Carcass transport decisions in Homo antecessor subsistence strategies

Nobody's land? The oldest evidence of early Upper Paleolithic settlements in inland Iberia

The Iberian Peninsula is a key region for unraveling human settlement histories of Eurasia during the period spanning the decline of Neandertals and the emergence of anatomically modern humans (AMH). There is no evidence of human occupation in central Iberia after the disappearance of Neandertals ~42,000 years ago until approximately 26,000 years ago, rendering the region "nobody's land" during the Aurignacian period. The Abrigo de la Malia provides irrefutable evidence of human settlements dating back to 36,200 to 31,760 calibrated years before the present (cal B.P.) This site also records additional levels of occupation around 32,420 to 26,260 cal B.P., suggesting repeated settlement of this territory. Our multiproxy examination identifies a change in climate trending toward colder and more arid conditions. However, this climatic deterioration does not appear to have affected AMH subsistence strategies or their capacity to inhabit this region. These findings reveal the ability of AMH groups to colonize regions hitherto considered uninhabitable, reopening the debate on early Upper Paleolithic population dynamics of southwestern Europe.

Computer simulation of scavenging by hominins and giant hyenas in the late Early Pleistocene

Consumption of animal-sourced food is an important factor in broadening the diet of early hominins, promoting brain and body growth, and increasing behavioural complexity. However, whether early hominins obtained animal food by scavenging or hunting large mammals remains debated. Sabre-toothed felids have been proposed to facilitate the expansion of early Homo out of Africa into Europe 1.4-0.8 Ma by creating a niche for scavengers in Eurasia as the carcasses abandoned by these felids still contained abundant edible resources. In contrast, it has been argued that the niche for a large scavenger was already occupied in Eurasia by the giant hyena, preventing hominins from utilising this resource. This study shows that sabre-toothed felids generated carcasses rich in edible resources and that hominins were capable of competing with giant hyenas for this resource. The simulation experiments showed that maintaining an optimum group size is essential for the success of the hominin scavenging strategy. Early hominins could outcompete giant hyenas only if they could successfully dispute carcasses with them. Thus, in the presence of a strong competitor, passive scavenging is essentially the same as confrontational scavenging.

New evidence of Neandertal butchery traditions through the marrow extraction in southwestern Europe (MIS 5–3)

Long bone breakage for bone marrow recovery is a commonly observed practice in Middle Palaeolithic contexts, regardless of the climatic conditions. While lithic technology is largely used to define cultural patterns in human groups, despite dedicating research by zooarchaeologists, for now butchering techniques rarely allowed the identification of clear traditions, notably for ancient Palaeolithic periods. In this paper, we test the hypothesis of butchery traditions among Neandertal groupsusing the bone assemblages from three sites in southwestern Europe. These sites are located in southeastern France and northern Italy and are dated to the Late Middle Palaeolithic: Abri du Maras (Marine Isotopic Stages (MIS) 4–3, Ardèche), Saint-Marcel (MIS 3, Ardèche), and Riparo Tagliente (MIS 4–3, Verona). The detection of culturally-induced patterns of bone breakage involves differentiating them from intuitively generated patterns. To tackle this issue, we used a zooarchaeological approach focusing on the percussion marks produced during the bone breakage process. Statistical analyses as the chi-square test of independence were employed to verify if percussion mark locations were randomly distributed, and if these distributions were different from the intuitive ones. For femurs and humeri, our results demonstrate that Neandertal groups occupying the Abri du Maras (levels 4.1 and 4.2) and the Saint-Marcel Cave (levels g and h) sites in France applied butchery traditions to recover yellow marrow. However, the traditions developed at each site were different. On the contrary, in Riparo Tagliente, in Italy, several groups or individuals of a same group did not share the same butchery traditions over time. Regarding the Abri du Maras and Saint Marcel Cave assemblages, our research demonstrates that Neandertal groups applied intense standardized bone breakage, far from the intuitive practice observed experimentally and related to bone density and/or skeletal morphology. These standardized patterns, which are systematic and counter-intuitive, can be interpreted as culturally induced for the Abri du Maras and Saint Marcel Cave. The diversity of Neandertal traditions should be considered by taking into account the butchery, in particular the practice of bone marrow extraction, and not only technological behaviours and types of tool kits.

Prey Size Decline as a Unifying Ecological Selecting Agent in Pleistocene Human Evolution

We hypothesize that megafauna extinctions throughout the Pleistocene, that led to a progressive decline in large prey availability, were a primary selecting agent in key evolutionary and cultural changes in human prehistory. The Pleistocene human past is characterized by a series of transformations that include the evolution of new physiological traits and the adoption, assimilation, and replacement of cultural and behavioral patterns. Some changes, such as brain expansion, use of fire, developments in stone-tool technologies, or the scale of resource intensification, were uncharacteristically progressive. We previously hypothesized that humans specialized in acquiring large prey because of their higher foraging efficiency, high biomass density, higher fat content, and the use of less complex tools for their acquisition. Here, we argue that the need to mitigate the additional energetic cost of acquiring progressively smaller prey may have been an ecological selecting agent in fundamental adaptive modes demonstrated in the Paleolithic archaeological record. We describe several potential associations between prey size decline and specific evolutionary and cultural changes that might have been driven by the need to adapt to increased energetic demands while hunting and processing smaller and smaller game.

The Neanderthal teeth from Marillac (Charente, Southwestern France): Morphology, comparisons and paleobiology

Few European sites have yielded human dental remains safely dated to the end of MIS 4/beginning of MIS 3. One of those sites is Marillac (Southwestern France), a collapsed karstic cave where archeological excavations (1967-1980) conducted by B. Vandermeersch unearthed numerous faunal and human remains, as well as a few Mousterian Quina tools. The Marillac sinkhole was occasionally used by humans to process the carcasses of different prey, but there is no evidence for a residential use of the site, nor have any hearths been found. Rare carnivore bones were also discovered, demonstrating that the sinkhole was seasonally used, not only by Neanderthals, but also by predators across several millennia. The lithostratigraphic units containing the human remains were dated to ∼60 kyr. The fossils consisted of numerous fragments of skulls and jaws, isolated teeth and several post-cranial bones, many of them with traces of perimortem manipulations. For those already published, their morphological characteristics and chronostratigraphic context allowed their attribution to Neanderthals. This paper analyzes sixteen unpublished human teeth (fourteen permanent and two deciduous) by investigating the external morphology and metrical variation with respect to other Neanderthal remains and a sample from modern populations. We also investigate their enamel thickness distribution in 2D and 3D, the enamel-dentine junction morphology (using geometric morphometrics) of one molar and two premolars, the roots and the possible expression of taurodontism, as well as pathologies and developmental defects. The anterior tooth use and paramasticatory activities are also discussed. Morphological and structural alterations were found on several teeth, and interpreted in light of human behavior (tooth-pick) and carnivores' actions (partial digestion). The data are interpreted in the context of the available information for the Eurasian Neanderthals.

Shedding light on the Early Pleistocene of TD6 (Gran Dolina, Atapuerca, Spain): The technological sequence and occupational inferences

This paper aims to update the information available on the lithic assemblage from the entire sequence of TD6 now that the most recent excavations have been completed, and to explore possible changes in both occupational patterns and technological strategies evidenced in the unit. This is the first study to analyse the entire TD6 sequence, including subunits TD6.3 and TD6.1, which have never been studied, along with the better-known TD6.2 Homo antecessor-bearing subunit. We also present an analysis of several lithic refits found in TD6, as well as certain technical features that may help characterise the hominin occupations. The archaeo-palaeontological record from TD6 consists of 9,452 faunal remains, 443 coprolites, 1,046 lithic pieces, 170 hominin remains and 91 Celtis seeds. The characteristics of this record seem to indicate two main stages of occupation. In the oldest subunit, TD6.3, the lithic assemblage points to the light and limited hominin occupation of the cave, which does, however, grow over the course of the level. In contrast, the lithic assemblages from TD6.2 and TD6.1 are rich and varied, which may reflect Gran Dolina cave’s establishment as a landmark in the region. Despite the occupational differences between the lowermost subunit and the rest of the deposit, technologically the TD6 lithic assemblage is extremely homogeneous throughout. In addition, the composition and spatial distribution of the 12 groups of lithic refits found in unit TD6, as well as the in situ nature of the assemblage demonstrate the high degree of preservation at the site. This may help clarify the nature of the Early Pleistocene hominin occupations of TD6, and raise reasonable doubt about the latest interpretations that support the ex situ character of the assemblage as a whole.

Neanderthal hunting strategies inferred from mortality profiles within the Abric Romaní sequence

Ungulate mortality profiles are commonly used to study Neanderthal subsistence strategies. To assess the hunting strategies used by Neanderthals, we studied the ages at death of the cervids and equids found in levels E, H, I, Ja, Jb, K, L and M of the Abric Romaní sequence. These levels date between 43.2 ± 1.1 ka BP (¹⁴C AMS) and 54.5 ± 1.7 ka BP (U-series). The degree of eruption and development of the teeth and their wear stages were used to determine the ages of these animals at death, and mortality profiles were constructed using these data. The equids display prime dominated profiles in all of the analyzed levels, whereas the cervids display variable profiles. These results suggest that the Neanderthals of Abric Romaní employed both selective and non-selective hunting strategies. The selective strategy focused on the hunting of prime adults and generated prime dominated profiles. On the other hand, non-selective strategies, involved the consumption of animals of variable ages, resulting in catastrophic profiles. It is likely that in the selective hunting events were conducted using selective ambushes in which it was possible to select specific prey animals. On the other hand, encounter hunting or non-selective ambush hunting may have also been used at times, based on the abundances of prey animals and encounter rates. Specific hunting strategies would have been developed accordance with the taxa and the age of the individual to be hunted. The hunting groups most likely employed cooperative hunting techniques, especially in the capture of large animals. Thus, it is not possible to uniquely associate a single mortality profile with the predation tactics of Neanderthals at Abric Romaní.

The diet of the first Europeans from Atapuerca

Hominin dietary specialization is crucial to understanding the evolutionary changes of craniofacial biomechanics and the interaction of food processing methods’ effects on teeth. However, the diet-related dental wear processes of the earliest European hominins remain unknown because most of the academic attention has focused on Neandertals. Non-occlusal dental microwear provides direct evidence of the effect of chewed food particles on tooth enamel surfaces and reflects dietary signals over time. Here, we report for the first time the direct effect of dietary abrasiveness as evidenced by the buccal microwear patterns on the teeth of the Sima del Elefante-TE9 and Gran Dolina-TD6 Atapuerca hominins (1.2–0.8 million years ago − Myr) as compared with other Lower and Middle Pleistocene populations. A unique buccal microwear pattern that is found in Homo antecessor (0.96–0.8 Myr), a well-known cannibal species, indicates dietary practices that are consistent with the consumption of hard and brittle foods. Our findings confirm that the oldest European inhabitants ingested more mechanically-demanding diets than later populations because they were confronted with harsh, fluctuating environmental conditions. Furthermore, the influence of grit-laden food suggests that a high-quality meat diet from butchering processes could have fueled evolutionary changes in brain size.

New interpretation of the Gran Dolina-TD6 bearing Homo antecessor deposits through sedimentological analysis

Gran Dolina is a cavity infilled by at least 25 m of Pleistocene sediments. This sequence contains the TD6 stratigraphic unit, whose records include around 170 hominin bones that have allowed the definition of a new species, Homo antecessor. This fossil accumulation was studied as a single assemblage and interpreted as a succession of several human home bases. We propose a complete stratigraphic context and sedimentological interpretation for TD6, analyzing the relationships between the sedimentary facies, the clasts and archaeo-palaeontological remains. The TD6 unit has been divided into three sub-units and 13 layers. Nine sedimentary facies have been defined. Hominin remains appear related to three different sedimentary facies: debris flow facies, channel facies and floodplain facies. They show three kinds of distribution: first a group of scattered fossils, then a group with layers of fossils in fluvial facies, and third a group with a layer of fossils in mixed fluvial and gravity flow facies. The results of this work suggest that some of these hominin remains accumulated in the cave by geological processes, coming from the adjacent slope above the cave or the cave entry, as the palaeogeography and sedimentary characteristics of these allochthonous facies suggest.

Manual Loading Distribution During Carrying Behaviors: Implications for the Evolution of the Hominin Hand

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.

Excavations at Schöningen and paradigm shifts in human evolution

The exceptional preservation at Schöningen together with a mixture of perseverance, hard work, and sheer luck led to the recovery of unique finds in an exceptional context. The 1995 discovery of numerous wooden artifacts, most notably at least 10 carefully made spears together with the skeletons of at least 20 to 25 butchered horses, brought the debate about hunting versus scavenging among late archaic hominins and analogous arguments about the purportedly primitive behavior of Homo heidelbergensis and Neanderthals to an end. Work under H. Thieme's lead from 1992 to 2008 and results from the current team since 2008 demonstrate that late H. heidelbergensis or early Neanderthals used sophisticated artifacts made from floral and faunal materials, in addition to lithic artifacts more typically recovered at Lower Paleolithic sites. The finds from the famous Horse Butchery Site and two dozen other archaeological horizons from the edges of the open-cast mine at Schöningen provide many new insights into the technology and behavioral patterns of hominins about 300 ka BP during MIS 9 on the Northern European Plain. An analysis of the finds from Schöningen and their contexts shows that the inhabitants of the site were skilled hunters at the top of the food chain and exhibited a high level of planning depth. These hominins had command of effective means of communication about the here and now, and the past and the future, that allowed them to repeatedly execute well-coordinated and successful group activities that likely culminated in a division of labor and social and economic patterns radically different from those of all non-human primates. The unique preservation and high quality excavations have led to a major paradigm shift or "Schöningen Effect" that changed our views of human evolution during the late Lower Paleolithic. In this respect, we can view the behaviors documented at Schöningen as a plausible baseline for the behavioral sophistication of archaic hominins of the late Middle Pleistocene and subsequent periods.

Experimental butchering of a chimpanzee carcass for archaeological purposes

Two archaeological assemblages from the Sierra de Atapuerca sites show evidence of anthropogenic cannibalism. These are the late Early Pleistocene level TD6-2 at Gran Dolina, and the Bronze Age level MIR4 in the Mirador Cave. Despite the chronological distance between these two assemblages, they share the common feature that the human remains exhibit a high frequency of anthropogenic modifications (cut marks, percussion pits and notches and peeling). This frequency could denote special treatment of bodies, or else be the normal result of the butchering process. In order to test these possibilities, we subjected a chimpanzee carcass to a butchering process. The processing was intensive and intended to simulate preparation for consumption. In doing this, we used several simple flakes made from quartzite and chert from quarries in the Sierra de Atapuerca. The skull, long bones, metapodials and phalanges were also fractured in order to remove the brain and bone marrow. As a result, about 40% of the remains showed some kind of human modification. The frequency, distribution and characteristics of these modifications are very similar to those documented on the remains of Homo antecessor from TD6-2. In case of the MIR4 assemblage, the results are similar except in the treatment of skulls. Our results indicate that high frequencies of anthropogenic modifications are common after an intensive butchering process intended to prepare a hominin body for consumption in different contexts (both where there was possible ritual behavior and where this was not the case and the modifications are not the result of special treatment).

Discontinuity of human presence at Atapuerca during the early Middle Pleistocene: a matter of ecological competition?

Increasing evidence suggests that the European human settlement is older than 1.2 Ma. However, there is a fierce debate about the continuity or discontinuity of the early human settlement of Europe. In particular, evidence of human presence in the interval 0.7-0.5 Ma is scarce in comparison with evidence for the previous and later periods. Here, we present a case study in which the environmental conditions at Sierra de Atapuerca in the early Middle Pleistocene, a period without evidence of human presence, are compared with the conditions in the previous period, for which a relatively intense human occupation is documented. With this objective in mind, the available resources for a human population and the intensity of competition between secondary consumers during the two periods are compared using a mathematical model. The Gran Dolina site TD8 level, dated to 0.7-0.6 Ma, is taken as representative of the period during which Atapuerca was apparently not occupied by humans. Conditions at TD8 are compared with those of the previous period, represented by the TD6-2 level, which has yielded abundant evidence of intense human occupation. The results show that survival opportunities for a hypothetical human population were lower at TD8 than they were at TD6-2. Increased resource competition between secondary consumers arises as a possible explanation for the absence of human occupation at Atapuerca in the early Middle Pleistocene.

A model of hunter-gatherer skeletal element transport: the effect of prey body size, carriers, and distance

Zooarchaeologists frequently use the relative abundance of skeletal elements in faunal assemblages in conjunction with foraging theory models to infer subsistence decisions made by prehistoric hunter-gatherers. However, foraging models applied to ethnoarchaeological cases have had variable success linking skeletal transport decisions with foraging predictions. Here, we approach this issue with the well-known Hadza data to statistically model the skeletal element transport decisions in response to distance from the residential hub and the number of carriers available for carcass transport. We compare our modeling approach to the traditional skeletal element utility curves from Binford's work with the Nunamiut, and to the more recently proposed Shannon evenness measure. Our approach, based on standard yet powerful statistical modeling techniques, can help researchers gain increased insight into the prey part transport responses of hunter-gatherers. Our analyses treat individual prey skeletal elements by body size as the response variable. The results of this analysis suggest that utility curves, and the Shannon evenness approach as a proxy for utility curves, are problematic for making statements about prehistoric foraging from zooarchaeological data. Transport distance does not explain a significant portion of small prey (size class 2) skeletal element transport variation. However, distance explains a great deal of transport variation in large prey (size classes 4 and 5). Inferences from skeletal element profiles should be made relative to prey body size and the discard probability of individual elements. Understanding the influence of these variables allows construction of a framework for testing archaeological element profiles against ethnographically derived transport models.

Modeling trophic resource availability for the first human settlers of Europe: the case of Atapuerca TD6

Food resource availability strongly influences the survival opportunities of all organisms. The effect of animal food resource availability on the survival and dispersal of hominin populations is hotly debated. In this article, we present a mathematical model that provides estimations of the maximum and minimum available resources for secondary consumers in a palaeocommunity. This model provides insights into the intensity of competition and the available niche space for hominins in Europe during the early Galerian (1.2-0.8 Ma). Published data from the Atapuerca TD6 assemblage were used in combination with the model to investigate trophic dynamics and resource availability for a Homo antecessor population 800,000 years ago. The effect on our results of the possible presence at Atapuerca of some large carnivores not recorded in the fossil assemblage is also evaluated. Results indicate the existence of a rich ecosystem at Atapuerca at the end of the Early Pleistocene. Secondary production was abundant enough to maintain a hunter-gatherer population and a rich carnivore guild more diverse than that recorded in the TD6 assemblage. Based on these results, the practice of cannibalism by H. antecessor cannot be explained by a long-term scarcity of resources. High food availability at TD6 implies a low to moderate level of competition for resources between carnivores and humans. According to this interpretation, an empty niche for a highly carnivorous omnivore existed in Europe during the early Galerian, and it was successfully exploited by Homo.