but potential differences in hip biomechanics across hominin taxa render their use questionable with some earlier taxa (i.e., Australopithecus spp.). Morphometric prediction equations using stature and bi-iliac breadth avoid this problem, but their applicability to early hominins, some of which differ in both size and proportions from modern adult humans, has not been demonstrated. Here we use mean stature, bi-iliac breadth, and body mass from a global sample of human juveniles ranging in age from 6 to 12 years (n = 530 age- and sex-specific group annual means from 33 countries/regions) to evaluate the accuracy of several published morphometric prediction equations when applied to small humans. Though the body proportions of modern human juveniles likely differ from those of small-bodied early hominins, human juveniles (like fossil hominins) often differ in size and proportions from adult human reference samples and, accordingly, serve as a useful model for assessing the robustness of morphometric prediction equations. Morphometric equations based on adults systematically underpredict body mass in the youngest age groups and moderately overpredict body mass in the older groups, which fall in the body size range of adult Australopithecus (∼26-46 kg). Differences in body proportions, notably the ratio of lower limb length to stature, influence predictive accuracy. Ontogenetic changes in these body proportions likely influence the shift in prediction error (from under- to overprediction). However, because morphometric equations are reasonably accurate when applied to this juvenile test sample, we argue these equations may be used to predict body mass in small-bodied hominins

  20. New immature hominin fossil from European Lower Pleistocene shows the earliest evidence of a modern human dental development pattern.

    PubMed

    Bermúdez de Castro, José María; Martinón-Torres, María; Prado, Leyre; Gómez-Robles, Aida; Rosell, Jordi; López-Polín, Lucía; Arsuaga, Juan Luís; Carbonell, Eudald

    2010-06-29

    Here we present data concerning the pattern of dental development derived from the microcomputed tomography (microCT) study of a recently discovered immature hominin mandible with a mixed dentition recovered from the TD6 level of the Gran Dolina Lower Pleistocene cave site in Sierra de Atapuerca, northern Spain. These data confirm our previous results that nearly 1 million years ago at least one European hominin species had a fully modern pattern of dental development with a clear slowdown in the development of the molar field regarding the anterior dental field. Furthermore, using available information about enamel formation times and root extension rates in chimpanzees, early hominins, and modern humans, we have estimated that the formation time of the upper and lower first molars of individual 5 (H5) from TD6, which had just erupted at the time of the death of this individual, ranges between 5.3 and 6.6 y. Therefore, the eruption time of the first permanent molars (M1) in the TD6 hominins was within the range of variation of modern human populations. Because the time of M1 eruption in primates is a robust marker of life history, we suggest, as a working hypothesis, that these hominins had a prolonged childhood in the range of the variation of modern humans. If this hypothesis is true, it implies that the appearance in Homo of this important developmental biological feature and an associated increase in brain size preceded the development of the neocortical areas leading to the cognitive capabilities that are thought to be exclusive to Homo sapiens.

  1. New immature hominin fossil from European Lower Pleistocene shows the earliest evidence of a modern human dental development pattern

    PubMed Central

    Bermúdez de Castro, José María; Martinón-Torres, María; Prado, Leyre; Gómez-Robles, Aida; Rosell, Jordi; López-Polín, Lucía; Arsuaga, Juan Luís; Carbonell, Eudald

    2010-01-01

    Here we present data concerning the pattern of dental development derived from the microcomputed tomography (microCT) study of a recently discovered immature hominin mandible with a mixed dentition recovered from the TD6 level of the Gran Dolina Lower Pleistocene cave site in Sierra de Atapuerca, northern Spain. These data confirm our previous results that nearly 1 million years ago at least one European hominin species had a fully modern pattern of dental development with a clear slowdown in the development of the molar field regarding the anterior dental field. Furthermore, using available information about enamel formation times and root extension rates in chimpanzees, early hominins, and modern humans, we have estimated that the formation time of the upper and lower first molars of individual 5 (H5) from TD6, which had just erupted at the time of the death of this individual, ranges between 5.3 and 6.6 y. Therefore, the eruption time of the first permanent molars (M1) in the TD6 hominins was within the range of variation of modern human populations. Because the time of M1 eruption in primates is a robust marker of life history, we suggest, as a working hypothesis, that these hominins had a prolonged childhood in the range of the variation of modern humans. If this hypothesis is true, it implies that the appearance in Homo of this important developmental biological feature and an associated increase in brain size preceded the development of the neocortical areas leading to the cognitive capabilities that are thought to be exclusive to Homo sapiens. PMID:20547843

  2. Palaeoproteomic evidence identifies archaic hominins associated with the Châtelperronian at the Grotte du Renne

    PubMed Central

    Welker, Frido; Hajdinjak, Mateja; Talamo, Sahra; Jaouen, Klervia; Dannemann, Michael; David, Francine; Julien, Michèle; Meyer, Matthias; Barnes, Ian; Brace, Selina; Kamminga, Pepijn; Fischer, Roman; Kessler, Benedikt M.; Stewart, John R.; Pääbo, Svante; Collins, Matthew J.; Hublin, Jean-Jacques

    2016-01-01

    In Western Europe, the Middle to Upper Paleolithic transition is associated with the disappearance of Neandertals and the spread of anatomically modern humans (AMHs). Current chronological, behavioral, and biological models of this transitional period hinge on the Châtelperronian technocomplex. At the site of the Grotte du Renne, Arcy-sur-Cure, morphological Neandertal specimens are not directly dated but are contextually associated with the Châtelperronian, which contains bone points and beads. The association between Neandertals and this “transitional” assemblage has been controversial because of the lack either of a direct hominin radiocarbon date or of molecular confirmation of the Neandertal affiliation. Here we provide further evidence for a Neandertal–Châtelperronian association at the Grotte du Renne through biomolecular and chronological analysis. We identified 28 additional hominin specimens through zooarchaeology by mass spectrometry (ZooMS) screening of morphologically uninformative bone specimens from Châtelperronian layers at the Grotte du Renne. Next, we obtain an ancient hominin bone proteome through liquid chromatography-MS/MS analysis and error-tolerant amino acid sequence analysis. Analysis of this palaeoproteome allows us to provide phylogenetic and physiological information on these ancient hominin specimens. We distinguish Late Pleistocene clades within the genus Homo based on ancient protein evidence through the identification of an archaic-derived amino acid sequence for the collagen type X, alpha-1 (COL10α1) protein. We support this by obtaining ancient mtDNA sequences, which indicate a Neandertal ancestry for these specimens. Direct accelerator mass spectometry radiocarbon dating and Bayesian modeling confirm that the hominin specimens date to the Châtelperronian at the Grotte du Renne. PMID:27638212

  3. The pattern of hominin postcranial evolution reconsidered in light of size-related shape variation of the distal humerus.

    PubMed

    Lague, Michael R

    2014-10-01

    Previous research suggests that some hominin postcranial features do not follow a linear path of increasing modernization through geological time. With respect to the distal humerus, in particular, the earliest known hominin specimens are reportedly among the most modern in morphology, while some later humeri appear further removed from the average modern human shape. Although Plio-Pleistocene humeri vary widely in size, previous studies have failed to account for size-related shape variation when making morphometric comparisons. This study reexamines hominin postcranial evolution in light of distal humeral allometry. Using two-dimensional landmark data, the relationship between specimen size and shape among modern humans is quantified using multivariate regression and principal components analysis of size-shape space. Fossils are compared with modern human shapes expected at a given size, as well as with the overall average human shape. The null hypothesis of humeral isometry in modern humans is rejected. Subsequently, if one takes allometry into account, the apparent pattern of hominin humeral evolution does not resemble the pattern described above. All 14 of the Plio-Pleistocene hominin fossils examined here share a similar pattern of shape differences from equivalently-sized modern humans, though they vary in the extent to which these differences are expressed. The oldest specimen in the sample (KNM-KP 271; Australopithecus anamensis) exhibits the least human-like elbow morphology. Similarly primitive morphology characterizes all younger species of Australopithecus as well as Paranthropus robustus. After 2 Ma, a subtly more human-like elbow morphology is apparent among specimens attributed to early Homo, as well as among isolated specimens that may represent either Homo or Paranthropus boisei. This study emphasizes the need to consider size-related shape variation when individual fossil specimens are compared with the average shape of a comparative group

  4. Mass spectrometric U-series dating of Huanglong Cave in Hubei Province, Central China: evidence for early presence of modern humans in Eastern Asia.

    PubMed

    Shen, Guanjun; Wu, Xianzhu; Wang, Qian; Tu, Hua; Feng, Yue-xing; Zhao, Jian-xin

    2013-08-01

    Most researchers believe that anatomically modern humans (AMH) first appeared in Africa 160-190 ka ago, and would not have reached eastern Asia until ∼50 ka ago. However, the credibility of these scenarios might have been compromised by a largely inaccurate and compressed chronological framework previously established for hominin fossils found in China. Recently there has been a growing body of evidence indicating the possible presence of AMH in eastern Asia ca. 100 ka ago or even earlier. Here we report high-precision mass spectrometric U-series dating of intercalated flowstone samples from Huanglong Cave, a recently discovered Late Pleistocene hominin site in northern Hubei Province, central China. Systematic excavations there have led to the in situ discovery of seven hominin teeth and dozens of stone and bone artifacts. The U-series dates on localized thin flowstone formations bracket the hominin specimens between 81 and 101 ka, currently the most narrow time span for all AMH beyond 45 ka in China, if the assignment of the hominin teeth to modern Homo sapiens holds. Alternatively this study provides further evidence for the early presence of an AMH morphology in China, through either independent evolution of local archaic populations or their assimilation with incoming AMH. Along with recent dating results for hominin samples from Homo erectus to AMH, a new extended and continuous timeline for Chinese hominin fossils is taking shape, which warrants a reconstruction of human evolution, especially the origins of modern humans in eastern Asia.

  5. Taphonomy of fossils from the hominin-bearing deposits at Dikika, Ethiopia.

    PubMed

    Thompson, Jessica C; McPherron, Shannon P; Bobe, René; Reed, Denné; Barr, W Andrew; Wynn, Jonathan G; Marean, Curtis W; Geraads, Denis; Alemseged, Zeresenay

    2015-09-01

    Two fossil specimens from the DIK-55 locality in the Hadar Formation at Dikika, Ethiopia, are contemporaneous with the earliest documented stone tools, and they collectively bear twelve marks interpreted to be characteristic of stone tool butchery damage. An alternative interpretation of the marks has been that they were caused by trampling animals and do not provide evidence of stone tool use or large ungulate exploitation by Australopithecus-grade hominins. Thus, resolving which agents created marks on fossils in deposits from Dikika is an essential step in understanding the ecological and taphonomic contexts of the hominin-bearing deposits in this region and establishing their relevance for investigations of the earliest stone tool use. This paper presents results of microscopic scrutiny of all non-hominin fossils collected from the Hadar Formation at Dikika, including additional fossils from DIK-55, and describes in detail seven assemblages from sieved surface sediment samples. The study is the first taphonomic description of Pliocene fossil assemblages from open-air deposits in Africa that were collected without using only methods that emphasize the selective retention of taxonomically-informative specimens. The sieved assemblages show distinctive differences in faunal representation and taphonomic modifications that suggest they sample a range of depositional environments in the Pliocene Hadar Lake Basin, and have implications for how landscape-based taphonomy can be used to infer past microhabitats. The surface modification data show that no marks on any other fossils resemble in size or shape those on the two specimens from DIK-55 that were interpreted to bear stone tool inflicted damage. A large sample of marks from the sieved collections has characteristics that match modern trampling damage, but these marks are significantly smaller than those on the DIK-55 specimens and have different suites of characteristics. Most are not visible without magnification

  6. Complex Tasks Force Hand Laterality and Technological Behaviour in Naturalistically Housed Chimpanzees: Inferences in Hominin Evolution

    PubMed Central

    Mosquera, M.; Geribàs, N.; Bargalló, A.; Llorente, M.; Riba, D.

    2012-01-01

    Clear hand laterality patterns in humans are widely accepted. However, humans only elicit a significant hand laterality pattern when performing complementary role differentiation (CRD) tasks. Meanwhile, hand laterality in chimpanzees is weaker and controversial. Here we have reevaluated our results on hand laterality in chimpanzees housed in naturalistic environments at Fundació Mona (Spain) and Chimfunshi Wild Orphanage (Zambia). Our results show that the difference between hand laterality in humans and chimpanzees is not as great as once thought. Furthermore, we found a link between hand laterality and task complexity and also an even more interesting connection: CRD tasks elicited not only the hand laterality but also the use of tools. This paper aims to turn attention to the importance of this threefold connection in human evolution: the link between CRD tasks, hand laterality, and tool use, which has important evolutionary implications that may explain the development of complex behaviour in early hominins. PMID:22550466

  7. Carnivore activity in the Sima de los Huesos (Atapuerca, Spain) hominin sample

    NASA Astrophysics Data System (ADS)

    Sala, Nohemi; Arsuaga, Juan Luis; Martínez, Ignacio; Gracia-Téllez, Ana

    2014-08-01

    The Sima de los Huesos (SH) site is the largest accumulation of human remains from the Middle Pleistocene known to date. Studies in the last two decades have proposed different hypotheses to explain carnivore activity in the SH human sample. This study provides new data in order to test these different interpretations, and therefore to understand the role of the carnivores in site formation at SH. Carnivores are usually not the origin of large accumulations of hominin fossils in the Eurasian record. The results show that marks of carnivore activity in the SH sample appear very infrequently, which we interpret as indicating that carnivore activity was very sporadic at the site. This is in stark contrast with previous studies. The comparison of bone modification patterns at SH to actualistic carnivore data allows us to suggest that bears were likely to have been the carnivore responsible for the modification observed on both human and bear fossils.

  8. Experimental perspective on fallback foods and dietary adaptations in early hominins

    PubMed Central

    Scott, Jeremiah E.; McAbee, Kevin R.; Eastman, Meghan M.; Ravosa, Matthew J.

    2014-01-01

    The robust jaws and large, thick-enameled molars of the Plio–Pleistocene hominins Australopithecus and Paranthropus have long been interpreted as adaptations for hard-object feeding. Recent studies of dental microwear indicate that only Paranthropus robustus regularly ate hard items, suggesting that the dentognathic anatomy of other australopiths reflects rare, seasonal exploitation of hard fallback foods. Here, we show that hard-object feeding cannot explain the extreme morphology of Paranthropus boisei. Rather, analysis of long-term dietary plasticity in an animal model suggests year-round reliance on tough foods requiring prolonged postcanine processing in P. boisei. Increased consumption of such items may have marked the earlier transition from Ardipithecus to Australopithecus, with routine hard-object feeding in P. robustus representing a novel behaviour. PMID:24402713

  9. Complex tasks force hand laterality and technological behaviour in naturalistically housed chimpanzees: inferences in hominin evolution.

    PubMed

    Mosquera, M; Geribàs, N; Bargalló, A; Llorente, M; Riba, D

    2012-01-01

    Clear hand laterality patterns in humans are widely accepted. However, humans only elicit a significant hand laterality pattern when performing complementary role differentiation (CRD) tasks. Meanwhile, hand laterality in chimpanzees is weaker and controversial. Here we have reevaluated our results on hand laterality in chimpanzees housed in naturalistic environments at Fundació Mona (Spain) and Chimfunshi Wild Orphanage (Zambia). Our results show that the difference between hand laterality in humans and chimpanzees is not as great as once thought. Furthermore, we found a link between hand laterality and task complexity and also an even more interesting connection: CRD tasks elicited not only the hand laterality but also the use of tools. This paper aims to turn attention to the importance of this threefold connection in human evolution: the link between CRD tasks, hand laterality, and tool use, which has important evolutionary implications that may explain the development of complex behaviour in early hominins.

  10. Experimental perspective on fallback foods and dietary adaptations in early hominins.

    PubMed

    Scott, Jeremiah E; McAbee, Kevin R; Eastman, Meghan M; Ravosa, Matthew J

    2014-01-01

    The robust jaws and large, thick-enameled molars of the Plio-Pleistocene hominins Australopithecus and Paranthropus have long been interpreted as adaptations for hard-object feeding. Recent studies of dental microwear indicate that only Paranthropus robustus regularly ate hard items, suggesting that the dentognathic anatomy of other australopiths reflects rare, seasonal exploitation of hard fallback foods. Here, we show that hard-object feeding cannot explain the extreme morphology of Paranthropus boisei. Rather, analysis of long-term dietary plasticity in an animal model suggests year-round reliance on tough foods requiring prolonged postcanine processing in P. boisei. Increased consumption of such items may have marked the earlier transition from Ardipithecus to Australopithecus, with routine hard-object feeding in P. robustus representing a novel behaviour.

  11. A niche construction approach on the central Netherlands covering the last 220,000 years.

    PubMed

    van den Biggelaar, Don F A M; Kluiving, Sjoerd J

    This paper shows what a niche construction theory (NCT) approach can contribute to the long-term social and environmental history of an area when applied to both sedentary and non-sedentary communities. To understand how communities create and respond to environmental change, hominin presence of the central Netherlands within the last 220,000 years is used as a case study. For this case study we studied the interrelationship between hominins, water and landscape gradients for four periods of interest within this long-term hominin presence. During each of these periods the study area had a specific environmental setting and (possible) traces of hominin presence. These periods cover the (1) Middle to Late Saalian (~220-170 ka), (2) Late Glacial (~14.7-11.7 ka, (3) Mid-Holocene (6000-5400 BP) and (4) Late Holocene (1200-8 BP). This review shows that traces of niche construction behaviour related to water and landscape gradients in the central Netherlands can be shown for both sedentary and non-sedentary communities. Furthermore, in this review it is shown that the transition from inceptive to counteractive change in ecosystem management style in the central Netherlands took place between the Mid- and Late Holocene periods.

  12. The effect of early hominin occlusal morphology on the fracturing of hard food items.

    PubMed

    Berthaume, Michael; Grosse, Ian R; Patel, Nirdesh D; Strait, David S; Wood, Sarah; Richmond, Brian G

    2010-04-01

    Tooth profile plays an important role in interpretations of the functional morphology of extinct species. We tested hypotheses that australopith occlusal morphology influences the fracture force required to crack large, hard food items using a combination of physical testing and finite element analysis (FEA). We performed mechanical experiments simulating both molar and premolar biting using metal replicas of four hominin specimens representing species that differ in occlusal relief (Praeanthropus afarensis, Australopithecus africanus, Paranthropus robustus, and P. boisei). The replicas were inserted into an Instron machine and used to fracture hollow acrylic hemispheres with known material properties. These hemispheres simulate a hard and brittle food item but exhibit far less variability in size and strength than actual nuts or seeds, thereby facilitating interpretations of tooth function. Fracture forces and fracture displacements were measured, and analysis of variance revealed significant differences in fracture force and energy between specimens and tooth types. Complementing the physical testing, a nonlinear contact finite element model was developed to simulate each physical test. Experimental and FEA results showed good correspondence in most cases, and FEA identified stress concentrations consistent with mechanical models predicting that radial/median fractures are important factors in the failure of nut and seed shells. The fracture force data revealed functional similarities between relatively unworn Pr. afarensis and P. robustus teeth, and between relatively unworn A. africanus and heavily worn P. boisei teeth. These results are inconsistent with functional hypotheses, and raise the possibility that the tooth morphology of early hominins and other hard object feeders may not represent adaptations for inducing fractures in large, hard food items, but rather for resisting fractures in the tooth crown. (c) 2010 Wiley-Liss, Inc.

  13. Dynamic similarity predicts gait parameters for Homo floresiensis and the Laetoli hominins.

    PubMed

    Vaughan, Christopher L; Blaszczyk, Maria B

    2008-01-01

    Late in 2004, the skeletal remains of a pygmy-sized hominin recovered from a cave on the Indonesian island of Flores were first documented, with the authors concluding that the "postcranial anatomy [was] consistent with human-like obligate bipedalism" (Brown et al. [2004]: Nature 431:1055-1061). We have assumed that Homo floresiensis, who was estimated to be 18,000-years-old, walked with a gait pattern that was dynamically similar to modern man. The dynamic similarity hypothesis was also applied to the Australopithecines that left their footprints at Laetoli 4-million-years ago. According to this hypothesis, dimensionless gait parameters can be used in combination with known leg length or step length to calculate velocity of bipedal locomotion. We have gathered data on 20 extant modern humans to calculate the standard estimates of error when predicting gait parameters. We predict that the Homo floresiensis specimen walked at a velocity of 1.11 +/- 0.14 m/s. For the Laetoli footprints, the velocity for Track 1 was estimated to be 1.03 +/- 0.12 m/s and for Track 2 to be 1.14 +/- 0.12 m/s. These latter values for Australopithecines are greater than prior analyses, but are in good agreement with more recent work based on evolutionary robotics. Since modern man walks at 1.44 +/- 0.14 m/s, our results suggest that, despite their diminutive size, these ancient hominins were capable of ranging across a wide geographical area.

  14. Early Pleistocene lake formation and hominin origins in the Turkana-Omo rift

    NASA Astrophysics Data System (ADS)

    Lepre, Christopher J.

    2014-10-01

    Prior research has correlated the formation of Plio-Pleistocene lakes in East Africa to global/regional climate changes and interpreted the lacustrine basins as significant settings of hominin evolution. Paleo-Lake Lorenyang from the Turkana-Omo rift is important to these issues, as its marginal deposits contain some of, if not the earliest currently known specimens of Acheulian stone tools and African Homo erectus. Magnetostratigraphic and sedimentological evidence indicates that the oldest preserved paleo-Lake Lorenyang deposits are dated at 2.148-2.128 Ma and derive from the NW Turkana basin, predating those from the Omo basin by ˜100 kyr and the NE Turkana basin by ˜190 kyr. Apparently, the lake expanded asynchronously in the rift, potentially due to a volcano-tectonic influence on the location of drainage networks, depositional slopes, or topographic elevation differences within and between the basins at the time of flooding. The onset of the lake temporally coincides with the eruption of basalt lava flows dated to 2.2-2.0 Ma that blocked the southeast outlet of the Turkana basin. This provides a plausible mechanism for hydrologic closure and lacustrine basin formation through volcano-tectonic impounding. It also points to a non-climatic cause for the initial formation of paleo-Lake Lorenyang at ˜2.14 Ma. First appearances for African H. erectus (˜1.87 Ma) and Acheulian tools (˜1.76 Ma) in the Turkana-Omo rift postdate the lake's initial formation by about 270 kyr and 380 kyr, respectively. Such timing differences contrast with studies that correlate all three to the 400-kyr-eccentricity maximum at 1.8 Ma. Although the Turkana-Omo rift is just one example, it does provide alternative insights to views that link climate, hominin evolution, and lake formation in East Africa.

  15. Modeling the dental development of fossil hominins through the inhibitory cascade

    PubMed Central

    Schroer, Kes; Wood, Bernard

    2015-01-01

    The inhibitory cascade is a mathematical model for interpreting the relative size of the occlusal surfaces of mammalian molars in terms of developmental mechanisms. The cascade is derived from experimental studies of mouse molars developed in culture, and has been tested and applied to the dentitions of rodents, ungulates, carnivores, and platyrrhines. Results from such applications have provided new information regarding the origins of plesiomorphic traits in mammalian clade and how derived morphologies may arise. In this study we apply the inhibitory cascade model to the postcanine dentition of a sample of Old World primates that includes fossil hominins. The results of this study suggest that the inhibitory cascade (i.e. M1 < M2 < M3) describes the relative sizes of the molar occlusal areas of Old World primates and is likely the plesiomorphic condition for this clade. Within that clade, whereas most Old World monkeys have a M1 < M2 < M3 pattern, most apes have a M1 < M2 ≈ M3 pattern. This modified cascade suggests that greater levels of inhibition (or less activation) are acting on the posterior molars of apes, thus facilitating the reduction of M3s within the apes. With the exception of the baboon genus Papio, extant congeners typically share the same molar inhibitory cascade. The differences in the relative size relationships observed in the molar and premolar-molar cascades of the species included in the fossil hominin genus Paranthropus suggest that although large postcanine teeth are a shared derived trait within this genus, the developmental basis for postcanine megadontia may not be the same in these two Paranthropus taxa. Our results show that phenotypic characters such as postcanine megadontia may not reflect common development. PMID:25420453

  16. Viewpoints: diet and dietary adaptations in early hominins: the hard food perspective.

    PubMed

    Strait, David S; Constantino, Paul; Lucas, Peter W; Richmond, Brian G; Spencer, Mark A; Dechow, Paul C; Ross, Callum F; Grosse, Ian R; Wright, Barth W; Wood, Bernard A; Weber, Gerhard W; Wang, Qian; Byron, Craig; Slice, Dennis E; Chalk, Janine; Smith, Amanda L; Smith, Leslie C; Wood, Sarah; Berthaume, Michael; Benazzi, Stefano; Dzialo, Christine; Tamvada, Kelli; Ledogar, Justin A

    2013-07-01

    Recent biomechanical analyses examining the feeding adaptations of early hominins have yielded results consistent with the hypothesis that hard foods exerted a selection pressure that influenced the evolution of australopith morphology. However, this hypothesis appears inconsistent with recent reconstructions of early hominin diet based on dental microwear and stable isotopes. Thus, it is likely that either the diets of some australopiths included a high proportion of foods these taxa were poorly adapted to consume (i.e., foods that they would not have processed efficiently), or that aspects of what we thought we knew about the functional morphology of teeth must be wrong. Evaluation of these possibilities requires a recognition that analyses based on microwear, isotopes, finite element modeling, and enamel chips and cracks each test different types of hypotheses and allow different types of inferences. Microwear and isotopic analyses are best suited to reconstructing broad dietary patterns, but are limited in their ability to falsify specific hypotheses about morphological adaptation. Conversely, finite element analysis is a tool for evaluating the mechanical basis of form-function relationships, but says little about the frequency with which specific behaviors were performed or the particular types of food that were consumed. Enamel chip and crack analyses are means of both reconstructing diet and examining biomechanics. We suggest that current evidence is consistent with the hypothesis that certain derived australopith traits are adaptations for consuming hard foods, but that australopiths had generalized diets that could include high proportions of foods that were both compliant and tough. Copyright © 2013 Wiley Periodicals, Inc.

  17. Geoarchaeological approaches to Palaeolithic surface artefact distributions and hominin landscape use in SW Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Inglis, Robyn; Sinclair, Anthony; Fanning, Patricia; Alsharekh, Abdullah; Bailey, Geoff

    2017-04-01

    The vast majority of Palaeolithic archaeological material in arid and semi-arid regions exists in the form of scatters of stone tools across the surface of present-day landscapes. This is particularly the case in the Saharo-Arabian desert belt, a region vital to understanding the global dispersal of hominins from Africa. These surface artefacts possess little stratigraphic context, but comprise the only record we possess to examine spatial behavioural patterning and landscape use by hominin populations. Interpretation of the observed spatial distribution of artefacts is far from straightforward. Surface artefact distributions result from a complex interplay of varying human behaviours over time. Also, geomorphological processes affect the preservation, exposure and visibility of the artefacts, as well as alter the presence and location of attractive resources. The SURFACE project employs an interdisciplinary approach to understanding the distribution of Palaeolithic artefacts in SW Saudi Arabia. By combining remote sensing, geomorphological fieldwork, archaeological survey and GIS analyses, the project is developing a geomorphological context for the artefacts that guides survey to areas of high archaeological potential, as well as allowing the robust interpretation of the observed artefact distribution in a dynamic landscape in terms of past landscape use. This paper will present the ongoing multi-scalar approaches employed by the project to Palaeolithic landscapes, particularly focussing on the site of Wadi Dabsa, Asir Province, where Lower and Middle Palaeolithic artefacts have been found in association with extensive tufa deposits. Investigation in early 2017 at the site will apply SURFACE's methods to understand the present-day artefact distributions at the exposure, and their relationship to the tufa deposition, as well as their potential to inform on Palaeolithic activity and landscape use at the site.

  18. Homo erectus and Middle Pleistocene hominins: brain size, skull form, and species recognition.

    PubMed

    Rightmire, G Philip

    2013-09-01

    Hominins that differ from Homo erectus, the Neanderthals, and recent humans are known from Middle Pleistocene localities across the Old World. The taxonomic status of these populations has been clouded by controversy. Perhaps the most critical problem has been an incomplete understanding of variation in skull form. Here, both H. erectus and later mid-Pleistocene hominins are the focus of an investigation aimed at clarifying the relationships among brain volume, basicranial dimensions, neurocranial shape, and certain facial characters. Brain size in H. erectus averages about 950 cm(3), while in a series of Middle Pleistocene crania from Africa and Europe, volume is about 1230 cm(3). If encephalization is the primary mechanism operating in the mid-Pleistocene, then diverse aspects of cranial form cannot all be treated as independent variables. Correlation is utilized to examine the associations among measurements for more than 30 H. erectus crania that are reasonably well preserved. A similar approach is used with the Middle Pleistocene sample. Patterns of covariation are compared in order to assess integration. Next, factor analysis is applied to the H. erectus specimens in an attempt to identify modules, tightly integrated traits that can evolve independently. Studies of the variation within H. erectus are followed by direct comparisons with the Middle Pleistocene population. Discriminant functions facilitate the description of intergroup differences. Traits that vary independently from brain volume include anterior frontal broadening, lateral expansion of the parietal vault, elevation of the lambda-inion chord, and rounding of the sagittal contour of the occipital. This finding helps to resolve the problem of species recognition. Neurocranial proportions as well as characters from the cranial base and face can be incorporated into a differential diagnosis for the mid-Pleistocene sample. Evidence presented here supports arguments for speciation in the Middle

  19. Human neutrophil antigen profiles in Banjar, Bugis, Champa, Jawa and Kelantan Malays in Peninsular Malaysia

    PubMed Central

    Manaf, Siti M.; NurWaliyuddin, Hanis Z.A.; Panneerchelvam, Sundararajulu; Zafarina, Zainuddin; Norazmi, Mohd N.; Chambers, Geoffrey K.; Edinur, Hisham A.

    2015-01-01

    Background Human neutrophil antigens (HNA) are polymorphic and immunogenic proteins involved in the pathogenesis of neonatal alloimmune neutropenia, transfusion-related acute lung injury (TRALI) and transfusion-related alloimmune neutropenia. The characterisation of HNA at a population level is important for predicting the risk of alloimmunisation associated with blood transfusion and gestation and for anthropological studies. Materials and methods Blood samples from 192 healthy, unrelated Malays were collected and genotyped using polymerase chain reaction-sequence specific primers (HNA-1, -3, -4) and polymerase chain reaction-restriction fragment length polymorphisms (HNA-5). The group comprised 30 Banjar, 37 Bugis, 51 Champa, 39 Jawa and 35 Kelantan Malays. Results The most common HNA alleles in the Malays studied were HNA-1a (0.641–0.765), -3a (0.676–0.867), -4a (0.943–1.000) and -5a (0.529–0.910). According to principal coordinate plots constructed using HNA allele frequencies, the Malay sub-ethnic groups are closely related and grouped together with other Asian populations. The risks of TRALI or neonatal neutropenia were not increased for subjects with HNA-1, -3 and -4 loci even for donor and recipient or pairs from different Malay sub-ethnic groups. Nonetheless, our estimates showed significantly higher risks of HNA alloimmunisation during pregnancy and transfusion between Malays and other genetically differentiated populations such as Africans and Europeans. Discussion This study reports HNA allele and genotype frequencies for the five Malay sub-ethnic groups living in Peninsular Malaysia for the first time. These Malay sub-ethnic groups show closer genetic relationships with other Asian populations than with Europeans and Africans. The distributions of HNA alleles in other lineages of people living in Malaysia (e.g. Chinese, Indian and Orang Asli) would be an interesting subject for future study. PMID:26057487

  20. Human neutrophil antigen profiles in Banjar, Bugis, Champa, Jawa and Kelantan Malays in Peninsular Malaysia.

    PubMed

    Manaf, Siti M; NurWaliyuddin, Hanis Z A; Panneerchelvam, Sundararajulu; Zafarina, Zainuddin; Norazmi, Mohd N; Chambers, Geoffrey K; Edinur, Hisham A

    2015-10-01

    Human neutrophil antigens (HNA) are polymorphic and immunogenic proteins involved in the pathogenesis of neonatal alloimmune neutropenia, transfusion-related acute lung injury (TRALI) and transfusion-related alloimmune neutropenia. The characterisation of HNA at a population level is important for predicting the risk of alloimmunisation associated with blood transfusion and gestation and for anthropological studies. Blood samples from 192 healthy, unrelated Malays were collected and genotyped using polymerase chain reaction-sequence specific primers (HNA-1, -3, -4) and polymerase chain reaction-restriction fragment length polymorphisms (HNA-5). The group comprised 30 Banjar, 37 Bugis, 51 Champa, 39 Jawa and 35 Kelantan Malays. The most common HNA alleles in the Malays studied were HNA-1a (0.641-0.765), -3a (0.676-0.867), -4a (0.943-1.000) and -5a (0.529-0.910). According to principal coordinate plots constructed using HNA allele frequencies, the Malay sub-ethnic groups are closely related and grouped together with other Asian populations. The risks of TRALI or neonatal neutropenia were not increased for subjects with HNA-1, -3 and -4 loci even for donor and recipient or pairs from different Malay sub-ethnic groups. Nonetheless, our estimates showed significantly higher risks of HNA alloimmunisation during pregnancy and transfusion between Malays and other genetically differentiated populations such as Africans and Europeans. This study reports HNA allele and genotype frequencies for the five Malay sub-ethnic groups living in Peninsular Malaysia for the first time. These Malay sub-ethnic groups show closer genetic relationships with other Asian populations than with Europeans and Africans. The distributions of HNA alleles in other lineages of people living in Malaysia (e.g. Chinese, Indian and Orang Asli) would be an interesting subject for future study.

  1. Variations in size, shape and asymmetries of the third frontal convolution in hominids: paleoneurological implications for hominin evolution and the origin of language.

    PubMed

    Balzeau, Antoine; Gilissen, Emmanuel; Holloway, Ralph L; Prima, Sylvain; Grimaud-Hervé, Dominique

    2014-11-01

    The study of brain structural asymmetries as anatomical substrates of functional asymmetries in extant humans, great apes, and fossil hominins is of major importance in understanding the structural basis of modern human cognition. We propose methods to quantify the variation in size, shape and bilateral asymmetries of the third frontal convolution (or posterior inferior frontal gyrus) among recent modern humans, bonobos and chimpanzees, and fossil hominins using actual and virtual endocasts. These methodological improvements are necessary to extend previous qualitative studies of these features. We demonstrate both an absolute and relative bilateral increase in the size of the third frontal convolution in width and length between Pan species, as well as in hominins. We also observed a global bilateral increase in the size of the third frontal convolution across all species during hominin evolution, but also non-allometric intra-group variations independent of brain size within the fossil samples. Finally, our results show that the commonly accepted leftward asymmetry of Broca's cap is biased by qualitative observation of individual specimens. The trend during hominin evolution seems to be a reduction in size on the left compared with the right side, and also a clearer definition of the area. The third frontal convolution considered as a whole projects more laterally and antero-posteriorly in the right hemisphere. As a result, the left 'Broca's cap' looks more globular and better defined. Our results also suggest that the pattern of brain asymmetries is similar between Pan paniscus and hominins, leaving the gradient of the degree of asymmetry as the only relevant structural parameter. As the anatomical substrate related to brain asymmetry has been present since the appearance of the hominin lineage, it is not possible to prove a direct relationship between the extent of variations in the size, shape, and asymmetries of the third frontal convolution and the origin of

  2. Persistent C3 vegetation accompanied Plio-Pleistocene hominin evolution in the Malawi Rift (Chiwondo Beds, Malawi).

    PubMed

    Lüdecke, Tina; Schrenk, Friedemann; Thiemeyer, Heinrich; Kullmer, Ottmar; Bromage, Timothy G; Sandrock, Oliver; Fiebig, Jens; Mulch, Andreas

    2016-01-01

    The development of East African savannas is crucial for the origin and evolution of early hominins. These ecosystems, however, vary widely in their fraction of woody cover and today range from closed woodland to open grassland savanna. Here, we present the first Plio-Pleistocene long-term carbon isotope (δ(13)C) record from pedogenic carbonate and Suidae teeth in the southern East African Rift (EAR). These δ(13)C data from the Chiwondo and Chitimwe Beds (Karonga Basin, Northern Malawi) represent a southern hemisphere record in the EAR, a key region for reconstructing vegetation patterns in today's Zambezian Savanna, and permit correlation with data on the evolution and migration of early hominins in today's Somali-Masai Endemic Zone. The sediments along the northwestern shore of Lake Malawi contain fossils attributed to Homo rudolfensis and Paranthropus boisei. The associated hominin localities (Uraha, Malema) are situated between the well-known hominin bearing sites of the Somali-Masai Endemic Zone in the Eastern Rift and the Highveld Grassland in southern Africa, and fill an important geographical gap for hominin research. Persistent δ(13)C values around -9‰ from pedogenic carbonate and suid enamel covering the last ∼4.3 Ma indicate a C3-dominated closed environment with regional patches of C4-grasslands in the Karonga Basin. The overall fraction of woody cover of 60-70% reflects significantly higher canopy density in the Malawi Rift than the Eastern Rift through time. The discrepancy between the two savanna types originated in the Late Pliocene, when the Somali-Masai ecosystem started to show increasing evidence for open, C4-dominated landscapes. Based on the Malawi δ(13)C data, the evolution of savanna ecosystems in Eastern Africa followed different patterns along the north-south extent of the EAR. The appearance of C4-grasses is considered a driver of evolutionary faunal shifts, but despite the difference of ecosystem evolution in the north, similar

  3. Landscapes and their relation to hominin habitats: case studies from Australopithecus sites in eastern and southern Africa.

    PubMed

    Reynolds, Sally C; Bailey, Geoff N; King, Geoffrey C P

    2011-03-01

    We examine the links between geomorphological processes, specific landscape features, surface water drainage, and the creation of suitable habitats for hominins. The existence of mosaic (i.e., heterogeneous) habitats within hominin site landscape reconstructions is typically explained using models of the riverine and gallery forest settings, or the pan or lake setting. We propose a different model: the Tectonic Landscape Model (TLM), where tectonic faulting and volcanism disrupts existing pan or river settings at small-scales (∼10-25 km). Our model encompasses the interpretation of the landscape features, the role of tectonics in creating these landscapes, and the implications for hominins. In particular, the model explains the underlying mechanism for the creation and maintenance of heterogeneous habitats in regions of active tectonics. We illustrate how areas with faulting and disturbed drainage patterns would have been attractive habitats for hominins, such as Australopithecus, and other fauna. Wetland areas are an important characteristic of surface water disturbance by fault activity; therefore we examine the tectonically-controlled Okavango Delta (Botswana) and the Nylsvley wetland (South Africa) as modern examples of how tectonics in a riverine setting significantly enhance the faunal and floral biodiversity. While tectonic landscapes may not have been the only type of attractive habitats to hominins, we propose a suite of landscape, faunal, and floral indicators, which when recovered together suggest that site environments may have been influenced by tectonic and/or volcanic activity while hominins were present. For the fossil sites, we interpret the faulting and landscapes around australopithecine-bearing sites of the Middle Awash (Ethiopia) and Makapansgat, Taung, and Sterkfontein (South Africa) to illustrate these relationships between landscape features and surface water bodies. Exploitation of tectonically active landscapes may explain why the

  4. Evidence for chronic omega-3 fatty acids and ascorbic acid deficiency in Palaeolithic hominins in Europe at the emergence of cannibalism

    NASA Astrophysics Data System (ADS)

    Guil-Guerrero, J. L.

    2017-02-01

    At the Middle-Upper Palaeolithic (M/UP) transition in Western Europe, hominins depended mostly on terrestrial mammals for subsistence, being pointed out that reliance on reindeer (Rangifer tarandus) would have promoted declines in human population densities during that period. Food-composition tables have been compiled for hominins at the M/UP transition, listing protein, fat, energy, different omega-3 fatty acids and ascorbic acid concentrations. These data were used to compute the regular relations between fatty and lean tissues of the main hunted food-animals to meet hominin energy needs. Then, with daily protein intake considered critical, the optimal contribution of the different omega-3 fatty acids from different hunted species to hominin diets were computed. Several faunal assemblages from different human sites at different M/UP periods were used to assess the overall daily intake of the various omega-3 fatty acid classes. The results of the calculations made in this work are quite clear; hominins at the M/UP transition had a deficit of both omega-3 fatty acids and ascorbic acid. Data on human organs summarized here are also conclusive: these contain such nutrients in amounts much higher than reached in the corresponding mammal organs consumed, and thus could have been alternative sources of those nutrients for Palaeolithic hominins. Therefore, nutritional cannibalism detected at such times could have had the function of alleviating these deficits. The evolutionary advantages gained by the consumption of the various omega-3 fatty acids of human origin are also discussed.

  5. Niche Partitioning in Sympatric Gorilla and Pan from Cameroon: Implications for Life History Strategies and for Reconstructing the Evolution of Hominin Life History

    PubMed Central

    Macho, Gabriele A.; Lee-Thorp, Julia A.

    2014-01-01

    Factors influencing the hominoid life histories are poorly understood, and little is known about how ecological conditions modulate the pace of their development. Yet our limited understanding of these interactions underpins life history interpretations in extinct hominins. Here we determined the synchronisation of dental mineralization/eruption with brain size in a 20th century museum collection of sympatric Gorilla gorilla and Pan troglodytes from Central Cameroon. Using δ13C and δ15N of individuals’ hair, we assessed whether and how differences in diet and habitat use may have impacted on ape development. The results show that, overall, gorilla hair δ13C and δ15N values are more variable than those of chimpanzees, and that gorillas are consistently lower in δ13C and δ15N compared to chimpanzees. Within a restricted, isotopically-constrained area, gorilla brain development appears delayed relative to dental mineralization/eruption [or dental development is accelerated relative to brains]: only about 87.8% of adult brain size is attained by the time first permanent molars come into occlusion, whereas it is 92.3% in chimpanzees. Even when M1s are already in full functional occlusion, gorilla brains lag behind those of chimpanzee (91% versus 96.4%), relative to tooth development. Both bootstrap analyses and stable isotope results confirm that these results are unlikely due to sampling error. Rather, δ15N values imply that gorillas are not fully weaned (physiologically mature) until well after M1 are in full functional occlusion. In chimpanzees the transition from infant to adult feeding appears (a) more gradual and (b) earlier relative to somatic development. Taken together, the findings are consistent with life history theory that predicts delayed development when non-density dependent mortality is low, i.e. in closed habitats, and with the “risk aversion” hypothesis for frugivorous species as a means to avert starvation. Furthermore, the results

  6. A 400,000-year-old mitochondrial genome questions phylogenetic relationships amongst archaic hominins: using the latest advances in ancient genomics, the mitochondrial genome sequence of a 400,000-year-old hominin has been deciphered.

    PubMed

    Orlando, Ludovic

    2014-06-01

    By combining state-of-the-art approaches in ancient genomics, Meyer and co-workers have reconstructed the mitochondrial sequence of an archaic hominin that lived at Sierra de Atapuerca, Spain about 400,000 years ago. This achievement follows recent advances in molecular anthropology that delivered the genome sequence of younger archaic hominins, such as Neanderthals and Denisovans. Molecular phylogenetic reconstructions placed the Atapuercan as a sister group to Denisovans, although its morphology suggested closer affinities with Neanderthals. In addition to possibly challenging our interpretation of the fossil record, this study confirms that genomic information can be recovered from extremely damaged DNA molecules, even in the presence of significant levels of human contamination. Together with the recent characterization of a 700,000-year-old horse genome, this study opens the Middle Pleistocene to genomics, thereby extending the scope of ancient DNA to the last million years. © 2014 WILEY Periodicals, Inc.

  7. On the tool use behavior of the bonobo-chimpanzee last common ancestor, and the origins of hominine stone tool use.

    PubMed

    Haslam, Michael

    2014-10-01

    The last common ancestor (LCA) shared by chimpanzees (Pan troglodytes) and bonobos (P. paniscus) was an Early Pleistocene African ape, which, based on the behavior of modern chimpanzees, may be assumed to be a tool-using animal. However, the character of tool use in the Pan lineage prior to the 20th century is largely unknown. Here, I use available data on wild bonobo tool use and emerging molecular estimates of demography during Pan evolution to hypothesise the plausible tool use behavior of the bonobo-chimpanzee LCA (or "Pancestor") at the start of the Pleistocene, over 2 million years ago. This method indicates that the common ancestor of living Pan apes likely used plant tools for probing, sponging, and display, but it did not use stone tools. Instead, stone tool use appears to have been independently invented by Western African chimpanzees (P. t. verus) during the Middle Pleistocene in the region of modern Liberia-Ivory Coast-Guinea, possibly as recently as 200,000-150,000 years ago. If this is the case, then the LCA of humans and chimpanzees likely also did not use stone tools, and this trait probably first emerged among hominins in Pliocene East Africa. This review also suggests that the consistently higher population sizes of Central African chimpanzees (P. t. troglodytes) over the past million years may have contributed to the increased complexity of wild tool use seen in this sub-species today.

  8. An inconspicuous, conspicuous new species of Asian pipesnake, genus Cylindrophis (Reptilia: Squamata: Cylindrophiidae), from the south coast of Jawa Tengah, Java, Indonesia, and an overview of the tangled taxonomic history of C. ruffus (Laurenti, 1768).

    PubMed

    Kieckbusch, Max; Mecke, Sven; Hartmann, Lukas; Ehrmantraut, Lisa; O'shea, Mark; Kaiser, Hinrich

    2016-03-20

    We describe a new species of Cylindrophis currently known only from Grabag, Purworejo Regency, Jawa Tengah Pro-vince (Central Java), Java, Indonesia. Cylindrophis subocularis sp. nov. can be distinguished from all congeners by the presence of a single, eponymous subocular scale between the 3rd and 4th or 4th and 5th supralabial, preventing contact between the 4th or 5th supralabial and the orbit, and by having the prefrontal in narrow contact with or separated from the orbit. We preface our description with a detailed account of the tangled taxonomic history of the similar and putatively wide-ranging species C. ruffus, which leads us to (1) remove the name Scytale scheuchzeri from the synonymy of C. ruffus, (2) list the taxon C. rufa var. javanica as species inquirenda, and (3) synonymize C. mirzae with C. ruffus. We provide additional evidence to confirm that the type locality of C. ruffus is Java. Cylindrophis subocularis sp. nov. is the second species of Asian pipesnake from Java.

  9. Identification of a new hominin bone from Denisova Cave, Siberia using collagen fingerprinting and mitochondrial DNA analysis

    NASA Astrophysics Data System (ADS)

    Brown, Samantha; Higham, Thomas; Slon, Viviane; Pääbo, Svante; Meyer, Matthias; Douka, Katerina; Brock, Fiona; Comeskey, Daniel; Procopio, Noemi; Shunkov, Michael; Derevianko, Anatoly; Buckley, Michael

    2016-03-01

    DNA sequencing has revolutionised our understanding of archaic humans during the Middle and Upper Palaeolithic. Unfortunately, while many Palaeolithic sites contain large numbers of bones, the majority of these lack the diagnostic features necessary for traditional morphological identification. As a result the recovery of Pleistocene-age human remains is extremely rare. To circumvent this problem we have applied a method of collagen fingerprinting to more than 2000 fragmented bones from the site of Denisova Cave, Russia, in order to facilitate the discovery of human remains. As a result of our analysis a single hominin bone (Denisova 11) was identified, supported through in-depth peptide sequencing analysis, and found to carry mitochondrial DNA of the Neandertal type. Subsequent radiocarbon dating revealed the bone to be >50,000 years old. Here we demonstrate the huge potential collagen fingerprinting has for identifying hominin remains in highly fragmentary archaeological assemblages, improving the resources available for wider studies into human evolution.

  10. Identification of a new hominin bone from Denisova Cave, Siberia using collagen fingerprinting and mitochondrial DNA analysis

    PubMed Central

    Brown, Samantha; Higham, Thomas; Slon, Viviane; Pääbo, Svante; Meyer, Matthias; Douka, Katerina; Brock, Fiona; Comeskey, Daniel; Procopio, Noemi; Shunkov, Michael; Derevianko, Anatoly; Buckley, Michael

    2016-01-01

    DNA sequencing has revolutionised our understanding of archaic humans during the Middle and Upper Palaeolithic. Unfortunately, while many Palaeolithic sites contain large numbers of bones, the majority of these lack the diagnostic features necessary for traditional morphological identification. As a result the recovery of Pleistocene-age human remains is extremely rare. To circumvent this problem we have applied a method of collagen fingerprinting to more than 2000 fragmented bones from the site of Denisova Cave, Russia, in order to facilitate the discovery of human remains. As a result of our analysis a single hominin bone (Denisova 11) was identified, supported through in-depth peptide sequencing analysis, and found to carry mitochondrial DNA of the Neandertal type. Subsequent radiocarbon dating revealed the bone to be >50,000 years old. Here we demonstrate the huge potential collagen fingerprinting has for identifying hominin remains in highly fragmentary archaeological assemblages, improving the resources available for wider studies into human evolution. PMID:27020421

  11. Identification of a new hominin bone from Denisova Cave, Siberia using collagen fingerprinting and mitochondrial DNA analysis.

    PubMed

    Brown, Samantha; Higham, Thomas; Slon, Viviane; Pääbo, Svante; Meyer, Matthias; Douka, Katerina; Brock, Fiona; Comeskey, Daniel; Procopio, Noemi; Shunkov, Michael; Derevianko, Anatoly; Buckley, Michael

    2016-03-29

    DNA sequencing has revolutionised our understanding of archaic humans during the Middle and Upper Palaeolithic. Unfortunately, while many Palaeolithic sites contain large numbers of bones, the majority of these lack the diagnostic features necessary for traditional morphological identification. As a result the recovery of Pleistocene-age human remains is extremely rare. To circumvent this problem we have applied a method of collagen fingerprinting to more than 2000 fragmented bones from the site of Denisova Cave, Russia, in order to facilitate the discovery of human remains. As a result of our analysis a single hominin bone (Denisova 11) was identified, supported through in-depth peptide sequencing analysis, and found to carry mitochondrial DNA of the Neandertal type. Subsequent radiocarbon dating revealed the bone to be >50,000 years old. Here we demonstrate the huge potential collagen fingerprinting has for identifying hominin remains in highly fragmentary archaeological assemblages, improving the resources available for wider studies into human evolution.

  12. The mammalian fauna associated with an archaic hominin skullcap and later Acheulean artifacts at Elandsfontein, Western Cape Province, South Africa.

    PubMed

    Klein, Richard G; Avery, Graham; Cruz-Uribe, Kathryn; Steele, Teresa E

    2007-02-01

    The Elandsfontein site, Western Cape Province, South Africa, is well known for an archaic hominin skullcap associated with later Acheulean artifacts. The site has also provided nearly 13,000 mammalian bones that can be identified to skeletal part and taxon. The assemblage derives from 49 species, 15 of which have no historic descendants. Comparisons to radiometrically dated faunas in eastern Africa indicate an age between 1 million and 600 thousand years ago. Unique features of the fauna, including the late occurrence of a dirk-toothed cat and a sivathere, may reflect its geographic origin in a region that was notable historically for its distinctive climate and high degree of biotic endemism. Together, taxonomic composition, geomorphic setting, and pollen extracted from coprolites indicate the proximity of a large marsh or pond, maintained by a higher water table. The small average size of the black-backed jackals implies relatively mild temperatures. The sum of the evidence places bone accumulation during one of the mid-Pleistocene interglacials that were longer and cooler than later ones, including the Holocene. The geomorphic context of the fauna presents no evidence for catastrophe, and most deaths probably resulted from attritional factors that disproportionately killed the young and old. However, only the dental-age profile of long-horned buffalo supports this directly. Field collection methods biased skeletal-part representation, but originally, it probably resembled the pattern in the younger, marsh-edge Acheulean occurrence at Duinefontein 2, 45 km to the south. Excavation there exposed multiple vertebral spreads, which probably mark carcasses from which hominins or large carnivores removed the meatier elements. Bone damage at both sites suggests that, despite abundant artifacts, hominins were much less important than carnivores in the bone accumulation. Together with limited observations from other sites, Elandsfontein and Duinefontein provisionally

  13. Where are inion and endinion? Variations of the exo- and endocranial morphology of the occipital bone during hominin evolution.

    PubMed

    Balzeau, Antoine; Grimaud-Hervé, Dominique; Gilissen, Emmanuel

    2011-10-01

    The occipital bone is frequently investigated in paleoanthropological studies because it has several features that help to differentiate various fossil hominin species. Among these features is the separation between inion and endinion, which has been proposed to be an autapomorphic trait in (Asian) Homo erectus. Methodologies are developed here to quantify for the first time the location of these anatomical points, and to interpret their variation due to the complex interactions between exocranial and endocranial size and shape of the occipital and nuchal planes, as well as the occipital lobes and cerebellum. On the basis of our analysis, neither 'the separation between inion and endinion' nor 'endinion below inion' can be considered as an autapomorphic trait in H. erectus, since this feature is a condition shared by extant African great apes and fossil hominins. Moreover, our results show that the exo- and endocranial anatomy of the occipital bone differs between hominins (except Paranthropus boisei specimens and KNM-ER 1805) and great apes. For example, chimpanzees and bonobos are characterized by a very high position of inion and their occipital bone shows an antero-posterior compression. However, these features are partly correlated with their small size when compared with hominins. Asian H. erectus specimens have a thick occipital torus, but do not differ from other robust specimens, neither in this feature nor in the analysed exo- and endocranial proportions of the occipital bone. Finally, the apparent brain size reduction during the Late Pleistocene and variation between the sexes in anatomically modern humans (AMH) reflect that specimens with smaller brains have a relatively larger posterior height of the cerebellum. However, this trend is not the sole explanation for the 'vertical shift' of endinion above inion that appears occasionally and exclusively in AMH.

  14. Environments and hominin activities across the FLK Peninsula during Zinjanthropus times (1.84 Ma), Olduvai Gorge, Tanzania.

    PubMed

    Blumenschine, Robert J; Stanistreet, Ian G; Njau, Jackson K; Bamford, Marion K; Masao, Fidelis T; Albert, Rosa M; Stollhofen, Harald; Andrews, Peter; Prassack, Kari A; McHenry, Lindsay J; Fernández-Jalvo, Yolanda; Camilli, Eileen L; Ebert, James I

    2012-08-01

    We establish through 13 excavations the landscape context and nature of hominin activities across the Zinjanthropus land surface from which the Leakeys recovered the FLK 22 and FLK NN 1 paleoanthropological assemblages. The land surface was created by fluvial incision of the eastern margin of paleo-Lake Olduvai following a major lake withdrawal. Erosion was uneven, leaving a peninsula bounded by a river channel, the FLK Fault, and a freshwater wetland. This FLK Peninsula supported groves of trees that attracted hominins and carnivores, and that preserved the dense concentrations of carcass remains and stone tools they left behind, including those at FLK 22. Some carcasses appear to have been acquired at the ecotone of the Peninsula and Wetland, where another dense artifact and bone assemblage accumulated. A lesser topographic high at the edge of a Typha marsh in the Wetland was the site of FLK NN 1 and a scatter of large stone tools used possibly for rootstock processing. Our landscape reconstruction delimits the vegetation mosaic indicated by previous work and provides a topographical explanation for the existence of FLK 22 and FLK NN 1. Both are unexpected if the FLK area was the flat, featureless lake margin terrain typical of lake basins similar to paleo-Olduvai. The results show that the Leakeys' sites were not isolated occupation floors but rather parts of a land surface utilized intensively by hominins. Although commonly considered to have been home bases, their likely high predation risk, evidenced by large carnivore feeding traces and the remains of four hominin individuals, suggests visits to them were brief and limited to feeding. Finally, stratigraphic observations confirm that FLK NN 3 accumulated on an older land surface, refuting the hypothesis that the OH 8 foot found there is the same individual as the OH 35 leg from FLK 22.

  15. Fire Usage and Ancient Hominin Detoxification Genes: Protective Ancestral Variants Dominate While Additional Derived Risk Variants Appear in Modern Humans.

    PubMed

    Aarts, Jac M M J G; Alink, Gerrit M; Scherjon, Fulco; MacDonald, Katharine; Smith, Alison C; Nijveen, Harm; Roebroeks, Wil

    Studies of the defence capacity of ancient hominins against toxic substances may contribute importantly to the reconstruction of their niche, including their diets and use of fire. Fire usage implies frequent exposure to hazardous compounds from smoke and heated food, known to affect general health and fertility, probably resulting in genetic selection for improved detoxification. To investigate whether such genetic selection occurred, we investigated the alleles in Neanderthals, Denisovans and modern humans at gene polymorphisms well-known to be relevant from modern human epidemiological studies of habitual tobacco smoke exposure and mechanistic evidence. We compared these with the alleles in chimpanzees and gorillas. Neanderthal and Denisovan hominins predominantly possess gene variants conferring increased resistance to these toxic compounds. Surprisingly, we observed the same in chimpanzees and gorillas, implying that less efficient variants are derived and mainly evolved in modern humans. Less efficient variants are observable from the first early Upper Palaeolithic hunter-gatherers onwards. While not clarifying the deep history of fire use, our results highlight the long-term stability of the genes under consideration despite major changes in the hominin dietary niche. Specifically for detoxification gene variants characterised as deleterious by epidemiological studies, our results confirm the predominantly recent appearance reported for deleterious human gene variants, suggesting substantial impact of recent human population history, including pre-Holocene expansions.

  16. The Jaramillo Bottleneck for Migration of Hominins with Megaherbivores Into Europe via the Danube-Po Gateway

    NASA Astrophysics Data System (ADS)

    Muttoni, G.; Kent, D. V.; Scardia, G.

    2015-12-01

    Based on ongoing magnetostratigraphic work and updated critical reviews of sites bearing hominin remains and/or tools from greater Europe, including the Balkans and Greece, we maintain that the only compelling evidence of hominin presence in these regions was after the Jaramillo subchron (0.99 Ma), at about the time of the climatic late Early Pleistocene revolution (EPR) and the onset of enhanced glacial/interglacial activity from MIS 22 onward. Europe may have become initially populated during the EPR when, possibly for the first time in the Pleistocene, vast and exploitable ecosystems were generated along the Danube-Po Gateway in the Balkan peninsula and northern Italy. These newly formed settings, characterized by low-lands with open grasslands and reduced woody cover during glacial/interglacial transitions, represented the closest analogues to the savanna environment to which several large mammals linked with hominins in a common food web were adapted and could use as a migratory corridor. We acknowledge that lack of evidence may not be a compelling argument, but the absence of the Jaramillo and out-of-sequence cosmogenic nuclide dates with wide error margins in key sections preclude the use of such evidence to substantiate the presence of humans (and presumably associated biostratigraphic markers) prior to the Jaramillo, and thus logically deny applying such conclusions to other systems.

  17. Fire Usage and Ancient Hominin Detoxification Genes: Protective Ancestral Variants Dominate While Additional Derived Risk Variants Appear in Modern Humans

    PubMed Central

    Alink, Gerrit M.; Scherjon, Fulco; MacDonald, Katharine; Smith, Alison C.; Nijveen, Harm; Roebroeks, Wil

    2016-01-01

    Studies of the defence capacity of ancient hominins against toxic substances may contribute importantly to the reconstruction of their niche, including their diets and use of fire. Fire usage implies frequent exposure to hazardous compounds from smoke and heated food, known to affect general health and fertility, probably resulting in genetic selection for improved detoxification. To investigate whether such genetic selection occurred, we investigated the alleles in Neanderthals, Denisovans and modern humans at gene polymorphisms well-known to be relevant from modern human epidemiological studies of habitual tobacco smoke exposure and mechanistic evidence. We compared these with the alleles in chimpanzees and gorillas. Neanderthal and Denisovan hominins predominantly possess gene variants conferring increased resistance to these toxic compounds. Surprisingly, we observed the same in chimpanzees and gorillas, implying that less efficient variants are derived and mainly evolved in modern humans. Less efficient variants are observable from the first early Upper Palaeolithic hunter-gatherers onwards. While not clarifying the deep history of fire use, our results highlight the long-term stability of the genes under consideration despite major changes in the hominin dietary niche. Specifically for detoxification gene variants characterised as deleterious by epidemiological studies, our results confirm the predominantly recent appearance reported for deleterious human gene variants, suggesting substantial impact of recent human population history, including pre-Holocene expansions. PMID:27655273

  18. Cross-comparison of the genome sequences from human, chimpanzee, Neanderthal and a Denisovan hominin identifies novel potentially compensated mutations.

    PubMed

    Zhang, Guojie; Pei, Zhang; Ball, Edward V; Mort, Matthew; Kehrer-Sawatzki, Hildegard; Cooper, David N

    2011-07-01

    The recent publication of the draft genome sequences of the Neanderthal and a ∼50,000-year-old archaic hominin from Denisova Cave in southern Siberia has ushered in a new age in molecular archaeology. We previously cross-compared the human, chimpanzee and Neanderthal genome sequences with respect to a set of disease-causing/disease-associated missense and regulatory mutations (Human Gene Mutation Database) and succeeded in identifying genetic variants which, although apparently pathogenic in humans, may represent a 'compensated' wild-type state in at least one of the other two species. Here, in an attempt to identify further 'potentially compensated mutations' (PCMs) of interest, we have compared our dataset of disease-causing/disease-associated mutations with their corresponding nucleotide positions in the Denisovan hominin, Neanderthal and chimpanzee genomes. Of the 15 human putatively disease-causing mutations that were found to be compensated in chimpanzee, Denisovan or Neanderthal, only a solitary F5 variant (Val1736Met) was specific to the Denisovan. In humans, this missense mutation is associated with activated protein C resistance and an increased risk of thromboembolism and recurrent miscarriage. It is unclear at this juncture whether this variant was indeed a PCM in the Denisovan or whether it could instead have been associated with disease in this ancient hominin.

  19. Bovid mortality profiles in paleoecological context falsify hypotheses of endurance running-hunting and passive scavenging by early Pleistocene hominins

    NASA Astrophysics Data System (ADS)

    Bunn, Henry T.; Pickering, Travis Rayne

    2010-11-01

    The world's first archaeological traces from 2.6 million years ago (Ma) at Gona, in Ethiopia, include sharp-edged cutting tools and cut-marked animal bones, which indicate consumption of skeletal muscle by early hominin butchers. From that point, evidence of hominin meat-eating becomes increasingly more common throughout the Pleistocene archaeological record. Thus, the substantive debate about hominin meat-eating now centers on mode(s) of carcass resource acquisition. Two prominent hypotheses suggest, alternatively, (1) that early Homo hunted ungulate prey by running them to physiological failure and then dispatching them, or (2) that early Homo was relegated to passively scavenging carcass residues abandoned by carnivore predators. Various paleontologically testable predictions can be formulated for both hypotheses. Here we test four predictions concerning age-frequency distributions for bovids that contributed carcass remains to the 1.8 Ma. old FLK 22 Zinjanthropus (FLK Zinj, Olduvai Gorge, Tanzania) fauna, which zooarchaeological and taphonomic data indicate was formed predominantly by early Homo. In all but one case, the bovid mortality data from FLK Zinj violate test predictions of the endurance running-hunting and passive scavenging hypotheses. When combined with other taphonomic data, these results falsify both hypotheses, and lead to the hypothesis that early Homo operated successfully as an ambush predator.

  20. Fine resolution of early hominin time, Beds I and II, Olduvai Gorge, Tanzania.

    PubMed

    Stanistreet, Ian G

    2012-08-01

    Reconstructing paleoenvironments and landscapes within lake-centered, hominin-yielding basinal sequences requires a resolution of time-rock units finer than but complementary to that provided by the present tephrostratigraphy. Although indispensable in providing an absolute time frame at Olduvai, the average 15,000-20,000 year intervals between successive tuff units lack the time resolution to construct a sufficiently contemporary paleolandscape within sedimentary intervals away from the interleaved tuffs. Such control is essential to construct valid paleogeographies in which to contextualize contemporaneous paleoanthropological sites and the traces of hominin land use they contain. Within Beds I and II of the Olduvai Basin a Sequence Stratigraphic analysis has achieved a relative time framework in which time-rock units, "lake-parasequences," each generated by a major advance and withdrawal of the lake system, are recognizable for average periods of about 4000 years duration. Within each of these time slices at least two paleogeographic landscapes are identifiable, reducing the time constraints of an individual landscape reconstruction to a few thousand years. Within the sedimentary succession both highly incised and less incised unconformities are identifiable to provide sequence boundaries. Within each sequence the higher frequency lake-parasequences can be identified by (1) a disconformable base, (2) accretion of sediment during lake transgression and at maximum, (3) a disconformable top caused by lake withdrawal, and (4) a soil profile generated beneath that disconformable land surface. Individual lake-parasequences can be recognized in lake marginal and fan settings, and their imprint can also be seen in the lake setting where, for example, maximum flooding might be marked by a layer of dolomite. Lower Bed II parasequences represent time intervals of <5000 years, while parasequential periods between Tuffs IB and IC in Bed I are <4300 years. Analogous Holocene

  1. Hominin stature, body mass, and walking speed estimates based on 1.5 million-year-old fossil footprints at Ileret, Kenya.

    PubMed

    Dingwall, Heather L; Hatala, Kevin G; Wunderlich, Roshna E; Richmond, Brian G

    2013-06-01

    The early Pleistocene marks a period of major transition in hominin body form, including increases in body mass and stature relative to earlier hominins. However, because complete postcranial fossils with reliable taxonomic attributions are rare, efforts to estimate hominin mass and stature are complicated by the frequent albeit necessary use of isolated, and often fragmentary, skeletal elements. The recent discovery of 1.52 million year old hominin footprints from multiple horizons in Ileret, Kenya, provides new data on the complete foot size of early Pleistocene hominins as well as stride lengths and other characteristics of their gaits. This study reports the results of controlled experiments with habitually unshod Daasanach adults from Ileret to examine the relationships between stride length and speed, and also those between footprint size, body mass, and stature. Based on significant relationships among these variables, we estimate travel speeds ranging between 0.45 m/s and 2.2 m/s from the fossil hominin footprint trails at Ileret. The fossil footprints of seven individuals show evidence of heavy (mean = 50.0 kg; range: 41.5-60.3 kg) and tall individuals (mean = 169.5 cm; range: 152.6-185.8 cm), suggesting that these prints were most likely made by Homo erectus and/or male Paranthropus boisei. The large sizes of these footprints provide strong evidence that hominin body size increased during the early Pleistocene.

  2. Hominin reactions to herbivore distribution in the Lower Palaeolithic of the Southern Levant

    NASA Astrophysics Data System (ADS)

    Devès, Maud; Sturdy, Derek; Godet, Nan; King, Geoffrey C. P.; Bailey, Geoffrey N.

    2014-07-01

    We explore the relationship between the edaphic potential of soils and the mineral properties of the underlying geology as a means of mapping the differential productivity of different areas of the Pleistocene landscape for large herbivores. These factors strongly control the health of grazing animals irrespective of the particular types of vegetation growing on them, but they have generally been neglected in palaeoanthropological studies in favour of a more general emphasis on water and vegetation, which provide an incomplete picture. Taking the Carmel-Galilee-Golan region as an example, we show how an understanding of edaphic potential provides insight into how animals might have exploited the environment. In order to simplify the analysis, we concentrate on the Lower Palaeolithic period and the very large animals that dominate the archaeofaunal assemblages of this period. Topography and the ability of soils to retain water also contribute to the differential productivity and accessibility of different regions and to patterns of seasonal movements of the animals, which are essential to ensure a supply of healthy fodder throughout the year, especially for large animals such as elephants, which require substantial regions of good grazing and browsing. Other animals migrating in groups have similar needs. The complex topography of the Southern Levant with frequent sudden and severe changes in gradient, and a wide variety of landforms including rocky outcrops, cliffs, gorges, and ridges, places major limits on these patterns of seasonal movements. We develop methods of mapping these variables, based on the geology and our substantial field experience, in order to create a framework of landscape variation that can be compared with the locations and contents of archaeological sites to suggest ways in which early hominins used the variable features of the landscape to target animal prey, and extend the analysis to the consideration of smaller mammals that were exploited

  3. Contemporary flowstone development links early hominin bearing cave deposits in South Africa

    NASA Astrophysics Data System (ADS)

    Pickering, Robyn; Kramers, Jan D.; Hancox, Philip John; de Ruiter, Darryl J.; Woodhead, Jon D.

    2011-06-01

    The Cradle of Humankind cave sites in South Africa preserve fossil evidence of four early hominin taxa: Australopithecus africanus, Australopithecus sediba, Paranthropus robustus and early Homo. In order to integrate this record into a pan-African scenario of human evolutionary history it is critical to have reliable dates and temporal ranges for the southern African hominins. In the past a lack of precise and accurate chronological data has prevented the evaluation of the temporal relationships between the various sites. Here we report new uranium-lead (U-Pb) radiometric ages obtained from sheets of calcium carbonate flowstone inter-bedded between clastic cave sediments at the site of Swartkrans, providing bracketing ages for the fossiliferous deposits. The fossil bearing units of Swartkrans, specifically the Hanging Remnant and Lower Bank of Member 1, are underlain by flowstone layers dated to 2.25 ± 0.05 Ma and 2.25 ± 0.08 Ma and capped by layers of 1.8 ± 0.01 Ma and 1.7 ± 0.07 Ma. The age bracket of the Member 1 deposits is therefore between 2.31 and 1.64 Ma. However, by combining the U-Pb with biostratigraphic data we suggest that this can be narrowed down to between 1.9 and 1.8 Ma. These data can be compared with other recently dated sites and a radiometrically dated U-Pb age sequence formed: Sterkfontein Member 4, Swartkrans Member 1, Malapa, and Cooper's D. From this new U-Pb dataset, a pattern of contemporary flowstone development emerges, with different caves recording the same flowstone-forming event. Specifically overlapping flowstone formation takes place at Swartkrans and Sterkfontein at ~ 2.29 Ma and ~ 1.77 Ma, and at Sterkfontein and Malapa at ˜ 2.02 Ma. This suggests a regional control over the nature and timing of speleothem development in cave deposits and these flowstone layers could assist in future correlation, both internal to specific deposits and regionally between sites.

  4. Alternating high and low climate variability: The context of natural selection and speciation in Plio-Pleistocene hominin evolution.

    PubMed

    Potts, Richard; Faith, J Tyler

    2015-10-01

    Interaction of orbital insolation cycles defines a predictive model of alternating phases of high- and low-climate variability for tropical East Africa over the past 5 million years. This model, which is described in terms of climate variability stages, implies repeated increases in landscape/resource instability and intervening periods of stability in East Africa. It predicts eight prolonged (>192 kyr) eras of intensified habitat instability (high variability stages) in which hominin evolutionary innovations are likely to have occurred, potentially by variability selection. The prediction that repeated shifts toward high climate variability affected paleoenvironments and evolution is tested in three ways. In the first test, deep-sea records of northeast African terrigenous dust flux (Sites 721/722) and eastern Mediterranean sapropels (Site 967A) show increased and decreased variability in concert with predicted shifts in climate variability. These regional measurements of climate dynamics are complemented by stratigraphic observations in five basins with lengthy stratigraphic and paleoenvironmental records: the mid-Pleistocene Olorgesailie Basin, the Plio-Pleistocene Turkana and Olduvai Basins, and the Pliocene Tugen Hills sequence and Hadar Basin--all of which show that highly variable landscapes inhabited by hominin populations were indeed concentrated in predicted stages of prolonged high climate variability. Second, stringent null-model tests demonstrate a significant association of currently known first and last appearance datums (FADs and LADs) of the major hominin lineages, suites of technological behaviors, and dispersal events with the predicted intervals of prolonged high climate variability. Palynological study in the Nihewan Basin, China, provides a third test, which shows the occupation of highly diverse habitats in eastern Asia, consistent with the predicted increase in adaptability in dispersing Oldowan hominins. Integration of fossil, archeological

  5. Calculating hominin and nonhuman anthropoid femoral head diameter from acetabular size.

    PubMed

    Plavcan, J Michael; Hammond, Ashley S; Ward, Carol V

    2014-11-01

    Femoral head size provides important information on body size in extinct species. Although it is well-known that femoral head size is correlated with acetabular size, the precision with which femoral head size can be estimated from acetabular size has not been quantified. The availability of accurate 3D surface models of fossil acetabular remains opens the possibility of obtaining accurate estimates of femoral head size from even fragmentary fossil remains [Hammond et al.,: Am J Phys Anthropol 150 (2013) 565-578]. Here we evaluate the relationship between spheres fit to surface models of the femoral head and acetabulum of a large sample of extant anthropoid primates. Sphere diameters are tightly correlated and scale isometrically. In spite of significant taxonomic and possibly functional differences in the relationship between femoral head size and acetabulum size, percent prediction errors of estimated femoral head size remain low regardless of the taxonomic composition of the reference sample. We provide estimates of femoral head size for a series of fossil hominins and monkeys. © 2014 Wiley Periodicals, Inc.

  6. Archaeology and age of a new hominin from Flores in eastern Indonesia.

    PubMed

    Morwood, M J; Soejono, R P; Roberts, R G; Sutikna, T; Turney, C S M; Westaway, K E; Rink, W J; Zhao, J-X; van den Bergh, G D; Due, Rokus Awe; Hobbs, D R; Moore, M W; Bird, M I; Fifield, L K

    2004-10-28

    Excavations at Liang Bua, a large limestone cave on the island of Flores in eastern Indonesia, have yielded evidence for a population of tiny hominins, sufficiently distinct anatomically to be assigned to a new species, Homo floresiensis. The finds comprise the cranial and some post-cranial remains of one individual, as well as a premolar from another individual in older deposits. Here we describe their context, implications and the remaining archaeological uncertainties. Dating by radiocarbon (14C), luminescence, uranium-series and electron spin resonance (ESR) methods indicates that H. floresiensis existed from before 38,000 years ago (kyr) until at least 18 kyr. Associated deposits contain stone artefacts and animal remains, including Komodo dragon and an endemic, dwarfed species of Stegodon. H. floresiensis originated from an early dispersal of Homo erectus (including specimens referred to as Homo ergaster and Homo georgicus) that reached Flores, and then survived on this island refuge until relatively recently. It overlapped significantly in time with Homo sapiens in the region, but we do not know if or how the two species interacted.

  7. Variability in an early hominin percussive tradition: the Acheulean versus cultural variation in modern chimpanzee artefacts

    PubMed Central

    Gowlett, J. A. J.

    2015-01-01

    Percussion makes a vital link between the activities of early human ancestors and other animals in tool-use and tool-making. Far more of the early human actions are preserved as archaeology, since the percussion was largely used for making hard tools of stone, rather than for direct access to food. Both primate tools and early hominin tools, however, offer a means to exploring variability in material culture, a strong focus of interest in recent primate studies. This paper charts such variability in the Acheulean, the longest-lasting tool tradition, extant form about 1.7 to about 0.1 Ma, and well known for its characteristic handaxes. The paper concentrates on the African record, although the Acheulean was also known in Europe and Asia. It uses principal components and discriminant analysis to examine the measurements from 66 assemblages (whole toolkits), and from 18 sets of handaxes. Its review of evidence confirms that there is deep-seated pattern in the variation, with variability within a site complex often matching or exceeding that between sites far distant in space and time. Current techniques of study allow comparisons of handaxes far more easily than for other components, stressing a need to develop common practice in measurement and analysis. The data suggest, however, that a higher proportion of traits recurs widely in Acheulean toolkits than in the chimpanzee record. PMID:26483536

  8. Testing Dietary Hypotheses of East African Hominines Using Buccal Dental Microwear Data

    PubMed Central

    Martínez, Laura Mónica; Estebaranz-Sánchez, Ferran; Galbany, Jordi

    2016-01-01

    There is much debate on the dietary adaptations of the robust hominin lineages during the Pliocene-Pleistocene transition. It has been argued that the shift from C3 to C4 ecosystems in Africa was the main factor responsible for the robust dental and facial anatomical adaptations of Paranthropus taxa, which might be indicative of the consumption of fibrous, abrasive plant foods in open environments. However, occlusal dental microwear data fail to provide evidence of such dietary adaptations and are not consistent with isotopic evidence that supports greater C4 food intake for the robust clades than for the gracile australopithecines. We provide evidence from buccal dental microwear data that supports softer dietary habits than expected for P. aethiopicus and P. boisei based both on masticatory apomorphies and isotopic analyses. On one hand, striation densities on the buccal enamel surfaces of paranthropines teeth are low, resembling those of H. habilis and clearly differing from those observed on H. ergaster, which display higher scratch densities indicative of the consumption of a wide assortment of highly abrasive foodstuffs. Buccal dental microwear patterns are consistent with those previously described for occlusal enamel surfaces, suggesting that Paranthropus consumed much softer diets than previously presumed and thus calling into question a strict interpretation of isotopic evidence. On the other hand, the significantly high buccal scratch densities observed in the H. ergaster specimens are not consistent with a highly specialized, mostly carnivorous diet; instead, they support the consumption of a wide range of highly abrasive food items. PMID:27851745

  9. Form and function of the human and chimpanzee forefoot: implications for early hominin bipedalism

    PubMed Central

    Fernández, Peter J.; Holowka, Nicholas B.; Demes, Brigitte; Jungers, William L.

    2016-01-01

    During bipedal walking, modern humans dorsiflex their forefoot at the metatarsophalangeal joints (MTPJs) prior to push off, which tightens the plantar soft tissues to convert the foot into a stiff propulsive lever. Particular features of metatarsal head morphology such as “dorsal doming” are thought to facilitate this stiffening mechanism. In contrast, chimpanzees are believed to possess MTPJ morphology that precludes high dorsiflexion excursions during terrestrial locomotion. The morphological affinity of the metatarsal heads has been used to reconstruct locomotor behavior in fossil hominins, but few studies have provided detailed empirical data to validate the assumed link between morphology and function at the MTPJs. Using three-dimensional kinematic and morphometric analyses, we show that humans push off with greater peak dorsiflexion angles at all MTPJs than do chimpanzees during bipedal and quadrupedal walking, with the greatest disparity occurring at MTPJ 1. Among MTPJs 2–5, both species exhibit decreasing peak angles from medial to lateral. This kinematic pattern is mirrored in the morphometric analyses of metatarsal head shape. Analyses of Australopithecus afarensis metatarsals reveal morphology intermediate between humans and chimpanzees, suggesting that this species used different bipedal push-off kinematics than modern humans, perhaps resulting in a less efficient form of bipedalism. PMID:27464580

  10. Fossil Carder Bee's Nest from the Hominin Locality of Taung, South Africa.

    PubMed

    Parker, Jennifer F; Hopley, Philip J; Kuhn, Brian F

    The Buxton-Norlim Limeworks southwest of Taung, South Africa, is renowned for the discovery of the first Australopithecus africanus fossil, the 'Taung Child'. The hominin was recovered from a distinctive pink calcrete that contains an abundance of invertebrate ichnofauna belonging to the Coprinisphaera ichnofacies. Here we describe the first fossil bee's nest, attributed to the ichnogenus Celliforma, from the Plio-Pleistocene of Africa. Petrographic examination of a cell lining revealed the preservation of an intricate organic matrix lined with the calcitic casts of numerous plant trichomes-a nesting behaviour unique to the modern-day carder bees (Anthidiini). The presence of Celliforma considered alongside several other recorded ichnofossils can be indicative of a dry, savannah environment, in agreement with recent work on the palaeoenvironment of Plio-Pleistocene southern Africa. Moreover, the occurrence of ground-nesting bees provides further evidence that the pink calcrete deposits are of pedogenic origin, rather than speleogenic origin as has previously been assumed. This study demonstrates the potential value of insect trace fossils as palaeoenvironmental indicators.

  11. Mechanisms and causes of wear in tooth enamel: implications for hominin diets

    PubMed Central

    Lucas, Peter W.; Omar, Ridwaan; Al-Fadhalah, Khaled; Almusallam, Abdulwahab S.; Henry, Amanda G.; Michael, Shaji; Thai, Lidia Arockia; Watzke, Jörg; Strait, David S.; Atkins, Anthony G.

    2013-01-01

    The wear of teeth is a major factor limiting mammalian lifespans in the wild. One method of describing worn surfaces, dental microwear texture analysis, has proved powerful for reconstructing the diets of extinct vertebrates, but has yielded unexpected results in early hominins. In particular, although australopiths exhibit derived craniodental features interpreted as adaptations for eating hard foods, most do not exhibit microwear signals indicative of this diet. However, no experiments have yet demonstrated the fundamental mechanisms and causes of this wear. Here, we report nanowear experiments where individual dust particles, phytoliths and enamel chips were slid across a flat enamel surface. Microwear features produced were influenced strongly by interacting mechanical properties and particle geometry. Quartz dust was a rigid abrasive, capable of fracturing and removing enamel pieces. By contrast, phytoliths and enamel chips deformed during sliding, forming U-shaped grooves or flat troughs in enamel, without tissue loss. Other plant tissues seem too soft to mark enamel, acting as particle transporters. We conclude that dust has overwhelming importance as a wear agent and that dietary signals preserved in dental microwear are indirect. Nanowear studies should resolve controversies over adaptive trends in mammals like enamel thickening or hypsodonty that delay functional dental loss. PMID:23303220

  12. Adaptive Flexibility of Oldowan Hominins: Secondary Use of Flakes at Bizat Ruhama, Israel

    PubMed Central

    Zaidner, Yossi

    2013-01-01

    The lithic assemblage of the Early Pleistocene site of Bizat Ruhama, Israel demonstrates the earliest evidence for systematic secondary knapping of flakes. The site, dated to the Matuyama chron, is one of the earliest primary context Oldowan occurrences in Eurasia. According to the experimental replication of the stone-tool production sequence, the secondary knapping of flakes was a part of a multi-stage operational sequence targeted at the production of small (<2 cm) flakes. This sequence included four stages: acquisition of chert pebbles, production of flakes, deliberate selection of flakes of specific morphologies, and their secondary knapping by free-hand or bipolar methods. The results suggest that flakes with retouch-like scars that were produced during this sequence and which commonly are interpreted as shaped tools are unintentional waste products of the small flake production. The intentional manufacture of very small flakes at Bizat Ruhama was probably an economic response to the raw material constrains. Systematic secondary knapping of flakes has not yet been reported from other Early Pleistocene sites. Systematic secondary knapping for small flake production became increasingly important only in the lithic industries of the second half of the Middle Pleistocene, almost a million years later. The results from Bizat Ruhama indicate that Oldowan stone-tool production sequence was conceptually more complex than previously suggested and offer a new perspective on the capabilities for invention and the adaptive flexibility of the Oldowan hominins. PMID:23840539

  13. Messinian age and savannah environment of the possible hominin Graecopithecus from Europe.

    PubMed

    Böhme, Madelaine; Spassov, Nikolai; Ebner, Martin; Geraads, Denis; Hristova, Latinka; Kirscher, Uwe; Kötter, Sabine; Linnemann, Ulf; Prieto, Jérôme; Roussiakis, Socrates; Theodorou, George; Uhlig, Gregor; Winklhofer, Michael

    2017-01-01

    Dating fossil hominids and reconstructing their environments is critically important for understanding human evolution. Here we date the potentially oldest hominin, Graecopithecus freybergi from Europe and constrain the environmental conditions under which it thrived. For the Graecopithecus-bearing Pikermi Formation of Attica/Greece, a saline aeolian dust deposit of North African (Sahara) provenance, we obtain an age of 7.37-7.11 Ma, which is coeval with a dramatic cooling in the Mediterranean region at the Tortonian-Messinian transition. Palaeobotanic proxies demonstrate C4-grass dominated wooded grassland-to-woodland habitats of a savannah biome for the Pikermi Formation. Faunal turnover at the Tortonian-Messinian transition led to the spread of new mammalian taxa along with Graecopithecus into Europe. The type mandible of G. freybergi from Pyrgos (7.175 Ma) and the single tooth (7.24 Ma) from Azmaka (Bulgaria) represent the first hominids of Messinian age from continental Europe. Our results suggest that major splits in the hominid family occurred outside Africa.

  14. Embodied niche construction in the hominin lineage: semiotic structure and sustained attention in human embodied cognition

    PubMed Central

    Stutz, Aaron J.

    2014-01-01

    Human evolution unfolded through a rather distinctive, dynamically constructed ecological niche. The human niche is not only generally terrestrial in habitat, while being flexibly and extensively heterotrophic in food-web connections. It is also defined by semiotically structured and structuring embodied cognitive interfaces, connecting the individual organism with the wider environment. The embodied dimensions of niche-population co-evolution have long involved semiotic system construction, which I hypothesize to be an evolutionarily primitive aspect of learning and higher-level cognitive integration and attention in the great apes and humans alike. A clearly pre-linguistic form of semiotic cognitive structuration is suggested to involve recursively learned and constructed object icons. Higher-level cognitive iconic representation of visually, auditorily, or haptically perceived extrasomatic objects would be learned and evoked through indexical connections to proprioceptive and affective somatic states. Thus, private cognitive signs would be defined, not only by their learned and perceived extrasomatic referents, but also by their associations to iconically represented somatic states. This evolutionary modification of animal associative learning is suggested to be adaptive in ecological niches occupied by long-lived, large-bodied ape species, facilitating memory construction and recall in highly varied foraging and social contexts, while sustaining selective attention during goal-directed behavioral sequences. The embodied niche construction (ENC) hypothesis of human evolution posits that in the early hominin lineage, natural selection further modified the ancestral ape semiotic adaptations, favoring the recursive structuration of concise iconic narratives of embodied interaction with the environment. PMID:25136323

  15. Manual Loading Distribution During Carrying Behaviors: Implications for the Evolution of the Hominin Hand

    PubMed Central

    Key, Alastair J. M.

    2016-01-01

    The human hand is unparalleled amongst primates in its ability to manipulate objects forcefully and dexterously. Previous research has predominantly sought to explain the evolution of these capabilities through an adaptive relationship between more modern human-like anatomical features in the upper limb and increased stone tool production and use proficiency. To date, however, we know little about the influence that other manipulatively demanding behaviors may have had upon the evolution of the human hand. The present study addresses one aspect of this deficiency by examining the recruitment of the distal phalanges during a range of manual transportation (i.e., carrying) events related to hominin behavioral repertoires during the Plio-Pleistocene. Specifically, forces on the volar pad of each digit are recorded during the transportation of stones and wooden branches that vary in weight and size. Results indicate that in most instances, the index and middle fingers are recruited to a significantly greater extent than the other three digits during carrying events. Relative force differences between digits were, however, dependent upon the size and weight of the object transported. Carrying behaviors therefore appear unlikely to have contributed to the evolution of the robust thumb anatomy observed in the human hand. Rather, results suggest that the manual transportation of objects may plausibly have influenced the evolution of the human gripping capabilities and the 3rd metacarpal styloid process. PMID:27695044

  16. Enamel hypoplasias and physiological stress in the Sima de los Huesos Middle Pleistocene hominins.

    PubMed

    Cunha, E; Rozzi, F Ramirez; Bermúdez de Castro, J M; Martinón-Torres, M; Wasterlain, S N; Sarmiento, S

    2004-11-01

    This study presents an analysis of linear enamel hypoplasias (LEH) and plane-form defects (PFD) in the hominine dental sample from the Sima de los Huesos (SH) Middle Pleistocene site in Atapuerca (Spain). The SH sample comprises 475 teeth, 467 permanent and 8 deciduous, belonging to a minimum of 28 individuals. The method for recording PFD and LEH is discussed, as well as the definition of LEH. The prevalence of LEH and PFD in SH permanent dentition (unilateral total count) is 4.6% (13/280). Only one deciduous tooth (lower dc) showed an enamel disruption. Prevalence by individual ranges from 18.7-30%. The most likely explanation for the relatively low LEH and PFD prevalence in the SH sample suggests that the SH population exhibited a low level of developmental stress. The age at occurrence of LEH and PFD was determined by counting the number of perikymata between each lesion and the cervix of the tooth. Assuming a periodicity of nine days for the incremental lines, the majority of LEH in the SH sample occurred during the third year of life and may be related to the metabolic stress associated with weaning.

  17. Manual Loading Distribution During Carrying Behaviors: Implications for the Evolution of the Hominin Hand.

    PubMed

    Key, Alastair J M

    2016-01-01

    The human hand is unparalleled amongst primates in its ability to manipulate objects forcefully and dexterously. Previous research has predominantly sought to explain the evolution of these capabilities through an adaptive relationship between more modern human-like anatomical features in the upper limb and increased stone tool production and use proficiency. To date, however, we know little about the influence that other manipulatively demanding behaviors may have had upon the evolution of the human hand. The present study addresses one aspect of this deficiency by examining the recruitment of the distal phalanges during a range of manual transportation (i.e., carrying) events related to hominin behavioral repertoires during the Plio-Pleistocene. Specifically, forces on the volar pad of each digit are recorded during the transportation of stones and wooden branches that vary in weight and size. Results indicate that in most instances, the index and middle fingers are recruited to a significantly greater extent than the other three digits during carrying events. Relative force differences between digits were, however, dependent upon the size and weight of the object transported. Carrying behaviors therefore appear unlikely to have contributed to the evolution of the robust thumb anatomy observed in the human hand. Rather, results suggest that the manual transportation of objects may plausibly have influenced the evolution of the human gripping capabilities and the 3rd metacarpal styloid process.

  18. Testing Dietary Hypotheses of East African Hominines Using Buccal Dental Microwear Data.

    PubMed

    Martínez, Laura Mónica; Estebaranz-Sánchez, Ferran; Galbany, Jordi; Pérez-Pérez, Alejandro

    2016-01-01

    There is much debate on the dietary adaptations of the robust hominin lineages during the Pliocene-Pleistocene transition. It has been argued that the shift from C3 to C4 ecosystems in Africa was the main factor responsible for the robust dental and facial anatomical adaptations of Paranthropus taxa, which might be indicative of the consumption of fibrous, abrasive plant foods in open environments. However, occlusal dental microwear data fail to provide evidence of such dietary adaptations and are not consistent with isotopic evidence that supports greater C4 food intake for the robust clades than for the gracile australopithecines. We provide evidence from buccal dental microwear data that supports softer dietary habits than expected for P. aethiopicus and P. boisei based both on masticatory apomorphies and isotopic analyses. On one hand, striation densities on the buccal enamel surfaces of paranthropines teeth are low, resembling those of H. habilis and clearly differing from those observed on H. ergaster, which display higher scratch densities indicative of the consumption of a wide assortment of highly abrasive foodstuffs. Buccal dental microwear patterns are consistent with those previously described for occlusal enamel surfaces, suggesting that Paranthropus consumed much softer diets than previously presumed and thus calling into question a strict interpretation of isotopic evidence. On the other hand, the significantly high buccal scratch densities observed in the H. ergaster specimens are not consistent with a highly specialized, mostly carnivorous diet; instead, they support the consumption of a wide range of highly abrasive food items.

  19. Hypothesis: brain size and skull shape as criteria for a new hominin family tree.

    PubMed

    Chardin, Pierre

    2014-10-01

    Today, gorillas and chimpanzees live in tropical forests, where acid soils do not favor fossilization. It is thus widely believed that there are no fossils of chimpanzees or gorillas. However, four teeth of a 0.5-million-year (Ma)-old chimpanzee were discovered in the rift valley of Kenya (McBrearty and Jablonski, 2005), and a handful of teeth of a 10-Ma-old gorilla-like creature were found in Ethiopia (Suwa et al., 2007), close to the major sites of Homo discoveries. These discoveries indicate that chimpanzees and gorillas once shared their range with early Homo. However, the thousands of hominin fossils discovered in the past century have all been attributed to the Homo line. Thus far, our family tree looks like a bush with many dead-branches. If one admits the possibility that the australopithecines can also be the ancestors of African great apes, one can place Paranthropus on the side of gorilla ancestors and divide the remaining Australopithecus based on the brain size into the two main lines of humans and chimpanzees, thereby resulting in a coherent family tree.

  20. Social organization and the evolution of cumulative technology in apes and hominins.

    PubMed

    Pradhan, Gauri R; Tennie, Claudio; van Schaik, Carel P

    2012-07-01

    Culturally supported accumulation (or ratcheting) of technological complexity is widely seen as characterizing hominin technology relative to that of the extant great apes, and thus as representing a threshold in cultural evolution. To explain this divide, we modeled the process of cultural accumulation of technology, which we defined as adding new actions to existing ones to create new functional combinations, based on a model for great ape tool use. The model shows that intraspecific and interspecific variation in the presence of simple and cumulative technology among extant orangutans and chimpanzees is largely due to variation in sociability, and hence opportunities for social learning. The model also suggests that the adoption of extensive allomaternal care (cooperative breeding) in early Pleistocene Homo, which led to an increase in sociability and to teaching, and hence increased efficiency of social learning, was enough to facilitate technological ratcheting. Hence, socioecological changes, rather than advances in cognitive abilities, can account for the cumulative cultural changes seen until the origin of the Acheulean. The consequent increase in the reliance on technology could have served as the pacemaker for increased cognitive abilities. Our results also suggest that a more important watershed in cultural evolution was the rise of donated culture (technology or concepts), in which technology or concepts was transferred to naïve individuals, allowing them to skip many learning steps, and specialization arose, which allowed individuals to learn only a subset of the population's skills. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. An ontogenetic framework linking locomotion and trabecular bone architecture with applications for reconstructing hominin life history.

    PubMed

    Raichlen, David A; Gordon, Adam D; Foster, Adam D; Webber, James T; Sukhdeo, Simone M; Scott, Robert S; Gosman, James H; Ryan, Timothy M

    2015-04-01

    The ontogeny of bipedal walking is considered uniquely challenging, due in part to the balance requirements of single limb support. Thus, locomotor development in humans and our bipedal ancestors may track developmental milestones including the maturation of the neuromuscular control system. Here, we examined the ontogeny of locomotor mechanics in children aged 1-8, and bone growth and development in an age-matched skeletal sample to identify bony markers of locomotor development. We show that step-to-step variation in mediolateral tibia angle relative to the vertical decreases with age, an indication that older children increase stability. Analyses of trabecular bone architecture in the distal tibia of an age-matched skeletal sample (the Norris Farms #36 archaeological skeletal collection) show a bony signal of this shift in locomotor stability. Using a grid of eleven cubic volumes of interest (VOI) in the distal metaphysis of each tibia, we show that the degree of anisotropy (DA) of trabecular struts changes with age. Intra-individual variation in DA across these VOIs is generally high at young ages, likely reflecting variation in loading due to kinematic instability. With increasing age, mean DA converges on higher values and becomes less variable across the distal tibia. We believe the ontogeny of distal tibia trabecular architecture reflects the development of locomotor stability in bipeds. We suggest this novel bony marker of development may be used to assess the relationship between locomotor development and other life history milestones in fossil hominins. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. High- and low-latitude orbital forcing of early hominin habitats in South Africa

    NASA Astrophysics Data System (ADS)

    Hopley, Philip J.; Weedon, Graham P.; Marshall, Jim D.; Herries, Andy I. R.; Latham, Alf G.; Kuykendall, Kevin L.

    2007-04-01

    Reconstructions of African palaeoenvironments are essential for a full understanding of early hominin evolution, but they are often hampered by low-resolution or discontinuous climatic data. Here we present high-resolution oxygen ( δ18O) and carbon ( δ13C) isotope time series for the Pliocene/early Pleistocene (1.99 to 1.52 Ma) of South Africa, derived from the Buffalo Cave flowstone deposit. The δ18O data are dominated by variations at the orbital precession period (18-23 ka), as is typical for records of sub-tropical monsoon rainfall. The δ13C data indicate the proportion of savannah grasses (C 4 plants) compared to trees and shrubs (C 3 plants), and this signal is dominated by an obliquity periodicity (40 ka), commonly associated with high-latitude ice-sheet dynamics. A rapid increase in savannah grass proportions between 1.78 and 1.69 Ma coincides with a pulse in African mammal turnover, and lends support to an adaptive link between the appearance of African Homo erectus and the increasingly savannah-dominated environment.

  3. Messinian age and savannah environment of the possible hominin Graecopithecus from Europe

    PubMed Central

    Spassov, Nikolai; Ebner, Martin; Geraads, Denis; Hristova, Latinka; Kirscher, Uwe; Kötter, Sabine; Linnemann, Ulf; Prieto, Jérôme; Roussiakis, Socrates; Theodorou, George; Uhlig, Gregor; Winklhofer, Michael

    2017-01-01

    Dating fossil hominids and reconstructing their environments is critically important for understanding human evolution. Here we date the potentially oldest hominin, Graecopithecus freybergi from Europe and constrain the environmental conditions under which it thrived. For the Graecopithecus-bearing Pikermi Formation of Attica/Greece, a saline aeolian dust deposit of North African (Sahara) provenance, we obtain an age of 7.37–7.11 Ma, which is coeval with a dramatic cooling in the Mediterranean region at the Tortonian-Messinian transition. Palaeobotanic proxies demonstrate C4-grass dominated wooded grassland-to-woodland habitats of a savannah biome for the Pikermi Formation. Faunal turnover at the Tortonian-Messinian transition led to the spread of new mammalian taxa along with Graecopithecus into Europe. The type mandible of G. freybergi from Pyrgos (7.175 Ma) and the single tooth (7.24 Ma) from Azmaka (Bulgaria) represent the first hominids of Messinian age from continental Europe. Our results suggest that major splits in the hominid family occurred outside Africa. PMID:28531204

  4. Olduvai Hominin 8 foot pathology: a comparative study attempting a differential diagnosis.

    PubMed

    Weiss, Elizabeth

    2012-02-01

    Olduvai Hominin (OH) 8, a 1.76 million year old left foot skeleton, has osteophytic lipping on the metatarsal bases, which when compared to a modern sample, may help paleoanthropologists determine whether the foot bones represent an injured subadult or an osteoarthritic adult. This study compares the OH 8 lipping pattern to those of 140 individual Amerindians comprising four different age classes to determine whether the OH 8 lipping is likely to be age-related osteoarthritis. OH 8 metatarsal lipping followed a pattern similar to that determined in the comparative sample to be age-related osteoarthritis. Similarities include metatarsal base lipping that is frequently located on the dorsal surface, metatarsal base lipping that is more severe on the lateral metatarsals compared to the medial metatarsals, and the presence of a pseudojoint between metatarsal 1 and metatarsal 2. The chance of finding an individual with osteoarthritis lipping increases from 3.45% in the age group 18-22 years to 55% in individuals over 35 years. The chance of finding a pseudojoint increases from 1.32% in non-osteoarthritic individuals to 15.15% in individuals with osteoarthritis. Results from this study indicate that the OH 8 foot bones are most likely from an adult and more likely to belong to Paranthropus boisei, the skull of which was found in the same excavations with OH 8, than to the juvenile Homo habilis holotype.

  5. Craniofacial modularity, character analysis, and the evolution of the premaxilla in early African hominins.

    PubMed

    Villmoare, Brian A; Dunmore, Christopher; Kilpatrick, Shaun; Oertelt, Nadja; Depew, Michael J; Fish, Jennifer L

    2014-12-01

    Phylogenetic analyses require evolutionarily independent characters, but there is no consensus, nor has there been a clear methodology presented on how to define character independence in a phylogenetic context, particularly within a complex morphological structure such as the skull. Following from studies of craniofacial development, we hypothesize that the premaxilla is an independent evolutionary module with two integrated characters that have traditionally been treated as independent. We test this hypothesis on a large sample of primate skulls and find evidence supporting the premaxilla as an independent module within the larger module of the palate. Additionally, our data indicate that the convexity of the nasoalveolar clivus and the contour of the alveolus are integrated within the premaxilla. We show that the palate itself is composed of two distinct modules: the FNP-derived premaxillae and the mxBA1-derived maxillae and palatines. Application of our data to early African hominin facial morphology suggests that at least three separate transitions contributed to robust facial morphology: 1) an increase in the size of the post-canine dentition housed within the maxillae and palatines, 2) modification of the premaxilla generating a concave clivus and reduced incisor alveolus, and 3) modification of the zygomatic, shifting the zygomatic root and lateral face anteriorly. These data lend support to the monophyly of Paranthropus boisei and Paranthropus robustus, and provide mounting evidence in favor of a Paranthropus clade. This study also highlights the utility of applying developmental evidence to studies of morphological evolution.

  6. Variability in an early hominin percussive tradition: the Acheulean versus cultural variation in modern chimpanzee artefacts.

    PubMed

    Gowlett, J A J

    2015-11-19

    Percussion makes a vital link between the activities of early human ancestors and other animals in tool-use and tool-making. Far more of the early human actions are preserved as archaeology, since the percussion was largely used for making hard tools of stone, rather than for direct access to food. Both primate tools and early hominin tools, however, offer a means to exploring variability in material culture, a strong focus of interest in recent primate studies. This paper charts such variability in the Acheulean, the longest-lasting tool tradition, extant form about 1.7 to about 0.1 Ma, and well known for its characteristic handaxes. The paper concentrates on the African record, although the Acheulean was also known in Europe and Asia. It uses principal components and discriminant analysis to examine the measurements from 66 assemblages (whole toolkits), and from 18 sets of handaxes. Its review of evidence confirms that there is deep-seated pattern in the variation, with variability within a site complex often matching or exceeding that between sites far distant in space and time. Current techniques of study allow comparisons of handaxes far more easily than for other components, stressing a need to develop common practice in measurement and analysis. The data suggest, however, that a higher proportion of traits recurs widely in Acheulean toolkits than in the chimpanzee record. © 2015 The Author(s).

  7. Fossil Carder Bee's Nest from the Hominin Locality of Taung, South Africa

    PubMed Central

    Parker, Jennifer F.; Hopley, Philip J.; Kuhn, Brian F.

    2016-01-01

    The Buxton-Norlim Limeworks southwest of Taung, South Africa, is renowned for the discovery of the first Australopithecus africanus fossil, the ‘Taung Child’. The hominin was recovered from a distinctive pink calcrete that contains an abundance of invertebrate ichnofauna belonging to the Coprinisphaera ichnofacies. Here we describe the first fossil bee’s nest, attributed to the ichnogenus Celliforma, from the Plio-Pleistocene of Africa. Petrographic examination of a cell lining revealed the preservation of an intricate organic matrix lined with the calcitic casts of numerous plant trichomes–a nesting behaviour unique to the modern-day carder bees (Anthidiini). The presence of Celliforma considered alongside several other recorded ichnofossils can be indicative of a dry, savannah environment, in agreement with recent work on the palaeoenvironment of Plio-Pleistocene southern Africa. Moreover, the occurrence of ground-nesting bees provides further evidence that the pink calcrete deposits are of pedogenic origin, rather than speleogenic origin as has previously been assumed. This study demonstrates the potential value of insect trace fossils as palaeoenvironmental indicators. PMID:27682845

  8. New high-resolution computed tomography data of the Taung partial cranium and endocast and their bearing on metopism and hominin brain evolution.

    PubMed

    Holloway, Ralph L; Broadfield, Douglas C; Carlson, Kristian J

    2014-09-09

    Falk and colleagues [Falk D, Zollikofer CP, Morimoto N, Ponce de León MS (2012) Proc Natl Acad Sci U S A 109(22):8467-8470] hypothesized that selective pressures favored late persistence of a metopic suture and open anterior fontanelle early in hominin evolution, and they put an emphasis on the Taung Child (Australopithecus africanus) as evidence for the antiquity of these adaptive features. They suggested three mutually nonexclusive pressures: an "obstetric dilemma," high early postnatal brain growth rates, and neural reorganization in the frontal cortex. To test this hypothesis, we obtained the first high-resolution computed tomography (CT) data from the Taung hominin. These high-resolution image data and an examination of the hominin fossil record do not support the metopic and fontanelle features proposed by Falk and colleagues. Although a possible remnant of the metopic suture is observed in the nasion-glabella region of the Taung partial cranium (but not along the frontal crest), this character state is incongruent with the zipper model of metopic closure described by Falk and colleagues. Nor do chimpanzee and bonobo endocast data support the assertion that delayed metopic closure in Taung is necessary because of widening (reorganization) of the prefrontal or frontal cortex. These results call into question the adaptive value of delaying metopic closure, and particularly its antiquity in hominin evolution. Further data from hominoids and hominins are required to support the proposed adaptive arguments, particularly an obstetric dilemma placing constraints on neural and cranial development in Australopithecus.

  9. First evidence of a bipartite medial cuneiform in the hominin fossil record: a case report from the Early Pleistocene site of Dmanisi

    PubMed Central

    Jashashvili, Tea; Ponce de León, Marcia S; Lordkipanidze, David; Zollikofer, Christoph P E

    2010-01-01

    A medial cuneiform exhibiting complete bipartition was discovered at the Early Pleistocene site of Dmanisi, Georgia. The specimen is the oldest known instance of this anatomical variant in the hominin fossil record. Here we compare developmental variation of the medial cuneiform in fossil hominins, extant humans and great apes, and discuss potential implications of bipartition for hominin foot phylogeny and function. Complete bipartition is rare among modern humans (< 1%); incomplete bipartition was found in 2 of 200 examined great ape specimens and also appears in the form of a divided distal articular surface in the Stw573c Australopithecus africanus specimen. Although various developmental pathways lead to medial cuneiform bipartition, it appears that the bipartite bone does not deviate significantly from normal overall morphology. Together, these data indicate that bipartition represents a phyletically old developmental variant of the medial cuneiform, which does not, however, affect the species-specific morphology and function of this bone. PMID:20579174

  10. Out of Africa: modern human origins special feature: middle and later Pleistocene hominins in Africa and Southwest Asia.

    PubMed

    Rightmire, G Philip

    2009-09-22

    Approximately 700,000 years ago, Homo erectus in Africa was giving way to populations with larger brains accompanied by structural adjustments to the vault, cranial base, and face. Such early Middle Pleistocene hominins were not anatomically modern. Their skulls display strong supraorbital tori above projecting faces, flattened frontals, and less parietal expansion than is the case for Homo sapiens. Postcranial remains seem also to have archaic features. Subsequently, some groups evolved advanced skeletal morphology, and by ca. 200,000 years ago, individuals more similar to recent humans are present in the African record. These fossils are associated with Middle Stone Age lithic assemblages and, in some cases, Acheulean tools. Crania from Herto in Ethiopia carry defleshing cutmarks and superficial scoring that may be indicative of mortuary practices. Despite these signs of behavioral innovation, neither the Herto hominins, nor others from Late Pleistocene sites such as Klasies River in southern Africa and Skhūl/Qafzeh in Israel, can be matched in living populations. Skulls are quite robust, and it is only after approximately 35,000 years ago that people with more gracile, fully modern morphology make their appearance. Not surprisingly, many questions concerning this evolutionary history have been raised. Attention has centered on systematics of the mid-Pleistocene hominins, their paleobiology, and the timing of dispersals that spread H. sapiens out of Africa and across the Old World. In this report, I discuss structural changes characterizing the skulls from different time periods, possible regional differences in morphology, and the bearing of this evidence on recognizing distinct species.

  11. Early Pleistocene hominin deciduous teeth from the Homo antecessor Gran Dolina-TD6 bearing level (Sierra de Atapuerca, Spain).

    PubMed

    Bermúdez de Castro, José María; Martinón-Torres, María; Martín-Francés, Laura; Martínez de Pinillos, Marina; Modesto-Mata, Mario; García-Campos, Cecilia; Wu, Xiujie; Xing, Song; Liu, Wu

    2017-07-01

    During the last 13 years, the late Early Pleistocene Gran Dolina-TD6-2 level (Sierra de Atapuerca, northern Spain) has yielded an additional sample of 26 dental specimens attributed to Homo antecessor. In this report, we present a descriptive and comparative study of the six deciduous teeth. We provide external and internal morphological descriptions following classical terminology, as well as the mesiodistal and buccolingual measurements of the teeth. The internal morphology was described by means of micro-CT technique. The TD6 deciduous teeth preserve primitive features regarding the Homo clade, such as the presence of styles in lower and upper canines and developed anterior and posterior foveae in the dm2 . However, other features related to the complexity of the crown morphology (e.g., cingulum) are not present in this sample. Furthermore, the great reduction of the talonid of the dm1 s is also noteworthy. Despite the limited comparative evidence, the presence of a remarkably well-developed tuberculum molare in the dm(1) and dm1 s from TD6 can be also considered a derived feature in the genus Homo. The TD6 hominins exhibit dental dimensions similar to those of other Pleistocene hominins. The dm1 s are buccolingually elongated and the buccolingual diameter of ATD6-93 is the largest recorded so far in the Homo fossil record. This study expands the list of plesiomorphic features of H. antecessor, and provides some information on the evolutionary status of this species. However, the identification of some advanced traits evinces a step towards the derived morphology of European Pleistocene teeth. The study of the deciduous dentition confirms the mosaic pattern of H. antecessor morphology revealed in previous studies of this hominin sample. © 2017 Wiley Periodicals, Inc.

  12. Measure, Then Show: Grasping Human Evolution Through an Inquiry-Based, Data-driven Hominin Skulls Lab.

    PubMed

    Bayer, Chris N; Luberda, Michael

    2016-01-01

    Incomprehension and denial of the theory of evolution among high school students has been observed to also occur when teachers are not equipped to deliver a compelling case also for human evolution based on fossil evidence. This paper assesses the outcomes of a novel inquiry-based paleoanthropology lab teaching human evolution to high-school students. The inquiry-based Be a Paleoanthropologist for a Day lab placed a dozen hominin skulls into the hands of high-school students. Upon measuring three variables of human evolution, students explain what they have observed and discuss findings. In the 2013/14 school year, 11 biology classes in 7 schools in the Greater New Orleans area participated in this lab. The interviewed teacher cohort unanimously agreed that the lab featuring hominin skull replicas and stimulating student inquiry was a pedagogically excellent method of delivering the subject of human evolution. First, the lab's learning path of transforming facts to data, information to knowledge, and knowledge to acceptance empowered students to themselves execute part of the science that underpins our understanding of deep time hominin evolution. Second, although challenging, the hands-on format of the lab was accessible to high-school students, most of whom were readily able to engage the lab's scientific process. Third, the lab's exciting and compelling pedagogy unlocked higher order thinking skills, effectively activating the cognitive, psychomotor and affected learning domains as defined in Bloom's taxonomy. Lastly, the lab afforded students a formative experience with a high degree of retention and epistemic depth. Further study is warranted to gauge the degree of these effects.

  13. Paleolithic hominin remains from Eshkaft-e Gavi (southern Zagros Mountains, Iran): description, affinities, and evidence for butchery.

    PubMed

    Scott, Jeremiah E; Marean, Curtis W

    2009-09-01

    Eshkaft-e Gavi is a cave located in the southern Zagros Mountains of Iran and is one of the few archaeological sites in the region to preserve both Middle Paleolithic and Upper Paleolithic occupations. Excavation of the site in the 1970s yielded an assemblage of lithic and faunal remains, including ten hominin specimens: a mandibular molar, four cranial fragments, a clavicular diaphysis, the proximal half of a metacarpal, a fragment of os coxa, the proximal diaphysis of a juvenile femur, and a patella. The bones derive from a minimum of four individuals, including two juveniles. Although many of these remains could be Epi-Paleolithic in age, one of the juvenile specimens-the mandibular molar-occurs at the base of the cave's Upper Paleolithic sequence. The remains are very fragmentary, but those that preserve diagnostic morphology indicate that they represent modern humans. The molar is taxonomically diagnostic, thus confirming the association of the Aurignacian-like Baradostian Industry with modern humans. Four of the specimens-a piece of frontal bone, the clavicle, the juvenile femur, and the patella-display clear evidence for intentional butchery in the form of stone-tool cutmarks. These cutmarked specimens, along with a fragment of parietal bone, are also burned. Although this evidence is consistent with cannibalism, the small sample makes it difficult to say whether or not the individuals represented by the hominin remains were butchered and cooked for consumption. Nevertheless, the cutmarked Eshkaft-e Gavi specimens add to a growing sample of hominin remains extending back into the Plio-Pleistocene that display evidence of intentional defleshing.

  14. Measure, Then Show: Grasping Human Evolution Through an Inquiry-Based, Data-driven Hominin Skulls Lab

    PubMed Central

    Luberda, Michael

    2016-01-01

    Incomprehension and denial of the theory of evolution among high school students has been observed to also occur when teachers are not equipped to deliver a compelling case also for human evolution based on fossil evidence. This paper assesses the outcomes of a novel inquiry-based paleoanthropology lab teaching human evolution to high-school students. The inquiry-based Be a Paleoanthropologist for a Day lab placed a dozen hominin skulls into the hands of high-school students. Upon measuring three variables of human evolution, students explain what they have observed and discuss findings. In the 2013/14 school year, 11 biology classes in 7 schools in the Greater New Orleans area participated in this lab. The interviewed teacher cohort unanimously agreed that the lab featuring hominin skull replicas and stimulating student inquiry was a pedagogically excellent method of delivering the subject of human evolution. First, the lab’s learning path of transforming facts to data, information to knowledge, and knowledge to acceptance empowered students to themselves execute part of the science that underpins our understanding of deep time hominin evolution. Second, although challenging, the hands-on format of the lab was accessible to high-school students, most of whom were readily able to engage the lab’s scientific process. Third, the lab’s exciting and compelling pedagogy unlocked higher order thinking skills, effectively activating the cognitive, psychomotor and affected learning domains as defined in Bloom’s taxonomy. Lastly, the lab afforded students a formative experience with a high degree of retention and epistemic depth. Further study is warranted to gauge the degree of these effects. PMID:27513927

  15. Was monogamy a key step on the hominin road? Reevaluating the monogamy hypothesis in the evolution of cooperative breeding.

    PubMed

    Kramer, Karen L; Russell, Andrew F

    2015-01-01

    Because human mothers routinely rely on others to help raise their young, humans have been characterized as cooperative breeders.(1-9) Several large-scale phylogenetic analyses have presented compelling evidence that monogamy preceded the evolution of cooperative breeding in a wide variety of nonhuman animals.(10-14) These studies have suggested that monogamy provides a general rule (the monogamy hypothesis) for explaining evolutionary transitions to cooperative breeding.(15) Given the prevalence of cooperative breeding in contemporary human societies, we evaluate whether this suggests a monogamous hominin past.

  16. Revised stratigraphy of Area 123, Koobi Fora, Kenya, and new age estimates of its fossil mammals, including hominins.

    PubMed

    Gathogo, Patrick N; Brown, Francis H

    2006-11-01

    Recent geologic study shows that all hominins and nearly all other published mammalian fossils from Paleontological Collection Area 123, Koobi Fora, Kenya, derive from levels between the KBS Tuff (1.87+/-0.02 Ma) and the Lower Ileret Tuff (1.53+/-0.01 Ma). More specifically, the fossils derive from 53 m of section below the Lower Ileret Tuff, an interval in which beds vary markedly laterally, especially those units containing molluscs and algal stromatolites. The upper Burgi Member (approximately 2.00-1.87 Ma) crops out only in the southwestern part of Area 123. Adjacent Area 110 contains larger exposures of the member, and there the KBS Tuff is preserved as an airfall ash in lacustrine deposits and also as a fluvially redeposited ash. We observed no mammalian fossils in situ in this member in Area 123, but surface specimens have been documented in some monographic treatments. Fossil hominins from Area 123 were attributed to strata above the KBS Tuff in the 1970s, but later they were assigned to strata below the KBS Tuff (now called the upper Burgi Member). This study definitively places the Area 123 hominins in the KBS Member. Most of these hominins are between 1.60 and 1.65 myr in age, but the youngest may date to only 1.53 Ma, and the oldest, to 1.75 Ma. All are 0.15-0.30 myr younger than previously estimated. The new age estimates, in conjunction with published taxonomic attributions of fossils, suggest that at least two species of Homo coexisted in the region along with A. boisei until at least 1.65 Ma. Comparison of crania KNM-ER 1813 and KNM-ER 1470, which were believed to be of comparable age, is at the focus of the debate over whether Homo habilis sensu lato is in fact composed of two species: Homo habilis and Homo rudolfensis. These two crania are separated in time by approximately 0.25 myr, and therefore, arguments for their conspecificity no longer need to confront the issue of unusually high contemporaneous variation within a single species.

  17. Influences of limb proportions and body size on locomotor kinematics in terrestrial primates and fossil hominins.

    PubMed

    Polk, J D

    2004-10-01

    During locomotion, mammalian limb postures are influenced by many factors including the animal's limb length and body mass. Polk (2002) compared the gait of similar-sized cercopithecine monkeys that differed limb proportions and found that longer-limbed monkeys usually adopt more extended joint postures than shorter-limbed monkeys in order to moderate their joint moments. Studies of primates as well as non-primate mammals that vary in body mass have demonstrated that larger animals use more extended limb postures than smaller animals. Such extended postures in larger animals increase the extensor muscle mechanical advantage and allow postures to be maintained with relatively less muscular effort (Polk, 2002; Biewener 1989). The results of these previous studies are used here to address two anthropological questions. The first concerns the postural effects of body mass and limb proportion differences between australopithecines and members of the genus Homo. That is, H. erectus and later hominins all have larger body mass and longer legs than australopithecines, and these anatomical differences suggest that Homo probably used more extended postures and probably required relatively less muscular force to resist gravity than the smaller and shorter-limbed australopithecines. The second question investigates how animals with similar size but different limb proportions differ in locomotor performance. The effects of limb proportions on gait are relevant to inferring postural and locomotor differences between Neanderthals and modern Homo sapiens which differ in their crural indices and relative limb length. This study demonstrates that primates with relatively long limbs achieve higher walking speeds while using lower stride frequencies and lower angular excursions than shorter-limbed monkeys, and these kinematic differences may allow longer-limbed taxa to locomote more efficiently than shorter-limbed species of similar mass. Such differences may also have characterized

  18. Mosaic evolution and the pattern of transitions in the hominin lineage

    PubMed Central

    Foley, Robert A.

    2016-01-01

    Humans are uniquely unique, in terms of the extreme differences between them and other living organisms, and the impact they are having on the biosphere. The evolution of humans can be seen, as has been proposed, as one of the major transitions in evolution, on a par with the origins of multicellular organisms or the eukaryotic cell (Maynard Smith & Szathmáry 1997 Major transitions in evolution). Major transitions require the evolution of greater complexity and the emergence of new evolutionary levels or processes. Does human evolution meet these conditions? I explore the diversity of evidence on the nature of transitions in human evolution. Four levels of transition are proposed—baseline, novel taxa, novel adaptive zones and major transitions—and the pattern of human evolution considered in the light of these. The primary conclusions are that changes in human evolution occur continuously and cumulatively; that novel taxa and the appearance of new adaptations are not clustered very tightly in particular periods, although there are three broad transitional phases (Pliocene, Plio-Pleistocene and later Quaternary). Each phase is distinctive, with the first based on ranging and energetics, the second on technology and niche expansion, and the third on cognition and cultural processes. I discuss whether this constitutes a ‘major transition’ in the context of the evolutionary processes more broadly; the role of behaviour in evolution; and the opportunity provided by the rich genetic, phenotypic (fossil morphology) and behavioural (archaeological) record to examine in detail major transitions and the microevolutionary patterns underlying macroevolutionary change. It is suggested that the evolution of the hominin lineage is consistent with a mosaic pattern of change. This article is part of the themed issue ‘Major transitions in human evolution’. PMID:27298474

  19. Bovid ecomorphology and hominin paleoenvironments of the Shungura Formation, lower Omo River Valley, Ethiopia.

    PubMed

    Plummer, Thomas W; Ferraro, Joseph V; Louys, Julien; Hertel, Fritz; Alemseged, Zeresenay; Bobe, René; Bishop, L C

    2015-11-01

    The Shungura Formation in the lower Omo River Valley, southern Ethiopia, has yielded an important paleontological and archeological record from the Pliocene and Pleistocene of eastern Africa. Fossils are common throughout the sequence and provide evidence of paleoenvironments and environmental change through time. This study developed discriminant function ecomorphology models that linked astragalus morphology to broadly defined habitat categories (open, light cover, heavy cover, forest, and wetlands) using modern bovids of known ecology. These models used seven variables suitable for use on fragmentary fossils and had overall classification success rates of >82%. Four hundred and one fossils were analyzed from Shungura Formation members B through G (3.4-1.9 million years ago). Analysis by member documented the full range of ecomorph categories, demonstrating that a wide range of habitats existed along the axis of the paleo-Omo River. Heavy cover ecomorphs, reflecting habitats such as woodland and heavy bushland, were the most common in the fossil sample. The trend of increasing open cover habitats from Members C through F suggested by other paleoenvironmental proxies was documented by the increase in open habitat ecomorphs during this interval. However, finer grained analysis demonstrated considerable variability in ecomorph frequencies over time, suggesting that substantial short-term variability is masked when grouping samples by member. The hominin genera Australopithecus, Homo, and Paranthropus are associated with a range of ecomorphs, indicating that all three genera were living in temporally variable and heterogeneous landscapes. Australopithecus finds were predominantly associated with lower frequencies of open habitat ecomorphs, and high frequencies of heavy cover ecomorphs, perhaps indicating a more woodland focus for this genus.

  20. Mosaic evolution and the pattern of transitions in the hominin lineage.

    PubMed

    Foley, Robert A

    2016-07-05

    Humans are uniquely unique, in terms of the extreme differences between them and other living organisms, and the impact they are having on the biosphere. The evolution of humans can be seen, as has been proposed, as one of the major transitions in evolution, on a par with the origins of multicellular organisms or the eukaryotic cell (Maynard Smith & Szathmáry 1997 Major transitions in evolution). Major transitions require the evolution of greater complexity and the emergence of new evolutionary levels or processes. Does human evolution meet these conditions? I explore the diversity of evidence on the nature of transitions in human evolution. Four levels of transition are proposed-baseline, novel taxa, novel adaptive zones and major transitions-and the pattern of human evolution considered in the light of these. The primary conclusions are that changes in human evolution occur continuously and cumulatively; that novel taxa and the appearance of new adaptations are not clustered very tightly in particular periods, although there are three broad transitional phases (Pliocene, Plio-Pleistocene and later Quaternary). Each phase is distinctive, with the first based on ranging and energetics, the second on technology and niche expansion, and the third on cognition and cultural processes. I discuss whether this constitutes a 'major transition' in the context of the evolutionary processes more broadly; the role of behaviour in evolution; and the opportunity provided by the rich genetic, phenotypic (fossil morphology) and behavioural (archaeological) record to examine in detail major transitions and the microevolutionary patterns underlying macroevolutionary change. It is suggested that the evolution of the hominin lineage is consistent with a mosaic pattern of change.This article is part of the themed issue 'Major transitions in human evolution'. © 2016 The Author(s).

  1. Genomic Signatures of Selective Pressures and Introgression from Archaic Hominins at Human Innate Immunity Genes

    PubMed Central

    Deschamps, Matthieu; Laval, Guillaume; Fagny, Maud; Itan, Yuval; Abel, Laurent; Casanova, Jean-Laurent; Patin, Etienne; Quintana-Murci, Lluis

    2016-01-01

    Human genes governing innate immunity provide a valuable tool for the study of the selective pressure imposed by microorganisms on host genomes. A comprehensive, genome-wide study of how selective constraints and adaptations have driven the evolution of innate immunity genes is missing. Using full-genome sequence variation from the 1000 Genomes Project, we first show that innate immunity genes have globally evolved under stronger purifying selection than the remainder of protein-coding genes. We identify a gene set under the strongest selective constraints, mutations in which are likely to predispose individuals to life-threatening disease, as illustrated by STAT1 and TRAF3. We then evaluate the occurrence of local adaptation and detect 57 high-scoring signals of positive selection at innate immunity genes, variation in which has been associated with susceptibility to common infectious or autoimmune diseases. Furthermore, we show that most adaptations targeting coding variation have occurred in the last 6,000–13,000 years, the period at which populations shifted from hunting and gathering to farming. Finally, we show that innate immunity genes present higher Neandertal introgression than the remainder of the coding genome. Notably, among the genes presenting the highest Neandertal ancestry, we find the TLR6-TLR1-TLR10 cluster, which also contains functional adaptive variation in Europeans. This study identifies highly constrained genes that fulfill essential, non-redundant functions in host survival and reveals others that are more permissive to change—containing variation acquired from archaic hominins or adaptive variants in specific populations—improving our understanding of the relative biological importance of innate immunity pathways in natural conditions. PMID:26748513

  2. Are humans prone to autoimmunity? Implications from evolutionary changes in hominin sialic acid biology.

    PubMed

    Varki, Ajit

    2017-09-01

    Given varied intrinsic and extrinsic challenges to the immune system, it is unsurprising that each evolutionary lineage evolves distinctive features of immunoreactivity, and that tolerance mechanisms fail, allowing autoimmunity. Humans appear prone to many autoimmune diseases, with mechanisms both genetic and environmental. Another rapidly evolving biological system involves sialic acids, a family of monosaccharides that are terminal caps on cell surface and secreted molecules of vertebrates, and play multifarious roles in immunity. We have explored multiple genomic changes in sialic acid biology that occurred in human ancestors (hominins), some with implications for enhanced immunoreactivity, and hence for autoimmunity. Human ancestors lost the enzyme synthesizing the common mammalian sialic acid Neu5Gc, with an accumulation of the precursor sialic acid Neu5Ac. Resulting changes include an enhanced reactivity by some immune cells and increased ability of macrophages to kill bacteria, at the cost of increased endotoxin sensitivity. There are also multiple human-specific evolutionary changes in inhibitory and activating Siglecs, immune cell receptors that recognize sialic acids as "self-associated molecular patterns" (SAMPs) to modulate immunity, but can also be hijacked by pathogen molecular mimicry of SAMPs. Altered expression patterns and fixed or polymorphic SIGLEC pseudogenization in humans has modulated both innate and adaptive immunity, sometimes favoring over-reactivity. Meanwhile, dietary intake of Neu5Gc (derived primarily from red meats) allows metabolic incorporation of this non-human molecule into human cells--apparently the first example of "xeno-autoimmunity" involving "xeno-autoantigen" interactions with circulating "xeno-autoantibodies". Taken together, some of these factors may contribute to the apparent human propensity for autoimmunity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Using Isotopes to Reconstruct Mammalian Diet, Migration and Paleoenvironment for Hominin Sites in Indonesia

    NASA Astrophysics Data System (ADS)

    Wershow, H.; Janssen, R.; Vonhof, H.; Lubbe, J. V. D.; Joordens, J. J.; Koutamanis, D. S.; Puspaningrum, M. R.; de Vos, J.; Reijmer, J.

    2015-12-01

    Climate plays a prominent role in ecosystem development in the biodiversity hotspot Sundaland (Malaysia and western Indonesia) throughout the Quaternary. Recurrent isolation and connection of the islands to mainland Asia due to sea level fluctuations has enabled repeated biotic migrations and encouraged genetic speciation. These migration waves also brought Homo erectus to Java. Together with extensive and well-documented collections of other terrestrial species, these hominin fossils form faunal assemblages of which the paleoenvironmental and paleogeographical background is poorly known. Using carbon, oxygen and strontium isotopes, we have reconstructed the paleoenvironmental and paleoecological conditions of several Holocene and Pleistocene fossil sites on Sumatra and Java, Indonesia. Carbon (∂13C) and oxygen (∂18O) isotope analysis of well-preserved herbivore teeth enamel reveals a marked contrast between C3-dominated diets in warmer periods, and C4-dominated diets in cooler periods, reflecting the distinct changes in Sundaland vegetation cover between glacials and interglacials. These isotope patterns allow us to assign the appropriate climatic background to some of the older fossil assemblages from Java, for which dating uncertainty does not allow direct assignment to glacial or interglacial conditions. The stable isotope signatures of herbivores from Trinil and Sangiran, sites well-known for the fossil occurrence of Homo erectus, indicate glacial conditions. The isotope data of several H. erectus fossils from these sites seem to be in line with such an interpretation. Furthermore, we applied strontium (87Sr/86Sr) isotope analyses to a sample subset. The preliminary data show distinct Sr-isotope ratios for different sites, providing clues for the applicability of this isotope technique in detecting climate-related mobility of Sundaland fossil faunas.

  4. Genomic Signatures of Selective Pressures and Introgression from Archaic Hominins at Human Innate Immunity Genes.

    PubMed

    Deschamps, Matthieu; Laval, Guillaume; Fagny, Maud; Itan, Yuval; Abel, Laurent; Casanova, Jean-Laurent; Patin, Etienne; Quintana-Murci, Lluis

    2016-01-07

    Human genes governing innate immunity provide a valuable tool for the study of the selective pressure imposed by microorganisms on host genomes. A comprehensive, genome-wide study of how selective constraints and adaptations have driven the evolution of innate immunity genes is missing. Using full-genome sequence variation from the 1000 Genomes Project, we first show that innate immunity genes have globally evolved under stronger purifying selection than the remainder of protein-coding genes. We identify a gene set under the strongest selective constraints, mutations in which are likely to predispose individuals to life-threatening disease, as illustrated by STAT1 and TRAF3. We then evaluate the occurrence of local adaptation and detect 57 high-scoring signals of positive selection at innate immunity genes, variation in which has been associated with susceptibility to common infectious or autoimmune diseases. Furthermore, we show that most adaptations targeting coding variation have occurred in the last 6,000-13,000 years, the period at which populations shifted from hunting and gathering to farming. Finally, we show that innate immunity genes present higher Neandertal introgression than the remainder of the coding genome. Notably, among the genes presenting the highest Neandertal ancestry, we find the TLR6-TLR1-TLR10 cluster, which also contains functional adaptive variation in Europeans. This study identifies highly constrained genes that fulfill essential, non-redundant functions in host survival and reveals others that are more permissive to change-containing variation acquired from archaic hominins or adaptive variants in specific populations-improving our understanding of the relative biological importance of innate immunity pathways in natural conditions. Copyright © 2016 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  5. The Advantage of Standing Up to Fight and the Evolution of Habitual Bipedalism in Hominins

    PubMed Central

    Carrier, David R.

    2011-01-01

    Background Many quadrupedal species stand bipedally on their hindlimbs to fight. This posture may provide a performance advantage by allowing the forelimbs to strike an opponent with the range of motion that is intrinsic to high-speed running, jumping, rapid braking and turning; the range of motion over which peak force and power can be produced. Methodology/Principal Findings To test the hypothesis that bipedal (i.e., orthograde) posture provides a performance advantage when striking with the forelimbs, I measured the force and energy produced when human subjects struck from “quadrupedal” (i.e., pronograde) and bipedal postures. Downward and upward directed striking energy was measured with a custom designed pendulum transducer. Side and forward strikes were measured with a punching bag instrumented with an accelerometer. When subjects struck downward from a bipedal posture the work was 43.70±12.59% (mean ± S.E.) greater than when they struck from a quadrupedal posture. Similarly, 47.49±17.95% more work was produced when subjects struck upward from a bipedal stance compared to a quadrupedal stance. Importantly, subjects did 229.69±44.19% more work in downward than upward directed strikes. During side and forward strikes the force impulses were 30.12±3.68 and 43.04±9.00% greater from a bipedal posture than a quadrupedal posture, respectively. Conclusions/Significance These results indicate that bipedal posture does provide a performance advantage for striking with the forelimbs. The mating systems of great apes are characterized by intense male-male competition in which conflict is resolved through force or the threat of force. Great apes often fight from bipedal posture, striking with both the fore- and hindlimbs. These observations, plus the findings of this study, suggest that sexual selection contributed to the evolution of habitual bipedalism in hominins. PMID:21611167

  6. On the relationships of postcanine tooth size with dietary quality and brain volume in primates: implications for hominin evolution.

    PubMed

    Jiménez-Arenas, Juan Manuel; Pérez-Claros, Juan Antonio; Aledo, Juan Carlos; Palmqvist, Paul

    2014-01-01

    Brain volume and cheek-tooth size have traditionally been considered as two traits that show opposite evolutionary trends during the evolution of Homo. As a result, differences in encephalization and molarization among hominins tend to be interpreted in paleobiological grounds, because both traits were presumably linked to the dietary quality of extinct species. Here we show that there is an essential difference between the genus Homo and the living primate species, because postcanine tooth size and brain volume are related to negative allometry in primates and show an inverse relationship in Homo. However, when size effects are removed, the negative relationship between encephalization and molarization holds only for platyrrhines and the genus Homo. In addition, there is no general trend for the relationship between postcanine tooth size and dietary quality among the living primates. If size and phylogeny effects are both removed, this relationship vanishes in many taxonomic groups. As a result, the suggestion that the presence of well-developed postcanine teeth in extinct hominins should be indicative of a poor-quality diet cannot be generalized to all extant and extinct primates.

  7. Discovering Hominins - Application of Medical Computed Tomography (CT) to Fossil-Bearing Rocks from the Site of Malapa, South Africa

    PubMed Central

    Smilg, Jacqueline S.; Berger, Lee R.

    2015-01-01

    In the South African context, computed tomography (CT) has been used applied to individually prepared fossils and small rocks containing fossils, but has not been utilized on large breccia blocks as a means of discovering fossils, and particularly fossil hominins. Previous attempts at CT imaging of rocks from other South African sites for this purpose yielded disappointing results. For this study, 109 fossil- bearing rocks from the site of Malapa, South Africa were scanned with medical CT prior to manual preparation. The resultant images were assessed for accuracy of fossil identification and characterization against the standard of manual preparation. The accurate identification of fossils, including those of early hominins, that were not visible on the surface of individual blocks, is shown to be possible. The discovery of unexpected fossils is reduced, thus lowering the potential that fossils could be damaged through accidental encounter during routine preparation, or even entirely missed. This study should significantly change the way fossil discovery, recovery and preparation is done in the South African context and has potential for application in other palaeontological situations. Medical CT imaging is shown to be reliable, readily available, cost effective and accurate in finding fossils within matrix conglomerates. Improvements in CT equipment and in CT image quality are such that medical CT is now a viable imaging modality for this palaeontological application. PMID:26684299

  8. On the Relationships of Postcanine Tooth Size with Dietary Quality and Brain Volume in Primates: Implications for Hominin Evolution

    PubMed Central

    Jiménez-Arenas, Juan Manuel; Pérez-Claros, Juan Antonio; Aledo, Juan Carlos; Palmqvist, Paul

    2014-01-01

    Brain volume and cheek-tooth size have traditionally been considered as two traits that show opposite evolutionary trends during the evolution of Homo. As a result, differences in encephalization and molarization among hominins tend to be interpreted in paleobiological grounds, because both traits were presumably linked to the dietary quality of extinct species. Here we show that there is an essential difference between the genus Homo and the living primate species, because postcanine tooth size and brain volume are related to negative allometry in primates and show an inverse relationship in Homo. However, when size effects are removed, the negative relationship between encephalization and molarization holds only for platyrrhines and the genus Homo. In addition, there is no general trend for the relationship between postcanine tooth size and dietary quality among the living primates. If size and phylogeny effects are both removed, this relationship vanishes in many taxonomic groups. As a result, the suggestion that the presence of well-developed postcanine teeth in extinct hominins should be indicative of a poor-quality diet cannot be generalized to all extant and extinct primates. PMID:24592388

  9. Rates of anterior tooth wear in Middle Pleistocene hominins from Sima de los Huesos (Sierra de Atapuerca, Spain)

    PubMed Central

    de Castro, J. M. Bermúdez; Martinón-Torres, M.; Sarmiento, S.; Lozano, M.; Arsuaga, J. L.; Carbonell, E.

    2003-01-01

    This study presents quantitative data on the rates of anterior tooth wear in a Pleistocene human population. The data were obtained for the hominin sample of the Sima de los Huesos site in Atapuerca, Spain. The fossil record belongs to a minimum of 28 individuals of the same biological population, assigned to the species Homo heidelbergensis. We have estimated the original and the preserved crown height of the mandibular incisors (I1 and I2) of 11 individuals, whose age at death can be ascertained from the mineralization stage and tooth eruption. Results provide a range of 0.276–0.348 and 0.288–0.360 mm per year for the mean wear rate of the mandibular I1 and I2, respectively, in individuals ≈16–18 years old. These data suggest that incisors' crowns would be totally worn out toward the fifth decade of life. Thus, we expect the life expectancy of this population to be seriously limited. These data, which could be contrasted with results obtained on hominins at other sites, could be of interest for estimating the death age of adult individuals. PMID:14528001

  10. Discovering Hominins - Application of Medical Computed Tomography (CT) to Fossil-Bearing Rocks from the Site of Malapa, South Africa.

    PubMed

    Smilg, Jacqueline S; Berger, Lee R

    2015-01-01

    In the South African context, computed tomography (CT) has been used applied to individually prepared fossils and small rocks containing fossils, but has not been utilized on large breccia blocks as a means of discovering fossils, and particularly fossil hominins. Previous attempts at CT imaging of rocks from other South African sites for this purpose yielded disappointing results. For this study, 109 fossil- bearing rocks from the site of Malapa, South Africa were scanned with medical CT prior to manual preparation. The resultant images were assessed for accuracy of fossil identification and characterization against the standard of manual preparation. The accurate identification of fossils, including those of early hominins, that were not visible on the surface of individual blocks, is shown to be possible. The discovery of unexpected fossils is reduced, thus lowering the potential that fossils could be damaged through accidental encounter during routine preparation, or even entirely missed. This study should significantly change the way fossil discovery, recovery and preparation is done in the South African context and has potential for application in other palaeontological situations. Medical CT imaging is shown to be reliable, readily available, cost effective and accurate in finding fossils within matrix conglomerates. Improvements in CT equipment and in CT image quality are such that medical CT is now a viable imaging modality for this palaeontological application.

  11. Taphonomic analysis of the hominin remains from Swabian Jura and their implications for the mortuary practices during the Upper Paleolithic

    NASA Astrophysics Data System (ADS)

    Sala, Nohemi; Conard, Nicholas

    2016-10-01

    The symbolic behavior of human beings usually is manifested in different ways such as figurative art, musical traditions, spoken language or complex funerary behavior. The Paleolithic sites of the Swabian Jura contain a rich archaeological record including the oldest evidence of musical instruments and figurative art which indicates complex cognitive abilities of the Paleolithic Homo sapiens that colonized Europe. Nevertheless, there is no evidence for burials in the Swabian caves during the Paleolithic. This raises questions regarding the kind of mortuary practices that existed in this region during the Paleolithic. In this paper, we address these questions from a taphonomic perspective by analyzing the hominin remains recovered in caves of the Swabian Jura. Whatever the funerary behavior was during the Early and Middle Upper Paleolithic, we have no evidence to document these practices. The Magdalenian hominin remains from Brillenhöhle, however, display anthropic modifications that have been hotly debated in the past. Our taphonomic analysis indicates that the assemblage displays traces of butchery similar to those recorded in the faunal remains. In addition to the cut marks, we have documented intentional breakage and human tooth marks, suggesting that the consumption of human corpses took place during the Magdalenian at Brillenhöhle. Similar anthropic modifications have also been documented in Magdalenian horizon at Hohle Fels. This suggests that the cannibalism practices during the Magdalenian were more common than previously expected during the Magdalenian in the Swabian Jura.

  12. Preferential access to genetic information from endogenous hominin ancient DNA and accurate quantitative SNP-typing via SPEX

    PubMed Central

    Brotherton, Paul; Sanchez, Juan J.; Cooper, Alan; Endicott, Phillip

    2010-01-01

    The analysis of targeted genetic loci from ancient, forensic and clinical samples is usually built upon polymerase chain reaction (PCR)-generated sequence data. However, many studies have shown that PCR amplification from poor-quality DNA templates can create sequence artefacts at significant levels. With hominin (human and other hominid) samples, the pervasive presence of highly PCR-amplifiable human DNA contaminants in the vast majority of samples can lead to the creation of recombinant hybrids and other non-authentic artefacts. The resulting PCR-generated sequences can then be difficult, if not impossible, to authenticate. In contrast, single primer extension (SPEX)-based approaches can genotype single nucleotide polymorphisms from ancient fragments of DNA as accurately as modern DNA. A single SPEX-type assay can amplify just one of the duplex DNA strands at target loci and generate a multi-fold depth-of-coverage, with non-authentic recombinant hybrids reduced to undetectable levels. Crucially, SPEX-type approaches can preferentially access genetic information from damaged and degraded endogenous ancient DNA templates over modern human DNA contaminants. The development of SPEX-type assays offers the potential for highly accurate, quantitative genotyping from ancient hominin samples. PMID:19864251

  13. Rates of anterior tooth wear in Middle Pleistocene hominins from Sima de los Huesos (Sierra de Atapuerca, Spain).

    PubMed

    Bermúdez de Castro, J M; Martinón-Torres, M; Sarmiento, S; Lozano, M; Arsuaga, J L; Carbonell, E

    2003-10-14

    This study presents quantitative data on the rates of anterior tooth wear in a Pleistocene human population. The data were obtained for the hominin sample of the Sima de los Huesos site in Atapuerca, Spain. The fossil record belongs to a minimum of 28 individuals of the same biological population, assigned to the species Homo heidelbergensis. We have estimated the original and the preserved crown height of the mandibular incisors (I1 and I2) of 11 individuals, whose age at death can be ascertained from the mineralization stage and tooth eruption. Results provide a range of 0.276-0.348 and 0.288-0.360 mm per year for the mean wear rate of the mandibular I1 and I2, respectively, in individuals approximately 16-18 years old. These data suggest that incisors' crowns would be totally worn out toward the fifth decade of life. Thus, we expect the life expectancy of this population to be seriously limited. These data, which could be contrasted with results obtained on hominins at other sites, could be of interest for estimating the death age of adult individuals.

  14. Hominin geographical range dynamics and relative brain size: Do non-human primates provide a good analogy?

    PubMed

    MacDonald, Katharine; Smaers, Jeroen B; Steele, James

    2015-10-01

    We use climatic and satellite remote sensing data to characterize environmental seasonality in the geographical ranges of extant non-human primates in order to assess the effect of relative brain size on tolerance of more seasonal habitats. Demonstration of such an effect in living non-human primates could provide a comparative framework for modeling hominin dispersals and geographical range dynamics in the Pliocene and Pleistocene. Our analyses found no such effect: there are neither positive nor negative correlations between relative brain size and either geographical range size or the average and range of values for environmental seasonality, whether analysed at the level of all primates, or within parvorders (strepsirrhine, catarrhine, platyrrhine). Independent analyses by other researchers comparing feeding behaviour and ecology at individual primate study sites demonstrate that in seasonal environments, the year-round metabolic costs of maintaining a relatively large brain are met by adaptive behavioural/dietary strategies. However, consistent with our own results, those comparative studies found that there was no overall association, whether positive or negative, between 'raw' environmental seasonality and primate relative brain size. We must therefore look elsewhere for a comparative model of hominin geographical range dynamics in the Pleistocene.

  15. Chronological and environmental context of the first hominin dispersal into Western Europe: The case of Barranco León (Guadix-Baza Basin, SE Spain).

    PubMed

    Agustí, Jordi; Blain, Hugues-Alexandre; Lozano-Fernández, Iván; Piñero, Pedro; Oms, Oriol; Furió, Marc; Blanco, Angel; López-García, Juan Manuel; Sala, Robert

    2015-10-01

    The early Pleistocene site of Barranco León (Guadix-Baza Basin, SE Spain), dated to 1.4 Ma (millions of years ago), records the oldest hominin occurrence in Western Europe, as evidenced by the discovery of one tooth and thousands of Mode 1 stone tools. In this paper a detailed analysis of the microvertebrate content of the D1 and D2 units from this site is presented. The early Pleistocene in the Guadix-Baza Basin is characterized by a sharp climatic deterioration, which possibly impeded the settlement of this region by the early hominin population from the southern Caucasus. Shortly afterwards, when the climatic conditions were again favorable, a hominin presence is suddenly evidenced at the units D1 and D2 of Barranco León. According to the microvertebrate analysis of these units, the mean annual temperature at the time of deposition was significantly higher than 13 °C, with prevalent humid conditions. However, although most of the species were inhabitants of water edges, an open landscape was present in the vicinity of the lake. The data reported here clearly support the idea that the early hominin occupation of Europe was strongly constrained by climatic and environmental conditions, rather than by physiography or cultural factors.

  16. Archaeogenomic insights into the adaptation of plants to the human environment: pushing plant-hominin co-evolution back to the Pliocene.

    PubMed

    Allaby, Robin G; Kistler, Logan; Gutaker, Rafal M; Ware, Roselyn; Kitchen, James L; Smith, Oliver; Clarke, Andrew C

    2015-02-01

    The colonization of the human environment by plants, and the consequent evolution of domesticated forms is increasingly being viewed as a co-evolutionary plant-human process that occurred over a long time period, with evidence for the co-evolutionary relationship between plants and humans reaching ever deeper into the hominin past. This developing view is characterized by a change in emphasis on the drivers of evolution in the case of plants. Rather than individual species being passive recipients of artificial selection pressures and ultimately becoming domesticates, entire plant communities adapted to the human environment. This evolutionary scenario leads to systems level genetic expectations from models that can be explored through ancient DNA and Next Generation Sequencing approaches. Emerging evidence suggests that domesticated genomes fit well with these expectations, with periods of stable complex evolution characterized by large amounts of change associated with relatively small selective value, punctuated by periods in which changes in one-half of the plant-hominin relationship cause rapid, low-complexity adaptation in the other. A corollary of a single plant-hominin co-evolutionary process is that clues about the initiation of the domestication process may well lie deep within the hominin lineage. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Semi-open environmental conditions during phases of hominin occupation at the Eemian Interglacial basin site Neumark-Nord 2 and its wider environment

    NASA Astrophysics Data System (ADS)

    Pop, Eduard; Bakels, Corrie

    2015-06-01

    Neandertal occupation of Eemian environments in Europe is well attested by several archaeological sites dating to this interglacial period. Does this mean that Neandertals were living in closed forest environments? Due to the potential variability of Eemian environments in space and time, it is necessary to study environmental records that can be correlated with phases of hominin presence, as reflected in the archaeological record. Such a perspective can be obtained from the small basin locality Neumark-Nord 2, as it contains an extensive and detailed environmental record, as well as a large archaeological record consisting of several distinct find levels. Analysis shows that hominin presence is predominantly associated with semi-open environmental conditions. A review of the data from the neighbouring Neumark-Nord 1 basin shows that semi-open environments were also characterizing the wider environment during phases of hominin presence at both basin localities. Large herbivores attracted to the water in these basins may have played an important role in the vegetation openness, probably in conjunction with (local) climatic conditions. The relationship between hominin presence and semi-open environments is explained as Neandertals exploiting the large herbivores aggregating around these freshwater localities, while the more varied vegetation would also have provided them with edible plant foods. Other Eemian sites from freshwater contexts provide evidence for semi-open conditions as well.

  18. Allele frequencies of human platelet antigens in Banjar, Bugis, Champa, Jawa and Kelantan Malays in Peninsular Malaysia.

    PubMed

    Wan Syafawati, W U; Norhalifah, H K; Zefarina, Z; Zafarina, Z; Panneerchelvam, S; Norazmi, M N; Chambers, G K; Edinur, H A

    2015-10-01

    The major aims of this study are to characterise and compile allelic data of human platelet antigen (HPA)-1 to -6 and -15 systems in five Malay sub-ethnic groups in Peninsular Malaysia. HPAs are polymorphic glycoproteins expressed on the surface of platelet membranes and are genetically differentiated across ethnogeographically unrelated populations. Blood samples were obtained with informed consent from 192 volunteers: Banjar (n = 30), Bugis (n = 37), Champa (n = 51), Jawa (n = 39) and Kelantan (n = 35). Genotyping was done using polymerase chain reaction-sequence specific primer method. In general, frequencies of HPAs in the Malay sub-ethnic groups are more similar to those in Asian populations compared with other more distinct populations such as Indians, Australian Aborigines and Europeans. This study provides the first HPA datasets for the selected Malay sub-ethnic groups. Subsequent analyses including previously reported HPA data of Malays, Chinese and Indians revealed details of the genetic relationships and ancestry of various sub-populations in Peninsular Malaysia. Furthermore, the comprehensive HPA allele frequency information from Peninsular Malaysia provided in this report has potential applications for future study of diseases, estimating risks associated with HPA alloimmunization and for developing an efficient HPA-typed donor recruitment strategy. © 2015 British Blood Transfusion Society.

  19. Trabecular architecture in the StW 352 fossil hominin calcaneus.

    PubMed

    Zeininger, Angel; Patel, Biren A; Zipfel, Bernhard; Carlson, Kristian J

    2016-08-01

    Australopithecus africanus has been interpreted as having a rigid lateral foot. One mechanism contributing to a rigid foot during push-off in humans is a calcaneocuboid joint (CCJ) with limited dorsiflexion and a "close-packed" talocalcaneal joint (TCJ). In contrast, apes likely have a greater CCJ range of motion and lack a close-packed TCJ. Differences in tarsal arthrokinematics may result in different joint loading environments. In Homo sapiens, we tested the hypothesis that dorsal and plantar CCJ and the TCJ show evidence of predictable habitual loading. In Pan troglodytes, Gorilla gorilla, Gorilla beringei, and Papio ursinus, we tested the hypothesis that only the dorsal CCJ shows evidence of predictable loading. Specifically, we predicted similarity in trabecular properties across the dorsal and plantar CCJ in H. sapiens, but dissimilarity in non-humans. Additionally, we investigated trabecular properties of an A. africanus calcaneus (StW 352) to evaluate joint loading patterns in this hominin and ultimately address the evolution of these properties in H. sapiens. Contrary to predictions, the H. sapiens dorsal CCJ has a significantly higher elongation index, bone volume fraction, trabecular thickness, and trabecular number than the plantar CCJ, while trabecular properties in non-humans do not always differ as predicted between regions. H. sapiens exhibits trabecular morphology indicative of less variable TCJ loading than other groups, having the most anisotropic and rod-like struts oriented in line with predicted principal loads. Multivariate analysis shows that the StW 352 dorsal CCJ matches P. ursinus best, while the plantar CCJ matches G. beringei best and the TCJ matches that of G. gorilla best. Overall patterns suggest that the StW 352 calcaneus experienced more variable loading than H. sapiens, but less variable loading than P. troglodytes, G. gorilla, G. beringei, and P. ursinus, consistent with a large range of foot movements, probably

  20. The role of carnivores and their relationship to hominin settlements in the TD6-2 level from Gran Dolina (Sierra de Atapuerca, Spain)

    NASA Astrophysics Data System (ADS)

    Saladié, Palmira; Rodríguez-Hidalgo, Antonio; Huguet, Rosa; Cáceres, Isabel; Díez, Carlos; Vallverdú, Josep; Canals, Antoni; Soto, María; Santander, Boris; Bermúdez de Castro, José María; Arsuaga, Juan Luis; Carbonell, Eudald

    2014-06-01

    Pleistocene level TD6-2 of the Gran Dolina site (Sierra de Atapuerca, Spain) is the result of anthropogenic accumulation. Hominin groups occupied the cave as a home base, where they brought in, butchered and consumed the carcasses of ungulates and other hominins. In this paper, we reassess the role of carnivores in the formation and/or modification of the assemblage. We employed different methods to explore the scenario in which the TD6-2 assemblage was formed: (1) identifying the actor responsible for tooth marks; (2) determining the frequency of carnivore tooth marks and their distribution; (3) identifying the co-occurrence of modifications (butchering marks and carnivore tooth marks); (4) calculating the percentage of change and the epiphysis to shaft ratio. Carnivore tooth marks are scarce, as is the co-occurrence of hominin and carnivore modifications. However, not all tooth marks have been attributed to a particular agent due to the high equifinality between human and carnivore tooth marks. For these reasons, the frequency of tooth marks and the co-occurrence of modifications have been of little help in interpreting the role of carnivores. Axial skeletal remains and the epiphyses of the long bones are in large part missing. The percentage of change and the epiphysis to shaft ratio suggest moderate carnivore ravaging activity. Our data indicate that the role of carnivores in TD6-2 seems to have had an impact on the original assemblage after hominins had extracted a large amount of nutrients from the carcasses. Cannibalized hominin remains showed no carnivore tooth marks and have a greater presence of low survival bones compared to ungulate remains. These findings point to a different taphonomic history suggesting that TD6-2 represents a succession of settlements having different characteristics.

  1. A fish is not a fish: patterns in fatty acid composition of aquatic food may have had implications for hominin evolution.

    PubMed

    Joordens, Josephine C A; Kuipers, Remko S; Wanink, Jan H; Muskiet, Frits A J

    2014-12-01

    From c. 2 Ma (millions of years ago) onwards, hominin brain size and cognition increased in an unprecedented fashion. The exploitation of high-quality food resources, notably from aquatic ecosystems, may have been a facilitator or driver of this phenomenon. The aim of this study is to contribute to the ongoing debate on the possible role of aquatic resources in hominin evolution by providing a more detailed nutritional context. So far, the debate has focused on the relative importance of terrestrial versus aquatic resources while no distinction has been made between different types of aquatic resources. Here we show that Indian Ocean reef fish and eastern African lake fish yield on average similarly high amounts of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA). Hence a shift from exploiting tropical marine to freshwater ecosystems (or vice versa) would entail no material difference in dietary long-chain polyunsaturated fatty acid (LC-PUFA) availability. However, a shift to marine ecosystems would likely mean a major increase in access to brain-selective micronutrients such as iodine. Fatty fish from marine temperate/cold waters yield twice as much DHA and four times as much EPA as tropical fish, demonstrating that a latitudinal shift in exploitation of African coastal ecosystems could constitute a significant difference in LC-PUFA availability with possible implications for brain development and functioning. We conclude that exploitation of aquatic food resources could have facilitated the initial moderate hominin brain increase as observed in fossils dated to c. 2 Ma, but not the exceptional brain increase in later stages of hominin evolution. We propose that the significant expansion in hominin brain size and cognition later on may have been aided by strong directional selecting forces such as runaway sexual selection of intelligence, and nutritionally supported by exploitation of high-quality food resources in stable and

  2. An updated age for the Xujiayao hominin from the Nihewan Basin, North China: Implications for Middle Pleistocene human evolution in East Asia.

    PubMed

    Ao, Hong; Liu, Chun-Ru; Roberts, Andrew P; Zhang, Peng; Xu, Xinwen

    2017-05-01

    The Xujiayao site in the Nihewan Basin (North China) is one of the most important Paleolithic sites in East Asia. Twenty Homo fossils, which were previously assigned to an archaic Homo sapiens group, have been excavated along with more than 30,000 lithic artifacts and ∼5000 mammalian fossil specimens. Dating of the Xujiayao hominin has been pursued since its excavation in the 1970s, but its age has remained controversial because of limitations of the dating techniques that have been applied to available materials. Here, we report new ages for the Xujiayao hominin based on combined electron spin resonance (ESR) dating of quartz in the sediments and high-resolution magnetostratigraphy of the fluvio-lacustrine sequence. The magnetostratigraphy suggests that the upper Matuyama and Brunhes polarity chrons are recorded at Xujiayao. The ESR dating results indicate a pooled average age of 260-370 ka for the Homo-bearing layer, which is consistent with its position within the middle Brunhes normal polarity chron indicated by magnetostratigraphy. This age estimate makes the Xujiayao hominin among the oldest mid-Pleistocene hominins with derived Neanderthal traits in East Asia. This age is consistent with the time when early Denisovans, a sister group of Neanderthals, appeared and colonized eastern Eurasia. Our updated age and the Neanderthal-like traits of the Xujiayao Homo fossils, particularly the Denisovan-like molar teeth, make it possible that the Xujiayao hominin could represent an early Denisovan. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  3. New high-resolution computed tomography data of the Taung partial cranium and endocast and their bearing on metopism and hominin brain evolution

    PubMed Central

    Holloway, Ralph L.; Broadfield, Douglas C.; Carlson, Kristian J.

    2014-01-01

    Falk and colleagues [Falk D, Zollikofer CP, Morimoto N, Ponce de León MS (2012) Proc Natl Acad Sci U S A 109(22):8467–8470] hypothesized that selective pressures favored late persistence of a metopic suture and open anterior fontanelle early in hominin evolution, and they put an emphasis on the Taung Child (Australopithecus africanus) as evidence for the antiquity of these adaptive features. They suggested three mutually nonexclusive pressures: an “obstetric dilemma,” high early postnatal brain growth rates, and neural reorganization in the frontal cortex. To test this hypothesis, we obtained the first high-resolution computed tomography (CT) data from the Taung hominin. These high-resolution image data and an examination of the hominin fossil record do not support the metopic and fontanelle features proposed by Falk and colleagues. Although a possible remnant of the metopic suture is observed in the nasion–glabella region of the Taung partial cranium (but not along the frontal crest), this character state is incongruent with the zipper model of metopic closure described by Falk and colleagues. Nor do chimpanzee and bonobo endocast data support the assertion that delayed metopic closure in Taung is necessary because of widening (reorganization) of the prefrontal or frontal cortex. These results call into question the adaptive value of delaying metopic closure, and particularly its antiquity in hominin evolution. Further data from hominoids and hominins are required to support the proposed adaptive arguments, particularly an obstetric dilemma placing constraints on neural and cranial development in Australopithecus. PMID:25157138

  4. Paleoclimatic and paleoenvironmental context of the Early Pleistocene hominins from Dmanisi (Georgia, Lesser Caucasus) inferred from the herpetofaunal assemblage

    NASA Astrophysics Data System (ADS)

    Blain, Hugues-Alexandre; Agustí, Jordi; Lordkipanidze, David; Rook, Lorenzo; Delfino, Massimo

    2014-12-01

    Dmanisi is currently the oldest Early Palaeolithic site discovered out of Africa. It has produced over 40 hominin remains, including a set of very informative skulls, in direct association with faunal remains and numerous lithic artifacts. Given the relevance of this locality, every effort is being made to reconstruct the landscapes where these hominins once lived. Amphibian and reptile remains from Dmanisi are here described for the first time and used as paleoclimatic and paleoenvironmental proxies. They comprise at least six taxa: a green toad (Bufo gr. Bufo viridis), the Greek tortoise (Testudo graeca), a green lizard (Lacerta gr. Lacerta viridis), a four-lined snake (Elaphe gr. Elaphe quatuorlineata), an indeterminate colubrid and a water snake (Natrix sp.). As these taxa are not extinct and their ecology can be directly studied, they can contribute to the reconstruction of the landscape and climate. The application of the Mutual Climatic Range method provides quantitative data indicating that during the hominin presence at Dmanisi climate was warm and dry, similar to the present-day Mediterranean climate. In comparison with today climate of Dmanisi, estimated mean annual temperature was 3.1 °C higher, with a greater increase of temperature in summer (+7.1 °C) than in winter (+4.7 °C). The mean annual precipitation was slightly lower (-65 mm) than the current level, with precipitation higher than current one during winter (+104 mm) but strongly lower during the other seasons, suggesting a stronger contrast in the rainfall regime during the year. From a paleoenvironmental point of view, fossil amphibians and reptiles all suggest the predominance of arid environments, from steppe or semi-desert to open Mediterranean forest, with stony or rocky substrate and bushy areas. The presence of permanent aquatic environments is also documented. These results mainly agree with those for large mammals, small mammals and the archaeobotanical analysis that indicate an

  5. Preserving the Impossible: Conservation of Soft-Sediment Hominin Footprint Sites and Strategies for Three-Dimensional Digital Data Capture

    PubMed Central

    Bennett, Matthew R.; Falkingham, Peter; Morse, Sarita A.; Bates, Karl; Crompton, Robin H.

    2013-01-01

    Human footprints provide some of the most publically emotive and tangible evidence of our ancestors. To the scientific community they provide evidence of stature, presence, behaviour and in the case of early hominins potential evidence with respect to the evolution of gait. While rare in the geological record the number of footprint sites has increased in recent years along with the analytical tools available for their study. Many of these sites are at risk from rapid erosion, including the Ileret footprints in northern Kenya which are second only in age to those at Laetoli (Tanzania). Unlithified, soft-sediment footprint sites such these pose a significant geoconservation challenge. In the first part of this paper conservation and preservation options are explored leading to the conclusion that to ‘record and digitally rescue’ provides the only viable approach. Key to such strategies is the increasing availability of three-dimensional data capture either via optical laser scanning and/or digital photogrammetry. Within the discipline there is a developing schism between those that favour one approach over the other and a requirement from geoconservationists and the scientific community for some form of objective appraisal of these alternatives is necessary. Consequently in the second part of this paper we evaluate these alternative approaches and the role they can play in a ‘record and digitally rescue’ conservation strategy. Using modern footprint data, digital models created via optical laser scanning are compared to those generated by state-of-the-art photogrammetry. Both methods give comparable although subtly different results. This data is evaluated alongside a review of field deployment issues to provide guidance to the community with respect to the factors which need to be considered in digital conservation of human/hominin footprints. PMID:23613743

  6. Orangutan fish eating, primate aquatic fauna eating, and their implications for the origins of ancestral hominin fish eating.

    PubMed

    Russon, Anne E; Compost, Alain; Kuncoro, Purwo; Ferisa, Agnes

    2014-12-01

    This paper presents new evidence of fish eating in rehabilitant orangutans living on two Bornean islands and explores its contributions to understanding nonhuman primates' aquatic fauna eating and the origins of ancestral hominin fish eating. We assessed the prevalence of orangutans' fish eating, their techniques for obtaining fish, and possible contributors (ecology, individual differences, humans). We identified 61 events in which orangutans tried to obtain fish, including 19 in which they ate fish. All the orangutans were juvenile-adolescent; all the fish were disabled catfish; and most were obtained and eaten in drier seasons in or near shallow, slow-moving water. Orangutans used several techniques to obtain fish (inadvertent, opportunistic and deliberate hand-catch, scrounge, tool-assisted catch) and probably learned them in that order. Probable contributing factors were orangutan traits (age, pre-existing water or tool skills), island features (social density, water accessibility), and local human fishing. Our review of primates' aquatic fauna eating showed orangutans to be one of 20 species that eat aquatic fauna, one of nine confirmed to eat fish, and one of three that use tools to obtain fish. Primate fish eating is also site-specific within species, partly as a function of habitat (e.g., marine-freshwater, seasonality) and human influence (possibly fostered eating fish or other aquatic fauna at most sites, clearly induced it at some). At tropical freshwater sites, fish eating occurred most often in drier seasons around shallow water. Orangutan and primate findings are generally consistent with Stewart's (2010) reconstruction of the origins of ancestral hominin fish eating, but suggest that it, and tool-assisted fish catching, were possible much earlier.

  7. Accessing developmental information of fossil hominin teeth using new synchrotron microtomography-based visualization techniques of dental surfaces and interfaces.

    PubMed

    Le Cabec, Adeline; Tang, Nancy; Tafforeau, Paul

    2015-01-01

    Quantification of dental long-period growth lines (Retzius lines in enamel and Andresen lines in dentine) and matching of stress patterns (internal accentuated lines and hypoplasias) are used in determining crown formation time and age at death in juvenile fossil hominins. They yield the chronology employed for inferences of life history. Synchrotron virtual histology has been demonstrated as a non-destructive alternative to conventional invasive approaches. Nevertheless, fossil teeth are sometimes poorly preserved or physically inaccessible, preventing observation of the external expression of incremental lines (perikymata and periradicular bands). Here we present a new approach combining synchrotron virtual histology and high quality three-dimensional rendering of dental surfaces and internal interfaces. We illustrate this approach with seventeen permanent fossil hominin teeth. The outer enamel surface and enamel-dentine junction (EDJ) were segmented by capturing the phase contrast fringes at the structural interfaces. Three-dimensional models were rendered with Phong's algorithm, and a combination of directional colored lights to enhance surface topography and the pattern of subtle variations in tissue density. The process reveals perikymata and linear enamel hypoplasias on the entire crown surface, including unerupted teeth. Using this method, highly detailed stress patterns at the EDJ allow precise matching of teeth within an individual's dentition when virtual histology is not sufficient. We highlight that taphonomical altered enamel can in particular cases yield artificial subdivisions of perikymata when imaged using X-ray microtomography with insufficient resolution. This may complicate assessments of developmental time, although this can be circumvented by a careful analysis of external and internal structures in parallel. We further present new crown formation times for two unerupted canines from South African Australopiths, which were found to form over

  8. Preserving the impossible: conservation of soft-sediment hominin footprint sites and strategies for three-dimensional digital data capture.

    PubMed

    Bennett, Matthew R; Falkingham, Peter; Morse, Sarita A; Bates, Karl; Crompton, Robin H

    2013-01-01

    Human footprints provide some of the most publically emotive and tangible evidence of our ancestors. To the scientific community they provide evidence of stature, presence, behaviour and in the case of early hominins potential evidence with respect to the evolution of gait. While rare in the geological record the number of footprint sites has increased in recent years along with the analytical tools available for their study. Many of these sites are at risk from rapid erosion, including the Ileret footprints in northern Kenya which are second only in age to those at Laetoli (Tanzania). Unlithified, soft-sediment footprint sites such these pose a significant geoconservation challenge. In the first part of this paper conservation and preservation options are explored leading to the conclusion that to 'record and digitally rescue' provides the only viable approach. Key to such strategies is the increasing availability of three-dimensional data capture either via optical laser scanning and/or digital photogrammetry. Within the discipline there is a developing schism between those that favour one approach over the other and a requirement from geoconservationists and the scientific community for some form of objective appraisal of these alternatives is necessary. Consequently in the second part of this paper we evaluate these alternative approaches and the role they can play in a 'record and digitally rescue' conservation strategy. Using modern footprint data, digital models created via optical laser scanning are compared to those generated by state-of-the-art photogrammetry. Both methods give comparable although subtly different results. This data is evaluated alongside a review of field deployment issues to provide guidance to the community with respect to the factors which need to be considered in digital conservation of human/hominin footprints.

  9. Accessing Developmental Information of Fossil Hominin Teeth Using New Synchrotron Microtomography-Based Visualization Techniques of Dental Surfaces and Interfaces

    PubMed Central

    Le Cabec, Adeline; Tang, Nancy; Tafforeau, Paul

    2015-01-01

    Quantification of dental long-period growth lines (Retzius lines in enamel and Andresen lines in dentine) and matching of stress patterns (internal accentuated lines and hypoplasias) are used in determining crown formation time and age at death in juvenile fossil hominins. They yield the chronology employed for inferences of life history. Synchrotron virtual histology has been demonstrated as a non-destructive alternative to conventional invasive approaches. Nevertheless, fossil teeth are sometimes poorly preserved or physically inaccessible, preventing observation of the external expression of incremental lines (perikymata and periradicular bands). Here we present a new approach combining synchrotron virtual histology and high quality three-dimensional rendering of dental surfaces and internal interfaces. We illustrate this approach with seventeen permanent fossil hominin teeth. The outer enamel surface and enamel-dentine junction (EDJ) were segmented by capturing the phase contrast fringes at the structural interfaces. Three-dimensional models were rendered with Phong’s algorithm, and a combination of directional colored lights to enhance surface topography and the pattern of subtle variations in tissue density. The process reveals perikymata and linear enamel hypoplasias on the entire crown surface, including unerupted teeth. Using this method, highly detailed stress patterns at the EDJ allow precise matching of teeth within an individual’s dentition when virtual histology is not sufficient. We highlight that taphonomical altered enamel can in particular cases yield artificial subdivisions of perikymata when imaged using X-ray microtomography with insufficient resolution. This may complicate assessments of developmental time, although this can be circumvented by a careful analysis of external and internal structures in parallel. We further present new crown formation times for two unerupted canines from South African Australopiths, which were found to form

  10. Toros-Menalla (Chad, 7 Ma), the earliest hominin-bearing area: How many mammal paleocommunities?

    PubMed

    Le Fur, Soizic; Fara, Emmanuel; Mackaye, Hassane Taïsso; Vignaud, Patrick; Brunet, Michel

    2014-04-01

    The fossiliferous area of Toros-Menalla (TM) (Djurab Desert, northern Chad) has yielded one of the richest African mammal faunas of the late Miocene. It is also the place where the earliest known hominin, Sahelanthropus tchadensis, was found. Although more than 300 localities are recorded in that area, previous paleoecological studies focused only on the largest and richest one. The integration of the material from other TM localities, and thus of a significant number of mammal taxa, is crucial to improve the corresponding paleoenvironmental reconstructions. Before such inferences can be drawn, it is necessary to test for the ecological integrity of these mammal assemblages: how many paleocommunities do they represent? The faunal structures of several assemblages selected for their apparent resilience to sampling biases are compared here. The criteria used in the inter-assemblage comparison are ecological diversity, taxonomic structure (taxonomic rank of abundance) and taxonomic composition. Based on multivariate analyses, two groups of TM assemblages can be distinguished. One of them contains the hominin-bearing assemblages. It is taxonomically richer and shows a wider ecological spectrum than its counterpart. The degree of taphonomic alteration undergone by the TM assemblages, as well as the distribution of amphibious mammals among them, suggest different depositional settings for these two groups of assemblages, the richest of which was probably associated with lower hydraulic energy. Overall, it seems that the TM assemblages recorded the same mammal paleocommunity preserved in two contrasted depositional settings. Moreover, the spatial overlap of these assemblages provides further evidence for the mosaic character of the landscape associated with S. tchadensis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Neurocranium versus Face: A Morphometric Approach with Classical Anthropometric Variables for Characterizing Patterns of Cranial Integration in Extant Hominoids and Extinct Hominins.

    PubMed

    Pérez-Claros, Juan Antonio; Jiménez-Arenas, Juan Manuel; Palmqvist, Paul

    2015-01-01

    The relative importance of the two main cranial complexes, the neurocranium and the splanchnocranium, has been examined in the five species of extant hominoids and in a huge sample of extinct hominins using six standard craniometric variables that measure the length, width and height of each cranial module. Factor analysis and two-block partial least squares were used for establishing the major patterns of developmental and evolutionary integration between both cranial modules. The results obtained show that all extant hominoids (including the anatomically modern humans) share a conserved pattern of developmental integration, a result that agrees with previous studies. The pattern of evolutionary integration between both cranial modules in australopiths runs in parallel to developmental integration. In contrast, the pattern of evolutionary and developmental integration of the species of the genus Homo is the opposite, which is probably the consequence of distinctive selective regimes for both hominin groups.

  12. Neurocranium versus Face: A Morphometric Approach with Classical Anthropometric Variables for Characterizing Patterns of Cranial Integration in Extant Hominoids and Extinct Hominins

    PubMed Central

    Pérez-Claros, Juan Antonio; Jiménez-Arenas, Juan Manuel; Palmqvist, Paul

    2015-01-01

    The relative importance of the two main cranial complexes, the neurocranium and the splanchnocranium, has been examined in the five species of extant hominoids and in a huge sample of extinct hominins using six standard craniometric variables that measure the length, width and height of each cranial module. Factor analysis and two-block partial least squares were used for establishing the major patterns of developmental and evolutionary integration between both cranial modules. The results obtained show that all extant hominoids (including the anatomically modern humans) share a conserved pattern of developmental integration, a result that agrees with previous studies. The pattern of evolutionary integration between both cranial modules in australopiths runs in parallel to developmental integration. In contrast, the pattern of evolutionary and developmental integration of the species of the genus Homo is the opposite, which is probably the consequence of distinctive selective regimes for both hominin groups. PMID:26177535

  13. Hominins without fellow travellers? First appearances and inferred dispersals of Afro-Eurasian large-mammals in the Plio-Pleistocene

    NASA Astrophysics Data System (ADS)

    O'Regan, H. J.; Turner, A.; Bishop, L. C.; Elton, S.; Lamb, A. L.

    2011-06-01

    Discoveries of fossil Homo outside Africa predating 1.0 Ma have generated much discussion about hominin dispersal routes. However, tool-using bipeds were only one element of the inter-continental mammalian dispersals that occurred during the climatic changes of the Pliocene and Pleistocene. This paper will place hominin movements in the context of those of the wider mammalian fauna, which includes carnivores, bovids and non-human primates. The distribution of these different taxa suggests that species moved individually when the environmental conditions were right for them, rather than in multi-species waves of dispersal, and allows evaluation of the contextual evidence for the newly emerging 'Out of Asia' paradigm as well as the established 'Out of Africa' model.

  14. New Radiometric Ages for the BH-1 Hominin from Balanica (Serbia): Implications for Understanding the Role of the Balkans in Middle Pleistocene Human Evolution

    PubMed Central

    Rink, William J.; Mercier, Norbert; Mihailović, Dušan; Morley, Mike W.; Thompson, Jeroen W.; Roksandic, Mirjana

    2013-01-01

    Newly obtained ages, based on electron spin resonance combined with uranium series isotopic analysis, and infrared/post-infrared luminescence dating, provide a minimum age that lies between 397 and 525 ka for the hominin mandible BH-1 from Mala Balanica cave, Serbia. This confirms it as the easternmost hominin specimen in Europe dated to the Middle Pleistocene. Inferences drawn from the morphology of the mandible BH-1 place it outside currently observed variation of European Homo heidelbergensis. The lack of derived Neandertal traits in BH-1 and its contemporary specimens in Southeast Europe, such as Kocabaş, Vasogliano and Ceprano, coupled with Middle Pleistocene synapomorphies, suggests different evolutionary forces acting in the east of the continent where isolation did not play such an important role during glaciations. PMID:23405085

  15. Papio Cranium from the Hominin-Bearing Site of Malapa: Implications for the Evolution of Modern Baboon Cranial Morphology and South African Plio-Pleistocene Biochronology

    PubMed Central

    Gilbert, Christopher C.; Steininger, Christine M.; Kibii, Job M.; Berger, Lee R.

    2015-01-01

    A new partial cranium (UW 88-886) of the Plio-Pleistocene baboon Papio angusticeps from Malapa is identified, described and discussed. UW 88-886 represents the only non-hominin primate yet recovered from Malapa and is important both in the context of baboon evolution as well as South African hominin site biochronology. The new specimen may represent the first appearance of modern baboon anatomy and coincides almost perfectly with molecular divergence date estimates for the origin of the modern P. hamadryas radiation. The fact that the Malapa specimen is dated between ~2.026–2.36 million years ago (Ma) also has implications for the biochronology of other South African Plio-Pleistocene sites where P. angusticeps is found. PMID:26287673

  16. Diet and environment 1.2 million years ago revealed through analysis of dental calculus from Europe's oldest hominin at Sima del Elefante, Spain

    NASA Astrophysics Data System (ADS)

    Hardy, Karen; Radini, Anita; Buckley, Stephen; Blasco, Ruth; Copeland, Les; Burjachs, Francesc; Girbal, Josep; Yll, Riker; Carbonell, Eudald; Bermúdez de Castro, Jose María

    2017-02-01

    Sima del Elefante, Atapuerca, Spain contains one of the earliest hominin fragments yet known in Europe, dating to 1.2 Ma. Dental calculus from a hominin molar was removed, degraded and analysed to recover entrapped remains. Evidence for plant use at this time is very limited and this study has revealed the earliest direct evidence for foods consumed in the genus Homo. This comprises starchy carbohydrates from two plants, including a species of grass from the Triticeae or Bromideae tribe, meat and plant fibres. All food was eaten raw, and there is no evidence for processing of the starch granules which are intact and undamaged. Additional biographical detail includes fragments of non-edible wood found adjacent to an interproximal groove suggesting oral hygiene activities, while plant fibres may be linked to raw material processing. Environmental evidence comprises spores, insect fragments and conifer pollen grains which are consistent with a forested environment.

  17. New radiometric ages for the BH-1 hominin from Balanica (Serbia): implications for understanding the role of the Balkans in Middle Pleistocene human evolution.

    PubMed

    Rink, William J; Mercier, Norbert; Mihailović, Dušan; Morley, Mike W; Thompson, Jeroen W; Roksandic, Mirjana

    2013-01-01

    Newly obtained ages, based on electron spin resonance combined with uranium series isotopic analysis, and infrared/post-infrared luminescence dating, provide a minimum age that lies between 397 and 525 ka for the hominin mandible BH-1 from Mala Balanica cave, Serbia. This confirms it as the easternmost hominin specimen in Europe dated to the Middle Pleistocene. Inferences drawn from the morphology of the mandible BH-1 place it outside currently observed variation of European Homo heidelbergensis. The lack of derived Neandertal traits in BH-1 and its contemporary specimens in Southeast Europe, such as Kocabaş, Vasogliano and Ceprano, coupled with Middle Pleistocene synapomorphies, suggests different evolutionary forces acting in the east of the continent where isolation did not play such an important role during glaciations.

  18. Diet and environment 1.2 million years ago revealed through analysis of dental calculus from Europe's oldest hominin at Sima del Elefante, Spain.

    PubMed

    Hardy, Karen; Radini, Anita; Buckley, Stephen; Blasco, Ruth; Copeland, Les; Burjachs, Francesc; Girbal, Josep; Yll, Riker; Carbonell, Eudald; Bermúdez de Castro, Jose María

    2017-02-01

    Sima del Elefante, Atapuerca, Spain contains one of the earliest hominin fragments yet known in Europe, dating to 1.2 Ma. Dental calculus from a hominin molar was removed, degraded and analysed to recover entrapped remains. Evidence for plant use at this time is very limited and this study has revealed the earliest direct evidence for foods consumed in the genus Homo. This comprises starchy carbohydrates from two plants, including a species of grass from the Triticeae or Bromideae tribe, meat and plant fibres. All food was eaten raw, and there is no evidence for processing of the starch granules which are intact and undamaged. Additional biographical detail includes fragments of non-edible wood found adjacent to an interproximal groove suggesting oral hygiene activities, while plant fibres may be linked to raw material processing. Environmental evidence comprises spores, insect fragments and conifer pollen grains which are consistent with a forested environment.

  19. Papio Cranium from the Hominin-Bearing Site of Malapa: Implications for the Evolution of Modern Baboon Cranial Morphology and South African Plio-Pleistocene Biochronology.

    PubMed

    Gilbert, Christopher C; Steininger, Christine M; Kibii, Job M; Berger, Lee R

    2015-01-01

    A new partial cranium (UW 88-886) of the Plio-Pleistocene baboon Papio angusticeps from Malapa is identified, described and discussed. UW 88-886 represents the only non-hominin primate yet recovered from Malapa and is important both in the context of baboon evolution as well as South African hominin site biochronology. The new specimen may represent the first appearance of modern baboon anatomy and coincides almost perfectly with molecular divergence date estimates for the origin of the modern P. hamadryas radiation. The fact that the Malapa specimen is dated between ~2.026-2.36 million years ago (Ma) also has implications for the biochronology of other South African Plio-Pleistocene sites where P. angusticeps is found.

  20. Intra-individual metameric variation expressed at the enamel-dentine junction of lower post-canine dentition of South African fossil hominins and modern humans.

    PubMed

    Pan, Lei; Thackeray, John Francis; Dumoncel, Jean; Zanolli, Clément; Oettlé, Anna; de Beer, Frikkie; Hoffman, Jakobus; Duployer, Benjamin; Tenailleau, Christophe; Braga, José

    2017-08-01

    The aim of this study is to compare the degree and patterning of inter- and intra-individual metameric variation in South African australopiths, early Homo and modern humans. Metameric variation likely reflects developmental and taxonomical issues, and could also be used to infer ecological and functional adaptations. However, its patterning along the early hominin postcanine dentition, particularly among South African fossil hominins, remains unexplored. Using microfocus X-ray computed tomography (µXCT) and geometric morphometric tools, we studied the enamel-dentine junction (EDJ) morphology and we investigated the intra- and inter-individual EDJ metameric variation among eight australopiths and two early Homo specimens from South Africa, as well as 32 modern humans. Along post-canine dentition, shape changes between metameres represented by relative positions and height of dentine horns, outlines of the EDJ occlusal table are reported in modern and fossil taxa. Comparisons of EDJ mean shapes and multivariate analyses reveal substantial variation in the direction and magnitude of metameric shape changes among taxa, but some common trends can be found. In modern humans, both the direction and magnitude of metameric shape change show increased variability in M2 -M3 compared to M1 -M2 . Fossil specimens are clustered together showing similar magnitudes of shape change. Along M2 -M3 , the lengths of their metameric vectors are not as variable as those of modern humans, but they display considerable variability in the direction of shape change. The distalward increase of metameric variation along the modern human molar row is consistent with the odontogenetic models of molar row structure (inhibitory cascade model). Though much remains to be tested, the variable trends and magnitudes in metamerism in fossil hominins reported here, together with differences in the scale of shape change between modern humans and fossil hominins may provide valuable information regarding

  1. The environment of the Ethiopian highlands at the Mid Pleistocene Transition: Fauna, flora and hominins in the 850-700 ka sequence of Gombore II (Melka Kunture)

    NASA Astrophysics Data System (ADS)

    Mussi, M.; Altamura, F.; Bonnefille, R.; De Rita, D.; Melis, R. T.

    2016-10-01

    Environment, climatic change and human evolution have been debated over the last 50 years giving special attention to the Plio-Pleistocene sites of the Rift Valley. In this paper we discuss the environment and the limits of hominin adaptability based on evidence from Melka Kunture, at 2000 m asl on the Ethiopian highlands, and specifically on the ∼850 ka to ∼700 ka sequence at sub-site Gombore II. Human fossils and multiple Acheulean occurrences, as well as hippo remains and footprints, combined with palynological analysis, provide a highly detailed chronological resolution of the changing local environmental conditions during the last ∼150 ka of the MPT (Mid Pleistocene Transition), including the sequence of events after a volcanic eruption. Layers containing footprints and fossils are evidence of near-continuous occupation by hippos and their recolonization of the area after a disruptive volcanic eruption. Conversely, Acheulean implements and human fossils suggest that peopling by hominins occurred at a different and discontinuous pace even when the flora and fauna were re-established and the environment was rather stable. Most notably, the assembled evidence points to the limits of Homo erectus s.l. adaptability. Apparently, this hominin could no longer live at 2000 m asl when the climate deteriorated during glacial isotopic stage 20, becoming markedly colder than it is today, but re-colonized the area when the climate turned warmer again during isotopic stage 19.

  2. A description of the geological context, discrete traits, and linear morphometrics of the Middle Pleistocene hominin from Dali, Shaanxi Province, China.

    PubMed

    Wu, Xinzhi; Athreya, Sheela

    2013-01-01

    In 1978, a nearly complete hominin fossil cranium was recovered from loess deposits at the site of Dali in Shaanxi Province, northwestern China. It was subsequently briefly described in both English and Chinese publications. Here we present a comprehensive univariate and nonmetric description of the specimen and provide comparisons with key Middle Pleistocene Homo erectus and non-erectus hominins from Eurasia and Africa. In both respects we find affinities with Chinese H. erectus as well as African and European Middle Pleistocene hominins typically referred to as Homo heidelbergensis. Specifically, the Dali specimen possesses a low cranial height, relatively short and arched parietal bones, an angled occipital bone, and a nonprominent articular tubercle relative to the preglenoid surface all of which distinguish it from Afro/European Middle Pleistocene Homo and align it with Asian H. erectus. At the same time, it displays a more derived morphology of the supraorbital torus and supratoral sulcus and a thinner tympanic plate than H. erectus, a relatively long upper (lambda-inion) occipital plane with a clear separation of inion and opisthocranion, and an absolute and relative increase in brain size, all of which align it with African and European Middle Pleistocene Homo. Finally, traits such as the form of the frontal keel and the relatively short, broad midface align Dali specifically with other Chinese specimens from the Middle Pleistocene and Late Pleistocene, including H. erectus, and differentiate these from the Afro/European specimens of this time period. Copyright © 2012 Wiley Periodicals, Inc.

  3. Lower Paleolithic hominin ecology at the fringe of the desert: Faunal remains from Bizat Ruhama and Nahal Hesi, Northern Negev, Israel.

    PubMed

    Yeshurun, Reuven; Zaidner, Yossi; Eisenmann, Véra; Martínez-Navarro, Bienvenido; Bar-Oz, Guy

    2011-04-01

    The Southern Levant is a pivotal area for the study of hominin paleoecology during the Lower Paleolithic, because of its location on the out-of-Africa dispersal route and its significant ecological diversity. Important information has been gained by archaeofaunal studies, which usually reveal that exploitation of diverse Mediterranean environments with woodlands, marshes and lake margins, represents a dominant subsistence strategy for Lower Paleolithic hominins. Here, we present new taxonomic and taphonomic data from two sites in the southern coastal plain of the Southern Levant, at the fringe of the Negev Desert: Bizat Ruhama (Early Pleistocene) and Nahal Hesi (Middle Pleistocene). The sites preserve anthropogenic faunas, with the former signaling a marrow-exploitation strategy, perhaps related to scavenging from carnivore kills, and the latter showing evidence for primary access to fleshed ungulate carcasses. The species composition of these Northern Negev sites is unique for the Levantine Lower Paleolithic in that these sites lack typical woodland and riparian species, probably indicating an open, relatively uniform environment with patchy water sources and trees, much like this semiarid region today. Bizat Ruhama and Nahal Hesi are among the only Levantine Lower Paleolithic faunas associated with such a setting, thereby widening the known spectrum of environments exploited by hominins in the region. It is suggested that the two sites, coupled with the nearby Late Pleistocene evidence, reflect a largely stable semiarid environment on the northwestern fringe of the Negev Desert throughout much of the Pleistocene. Copyright © 2010. Published by Elsevier Ltd.

  4. Was FLK North levels 1-2 a classic ``living floor'' of Oldowan hominins or a taphonomically complex palimpsest dominated by large carnivore feeding behavior?

    NASA Astrophysics Data System (ADS)

    Bunn, H. T.; Mabulla, A. Z. P.; Domínguez-Rodrigo, M.; Ashley, G. M.; Barba, R.; Diez-Martín, F.; Remer, K.; Yravedra, J.; Baquedano, E.

    2010-11-01

    From excavation at FLK North levels 1-2 in 1960-1962, Mary Leakey reported approximately 1200 Oldowan artifacts and 3300 large mammal fossils as a hominin "living floor". Preliminary taphonomic analysis by Bunn seemed supportive, based on the presence of some cut-marked bones, the concentration of several dozen bovid individuals, and the relative abundance of limbs and mandibles over other axial elements. Recent taphonomic analysis of Leakey's entire fossil assemblage by Domínguez-Rodrigo and Barba, however, documents a minor hominin role at the site, contrasted to the dominant role of carnivores. Felids brought prey animals; hyenas scavenged from abandoned felid meals. At different times, hominins butchered several bovids and discarded artifacts at this dynamic location. Since 2006, renewed excavations at FLK North and other sites by the Olduvai Paleoanthropology and Paleoecology Project (TOPPP) have expanded artifact and fossil samples and implemented new analytical approaches to clarify taphonomic histories of the Olduvai paleolandscape. At FLK North, > 1000 new large mammal fossils from levels 1 to 2 show minimal butchery evidence amid abundant evidence of carnivore gnawing/fracture, rodent gnawing, and sediment abrasion. To help guide future excavation and analyses, we have developed several alternative working hypotheses of site formation.

  5. The Acheulian site of Gesher Benot Ya'aqov, Israel: environment, hominin culture, subsistence and adaptation on the shores of the paleo-Hula Lake

    NASA Astrophysics Data System (ADS)

    Goren-Inbar, N.

    2014-12-01

    The Acheulian site of Gesher Benot Ya'aqov (GBY), located in the Hula Valley, northern sector of the Dead Sea transform, stretches along 3.5 km of the Jordan River and its banks. The accumulation of tilted lake-margin sediments interfingered with basalt flows began 1.1 Ma and ended after 0.6 Ma. The excavations (1989-1997) exposed 34 m thick deposits that provide unique data sets on climate, environment, biology, culture and hominin behavior. Hominin presence is known throughout the sequence, providing information on Acheulian technology and cognition along the time trajectory, but the richest sites (15 in number) occur above the M/B Chron Boundary. Reconstructions of paleoenvironment and habitats are based on fossil remains yielding an extremely rich typically Mediterranean biomass of diverse biogeographic origins. Macro and micro organic material (over 140 identified taxa) exhibits a typical Mediterranean environment similar to the extant flora, with few extinctions (20 species). The rich fossil faunal include molluscs, ostracods, fish, amphibians, reptiles, birds, micromammals and medium-sized to large mammals (over 237 taxa), predominantly Palearctic in biogeographic origin. Many of these taxa are still extant, attesting to stable habitats and paleoclimatic conditions. Hominin occupations are documented by thousands of lithic artifacts (flint, limestone and basalt), all assigned to the Large Flake Acheulian culture. These assemblages show a continuous cultural tradition of the same tool kit along the time trajectory. The lithic reduction required developed cognitive abilities and communication abilities, interpreted as language. Evidence of hominin subsistence includes data on carcass processing including extraction of marrow, with a preference for consumption of fallow deer, elephant, hippopotamus and fish. Edible plant remains include nuts, USO, fruits, seeds and vegetables in association with stone artifacts and animal bones. Fire, present throughout, was

  6. The ICDP-Hominin Sites and Paleolakes Drilling Project (HSPDP): new data from the Chew Bahir site in Ethiopia

    NASA Astrophysics Data System (ADS)

    Leng, Melanie; Dean, Jonathan; Asrat, Asfawossen; Cohen, Andrew; Foerster, Verena; Just, Janna; Klasen, Nicole; Lamb, Henry; Schäbitz, Frank; Trauth, Martin; Viehberg, Finn; Wagner, Bernd

    2016-04-01

    There are currently few long, continuous, Pleistocene records from East Africa, meaning it has been difficult to establish the relative influence of low- versus high-latitude forcing on East African climate and climatic conditions at the time of anatomically modern human origin and subsequent dispersal. We have been attempting to address these gaps in our knowledge by analysing lake sediments taken from Chew Bahir, an area of playa mudflats in southern Ethiopia close to the site of the oldest-known anatomically modern human fossils at Omo-Kibish. In March 2014, Chew Bahir was cored to a depth of ~40 metres, and the resulting sediment sequence is estimated to cover the last ~115ka. In December 2014, a nearby site was drilled to a depth of ~280 metres as part of the International Continental scientific Drilling Programme - Hominin Sites and Paleolakes Drilling Project (HSPDP). The oxygen and carbon isotope composition of endogenic calcite and other data from these cores will be presented. The data show some significant changes in water balance variability, the period prior to 70ka appears very unstable with some significant periods of drought and flood. Between 70-20ka the lake was stable and evaporative. The last 20ka years was wetter.

  7. Tool-composite reuse in wild chimpanzees (Pan troglodytes): archaeologically invisible steps in the technological evolution of early hominins?

    PubMed

    Carvalho, Susana; Biro, Dora; McGrew, William C; Matsuzawa, Tetsuro

    2009-10-01

    Recent etho-archaeological studies of stone-tool use by wild chimpanzees have contributed valuable data towards elucidating the variables that influenced the emergence and development of the first lithic industries among Plio-Pleistocene hominins. Such data help to identify potential behaviours entailed in the first percussive technologies that are invisible in archaeological records. The long-term research site of Bossou in Guinea features a unique chimpanzee community whose members systematically use portable stones as hammers and anvils to crack open nuts in natural as well as in field experimental settings. Here we present the first analysis of repeated reuse of the same tool-composites in wild chimpanzees. Data collected over 5 years of experimental nut-cracking sessions at an "outdoor laboratory" site were assessed for the existence of systematic patterns in the selection of tool-composites, at group and at individual levels. Chimpanzees combined certain stones as hammer and anvil more often than expected by chance, even when taking into account preferences for individual stones by themselves. This may reflect an ability to recognise the nut-cracker as a single tool (composed of two elements, but functional only as a whole), as well as discrimination of tool quality-effectiveness. Through repeatedly combining the same pairs of stones--whether due to preferences for particular composites or for the two elements independently--tool-users may amplify use-wear traces and increase the likelihood of fracturing the stones, and thus of detaching pieces by battering.

  8. The first evidence of cut marks and usewear traces from the Plio-Pleistocene locality of El-Kherba (Ain Hanech), Algeria: implications for early hominin subsistence activities circa 1.8 Ma.

    PubMed

    Sahnouni, Mohamed; Rosell, Jordi; van der Made, Jan; Vergès, Josep María; Ollé, Andreu; Kandi, Nadia; Harichane, Zoheir; Derradji, Abdelkader; Medig, Mohamed

    2013-02-01

    The current archaeological data on early hominin subsistence activities in Africa are derived chiefly from Sub-Saharan Plio-Pleistocene sites. The recent studies at El-Kherba (Ain Hanech) in northeastern Algeria expand the geographic range of evidence of hominin subsistence patterns to include the earliest known archaeological sites documented in North Africa. Dated to 1.78 million years ago (Ma), excavations from El-Kherba yielded an Oldowan industry associated with a savanna-like fauna contained in floodplain deposits. The faunal assemblage is dominated by large and medium-sized animals (mainly adults), especially equids, which are represented by at least 11 individuals. The mammalian archaeofauna preserves numerous cut-marked and hammerstone-percussed bones. Made of primarily limestone and flint, the stone assemblage consists of core forms, débitage, and retouched pieces. Evidence of usewear traces is found on several of the flint artifacts, indicating meat processing by early hominins. Overall, our subsistence analysis indicates that early hominins were largely responsible for bone modification at the site, which is also corroborated by other relevant taphonomic evidence. Moreover, at 1.78 Ma, the cutmarked bones recovered from El-Kherba represent the earliest known evidence for ancestral hominin butchery activities and large animal foraging capabilities in northern Africa.

  9. The top of the Olduvai subchron in a high-resolution magnetostratigraphy from the West Turkana core WTK13, Hominin Sites and Paleolakes Drilling Project (HSPDP)

    NASA Astrophysics Data System (ADS)

    Sier, Mark; Langereis, Cor; Dupont-Nivet, Guillaume; Feibel, Craig; Jordeens, Jose; van der Lubbe, Jeroen; Beck, Catherine; Olago, Daniel; Cohen, Andrew

    2017-04-01

    One of the major challenges in understanding the evolution of our own species is identifying the role climate change has played in the evolution of earlier hominin species. To clarify the influence of climate, we need long and continuous high-resolution paleoclimate records, preferably obtained from hominin-bearing sediments, that are well-dated by tephro- and magnetostratigraphy and other methods. This is hindered, however, by the fact that fossil-bearing sediments are often discontinuous, and subject to weathering, which may lead to oxidation and remagnetization. To obtain fresh, unweathered sediments, the Hominin Sites and Paleolakes Drilling Project (HSPDP) collected a 216- meter core (WTK13) in 2013 from deposits of Early Pleistocene paleolake Lorenyang in the western Turkana Basin (Kenya). Here, we present the magnetostratigraphy of the core. Rock magnetic analyses reveal the presence of iron sulphides carrying the remanent magnetizations. To recover polarity orientation from the near-equatorial WTK13 core drilled at 5°N, we developed and successfully applied two independent drill-core reorientation methods taking advantage of (1) the sedimentary fabric as expressed in the Anisotropy of Magnetic Susceptibility (AMS) and (2) the occurrence of a viscous component oriented in the present day field. The reoriented directions reveal a normal to reversed polarity reversal identified as the top of the Olduvai subchron. From this excellent record, we find no evidence for the 'Vrica subchron' previously reported in the area. We suggest that outcrop-based interpretations supporting the presence of the Vrica subchron have been affected by the oxidation of iron sulphides initially present in the sediments as evident in the core record, and by subsequent remagnetization. Based on our new high-resolution magnetostratigraphy and stratigraphic markers, we provide constraints for an initial age model of the WTK13 core. We discuss the implications of the observed geomagnetic

  10. The hominins: a very conservative tribe? Last common ancestors, plasticity and ecomorphology in Hominidae. Or, What's in a name?

    PubMed

    Crompton, Robin Huw

    2016-04-01

    In the early 20th century the dominant paradigm for the ecological context of the origins of human bipedalism was arboreal suspension. In the 1960s, however, with recognition of the close genetic relationship of humans, chimpanzees and bonobos, and with the first field studies of mountain gorillas and common chimpanzees, it was assumed that locomotion similar to that of common chimpanzees and mountain gorillas, which appeared to be dominated by terrestrial knuckle-walking, must have given rise to human bipedality. This paradigm has been popular, if not universally dominant, until very recently. However, evidence that neither the knuckle-walking or vertical climbing of these apes is mechanically similar to human bipedalism, as well as the hand-assisted bipedality and orthograde clambering of orang-utans, has cast doubt on this paradigm. It now appears that the dominance of terrestrial knuckle-walking in mountain gorillas is an artefact seen only in the extremes of their range, and that both mountain and lowland gorillas have a generalized orthogrady similar to that seen in orang-utans. These data, together with evidence for continued arboreal competence in humans, mesh well with an increasing weight of fossil evidence suggesting that a mix of orang-utan and gorilla-like arboreal locomotion and upright terrestrial bipedalism characterized most australopiths. The late split date of the panins, corresponding to dates for separation of Homo and Australopithecus, leads to the speculation that competition with chimpanzees, as appears to exist today with gorillas, may have driven ecological changes in hominins and perhaps cladogenesis. However, selection for ecological plasticity and morphological conservatism is a core characteristic of Hominidae as a whole, including Hominini. © 2015 Anatomical Society.

  11. The Hominin Sites and Paleolakes Drilling Project (HSPDP): Understanding the paleoenvironmental and paleoclimatic context of human origins through continental drilling

    NASA Astrophysics Data System (ADS)

    Cohen, Andrew S.; Campisano, Christopher; Asrat, Asfawossen; Arrowsmith, Ramon; Deino, Alan; Feibel, Craig; Hill, Andrew; Kingston, John; Lamb, Henry; Lowenstein, Tim; Olago, Daniel; Bernhart Owen, R.; Renaut, Robin; Schabitz, Frank; Trauth, Martin

    2015-04-01

    The influence of climate and environmental history on human evolution is an existential question that continues to be hotly debated, in part because of the paucity of high resolution records collected in close proximity to the key fossil and archaeological evidence. To address this issue and transform the scientific debate, the HSPDP was developed to collect lacustrine sediment drill cores from basins in Kenya and Ethiopia that collectively encompass critical time intervals and locations for Plio-Quaternary human evolution in East Africa. After a 17 month campaign, drilling was completed in November, 2014, with over 1750m of core collected from 11 boreholes from five areas (1930m total drilling length, avg. 91% recovery). The sites, from oldest to youngest, include 1) N. Awash, Ethiopia (~3.5-2.9Ma core interval); 2) Baringo-Tugen Hills, Kenya (~3.3-2.5Ma); 3) West Turkana, Kenya (~1.9-1.4Ma); L. Magadi, Kenya (0.8-0Ma) and the Chew Bahir Basin, Ethiopia (~0.5-0Ma). Initial core description (ICD) and sampling for geochronology, geochemistry and paleoecology studies had been completed by mid2014, with the two remaining sites (Magadi and Chew Bahir) scheduled for ICD work in early 2015. Whereas the primary scientific targets were the lacustrine deposits from the hominin-bearing basin depocenters, many intervals of paleosols (representative of low lake stands and probable arid periods) were also encountered in drill cores. Preliminary analyses of drill core sedimentology and geochemistry show both long-term lake level changes and cyclic variability in lake levels, both of which may be indicative of climatic forcing events of interest to paleoanthropologists. Authors of this abstract also include the entire HSPDP field team.

  12. Conarticular congruence of the hominoid subtalar joint complex with implications for joint function in Plio-Pleistocene hominins.

    PubMed

    Prang, Thomas C

    2016-07-01

    The purpose of this study is to test the hypothesis that conarticular surfaces areas and curvatures are correlates of mobility at the hominoid talocalcaneal and talonavicular joints. Articular surface areas and curvatures of the talonavicular, anterior talocalcaneal, and posterior talocalcaneal joints were quantified using a total of 425 three-dimensional surface models of extant hominoid and fossil hominin tali, calcanei, and naviculars. Quadric surface fitting was used to calculate curvatures, pairwise comparisons were used to evaluate statistical differences between taxa, and regression was used to test for the effects of allometry. Pairwise comparisons show that the distributions of values for joint curvature indices follow the predicted arboreal-terrestrial morphocline in hominoid primates with no effect of body mass (PGLS p > 0.05). OH 8 (Homo habilis) and LB 1 (Homo floresiensis) can be accommodated within the range of human variation for the talonavicular joint, whereas MH2 (Australopithecus sediba) falls within the ranges of variation for Pan troglodytes and Gorilla gorilla in measures of posterior talocalcaneal joint congruity. Joint curvature indices are better discriminators than joint surface area indices, which may reflect a greater contribution of rotation, rather than translation, to joint movement in plantigrade taxa due to discrepancies in conarticular congruence and the "convex-concave" rule. The pattern of joint congruence in Au. sediba contributes to other data on the foot and ankle suggesting that the lateral side of the foot was more mobile than the medial side, which is consistent with suggestions of increased medial weight transfer associated with hyperpronation. Am J Phys Anthropol 160:446-457, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  13. The age of the hominin fossils from Jebel Irhoud, Morocco, and the origins of the Middle Stone Age.

    PubMed

    Richter, Daniel; Grün, Rainer; Joannes-Boyau, Renaud; Steele, Teresa E; Amani, Fethi; Rué, Mathieu; Fernandes, Paul; Raynal, Jean-Paul; Geraads, Denis; Ben-Ncer, Abdelouahed; Hublin, Jean-Jacques; McPherron, Shannon P

    2017-06-07

    The timing and location of the emergence of our species and of associated behavioural changes are crucial for our understanding of human evolution. The earliest fossil attributed to a modern form of Homo sapiens comes from eastern Africa and is approximately 195 thousand years old, therefore the emergence of modern human biology is commonly placed at around 200 thousand years ago. The earliest Middle Stone Age assemblages come from eastern and southern Africa but date much earlier. Here we report the ages, determined by thermoluminescence dating, of fire-heated flint artefacts obtained from new excavations at the Middle Stone Age site of Jebel Irhoud, Morocco, which are directly associated with newly discovered remains of H. sapiens. A weighted average age places these Middle Stone Age artefacts and fossils at 315 ± 34 thousand years ago. Support is obtained through the recalculated uranium series with electron spin resonance date of 286 ± 32 thousand years ago for a tooth from the Irhoud 3 hominin mandible. These ages are also consistent with the faunal and microfaunal assemblages and almost double the previous age estimates for the lower part of the deposits. The north African site of Jebel Irhoud contains one of the earliest directly dated Middle Stone Age assemblages, and its associated human remains are the oldest reported for H. sapiens. The emergence of our species and of the Middle Stone Age appear to be close in time, and these data suggest a larger scale, potentially pan-African, origin for both.

  14. Shared Human-Chimpanzee Pattern of Perinatal Femoral Shaft Morphology and Its Implications for the Evolution of Hominin Locomotor Adaptations

    PubMed Central

    Morimoto, Naoki; Zollikofer, Christoph P. E.; Ponce de León, Marcia S.

    2012-01-01

    Background Acquisition of bipedality is a hallmark of human evolution. How bipedality evolved from great ape-like locomotor behaviors, however, is still highly debated. This is mainly because it is difficult to infer locomotor function, and even more so locomotor kinematics, from fossil hominin long bones. Structure-function relationships are complex, as long bone morphology reflects phyletic history, developmental programs, and loading history during an individual’s lifetime. Here we discriminate between these factors by investigating the morphology of long bones in fetal and neonate great apes and humans, before the onset of locomotion. Methodology/Principal Findings Comparative morphometric analysis of the femoral diaphysis indicates that its morphology reflects phyletic relationships between hominoid taxa to a greater extent than taxon-specific locomotor adaptations. Diaphyseal morphology in humans and chimpanzees exhibits several shared-derived features, despite substantial differences in locomotor adaptations. Orangutan and gorilla morphologies are largely similar, and likely represent the primitive hominoid state. Conclusions/Significance These findings are compatible with two possible evolutionary scenarios. Diaphyseal morphology may reflect retained adaptive traits of ancestral taxa, hence human-chimpanzee shared-derived features may be indicative of the locomotor behavior of our last common ancestor. Alternatively, diaphyseal morphology might reflect evolution by genetic drift (neutral evolution) rather than selection, and might thus be more informative about phyletic relationships between taxa than about locomotor adaptations. Both scenarios are consistent with the hypothesis that knuckle-walking in chimpanzees and gorillas resulted from convergent evolution, and that the evolution of human bipedality is unrelated to extant great ape locomotor specializations. PMID:22848680

  15. Preserved microstructure and mineral distribution in tooth and periodontal tissues in early fossil hominin material from Koobi Fora, Kenya.

    PubMed

    Klinge, R Furseth; Dean, M C; Risnes, S; Erambert, M; Gunnaes, A E

    2009-01-01

    The aim of this study was to explore further the preservation of tissues and the mineral distribution in 1.6 million-year-old fossil hominin material from Koobi Fora, Kenya attributed to Paranthropus boisei (KNM-ER 1817). Bone, dentine and cementum microstructure were well preserved. Electron microprobe analysis of dentine and bone revealed an F-bearing apatite. Calcite now filled the original soft tissue spaces. The average Ca/P atomic ratio was 1.93, as compared to 1.67 in biological hydroxyapatite, indicating that the Ca-content had increased during fossilization. Analytical sums for mineral content were approximately 90 wt%. Some of the remaining 10 wt% may be preserved organic material. Demineralized dentine fragments showed irregularly distributed tubules encircled with a fibrous-like electron-dense material. A similar material was observed in demineralized dentine. Within this, structures resembling bacteria were seen. In demineralized bone an electron-dense material with a fibrous appearance and a banding pattern that repeated every 64 nm, similar to that of collagen, was noted. SEM of an enamel fragment (KNM-ER 6081) showed signs of demineralization/remineralization. Retzius lines, Hunter-Schreger bands and prism cross-striations spaced 3.7-7.1.microm apart were noted. Prisms were arranged in a pattern 3 configuration and deeper areas containing aprismatic enamel were occasionally observed. We conclude that a great deal of informative microstructure and ultrastructure remains preserved in this fossil material. We also hypothesize that the high mineral content of the tissues may 'protect' parts of the organic matrix from degradation, since our findings indicate that some organic matrix may still be present.

  16. Exploring the Potential of Laser Ablation Carbon Isotope Analysis for Examining Ecology during the Ontogeny of Middle Pleistocene Hominins from Sima de los Huesos (Northern Spain).

    PubMed

    Garcia, Nuria; Feranec, Robert S; Passey, Benjamin H; Cerling, Thure E; Arsuaga, Juan Luis

    2015-01-01

    Laser ablation of tooth enamel was used to analyze stable carbon isotope compositions of teeth of hominins, red deer, and bears from middle Pleistocene sites in the Sierra de Atapuerca in northern Spain, to investigate the possibility that this technique could be used as an additional tool to identify periods of physiological change that are not detectable as changes in tooth morphology. Most of the specimens were found to have minimal intra-tooth variation in carbon isotopes (< 2.3‰), suggesting isotopically uniform diets through time and revealing no obvious periods of physiological change. However, one of the two sampled hominin teeth displayed a temporal carbon isotope shift (3.2‰) that was significantly greater than observed for co-occurring specimens. The δ13C value of this individual averaged about -16‰ early in life, and -13‰ later in life. This isotopic change occurred on the canine crown about 4.2 mm from the root, which corresponds to an approximate age of two to four years old in modern humans. Our dataset is perforce small owing to the precious nature of hominid teeth, but it demonstrates the potential utility of the intra-tooth isotope profile method for extracting ontogenetic histories of human ancestors.

  17. Man the Fat Hunter: The Demise of Homo erectus and the Emergence of a New Hominin Lineage in the Middle Pleistocene (ca. 400 kyr) Levant

    PubMed Central

    Ben-Dor, Miki; Gopher, Avi; Hershkovitz, Israel; Barkai, Ran

    2011-01-01

    The worldwide association of H. erectus with elephants is well documented and so is the preference of humans for fat as a source of energy. We show that rather than a matter of preference, H. erectus in the Levant was dependent on both elephants and fat for his survival. The disappearance of elephants from the Levant some 400 kyr ago coincides with the appearance of a new and innovative local cultural complex – the Levantine Acheulo-Yabrudian and, as is evident from teeth recently found in the Acheulo-Yabrudian 400-200 kyr site of Qesem Cave, the replacement of H. erectus by a new hominin. We employ a bio-energetic model to present a hypothesis that the disappearance of the elephants, which created a need to hunt an increased number of smaller and faster animals while maintaining an adequate fat content in the diet, was the evolutionary drive behind the emergence of the lighter, more agile, and cognitively capable hominins. Qesem Cave thus provides a rare opportunity to study the mechanisms that underlie the emergence of our post-erectus ancestors, the fat hunters. PMID:22174868

  18. The Nature of Culture: an eight-grade model for the evolution and expansion of cultural capacities in hominins and other animals.

    PubMed

    Haidle, Miriam Noël; Bolus, Michael; Collard, Mark; Conard, Nicholas; Garofoli, Duilio; Lombard, Marlize; Nowell, April; Tennie, Claudio; Whiten, Andrew

    2015-07-20

    Tracing the evolution of human culture through time is arguably one of the most controversial and complex scholarly endeavors, and a broad evolutionary analysis of how symbolic, linguistic, and cultural capacities emerged and developed in our species is lacking. Here we present a model that, in broad terms, aims to explain the evolution and portray the expansion of human cultural capacities (the EECC model), that can be used as a point of departure for further multidisciplinary discussion and more detailed investigation. The EECC model is designed to be flexible, and can be refined to accommodate future archaeological, paleoanthropological, genetic or evolutionary psychology/behavioral analyses and discoveries. Our proposed concept of cultural behavior differentiates between empirically traceable behavioral performances and behavioral capacities that are theoretical constructs. Based largely on archaeological data (the 'black box' that most directly opens up hominin cultural evolution), and on the extension of observable problem-solution distances, we identify eight grades of cultural capacity. Each of these grades is considered within evolutionary-biological and historical-social trajectories. Importantly, the model does not imply an inevitable progression, but focuses on expansion of cultural capacities based on the integration of earlier achievements. We conclude that there is not a single cultural capacity or a single set of abilities that enabled human culture; rather, several grades of cultural capacity in animals and hominins expanded during our evolution to shape who we are today.

  19. Pleistocene Hominins as a Resource for Carnivores: A c. 500,000-Year-Old Human Femur Bearing Tooth-Marks in North Africa (Thomas Quarry I, Morocco)

    PubMed Central

    Daujeard, Camille; Geraads, Denis; Gallotti, Rosalia; Lefèvre, David; Mohib, Abderrahim; Raynal, Jean-Paul; Hublin, Jean-Jacques

    2016-01-01

    In many Middle Pleistocene sites, the co-occurrence of hominins with carnivores, who both contributed to faunal accumulations, suggests competition for resources as well as for living spaces. Despite this, there is very little evidence of direct interaction between them to-date. Recently, a human femoral diaphysis has been recognized in South-West of Casablanca (Morocco), in the locality called Thomas Quarry I. This site is famous for its Middle Pleistocene fossil hominins considered representatives of Homo rhodesiensis. The bone was discovered in Unit 4 of the Grotte à Hominidés (GH), dated to c. 500 ky and was associated with Acheulean artefacts and a rich mammalian fauna. Anatomically, it fits well within the group of known early Middle Pleistocene Homo, but its chief point of interest is that the diaphyseal ends display numerous tooth marks showing that it had been consumed shortly after death by a large carnivore, probably a hyena. This bone represents the first evidence of consumption of human remains by carnivores in the cave. Whether predated or scavenged, this chewed femur indicates that humans were a resource for carnivores, underlining their close relationships during the Middle Pleistocene in Atlantic Morocco. PMID:27120202

  20. Exploring the Potential of Laser Ablation Carbon Isotope Analysis for Examining Ecology during the Ontogeny of Middle Pleistocene Hominins from Sima de los Huesos (Northern Spain)

    PubMed Central

    Garcia, Nuria; Feranec, Robert S.; Passey, Benjamin H.; Cerling, Thure E.; Arsuaga, Juan Luis

    2015-01-01

    Laser ablation of tooth enamel was used to analyze stable carbon isotope compositions of teeth of hominins, red deer, and bears from middle Pleistocene sites in the Sierra de Atapuerca in northern Spain, to investigate the possibility that this technique could be used as an additional tool to identify periods of physiological change that are not detectable as changes in tooth morphology. Most of the specimens were found to have minimal intra-tooth variation in carbon isotopes (< 2.3‰), suggesting isotopically uniform diets through time and revealing no obvious periods of physiological change. However, one of the two sampled hominin teeth displayed a temporal carbon isotope shift (3.2‰) that was significantly greater than observed for co-occurring specimens. The δ13C value of this individual averaged about -16‰ early in life, and -13‰ later in life. This isotopic change occurred on the canine crown about 4.2 mm from the root, which corresponds to an approximate age of two to four years old in modern humans. Our dataset is perforce small owing to the precious nature of hominid teeth, but it demonstrates the potential utility of the intra-tooth isotope profile method for extracting ontogenetic histories of human ancestors. PMID:26673156

  1. Pleistocene Hominins as a Resource for Carnivores: A c. 500,000-Year-Old Human Femur Bearing Tooth-Marks in North Africa (Thomas Quarry I, Morocco).

    PubMed

    Daujeard, Camille; Geraads, Denis; Gallotti, Rosalia; Lefèvre, David; Mohib, Abderrahim; Raynal, Jean-Paul; Hublin, Jean-Jacques

    2016-01-01

    In many Middle Pleistocene sites, the co-occurrence of hominins with carnivores, who both contributed to faunal accumulations, suggests competition for resources as well as for living spaces. Despite this, there is very little evidence of direct interaction between them to-date. Recently, a human femoral diaphysis has been recognized in South-West of Casablanca (Morocco), in the locality called Thomas Quarry I. This site is famous for its Middle Pleistocene fossil hominins considered representatives of Homo rhodesiensis. The bone was discovered in Unit 4 of the Grotte à Hominidés (GH), dated to c. 500 ky and was associated with Acheulean artefacts and a rich mammalian fauna. Anatomically, it fits well within the group of known early Middle Pleistocene Homo, but its chief point of interest is that the diaphyseal ends display numerous tooth marks showing that it had been consumed shortly after death by a large carnivore, probably a hyena. This bone represents the first evidence of consumption of human remains by carnivores in the cave. Whether predated or scavenged, this chewed femur indicates that humans were a resource for carnivores, underlining their close relationships during the Middle Pleistocene in Atlantic Morocco.

  2. Taphonomic Analysis of the Faunal Assemblage Associated with the Hominins (Australopithecus sediba) from the Early Pleistocene Cave Deposits of Malapa, South Africa

    PubMed Central

    Val, Aurore; Dirks, Paul H. G. M.; Backwell, Lucinda R.; d’Errico, Francesco; Berger, Lee R.

    2015-01-01

    Here we present the results of a taphonomic study of the faunal assemblage associated with the hominin fossils (Australopithecus sediba) from the Malapa site. Results include estimation of body part representation, mortality profiles, type of fragmentation, identification of breakage patterns, and microscopic analysis of bone surfaces. The diversity of the faunal spectrum, presence of animals with climbing proclivities, abundance of complete and/or articulated specimens, occurrence of antimeric sets of elements, and lack of carnivore-modified bones, indicate that animals accumulated via a natural death trap leading to an area of the cave system with no access to mammalian scavengers. The co-occurrence of well preserved fossils, carnivore coprolites, deciduous teeth of brown hyaena, and some highly fragmented and poorly preserved remains supports the hypothesis of a mixing of sediments coming from distinct chambers, which collected at the bottom of the cave system through the action of periodic water flow. This combination of taphonomic features explains the remarkable state of preservation of the hominin fossils as well as some of the associated faunal material. PMID:26061082

  3. Taphonomic Analysis of the Faunal Assemblage Associated with the Hominins (Australopithecus sediba) from the Early Pleistocene Cave Deposits of Malapa, South Africa.

    PubMed

    Val, Aurore; Dirks, Paul H G M; Backwell, Lucinda R; d'Errico, Francesco; Berger, Lee R

    2015-01-01

    Here we present the results of a taphonomic study of the faunal assemblage associated with the hominin fossils (Australopithecus sediba) from the Malapa site. Results include estimation of body part representation, mortality profiles, type of fragmentation, identification of breakage patterns, and microscopic analysis of bone surfaces. The diversity of the faunal spectrum, presence of animals with climbing proclivities, abundance of complete and/or articulated specimens, occurrence of antimeric sets of elements, and lack of carnivore-modified bones, indicate that animals accumulated via a natural death trap leading to an area of the cave system with no access to mammalian scavengers. The co-occurrence of well preserved fossils, carnivore coprolites, deciduous teeth of brown hyaena, and some highly fragmented and poorly preserved remains supports the hypothesis of a mixing of sediments coming from distinct chambers, which collected at the bottom of the cave system through the action of periodic water flow. This combination of taphonomic features explains the remarkable state of preservation of the hominin fossils as well as some of the associated faunal material.

  4. Lithic landscapes: early human impact from stone tool production on the central Saharan environment.

    PubMed

    Foley, Robert A; Lahr, Marta Mirazón

    2015-01-01

    Humans have had a major impact on the environment. This has been particularly intense in the last millennium but has been noticeable since the development of food production and the associated higher population densities in the last 10,000 years. The use of fire and over-exploitation of large mammals has also been recognized as having an effect on the world's ecology, going back perhaps 100,000 years or more. Here we report on an earlier anthropogenic environmental change. The use of stone tools, which dates back over 2.5 million years, and the subsequent evolution of a technologically-dependent lineage required the exploitation of very large quantities of rock. However, measures of the impact of hominin stone exploitation are rare and inherently difficult. The Messak Settafet, a sandstone massif in the Central Sahara (Libya), is littered with Pleistocene stone tools on an unprecedented scale and is, in effect, a man-made landscape. Surveys showed that parts of the Messak Settafet have as much as 75 lithics per square metre and that this fractured debris is a dominant element of the environment. The type of stone tools--Acheulean and Middle Stone Age--indicates that extensive stone tool manufacture occurred over the last half million years or more. The lithic-strewn pavement created by this ancient stone tool manufacture possibly represents the earliest human environmental impact at a landscape scale and is an example of anthropogenic change. The nature of the lithics and inferred age may suggest that hominins other than modern humans were capable of unintentionally modifying their environment. The scale of debris also indicates the significance of stone as a critical resource for hominins and so provides insights into a novel evolutionary ecology.

  5. Lithic Landscapes: Early Human Impact from Stone Tool Production on the Central Saharan Environment

    PubMed Central

    Foley, Robert A.; Lahr, Marta Mirazón

    2015-01-01

    Humans have had a major impact on the environment. This has been particularly intense in the last millennium but has been noticeable since the development of food production and the associated higher population densities in the last 10,000 years. The use of fire and over-exploitation of large mammals has also been recognized as having an effect on the world’s ecology, going back perhaps 100,000 years or more. Here we report on an earlier anthropogenic environmental change. The use of stone tools, which dates back over 2.5 million years, and the subsequent evolution of a technologically-dependent lineage required the exploitation of very large quantities of rock. However, measures of the impact of hominin stone exploitation are rare and inherently difficult. The Messak Settafet, a sandstone massif in the Central Sahara (Libya), is littered with Pleistocene stone tools on an unprecedented scale and is, in effect, a man-made landscape. Surveys showed that parts of the Messak Settafet have as much as 75 lithics per square metre and that this fractured debris is a dominant element of the environment. The type of stone tools—Acheulean and Middle Stone Age—indicates that extensive stone tool manufacture occurred over the last half million years or more. The lithic-strewn pavement created by this ancient stone tool manufacture possibly represents the earliest human environmental impact at a landscape scale and is an example of anthropogenic change. The nature of the lithics and inferred age may suggest that hominins other than modern humans were capable of unintentionally modifying their environment. The scale of debris also indicates the significance of stone as a critical resource for hominins and so provides insights into a novel evolutionary ecology. PMID:25760999

  6. Comparative morphology of the hominin and African ape hyoid bone, a possible marker of the evolution of speech.

    PubMed

    Steele, James; Clegg, Margaret; Martelli, Sandra

    2013-10-01

    This study examines the morphology of the hyoid in three closely related species, Homo sapiens, Pan troglodytes, and Gorilla gorilla. Differences and similarities between the hyoids of these species are characterized and used to interpret the morphology and affi nities of the Dikika A. afarensis, Kebara 2 Neanderthal, and other fossil hominin hyoid bones. Humans and African apes are found to have distinct hyoid morphologies. In humans the maximum width across the distal tips of the articulated greater horns is usually slightly greater than the maximum length (distal greater horn tip to most anterior point of the hyoid body in the midline). A different pattern is usually found in the African ape hyoids, which have much greater maximum lengths. In humans, the hyoid body is also much more anteroposteriorly shallow in proportion to its height and width, and this is true for all age classes. The Dikika australopithecine hyoid body proportions are chimpanzeelike. A discriminant function analysis, using a larger subadult sample from the three extant species than that reported by Alemseged et al. (2006), confirms this finding. The Kebara hyoid dimensions (body alone, and articulated body and greater horns) are almost all within the observed range for human hyoids. Discriminant functions clearly distinguish human from African ape hyoids and classify the Kebara 2 hyoid as human (confirming the finding of Arensburg et al. 1989). Our virtual dissection of a chimpanzee air sac system shows its subhyoid extension into the dorsal hyoid body. Following Alemseged et al. (2006), the expanded bulla characteristic of the African ape and australopithecine hyoid body is therefore interpreted as refl ecting the presence of such a laryngeal air sac extension. Its absence in the human, Neanderthal, and H. heidelbergensis (Atapuerca SH) hyoids implicates the loss of the laryngeal air sacs as a derived Neanderthal and modern human trait, which evolved no later than the middle Pleistocene. If

  7. Re-appraisal of the stratigraphy and determination of new U-Pb dates for the Sterkfontein hominin site, South Africa.

    PubMed

    Pickering, Robyn; Kramers, Jan D

    2010-07-01

    Sterkfontein Caves is the single richest early hominin site in the world with deposits yielding one or more species of Australopithecus and possible early Homo, as well as an extensive faunal collection. The inability to date the southern African cave sites accurately or precisely has hindered attempts to integrate the hominin fossil evidence into pan-African scenarios about human evolutionary history, and especially hominin biogeography. We have used U-Pb and U-Th techniques to date sheets of calcium carbonate flowstone inter-bedded between the fossiliferous sediments. For the first time, absolute age ranges can be assigned to the fossil-bearing deposits: Member 2 is between 2.8 +/- 0.28 and 2.6 +/- 0.30 Ma and Member 4 between 2.65 +/- 0.30 and 2.01 +/- 0.05 Ma. The age of 2.01 +/- 0.05 Ma for the top of Member 4 constrains the last appearance of Australopithecus africanus to 2 Ma. In the Silberberg Grotto we have reproduced the U-Pb age of approximately 2.2 Ma of for the flowstones associated with StW573. We believe that these deposits, including the fossil and the flowstones, accumulated rapidly around 2.2 Ma. The stratigraphy of the site is complex as sediments are exposed both in the underground chambers and at surface. We present a new interpretation of the stratigraphy based on surface mapping, boreholes logs and U-Pb ages. Every effort was made to retain the Member system, however, only Members 2 and 4 are recognized in the boreholes. We propose that the deposits formally known as Member 3 are in fact the distal equivalents of Member 4. The sediments of Members 2 and 4 consisted of cone-like deposits and probably never filled up the cave. The U-Th ages show that there are substantial deposits younger than 400 ka in the underground cave, underlying the older deposits, highlighting again that these cave fills are not simple layer-cakes.

  8. Discriminating Between Tectonic and Climatic Controls on Early Hominin Paleoenvironments From the Koobi Fora Region, Northeastern Turkana Basin, Kenya: Part II

    NASA Astrophysics Data System (ADS)

    Quinn, R. L.; Lepre, C. J.

    2004-12-01

    Global climate is often elected as a catalyst for environmental change and used to characterize selective pressures acting on Plio-Pleistocene African hominins. Vrba's Habitat Theory (1992) and Pott's Variability Selection (1998) credit mammalian evolutionary pattern and process to global climate regulated by orbital forcing. Feibel (1999: 276) argues the need for a middle ground, tethering the "global-scale climatic phenomena" to "environmental change, habitat shift, and biotic evolution" and offers the basin as a scale for analysis. Feibel suggests that all basins are not created equal, and will respond to climate change with different sensitivities and thresholds. As such, interpretations of climate proxies must account for differences in basin size, climatic regime(s), topography, geology, and water availability when drawing relationships to global phenomena. Here we examine pedogenic carbonate isotopes (d13C, d18O) from the Plio-Pleistocene Koobi Fora Region to elucidate the differential influences of climate, tectonics, and deposition on ecological factors of early hominin evolution in the northeastern Turkana Basin of Kenya. One of the richest Plio-Pleistocene fossil localities in Africa, Koobi Fora has served as a setting for hominin evolution between 4.0 and 1.0 Ma. Numerous paleosols, stratigraphically controlled by tuffaceous marker beds, are preserved in the Plio-Pleistocene sediments of the Koobi Fora Formation. Cerling and others (1988) and Wynn (2000) conducted isotopic studies of pedogenic carbonates from the Plio-Pleistocene Omo Group deposits of the Turkana Basin. With these data Wynn (2004) demonstrates stepwise d13C shifts over the last 4.0 Ma, with marked events at 2.5 and 1.8 Ma, and interprets increased aridity on a basin scale due to comparable records on the east and west side of present Lake Turkana. In this study, we increased the sample size of the current database and conducted widespread sampling of synchronous lateral horizons in the

  9. Climate and environment of the earliest West European hominins inferred from amphibian and squamate reptile assemblages: Sima del Elefante Lower Red Unit, Atapuerca, Spain

    NASA Astrophysics Data System (ADS)

    Blain, Hugues-Alexandre; Bailon, Salvador; Cuenca-Bescós, Gloria; Bennàsar, Maria; Rofes, Juan; López-García, Juan Manuel; Huguet, Rosa; Arsuaga, Juan Luis; Bermúdez de Castro, José Maria; Carbonell, Eudald

    2010-11-01

    The Sima del Elefante cave, in the Sierra de Atapuerca (Burgos, Spain), is famous for the fact that level TE9 of its Lower Red Unit recently delivered the oldest hominin remains of Western Europe, identified as Homo antecessor and dated by biostratigraphy and radiometric methods to ca 1.2 Ma. Given the importance of this discovery, every effort is being made to reconstruct the landscapes where these hominins once thrived. The amphibian and squamate reptile assemblage of the Sima del Elefante Lower Red Unit is here studied for the first time. The faunal list comprises at least 17 species (roughly 12,000 bone fossil remains): Salamandra salamandra, Triturus cf. marmoratus, Alytes obstetricans, Pelobates cultripes, Pelodytes punctatus, Bufo bufo, Bufo calamita, Hyla arborea, Rana sp., cf. Pelophylax sp., Lacerta s.l., small-sized indeterminate lacertids, Anguis fragilis, Natrix cf. natrix, Natrix cf. maura, Coronella cf. girondica and Vipera sp. As the amphibians and squamate reptiles do not differ at species level from the extant herpetofauna of the Iberian Peninsula, they can contribute to the reconstruction of the landscape and climate. In this paper, the mutual climatic range and habitat weighting methods are applied to the amphibian and squamate reptile assemblages in order to estimate quantitative data. The results from the squamate and amphibian study indicate that during the hominin presence the mean annual temperature (MAT = 10-13 °C) was always slightly warmer than at present and the mean annual precipitation (MAP = 800-1000 mm) was greater than today in the Burgos area. The landscape had open habitats in the vicinity of the Atapuerca caves throughout the sequence, with wet points in the surrounding area, and a predominance of humid meadows and open woodlands. These results mainly agree with those for large mammals, small mammals and the pollen analysis. The climate and landscape of TE-LRU are very similar to those reconstructed for the TD6 "Aurora Stratum

  10. Another window to the subsistence of Middle Pleistocene hominins in Europe: A taphonomic study of Cuesta de la Bajada (Teruel, Spain)

    NASA Astrophysics Data System (ADS)

    Domínguez-Rodrigo, Manuel; Barba, Rebeca; Soto, Enrique; Sesé, Carmen; Santonja, Manuel; Pérez-González, Alfredo; Yravedra, José; Galán, Ana Belén

    2015-10-01

    Cuesta de la Bajada is a Middle Pleistocene site (MIS 8-9) in which some of the earliest evidence of Middle Paleolithic stone tool tradition is documented. The small format tool assemblage, dominated by simple flakes and scrapers, is associated to abundant remains of equids and cervids, in which both percussion and cut marks are well represented. The anatomical distribution of these bone surface modifications indicate primary access to fleshed carcasses by hominins. Hunting is further supported by the analysis of age profiles, in which prime adults are predominant both in equids and cervids. The taphonomic analysis of the site adds more information to human predatory behaviors as documented in other Middle Pleistocene sites and is one of the best examples of hunting documented in the Middle Pleistocene European archaeological record.

  11. Paleogeographic variations of pedogenic carbonate delta13C values from Koobi Fora, Kenya: implications for floral compositions of Plio-Pleistocene hominin environments.

    PubMed

    Quinn, Rhonda L; Lepre, Christopher J; Wright, James D; Feibel, Craig S

    2007-11-01

    Plio-Pleistocene East African grassland expansion and faunal macroevolution, including that of our own lineage, are attributed to global climate change. To further understand environmental factors of early hominin evolution, we reconstruct the paleogeographic distribution of vegetation (C(3)-C(4) pathways) by stable carbon isotope (delta(13)C) analysis of pedogenic carbonates from the Plio-Pleistocene Koobi Fora region, northeast Lake Turkana Basin, Kenya. We analyzed 202 nodules (530 measurements) from ten paleontological/archaeological collecting areas spanning environments over a 50-km(2) area. We compared results across subregions in evolving fluviolacustrine depositional environments in the Koobi Fora Formation from 2.0-1.5 Ma, a stratigraphic interval that temporally brackets grassland ascendancy in East Africa. Significant differences in delta(13)C values between subregions are explained by paleogeographic controls on floral composition and distribution. Our results indicate grassland expansion between 2.0 and 1.75 Ma, coincident with major shifts in basin-wide sedimentation and hydrology. Hypotheses may be correct in linking Plio-Pleistocene hominin evolution to environmental changes from global climate; however, based on our results, we interpret complexity from proximate forces that mitigated basin evolution. An approximately 2.5 Ma tectonic event in southern Ethiopia and northern Kenya exerted strong effects on paleography in the Turkana Basin from 2.0-1.5 Ma, contributing to the shift from a closed, lacustrine basin to one dominated by open, fluvial conditions. We propose basin transformation decreased residence time for Omo River water and expanded subaerial floodplain landscapes, ultimately leading to reduced proportions of wooded floras and the establishment of habitats suitable for grassland communities.

  12. When felids and hominins ruled at Olduvai Gorge: A machine learning analysis of the skeletal profiles of the non-anthropogenic Bed I sites

    NASA Astrophysics Data System (ADS)

    Arriaza, Mari Carmen; Domínguez-Rodrigo, Manuel

    2016-05-01

    In the past twenty years, skeletal part profiles, which are prone to equifinality, have not occupied a prominent role in the interpretation of early Pleistocene sites on Africa. Alternatively, taphonomic studies on bone surface modifications and bone breakage patterns, have provided heuristic interpretations of some of the best preserved archaeological record of this period; namely, the Olduvai Bed I sites. The most recent and comprehensive taphonomic study of these sites (Domínguez-Rodrigo et al., 2007a) showed that FLK Zinj was an anthropogenic assemblage in which hominins acquired carcasses via primary access. That study also showed that the other sites were palimpsests with minimal or no intervention by hominins. The FLK N, FLK NN and DK sequence seemed to be dominated by single-agent (mostly, felid) or multiple-agent (mostly, felid-hyenid) processes. The present study re-analyzes the Bed I sites focusing on skeletal part profiles. Machine learning methods, which incorporate complex algorithms, are powerful predictive and classification methods and have the potential to better extract information from skeletal part representation than past approaches. Here, multiple algorithms (via decision trees, neural networks, random forests and support vector machines) are combined to produce a solid interpretation of bone accumulation agency at the Olduvai Bed I sites. This new approach virtually coincides with previous taphonomic interpretations on a site by site basis and shows that felids were dominant accumulating agents over hyenas during Bed I times. The recent discovery of possibly a modern lion-accumulated assemblage at Olduvai Gorge (Arriaza et al., submitted) provides a very timely analog for this interpretation.

  13. Stratigraphy, U-Th chronology, and paleoenvironments at Gladysvale Cave: insights into the climatic control of South African hominin-bearing cave deposits.

    PubMed

    Pickering, Robyn; Hancox, Phillip J; Lee-Thorp, Julia A; Grün, Rainer; Mortimer, Graham E; McCulloch, Malcolm; Berger, Lee R

    2007-11-01

    Gladysvale Cave is one of the few Plio-Pleistocene hominin-bearing cave sites in South Africa that contains a well-stratified cave fill with clastic sediments interspersed with flowstones. The clastic sediments can be divided into units based on the presence of intercalated flowstones, forming flowstone bounded units (FBU). Ten MC-ICP-MS uranium-series dates on several flowstone horizons in the Gladysvale Internal Deposit fan indicate deposition from the late mid-Pleistocene ( approximately 570 ka) to Holocene ( approximately 7 ka) during limited periods of higher effective moisture. Clastic sedimentation occurred during the interceding, presumably more arid, periods. This sequence is not consistent with earlier models for South African caves that simply assumed interglacial sedimentation and glacial erosion. (13)C/(12)C data suggest that flowstone tended to form during periods with higher proportions of C(3) plants in the local vegetation, while clastic sediments reflect higher proportions of C(4) grasses, although this is not always the case. We argue that flowstones are precipitated during periods of higher effective precipitation and restricted cave entrances, while clastic sediments accumulated during periods with more open vegetation. The sedimentary fill of the fossiliferous deposits are, therefore, highly episodic in nature, with large periods of time unlikely to be represented. This has serious implications for the other hominin-bearing caves close by, as these deposits are likely to be similarly episodic. This is especially pertinent when addressing extinction events and reconstructions of paleoenvironments, as large periods of time may be unrecorded. The Gladysvale Cave fill sediments may serve as a climatically forced chronostratigraphic model for these less well-stratified and well-dated Plio-Pleistocene sites.

  14. Body Segment Differences in Surface Area, Skin Temperature and 3D Displacement and the Estimation of Heat Balance during Locomotion in Hominins

    PubMed Central

    Cross, Alan; Collard, Mark; Nelson, Andrew

    2008-01-01

    The conventional method of estimating heat balance during locomotion in humans and other hominins treats the body as an undifferentiated mass. This is problematic because the segments of the body differ with respect to several variables that can affect thermoregulation. Here, we report a study that investigated the impact on heat balance during locomotion of inter-segment differences in three of these variables: surface area, skin temperature and rate of movement. The approach adopted in the study was to generate heat balance estimates with the conventional method and then compare them with heat balance estimates generated with a method that takes into account inter-segment differences in surface area, skin temperature and rate of movement. We reasoned that, if the hypothesis that inter-segment differences in surface area, skin temperature and rate of movement affect heat balance during locomotion is correct, the estimates yielded by the two methods should be statistically significantly different. Anthropometric data were collected on seven adult male volunteers. The volunteers then walked on a treadmill at 1.2 m/s while 3D motion capture cameras recorded their movements. Next, the conventional and segmented methods were used to estimate the volunteers' heat balance while walking in four ambient temperatures. Lastly, the estimates produced with the two methods were compared with the paired t-test. The estimates of heat balance during locomotion yielded by the two methods are significantly different. Those yielded by the segmented method are significantly lower than those produced by the conventional method. Accordingly, the study supports the hypothesis that inter-segment differences in surface area, skin temperature and rate of movement impact heat balance during locomotion. This has important implications not only for current understanding of heat balance during locomotion in hominins but also for how future research on this topic should be approached. PMID

  15. Plio-Pleistocene facies environments from the KBS Member, Koobi Fora Formation: implications for climate controls on the development of lake-margin hominin habitats in the northeast Turkana Basin (northwest Kenya).

    PubMed

    Lepre, Christopher J; Quinn, Rhonda L; Joordens, Josephine C A; Swisher, Carl C; Feibel, Craig S

    2007-11-01

    Climate change is hypothesized as a cause of major events of Plio-Pleistocene East African hominin evolution, but the vertically discontinuous and laterally confined nature of the relevant geological records has led to difficulties with assessing probable links between the two. High-resolution sedimentary sequences from lacustrine settings can provide comprehensive data of environmental changes and detailed correlations with well-established orbital and marine records of climate. Hominin-bearing deposits from Koobi Fora Ridge localities in the northeast Turkana Basin of Kenya are an archive of Plio-Pleistocene lake-margin sedimentation though significant developmental junctures of northern African climates, East African environments, and hominin evolution. This study examines alluvial channel and floodplain, nearshore lacustrine, and offshore lacustrine facies environments for the approximately 136-m-thick KBS Member (Koobi Fora Formation) exposed at the Koobi Fora Ridge. Aspects of the facies environments record information on the changing hydrosedimentary dynamics of the lake margin and give insights into potential climatic controls. Seasonal/yearly climate changes are represented by the varve-like laminations in offshore mudstones and the slickensides, dish-shaped fractures, and other paleosol features overprinted on floodplain strata. Vertical shifts between facies environments, however, are interpreted to indicate lake-level fluctuations deriving from longer-term, dry-wet periods in monsoonal rainfall. Recurrence periods for the inferred lake-level changes range from about 10,000 to 50,000 years, and several are consistent with the average estimated timescales of orbital precession ( approximately 20,000 years) and obliquity ( approximately 40,000 years). KBS Member facies environments from the Koobi Fora Ridge document the development of lake-margin hominin habitats in the northeast Turkana Basin. Environmental changes in these habitats may be a result of

  16. Central line infections - hospitals

    MedlinePlus

    ... infection; CVC - infection; Central venous device - infection; Infection control - central line infection; Nosocomial infection - central line infection; Hospital acquired infection - central line infection; Patient safety - central ...

  17. Discriminating Between Tectonic and Climatic Controls on Early Hominin Paleoenvironments From the Koobi Fora Region, Northeastern Turkana Basin, Kenya: Part I

    NASA Astrophysics Data System (ADS)

    Lepre, C. J.; Quinn, R. L.

    2004-12-01

    Understanding controls on environmental records from Plio-Pleistocene Africa is critical for interpreting human origins. Recent geological studies from East Africa have focused on the relationship between Plio-Pleistocene patterns of hominin evolution, environmental change, and climate preserved in stratigraphic records of sedimentary basins (e.g. deMenocal, 2004; Wynn, 2004). Despite the fact that tectonics is a primary control on sedimentation in East African basins (e.g. Baker, 1986; Frostick, 1997), relatively few studies have either investigated its potential influence on early hominin evolution or attempted to discriminate between tectonic and climate controls on paleoenvironmental change. Presented is a study that explores these issues. Within the Koobi Fora Formation, between 4.0 and 2.5 Ma, environmental change is related to an overall trend of linear rates of tectonic subsidence. However, smaller-scale fluctuations in subsidence rates established lakes during times of increased subsidence followed by the transition to rivers during times of decreased subsidence and basin infilling (Feibel, 1994a, 2000). In contrast, environmental change during the period between 2.5 and 1.5 Ma was forced by changes in half-graben propagation, fault movement, and subsidence. This change is recorded within a stratigraphic sequence that is defined by major (erosional) boundary surface unconformities. The sequence is internally comprised of stable-lacustrine; stable-lacustrine, delta, and ephemeral-lacustrine; and fluvial environments of deposition. This environmental progression defines lowstand, transgressive, and highstand systems tracts respectively. Transition between systems tracts and depositional environments was controlled by rates of tectonic subsidence. The formation of stable-lacustrine environments of deposition during the lowstand systems tract was due to subsidence rates out-pacing sedimentation rates that was associated with a major tectonic event

  18. Macromammalian faunas, biochronology and palaeoecology of the early Pleistocene Main Quarry hominin-bearing deposits of the Drimolen Palaeocave System, South Africa

    PubMed Central

    Herries, Andy I.R.; Menter, Colin G.

    2016-01-01

    The Drimolen Palaeocave System Main Quarry deposits (DMQ) are some of the most prolific hominin and primate-bearing deposits in the Fossil Hominids of South Africa UNESCO World Heritage Site. Discovered in the 1990s, excavations into the DMQ have yielded a demographically diverse sample of Paranthropus robustus (including DNH 7, the most complete cranium of the species recovered to date), early Homo, Papio hamadryas robinsoni and Cercopithecoides williamsi. Alongside the hominin and primate sample is a diverse macromammalian assemblage, but prior publications have only provided a provisional species list and an analysis of the carnivores recovered prior to 2008. Here we present the first description and analysis of the non-primate macromammalian faunas from the DMQ, including all 826 taxonomically identifiable specimens catalogued from over two decades of excavation. We also provide a biochronological interpretation of the DMQ deposits and an initial discussion of local palaeoecology based on taxon representation.The current DMQ assemblage consists of the remains of minimally 147 individuals from 9 Orders and 14 Families of mammals. The carnivore assemblage described here is even more diverse than established in prior publications, including the identification of Megantereon whitei, Lycyaenops silberbergi, and first evidence for the occurrence of Dinofelis cf. barlowi and Dinofelis aff. piveteaui within a single South African site deposit. The cetartiodactyl assemblage is dominated by bovids, with the specimen composition unique in the high recovery of horn cores and dominance of Antidorcas recki remains. Other cetartiodactyl and perissodactyl taxa are represented by few specimens, as are Hystrix and Procavia; the latter somewhat surprisingly so given their common occurrence at penecontemporaneous deposits in the region. Equally unusual (particularly given the size of the sample) is the identification of single specimens of giraffoid, elephantid and aardvark

  19. Hominin Sites and Paleolakes Drilling Project: A 500,000-year climate record from Chew Bahir, a key site in southern Ethio