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Australopithecus sediba was uniquely related to Australopithecus africanus

Malapa Hominin (MH) 1, an immature individual whose second permanent molars had recently reached occlusion at the time of death, is the holotype of Australopithecus sediba, a 2-myr-old South African taxon that has been hypothesized to link phylogenetically australopith-grade hominins to the Homo clade. Given the existence of 2.8 myr-old fossils of Homo in eastern Africa, this hypothesis implies a ghost lineage spanning at least 800 kyr. An alternative hypothesis posits a unique relationship between Au. sediba and Australopithecus africanus, which predates the Malapa hominins in southern Africa and whose phylogenetic relationships remain ambiguous. The craniofacial morphology of MH 1 looms large in the framing of the two hypotheses. These alternatives were evaluated in two ways. First, it was investigated whether the craniofacial morphology of MH 1 was ontogenetically stable at death. Based on data from a late-growth series of chimpanzee, gorilla, and modern human crania, we found that key aspects of MH 1's resemblance to Homo can be accounted for by its immaturity. Second, MH 1 was studied with an eye to identifying craniofacial synapomorphies shared with Au. africanus. In this case, MH 1 shows unambiguous affinities in its zygomaticomaxillary and supraorbital morphology to crania from Sterkfontein Member 4, which we found to exhibit unusual derived morphology compared to Homo and other australopiths. It is argued that MH 1 provides clear evidence that A. sediba was uniquely related to Au. africanus and that the hypothesis of an extensive ghost lineage connecting Au. sediba to the root of the Homo clade is unwarranted.

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Hominin evolution in subequatorial Africa

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.

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Pressure flaking to serrate bifacial points for the hunt during the MIS5 at Sibudu Cave (South Africa)

Projectile technology is considered to appear early in the southern African Middle Stone Age (MSA) and the rich and high resolution MSA sequence of Sibudu Cave in KwaZulu-Natal has provided many new insights about the use and hafting of various projectile forms. The results of a functional and technological analysis are presented on a series of unpublished serrated bifacial points recently recovered from the basal deposits of Sibudu Cave. These serrated tools, which only find equivalents in the neighbouring site of Umhlatuzana, precede the Still Bay techno-complex and are older than 77 ka BP. Independent residue and use-wear analyses were performed in a phased procedure involving two separate analysts, which allowed the engagement between two separate lines of functional evidence. Thanks to the excellent preservation at Sibudu Cave, a wide range of animal, plant and mineral residues were observed in direct relation with diagnostic wear patterns. The combination of technological, wear and residue evidence allowed us to confirm that the serration was manufactured with bone compressors and that the serrated points were mounted with a composite adhesive as the tips of projectiles used in hunting activities. The suite of technological and functional data pushes back the evidence for the use of pressure flaking during the MSA and highlights the diversity of the technical innovations adopted by southern African MSA populations. It is suggested the serrated points from the stratigraphic units Adam to Darya of Sibudu illustrate one important technological adaptation of the southern African MSA and provide another example of the variability of MSA bifacial technologies.

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Neandertal and Denisovan DNA from Pleistocene sediments

Although a rich record of Pleistocene human-associated archaeological assemblages exists, the scarcity of hominin fossils often impedes the understanding of which hominins occupied a site. Using targeted enrichment of mitochondrial DNA we show that cave sediments represent a rich source of ancient mammalian DNA that often includes traces of hominin DNA, even at sites and in layers where no hominin remains have been discovered. By automation-assisted screening of numerous sediment samples we detect Neandertal DNA in eight archaeological layers from four caves in Eurasia. In Denisova Cave we retrieved Denisovan DNA in a Middle Pleistocene layer near the bottom of the stratigraphy. Our work opens the possibility to detect the presence of hominin groups at sites and in areas where no skeletal remains are found.

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A team of archaeologists claim archaeological evidence at the 130,000 year old Cerutti Mastodon site, California, USA

The earliest dispersal of humans into North America is a contentious subject, and proposed early sites are required to meet the following criteria for acceptance: (1) archaeological evidence is found in a clearly defined and undisturbed geologic context; (2) age is determined by reliable radiometric dating; (3) multiple lines of evidence from interdisciplinary studies provide consistent results; and (4) unquestionable artefacts are found in primary context1, 2. Here a team of scientists describe the Cerutti Mastodon (CM) site, an archaeological site from the early late Pleistocene epoch, where in situ hammerstones and stone anvils occur in spatio-temporal association with fragmentary remains of a single mastodon (Mammut americanum). The CM site contains spiral-fractured bone and molar fragments, indicating that breakage occured while fresh. Several of these fragments also preserve evidence of percussion. The occurrence and distribution of bone, molar and stone refits suggest that breakage occurred at the site of burial. Five large cobbles (hammerstones and anvils) in the CM bone bed display use-wear and impact marks, and are hydraulically anomalous relative to the low-energy context of the enclosing sandy silt stratum. 230Th/U radiometric analysis of multiple bone specimens using diffusion–adsorption–decay dating models indicates a burial date of 130.7 ± 9.4 thousand years ago. These findings confirm the presence of an unidentified species of Homo at the CM site during the last interglacial period (MIS 5e; early late Pleistocene), indicating that humans with manual dexterity and the experiential knowledge to use hammerstones and anvils processed mastodon limb bones for marrow extraction and/or raw material for tool production. Systematic proboscidean bone reduction, evident at the CM site, fits within a broader pattern of Palaeolithic bone percussion technology in Africa, Eurasia and North America. The CM site is, to the knowledge of the scientists, the oldest in situ, well-documented archaeological site in North America and, as such, substantially revises the timing of arrival of Homo into the Americas.

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Evidence suggests the base of Clovis fluted-points acted as "shock-absorbers" in the crafting of this iconic tool

Clovis groups, the first widely successful colonisers of North America, had a distinctive technology, whereby manufacturers removed flakes to thin the bases of their stone projectile points, creating “flutes.” That process is challenging to learn and costly to implement, yet was used continent-wide. It has long been debated whether fluting conferred any adaptive benefit. We compared standardized models of fluted and unfluted points: analytically, by way of static, linear finite element modeling and discrete, deteriorating spring modeling; and experimentally, by way of displacement-controlled axial-compression tests. We found evidence that the fluted-point base acts as a “shock absorber,” increasing point robustness and ability to withstand physical stress via stress redistribution and damage relocation. This structural gain in point resilience would have provided a selective advantage to foragers on a largely unfamiliar landscape, who were ranging far from known stone sources and in need of longer-lasting, reliable, and maintainable weaponry.

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Lower Palaeolithic stone tools have been found in Lantian County, China

The Homo erectus cranium, mandible and hundreds of associated lithic artifacts found in Lantian (central China) in the 1960s demonstrate that the area was important for hominin habitation during the early to middle Pleistocene. However, the region, which was not adequately researched until the early 2000s, still poses several questions regarding hominin behavior and lithic technology development. In this study, three loess-paleosol sequences (the Jijiawan, Ganyu and Diaozhai sites), from which in situ stone artifacts were recovered, are investigated and dated by optically stimulated luminescence (OSL), magnetostratigraphy and stratigraphic correlation. The results demonstrate that the artifacts are located within paleosol layers S4 (correlative with marine oxygen isotope stage (MIS) 11), S3 (MIS 9), S2 (MIS 7), and S1 (MIS 5); and within loess layer L1 (MIS 2–4). The main stone-knapping technique used was direct hard hammer percussion. In addition, the technological features of the stone tools found at these sites exhibit little variation, indicating the presence of a long-established, stable technology in the Lantian area. These observations show that the ancient humans lived episodically on the terraces of the Bahe River from the early Pleistocene, indicating a long history of hominin occupation of the region.

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Guidelines developed in the analysis of Ostrich eggshell remains in the archaeological record

Ostrich (Struthio spp.) eggshells are present in archaeological assemblages in many regions of Africa and Asia. However, and unlike other artifacts and ecofacts, there are no standardized guidelines for observing and recording non-ornamental ostrich eggshell. Here, a review of prior research is conducted that focuses on facets of the taphonomic history of ostrich eggshell assemblages, and we document results from our actualistic studies of the changes in color that occur when ostrich eggshells are heated. Some guidelines are proposed for recording ostrich eggshell in archaeological contexts, which include burning categories and quantification methods. These guidelines are intended to facilitate the development of large, comparative, and standardized ostrich eggshell data sets that will contribute to our understanding of site taphonomy and past human behaviour.

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The timing of the human arrival in Europe was not a matter of ecological opportunity

With an age of ∼1.6–1.5 Ma, the Early Pleistocene site of Venta Micena (Orce, Baza Basin, SE Spain) has provided the large mammals assemblage of Late Villafranchian age with higher preservational completeness in Western Europe and offers a unique opportunity to analyze the food webs of the mammalian paleocommunity before the first human arrival in this continent. Taphonomic analysis of the fossil assemblage has shown evidence of carnivore involvement, particularly hyenas, in the bone accumulating process. In this study a mathematical approach is employed based on Leslie matrices to quantify the biomass of ungulates available to the members of the carnivore guild as well as the pattern of resource partitioning and competition intensity among them. The results obtained show that although the biomass of primary consumers available to the secondary consumers was lower than the value expected under optimal conditions, more than half the individuals and biomass of carnivores expected would be reached, which allowed a viable ecosystem in Venta Micena. In fact, the biomass available for the members of the carnivore guild is 25–30% greater than the estimates obtained for two nearby sites, Barranco León-D and Fuente Nueva-3, which are somewhat younger (∼1.4 Ma) and preserve the oldest evidence on human presence in this region. Given that the competition intensity estimated in the carnivore guild of Venta Micena was lower than in the latter sites, this suggests that the timing of the first human dispersal in Western Europe was probably not a matter of ecological opportunity.

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Estimating the body size of 57 million year old primates

Obtaining accurate estimations of the body mass of fossil primates has always been a subject of interest in paleoanthropology because mass is an important determinant for so many other aspects of biology, ecology, and life history. This paper focuses on the issues involved in attempting to reconstruct the mass of two early Eocene haplorhine primates, Teilhardina and Archicebus, which pose particular problems due to their small size and temporal and phylogenetic distance from extant primates. In addition to a ranking of variables from more to less useful, the effect of using models of varying taxonomic and size compositions is examined. Phylogenetic correction is also applied to the primate database. Our results indicate that the choice of variable is more critical than the choice of model. The more reliable variables are the mediolateral breadth across the femoral condyles and the area of the calcaneocuboid facet of the calcaneus. These variables suggest a body mass of 39 g (range 33–46 g) for Archicebus and 48 g (range 44–56 g) for Teilhardina. The width of the distal femur is found to be the most consistent estimator across models of various composition and techniques. The effect of phylogenetic correction is small but the choice of branch length assumption affects point estimates for the fossils. The majority of variables and models predict the body mass of Archicebus and Teilhardina to be in the range of the smaller extant mouse lemurs, as expected.

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Palaeolithic Cave Art & Uranium Series Disequilibrium Dating

After several decades in which the evolution of Palaeolithic art seemed a settled scientific matter, new discoveries on one hand and improvements in dating methods on the other have called into question the soundness of this apparently well-founded construction. New sites and recent data, obtained by increasingly refined and precise radiometric dating techniques, have shaken the interpretive building erected mainly on the postulates of A. Leroi-Gourhan and which had stood, virtually unchanged, over the last quarter of the twentieth century. 

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Gigantopithecus blacki - The Story So Far

Gigantopithecus blacki is the largest hominoid that ever lived. The consensus view is that it is a specialized pongine and late-surviving member of the Sivapithecus-Indopithecus lineage. It is known primarily from Early and Middle Pleistocene cave sites in southern China, dating from 2.0 Ma to almost 300 ka. The cause of its extinction in the late Middle Pleistocene is unknown, but ecological change or the arrival of Homo erectus may have been contributing factors. Gigantopithecus is highly specialized in its dentognathic anatomy, with a unique combination of features that distinguish it from all other hominoids. Based on the size of its dentition and mandible, a reasonable estimate of its body mass would be 200–300 kg. There was a progressive increase in dental size from the Early Pleistocene to the Middle Pleistocene, and possibly a shift towards greater complexity of the cheek teeth. Gigantopithecus exhibits a relatively high degree of sexual dimorphism, implying a high level of male-male competition, but the relatively small canines in both sexes suggest that these teeth were not important in agonistic behaviors. The species inhabited a subtropical monsoon forest with a closed canopy and dense understory. Foraging was focused on the forest floor and its diet included a broad range of C3 plants, including fruits, leaves and stems, and possibly tubers. The cheek teeth and jaws were adapted for processing a wide variety of bulky, fibrous, and abrasive food items, but the small incisors indicate that incisal preparation was not an important part of its feeding repertoire.

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Re-examining the Mousterian of Northern Italy and Southern France

Balzi Rossi (Grimaldi) is a worldwide famous complex of Paleolithic sites located on the Franco-Italian border (Ventimiglia, Liguria). Especially known for its Upper Paleolithic occupations, each site also contained Middle Paleolithic deposits in which Mousterian evidence were early unearthed. The Museum of Prehistoric Anthropology of Monaco conserves a large part of these collections originated from Villeneuve's excavations at the end of the 19th century. This fieldwork based on forward-looking methods and commissioned by Prince Albert the 1st of Monaco involved several caves (Prince, Cavillon, and Enfants) and one shelter (Lorenzi). The few Barma Grande artefacts included were donated later on. Despite the challenges provided by this kind of assemblages, excavated over a century ago and at most composed of two thousands of pieces, it was very important to conduct an exhaustive study on these underestimated or unpublished Mousterian components. Indeed, different approaches evaluated their reliability and yielded new insights on Mousterian context and behaviors in the Balzi Rossi between MIS 5–3 embedded in new results and programs of researches.

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New hominin skull discovered in Portugal

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. 

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Evidence of craft specialisation in bead production in Upper Palaeolithic France?

The organization of beadproduction during the Aurignacian has significant implications for understanding the role of these artifacts in Upper Palaeolithic societies, and the evolution of symbolic behavior and social organization more generally. For this special issue on “The Role of Art in Prehistoric Societies,” A case study of Early Aurignacian beads in ivory and soapstone are presented, and related production debris, from four sites (Abri Castanet, Abri de la Souquette, Grotte des Hyènes at Brassempouy, Grotte d’Isturitz) in the Aquitaine region of France. The data from the case study are used to evaluate three hypothetical models of production and exchange in the given regional context, and are evaluated in terms of the current, common criteria for the recognition of craft specialization in the archaeological record. Based on these criteria, these artifacts could reasonably be considered the products of specialist producers. It is argued that the data presented here indicates two possibilities in the interpretation of prehistoric production-organization: either the presence of craft specialization in the Early Upper Palaeolithic can be accepted, or the criteria for recognizing specialization in the archaeological record should be revised. In either case, there is a demonstrated need for the refinement of models and vocabularies related to production organization in small-scale societies that better reflect the complex patterns apparent in the ethnographic and archaeological records. In addressing these issues, it is necessary to reconsider many basic assumptions about production, wealth, and exchange in Palaeolithic contexts, the perceived limitations of the archaeological record, and the nature and the antiquity of what is considered “complex” social organization. This case study and the arguments that follow are not intended to be a definitive statement on craft specialization and production organization in the Upper Palaeolithic. They are presented as an example of the kind of data-driven modeling of production and exchange in the Early Upper Palaeolithic that can serve as a concrete basis for the reconsideration of production and exchange in these contexts.

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