Taphonomic skeletal disturbances in the Sima de los Huesos postcranial remains.

The postcranial skeleton of fossil hominins is crucial for reconstructing the processes that occurred between the time of death and the recovery of the bones. Thousands of postcranial skeletal fragments from at least 29 hominin individuals have been recovered from the Sima de los Huesos Middle Pleistocene site in Spain. This study's primary objective is to address the main taphonomic features of the postcranial remains from the Sima de los Huesos sample, including antemortem, perimortem, and postmortem skeletal disturbances. We present an updated assessment of the bone surface modification analysis, the fracture pattern analysis, and the skeletal part representation to facilitate interpretation of the biostratinomic and fossil-diagenetic processes in this large paleoanthropological collection. We conclude that carnivores (probably bears) had limited access to the hominin bones and complete bodies were probably placed in the site.

Taphonomic-forensic analysis of the hominin skulls from the Sima de los Huesos.

The Sima de los Huesos (SH) hominin assemblage is composed of thousands of fossil fragments, including pieces of crania and mandibles. The main objective of this work is to address the main taphonomic features of the cranial and mandibular remains from the SH sample, including antemortem, perimortem, and postmortem skeletal disturbances. We present an updated assessment of healed cranial trauma, first described in 1997 and now including new skulls. In addition, this study reviews the perimortem fractures in relation to their location and features of the affected individuals. Finally, this paper deals with the modifications affecting the cranial sample from the SH at the postmortem stage, including physical and biological postdepositional modifications. The SH collection provides a unique opportunity for conducting a complete forensic-taphonomic study on a Middle Pleistocene population.

Unearthing Neanderthal population history using nuclear and mitochondrial DNA from cave sediments.

Bones and teeth are important sources of Pleistocene hominin DNA, but are rarely recovered at archaeological sites. Mitochondrial DNA (mtDNA) has been retrieved from cave sediments but provides limited value for studying population relationships. We therefore developed methods for the enrichment and analysis of nuclear DNA from sediments and applied them to cave deposits in western Europe and southern Siberia dated to between 200,000 and 50,000 years ago. We detected a population replacement in northern Spain about 100,000 years ago, which was accompanied by a turnover of mtDNA. We also identified two radiation events in Neanderthal history during the early part of the Late Pleistocene. Our work lays the ground for studying the population history of ancient hominins from trace amounts of nuclear DNA in sediments.

Issues of theory and method in the analysis of Paleolithic mortuary behavior: A view from Shanidar Cave.

Mortuary behavior (activities concerning dead conspecifics) is one of many traits that were previously widely considered to have been uniquely human, but on which perspectives have changed markedly in recent years. Theoretical approaches to hominin mortuary activity and its evolution have undergone major revision, and advances in diverse archeological and paleoanthropological methods have brought new ways of identifying behaviors such as intentional burial. Despite these advances, debates concerning the nature of hominin mortuary activity, particularly among the Neanderthals, rely heavily on the rereading of old excavations as new finds are relatively rare, limiting the extent to which such debates can benefit from advances in the field. The recent discovery of in situ articulated Neanderthal remains at Shanidar Cave offers a rare opportunity to take full advantage of these methodological and theoretical developments to understand Neanderthal mortuary activity, making a review of these advances relevant and timely.

The human remains from Axlor (Dima, Biscay, northern Iberian Peninsula).

OBJECTIVES: We provide the description and comparative analysis of all the human fossil remains found at Axlor during the excavations carried out by J. M. de Barandiarán from 1967 to 1974: a cranial vault fragment and seven teeth, five of which likely belonged to the same individual, although two are currently lost. Our goal is to describe in detail all these human remains and discuss both their taxonomic attribution and their stratigraphic context. MATERIALS AND METHODS: We describe external and internal anatomy, and use classic and geometric morphometrics. The teeth from Axlor are compared to Neandertals, Upper Paleolithic, and recent modern humans. RESULTS: Two teeth (a left dm2 , a left di1 ) and the parietal fragment show morphological features consistent with a Neandertal classification, and were found in an undisturbed Mousterian context. The remaining three teeth (plus the two lost ones), initially classified as Neandertals, show morphological features and a general size that are more compatible with their classification as modern humans. DISCUSSION: A left parietal fragment (Level VIII) from a single probably adult Neandertal individual was recovered during the old excavations performed by Barandiarán. Additionally, two different Neandertal children lost deciduous teeth during the formations of levels V (left di1 ) and IV (right dm2 ). In addition, a modern human individual is represented by five remains (two currently lost) from a complex stratigraphic setting. Some of the morphological features of these remains suggest that they may represent one of the scarce examples of Upper Paleolithic modern human remains in the northern Iberian Peninsula, which should be confirmed by direct dating.

New bracketing luminescence ages constrain the Sima de los Huesos hominin fossils (Atapuerca, Spain) to MIS 12.

Recent chronological studies of the Sima de los Huesos (SH) hominin fossil site, Atapuerca, Spain, have established a close minimum age of at least 430 ka for sedimentary material immediately overlying the human remains. However, a firm maximum age limit still needs to be established for the SH fossils in order to better constrain the timing for the onset of Neandertal speciation. In the present study, we address this important chronological gap at SH by providing direct ages for the sediment deposits that host, and immediately underlie, the hominin fossils. Depositional ages were obtained using single-grain thermally-transferred optically stimulated luminescence (TT-OSL), a technique that has yielded reliable 'extended-range' luminescence chronologies at several independently dated Atapuerca sites. Four single-grain TT-OSL depositional ages of 453 ± 56 ka, 437 ± 38 ka, 457 ± 41 ka and 460 ± 39 ka were obtained for the red clay lithostratigraphic units (LU-5 and LU-6) found underlying and encasing the SH hominin bones. A Bayesian age-depth model was constructed using previously published chronologies, as well as the new single-grain TT-OSL ages for LU-5 and LU-6, in order to derive combined age estimates for individual lithostratigraphic units preserved at SH. The combined modeled ranges reveal that the hominin-bearing layer (LU-6) was deposited between 455 ± 17 ka and 440 ± 15 ka (mean lower and upper boundary 68.2% probability range ± 1σ uncertainty, respectively), with a mean age of 448 ± 15 ka. These new bracketing ages suggest that the hominin fossils at SH were most likely deposited within Marine Isotope Stage (MIS) 12, enabling more precise temporal constraint on the early evolution of the Neandertal lineage. The SH fossils represent the oldest reliably dated hominin remains displaying Neandertal features across Eurasia. These Neandertal features are first observed in the facial skeleton, including the mandible and teeth, as well as the temporomandibular joint, and appear consistently across the SH collection. Our chronological findings suggest that the appearance of these Neandertal traits may have been associated with the climatic demise of MIS 12 and the ecological changes that occurred in Iberia during this period. Other Middle Pleistocene hominin fossils from Europe dated to MIS 12-11, or later, show different morphological trends, with some lacking Neandertal specializations. The latest SH dating results enable improved temporal correlations with these contrasting hominin records from Europe, and suggest a complex picture for hominin evolution during the Middle Pleistocene.

Taphonomic inferences about Middle Pleistocene hominins: The human cranium of Gruta da Aroeira (Portugal).

OBJECTIVES: The aim of this work is to describe the taphonomic signatures of the Aroeira 3 cranium, with a specific focus on cranial breakage, comparing the cranium with other Middle and Upper Pleistocene hominin fossils in order to approximate the cause of death and the biological agencies and geologic processes involved in the taphonomic record of this specimen. Aroeira-3 was recovered from Acheulean layer X of Gruta da Aroeira (Portugal), dated to 390-436 ka. MATERIALS AND METHODS: Taphonomic analyses noted surface modifications employing standard methods. The cranial breakage pattern of Aroeira 3 was analyzed to assess the presence/absence of perimortem (fresh bone) and postmortem (dry bone) fractures and the possible causes of perimortem skull bone fractures. RESULTS: Aroeira 3 presents substantial bone loss of the left supraorbital arch and the outer cranial table of the frontal squama. Most of the fractures present features consistent with postmortem injuries. The fracture to the posterior region of the parietal bone, however, displays features more usually present in perimortem bone fractures. No evidence of anthropogenic activity or of carnivore modification has been identified. None of the expected features of interpersonal conflict are observed. Finally, the bone loss in the frontal squama and the supraorbital arch could be attributed to different agencies, and a traumatic event cannot be totally ruled out as origin of the bone alteration. DISCUSSION: Cannibalism, secondary treatment of the corpse and accumulation induced by carnivores can all be discarded, making an accident the most plausible explanation for the cranial fracture.

First data of Neandertal bird and carnivore exploitation in the Cantabrian Region (Axlor; Barandiaran excavations; Dima, Biscay, Northern Iberian Peninsula).

Neandertals were top predators who basically relied on middle- to large-sized ungulates for dietary purposes, but there is growing evidence that supports their consumption of plants, leporids, tortoises, marine resources, carnivores and birds. The Iberian Peninsula has provided the most abundant record of bird exploitation for meat in Europe, starting in the Middle Pleistocene. However, the bird and carnivore exploitation record was hitherto limited to the Mediterranean area of the Iberian Peninsula. Here we present the first evidence of bird and carnivore exploitation by Neandertals in the Cantabrian region. We have found cut-marks in two golden eagles, one raven, one wolf and one lynx remain from the Mousterian levels of Axlor. The obtaining of meat was likely the primary purpose of the cut-marks on the golden eagle and lynx remains. Corvids, raptors, felids and canids in Axlor could have likely acted as commensals of the Neandertals, scavenging upon the carcasses left behind by these hunter-gatherers. This could have brought them closer to Neandertal groups who could have preyed upon them. These new results provide additional information on their dietary scope and indicate a more complex interaction between Neandertals and their environment.

La Ferrassie 1: New perspectives on a "classic" Neandertal.

The La Ferrassie 1 (LF1) skeleton, discovered over a century ago, is one of the most important Neandertal individuals both for its completeness and due to the role it has played historically in the interpretation of Neandertal anatomy and lifeways. Here we present new skeletal remains from this individual, which include a complete right middle ear ossicular chain (malleus, incus, and stapes), three vertebral fragments, and two costal remains. Additionally, the study of the skeleton has allowed us to identify new pathological lesions, including a congenital variant in the atlas, a greenstick fracture of the left clavicle, and a lesion in a mid-thoracic rib of unknown etiology. In addition, we have quantified the amount of vertebral pathology, which is greater than previously appreciated. We have complemented the paleopathological analysis with a taphonomic analysis to identify any potential perimortem fractures. The taphonomic analysis indicates that no surface alteration is present in the LF1 skeleton and that the breakage pattern is that of bone that has lost collagen, which would be consistent with the intentional burial of this individual proposed by previous researchers. In this study, we used CT and microCT scans in order to discover new skeletal elements to better characterize the pathological lesions and to quantify the fracture orientation of those bones in which the current plaster reconstruction did not allow its direct visualization, which underlines the broad potential of imaging technologies in paleoanthropological research. A century after its discovery, LF1 is still providing new insights into Neandertal anatomy and behavior.

Postcranial morphology of the middle Pleistocene humans from Sima de los Huesos, Spain.

Current knowledge of the evolution of the postcranial skeleton in the genus Homo is hampered by a geographically and chronologically scattered fossil record. Here we present a complete characterization of the postcranium of the middle Pleistocene paleodeme from the Sima de los Huesos (SH) and its paleobiological implications. The SH hominins show the following: (i) wide bodies, a plesiomorphic character in the genus Homo inherited from their early hominin ancestors; (ii) statures that can be found in modern human middle-latitude populations that first appeared 1.6-1.5 Mya; and (iii) large femoral heads in some individuals, a trait that first appeared during the middle Pleistocene in Africa and Europe. The intrapopulational size variation in SH shows that the level of dimorphism was similar to modern humans (MH), but the SH hominins were less encephalized than Neandertals. SH shares many postcranial anatomical features with Neandertals. Although most of these features appear to be either plesiomorphic retentions or are of uncertain phylogenetic polarity, a few represent Neandertal apomorphies. Nevertheless, the full suite of Neandertal-derived features is not yet present in the SH population. The postcranial evidence is consistent with the hypothesis based on the cranial morphology that the SH hominins are a sister group to the later Neandertals. Comparison of the SH postcranial skeleton to other hominins suggests that the evolution of the postcranium occurred in a mosaic mode, both at a general and at a detailed level.

Lethal interpersonal violence in the Middle Pleistocene.

Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force trauma. The type of injuries, their location, the strong similarity of the fractures in shape and size, and the different orientations and implied trajectories of the two fractures suggest they were produced with the same object in face-to-face interpersonal conflict. Given that either of the two traumatic events was likely lethal, the presence of multiple blows implies an intention to kill. This finding shows that the lethal interpersonal violence is an ancient human behavior and has important implications for the accumulation of bodies at the site, supporting an anthropic origin.

Human calcanei from the Middle Pleistocene site of Sima de los Huesos (Sierra de Atapuerca, Burgos, Spain).

The existence of calcanei in the fossil record prior to modern humans and Neandertals is very scarce. This skeletal element is fundamental to understanding the evolution of the morphology of the foot in human evolution. Here we present and metrically and comparatively describe 29 calcaneus remains from the Middle Pleistocene site of Sima de los Huesos (SH) (Sierra de Atapuerca, Burgos, Spain). These calcanei belong to 15 individuals (nine adults, two adolescents and four immature individuals). The metric and morphological differences in the calcanei among Middle and Late Pleistocene hominins tend to be subtle. However, the calcanei from SH are broad and robust with large articular surfaces and most significantly, exhibit a very projected sustentaculum tali. A biomechanical and phylogenetic interpretation is proffered to explain the observed morphology of these calcanei. It has been possible to propose tentative sex assignments for the SH calcanei based on size, using methods similar to those used to establish sex from the talus bones from SH. The estimation of stature based on the calcaneus provides a mean of 175.3 cm for males and 160.6 for females, which is similar to that obtained using other skeletal parts from the site. In sum, the SH calcanei are robust with a proportionally long tubercle and a projected sustentaculum tali, which are traits shared by Neandertals.

Human talus bones from the Middle Pleistocene site of Sima de los Huesos (Sierra de Atapuerca, Burgos, Spain).

Here we present and describe comparatively 25 talus bones from the Middle Pleistocene site of the Sima de los Huesos (SH) (Sierra de Atapuerca, Burgos, Spain). These tali belong to 14 individuals (11 adult and three immature). Although variation among Middle and Late Pleistocene tali tends to be subtle, this study has identified unique morphological characteristics of the SH tali. They are vertically shorter than those of Late Pleistocene Homo sapiens, and show a shorter head and a broader lateral malleolar facet than all of the samples. Moreover, a few shared characters with Neanderthals are consistent with the hypothesis that the SH population and Neanderthals are sister groups. These shared characters are a broad lateral malleolar facet, a trochlear height intermediate between modern humans and Late Pleistocene H. sapiens, and a short middle calcaneal facet. It has been possible to propose sex assignment for the SH tali based on their size. Stature estimates based on these fossils give a mean stature of 174.4 cm for males and 161.9 cm for females, similar to that obtained based on the long bones from this same site.