Lethal interpersonal violence in the Middle Pleistocene

The evolution of human music in light of increased prosocial behavior: a new model

Together with language, music is perhaps our most distinctive behavioral trait. Following the lead of evolutionary linguistic research, different hypotheses have been proposed to explain why only humans perform music and how this ability might have evolved in the species. In this paper, we advance a new model of music evolution that builds on the theory of self-domestication, according to which the human phenotype is, at least in part, the outcome of a process similar to mammal domestication, triggered by a progressive reduction in reactive aggression levels in response to environmental changes. In the paper, we specifically argue that changes in aggression management through the course of human cultural evolution can account for the behaviors conducive to the emergence and evolution of music. We hypothesize 4 stages in the evolutionary development of music under the influence of environmental changes and evolution of social organization: starting from musilanguage, 1) proto-music gave rise to 2) personal and private forms of timbre-oriented music, then to 3) small-group ensembles of pitch-oriented music, at first of indefinite and then definite pitch, and finally to 4) collective (tonal) music. These stages parallel what has been hypothesized for languages and encompass the diversity of music types and genres described worldwide. Overall, music complexity emerges in a gradual fashion under the effects of enhanced abilities for cultural niche construction, resulting from the stable trend of reduction in reactive aggression towards the end of the Pleistocene, leading to the rise of hospitality codes, and succeeded by the increase in proactive aggression from the beginning of the Holocene onward. This paper addresses numerous controversies in the literature on the evolution of music by providing a clear structural definition of music, identifying its structural features that distinguish it from oral language, and summarizing the typology of operational functions of music and formats of its transmission. The proposed framework of structural approach to music arms a researcher with means to identify and comparatively analyze different schemes of tonal organization of music, placing them in the context of human social and cultural evolution. Especially valuable is the theory of so-called "personal song", described and analyzed here from ethological, social, cultural, cognitive, and musicological perspectives. Personal song seems to constitute a remnant of the proto-musical transition from animal communication to human music as we know it today. We interlink the emergence of personal song with the evolution of kinship, placing both of them on the timeline of cultural evolution - based on totality of ethnographic, archaeological, anthropological, genetic, and paleoclimatic data.

The Origins of War : A Global Archaeological Review

How old is war? Is it a deep-seated propensity in the human species or is it a recent cultural invention? This article investigates the archaeological evidence for prehistoric war across world regions by probing two competing hypotheses. The "deep roots" thesis asserts that war is an evolved adaptation that humans inherited from their common ancestor with chimpanzees, from which they split around seven million years ago, and that persisted throughout prehistory, encompassing both nomadic and sedentary hunter-gatherer societies. In contrast, the "shallow roots" viewpoint posits that peaceful intergroup relations are ancestral in humans, suggesting that war emerged only recently with the development of sedentary, hierarchical, and densely populated societies, prompted by the agricultural revolution ~ 12,000-10,000 years ago. To ascertain which position is best supported by the available empirical evidence, this article reviews the prehistoric archaeological record for both interpersonal and intergroup conflict across world regions, following an approximate chronological sequence from the emergence of humans in Africa to their dispersal out of Africa in the Near East, Europe, Australia, Northeast Asia, and the Americas. This worldwide analysis of the archaeological record lends partial support to both positions, but neither the "deep roots" nor the "shallow roots" argument is fully vindicated. Intergroup relations among prehistoric hunter-gatherers were marked neither by relentless war nor by unceasingly peaceful interactions. What emerges from the archaeological record is that, while lethal violence has deep roots in the Homo lineage, prehistoric group interactions-ranging from peaceful cooperation to conflict-exhibited considerable plasticity and variability, both over time and across world regions, which constitutes the true evolutionary puzzle.

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.

Metatarsals and foot phalanges from the Sima de los Huesos Middle Pleistocene site (Atapuerca, Burgos, Spain)

This study provides a complete, updated and illustrated inventory, as well as a comprehensive study, of the metatarsals and foot phalanges (forefoot) recovered from the Middle Pleistocene site of Sima de los Huesos (SH, Atapuerca, Spain) in comparison to other Homo comparative samples, both extant and fossils. This current updated review has established a minimum number of individuals (MNI) of 17, which represent 58.6% of the 29 dental individuals identified within the SH sample. An exclusive or autoapomorphic combination of traits can be recognized within the SH hominin foot sample. A few traits appear primitive or plesiomorphic when compared with earlier Homo individuals and other recent modern humans. There are other metrical and morphological traits that SH hominins and Neandertals have in common that sometimes represent shared derived traits in this evolutionary line, most of which are probably related to robusticity. Furthermore, some exclusive autoapomorphic traits are observed in the SH sample: a very broad first metatarsal, long and broad hallucal proximal foot phalanges and possibly extremely robust lateral distal foot phalanges compared to those of Neandertals and modern humans. In these last traits, the SH metatarsals and pedal phalanges are even more robust than in Neandertals. They are herein named as "hyper-Neandertal" traits, which could suggest a slight gracilization process in this evolutionary line, at least in the hallux toe. Finally, some paleobiological inferences are made in relation to body size (stature and body mass) and some associations are proposed within the SH sample.

Tarsals from the Sima de los Huesos Middle Pleistocene site (Atapuerca, Burgos, Spain)

Here, we provide a complete, updated, and illustrated inventory, as well as a comprehensive study, of the tarsals (rearfoot) recovered from the Middle Pleistocene site of Sima de los Huesos (SH, Atapuerca, Spain) in comparison to other Homo comparative samples, both extant and fossil. The minimum number of individuals (MNI) estimated from the tarsals has been established as 15, which represents 51.7% of the 29 dental individuals identified within the SH sample. Within the SH hominin foot sample, an exclusive combination of primitive or plesiomorphic and derived or autapomorphic traits can be observed when compared with other Homo individuals/populations. Other characters are shared among SH hominins and Neandertals that might represent shared derived or autapomorphic traits for this evolutionary line, and most are likely related to robusticity (e.g., rectangular-like trochlea of the talus, broad calcanei, broad naviculars, and short lateral cuneiforms). Additionally, we observed some exclusive autapomorphic traits in the SH tarsal sample (e.g., narrow head of the talus and short intermediate cuneiforms). A few exclusive traits in SH tarsal remains are even more robust than in Neandertals (e.g., broad lateral malleolar facet in talus, more projected sustentaculum tali, and broad medial cuneiform). These traits could suggest a slightly higher level of gracilization in the tarsal bones of Neandertals compared to the SH sample that is also supported by other anatomical postcranial skeleton elements. Additionally, some paleobiological inferences are made in relation to body size (stature and body mass) and some associations are proposed within the SH sample. In conclusion, the morphology of the SH tarsi confirms an evolutionary relationship of sister groups between this population and Neandertals, probably representing a morphotype similar to the Neandertal ancestors.

How the Sima de los Huesos was won

Although the first discovery of a human fossil in the Sima de los Huesos took place in 1976, systematic excavations did not begin there until 1984. Since then, this site has been continuously excavated in month-long camps. The site is dated by different radiometric techniques to between 430,000 and 300,000 years ago. Until the 2023 campaign, just over 7000 human fossils have been recovered, constituting the largest collection of fossils prior to Homo sapiens ever discovered. The fossils correspond to a minimum of 29 individuals of both sexes and different ages at death, from preadolescents to a specimen of advanced age. Comparative anatomy and ancient DNA studies both suggest that this is a population closely related to Homo neanderthalensis. The great variety and extraordinary quality of the fossils recovered have allowed us to carry out a series of investigations that have greatly increased our knowledge about the evolution of Homo in the Middle Pleistocene. Among the most important discoveries, it has been possible to establish body size and proportions, the confirmation that the origin of the accumulation of human fossils was of an anthropic nature, that those past humans took care of disabled individuals and who were capable of having an oral language almost as complex and efficient as that of our own species.

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.

Fusion of the occipitomastoidal synchondrosis as a developmental marker in the Sima de los Huesos Crania (Atapuerca, Spain)

The basicranium contains multiple synchondroses potentially informative for estimating the developmental stage of individuals. The basilar synchondrosis has been routinely used for this purpose in bioarchaeological, forensic and paleoanthropological research, and studies carried out in modern human populations have shown a close relationship between the fusion of the occipitomastoidal synchondrosis and developmental processes. This synchondrosis articulates the jugular process of the occipital bone with the jugular surface of the temporal bone. As the process of fusion of the synchondrosis progresses, the jugular surface undergoes a series of alterations whose study allows to establish the state of fusion of the synchondrosis when the individual died. The extraordinary preservation of the jugular surface in a large number of individuals represented in the fossil hominin sample from the middle Pleistocene site of the Sima de los Huesos (SH) has made it possible to carry out the first systematic study to assess the usefulness of occipitomastoidal synchondrosis in the establishment of the state of development in fossil hominins. Our results show that the complete closure of the occipitomastoidal synchondrosis occurred toward the end of the growth period in the SH fossils. This result opens up the possibility of using it to determine the developmental stage of fossil hominins for which no other information is available, such as the state of the dentition or the degree of closure of the basilar synchondrosis. This has allowed us to infer a state of development for three SH crania where it could not previously be established with certainty.

Death in the high mountains: Evidence of interpersonal violence during Late Chalcolithic and Early Bronze Age at Roc de les Orenetes (Eastern Pyrenees, Spain)

OBJECTIVES

To test a hypothesis on interpersonal violence events during the transition between Chalcolithic and Bronze Age in the Eastern Pyrenees, to contextualize it in Western Europe during that period, and to assess if these marks can be differentiated from secondary funerary treatment.

MATERIALS AND METHODS

Metric and non-metric methods were used to estimate the age-at-death and sex of the skeletal remains. Perimortem injuries were observed and analyzed with stereomicroscopy and confocal microscopy.

RESULTS

Among the minimum of 51 individuals documented, at least six people showed evidence of perimortem trauma. All age groups and both sexes are represented in the skeletal sample, but those with violent injuries are predominantly males. Twenty-six bones had 49 injuries, 48 of which involved sharp force trauma on postcranial elements, and one example of blunt force trauma on a cranium. The wounds were mostly located on the upper extremities and ribs, anterior and posterior. Several antemortem lesions were also documented in the assemblage.

DISCUSSION

The perimortem lesions, together with direct dating, suggest that more than one episode of interpersonal violence took place between the Late Chalcolithic and the Early Bronze Age in northeastern Spain. The features of the sharp force trauma indicate that different weapons were used, including sharp metal objects and lithic projectiles. The Roc de les Orenetes assemblage represents a scenario of recurrent lethal confrontation in a high mountain geographic context, representing the evidence of inferred interpersonal violence located at the highest altitude settings in the Pyrenees, at 1836 meters above sea level.

A cranial injury from the earliest Gravettian at the Cro-Magnon rock shelter (Vézère Valley, Dordogne, southwest France)

Discovered over 150 years ago, the early Upper Paleolithic human remains from the Cro-Magnon rock shelter have an iconic status, but because of skeletal commingling after discovery, their bio-profiles remain incomplete and contentious. The defect on the frontal bone of the cranium known as Cro-Magnon 2 has been interpreted as both an antemortem injury and a postmortem (i.e., taphonomic) artifact previously. This contribution considers the cranium in order to clarify the status of the defect on the frontal bone and to situate these remains among others of Pleistocene date with similar types of lesions. The diagnostic criteria used to assess the cranium are drawn from recent publications of actualistic experimental studies of cranial trauma and from those associated with cranial trauma due to violence in forensic anthropological and bioarchaeological contexts. The appearance of the defect and comparison with more recent documented cases from the preantibiotic era suggest that the defect is a result of antemortem trauma with survival for a short period. The location of the lesion on the cranium provides growing evidence for interpersonal aggression in these early modern human groups, and the place of burial also provides insight into related mortuary behavior.

Conflict, violence, and warfare among early farmers in Northwestern Europe

Bioarchaeological evidence of interpersonal violence and early warfare presents important insights into conflict in past societies. This evidence is critical for understanding the motivations for violence and its effects on opposing and competing individuals and groups across time and space. Selecting the Neolithic of northwestern Europe as an area for study, the present paper examines the variation and societal context for the violence recorded in the human skeletal remains from this region as one of the most important elements of human welfare. Compiling data from various sources, it becomes apparent that violence was endemic in Neolithic Europe, sometimes reaching levels of intergroup hostilities that ended in the utter destruction of entire communities. While the precise comparative quantification of healed and unhealed trauma remains a fundamental problem, patterns emerge that see conflict likely fostered by increasing competition between settled and growing communities, e.g., for access to arable land for food production. The further development of contextual information is paramount in order to address hypotheses on the motivations, origins, and evolution of violence as based on the study of human remains, the most direct indicator for actual small- and large-scale violence.

Twenty-first century bioarchaeology: Taking stock and moving forward

This article presents outcomes from a Workshop entitled "Bioarchaeology: Taking Stock and Moving Forward," which was held at Arizona State University (ASU) on March 6-8, 2020. Funded by the National Science Foundation (NSF), the School of Human Evolution and Social Change (ASU), and the Center for Bioarchaeological Research (CBR, ASU), the Workshop's overall goal was to explore reasons why research proposals submitted by bioarchaeologists, both graduate students and established scholars, fared disproportionately poorly within recent NSF Anthropology Program competitions and to offer advice for increasing success. Therefore, this Workshop comprised 43 international scholars and four advanced graduate students with a history of successful grant acquisition, primarily from the United States. Ultimately, we focused on two related aims: (1) best practices for improving research designs and training and (2) evaluating topics of contemporary significance that reverberate through history and beyond as promising trajectories for bioarchaeological research. Among the former were contextual grounding, research question/hypothesis generation, statistical procedures appropriate for small samples and mixed qualitative/quantitative data, the salience of Bayesian methods, and training program content. Topical foci included ethics, social inequality, identity (including intersectionality), climate change, migration, violence, epidemic disease, adaptability/plasticity, the osteological paradox, and the developmental origins of health and disease. Given the profound changes required globally to address decolonization in the 21st century, this concern also entered many formal and informal discussions.

Is History the Same as Evolution? No. Is it Independent of Evolution? Certainly Not

History is full of violence and oppression within and between groups, and although group conflicts enhance within-group cooperation (mediated by oxytocin, which promotes parochial altruism) the hierarchy within groups ensures that spoils accrue very unevenly. Darwin suggested, and we now know, that sexual selection is as powerful as selection by mortality, and the main purpose of survival is reproduction. Male reproductive skew is greater than that among females in all societies, but the difference became much greater after the hunting-gathering era, and the rise of so-called "civilization" was everywhere a process of predatory expansion, producing kingdoms and empires where top males achieved astounding heights of reproductive success. This was shown by historical and ethnographic data now strongly confirmed by genomic science. Psychological research confirms that group identity, out-group stigmatization, leadership characterized by charisma, the will to power, narcissism, sociopathy, and cruelty, and followership characterized by hypnotic obedience, loss of individuality, and cruelty are integral parts of human nature. We can thank at least ten or twelve millennia of microevolutionary processes such as those described above, all more prominent in males than females. Followers in wars have faced a difficult risk-benefit analysis, but if they survived and won they too could increase their reproductive success through the rape and other sexual exploitation that have accompanied almost all wars. For modern leaders, social monogamy and contraception have separated autocracy from reproductive success, but only partly, and current worldwide autocratic trends still depend on the evolved will to power, obedience, and cruelty.

Human Self-Domestication and the Evolution of Pragmatics

As proposed for the emergence of modern languages, we argue that modern uses of languages (pragmatics) also evolved gradually in our species under the effects of human self-domestication, with three key aspects involved in a complex feedback loop: (a) a reduction in reactive aggression, (b) the sophistication of language structure (with emerging grammars initially facilitating the transition from physical aggression to verbal aggression); and (c) the potentiation of pragmatic principles governing conversation, including, but not limited to, turn-taking and inferential abilities. Our core hypothesis is that the reduction in reactive aggression, one of the key factors in self-domestication processes, enabled us to fully exploit our cognitive and interactional potential as applied to linguistic exchanges, and ultimately to evolve a specific form of communication governed by persuasive reciprocity-a trait of human conversation characterized by both competition and cooperation. In turn, both early crude forms of language, well suited for verbal aggression/insult, and later more sophisticated forms of language, well suited for persuasive reciprocity, significantly contributed to the resolution and reduction of (physical) aggression, thus having a return effect on the self-domestication processes. Supporting evidence for our proposal, as well as grounds for further testing, comes mainly from the consideration of cognitive disorders, which typically simultaneously present abnormal features of self-domestication (including aggressive behavior) and problems with pragmatics and social functioning. While various approaches to language evolution typically reduce it to a single factor, our approach considers language evolution as a multifactorial process, with each player acting upon the other, engaging in an intense mutually reinforcing feedback loop. Moreover, we see language evolution as a gradual process, continuous with the pre-linguistic cognitive abilities, which were engaged in a positive feedback loop with linguistic innovations, and where gene-culture co-evolution and cultural niche construction were the main driving forces.

New insights on interpersonal violence in the Late Pleistocene based on the Nile valley cemetery of Jebel Sahaba

The remains of 61 individuals buried in the cemetery of Jebel Sahaba (site 117) offer unique and substantial evidence to the emergence of violence in the Nile Valley at the end of the Late Pleistocene. Excavated and assessed in the 1960s, some of the original findings and interpretations are disputed. A full reanalysis of the timing, nature and extent of the violence was conducted through the microscopic characterization of the nature of each osseous lesion, and the reassessment of the archaeological data. Over 100 previously undocumented healed and unhealed lesions were identified on both new and/or previously identified victims, including several embedded lithic artefacts. Most trauma appears to be the result of projectile weapons and new analyses confirm for the first time the repetitive nature of the interpersonal acts of violence. Indeed, a quarter of the skeletons with lesions exhibit both healed and unhealed trauma. We dismiss the hypothesis that Jebel Sahaba reflects a single warfare event, with the new data supporting sporadic and recurrent episodes of inter-personal violence, probably triggered by major climatic and environmental changes. At least 13.4 ka old, Jebel Sahaba is one of the earliest sites displaying interpersonal violence in the world.

Neanderthals and Homo sapiens had similar auditory and speech capacities

The study of audition in fossil hominins is of great interest given its relationship with intraspecific vocal communication. While the auditory capacities have been studied in early hominins and in the Middle Pleistocene Sima de los Huesos hominins, less is known about the hearing abilities of the Neanderthals. Here, we provide a detailed approach to their auditory capacities. Relying on computerized tomography scans and a comprehensive model from the field of auditory bioengineering, we have established sound power transmission through the outer and middle ear and calculated the occupied bandwidth in Neanderthals. The occupied bandwidth is directly related to the efficiency of the vocal communication system of a species. Our results show that the occupied bandwidth of Neanderthals was greater than the Sima de los Huesos hominins and similar to extant humans, implying that Neanderthals evolved the auditory capacities to support a vocal communication system as efficient as modern human speech.

Was it an axe or an adze? A cranial trauma case study from the Late Neolithic - Chalcolithic site of Cova Foradada (Calafell, Spain)

OBJECTIVE

To reconstruct the etiology of a perimortem injury observed on a Neolithic - Chalcolithic cranium (5060 - 4400 yrs cal. BP).

MATERIALS

A cranium of an old adult male individual belonging to a collective burial from Cova Foradada site (Calafell, Tarragona, Spain).

METHODS

The cranium was analyzed macroscopically and microscopically using micro-CT scan.

RESULTS

The fracture on the right parietal bone presents characteristics of perimortem trauma. The morphology of the point of impact allows for the interpretation of this fracture as a result of impact by an object with a straight and sharp edge. In addition, the same cranium presents two healed antemortem injuries.

CONCLUSIONS

The object that most likely caused the cranial fracture was a stone adze. The blow occurred from behind the individual, possibly by a right-handed attacker.

SIGNIFICANCE

The potential to link cranial fractures with specific tools increases our understanding of interpersonal violence during the Neolithic.

LIMITATIONS

It is not possible to infer if this cranial injury was related to a large-scale intergroup confrontation or an intragroup violent event.

SUGGESTIONS FOR FURTHER RESEARCH

To investigate additional similar sites in the northeastern Iberian Peninsula to better characterize the fracture pattern caused by stone axes and adzes as well as other objects used as weapons during the Neolithic - Chalcolithic ages.

Pluridisciplinary evidence for burial for the La Ferrassie 8 Neandertal child

The origin of funerary practices has important implications for the emergence of so-called modern cognitive capacities and behaviour. We provide new multidisciplinary information on the archaeological context of the La Ferrassie 8 Neandertal skeleton (grand abri of La Ferrassie, Dordogne, France), including geochronological data -¹⁴C and OSL-, ZooMS and ancient DNA data, geological and stratigraphic information from the surrounding context, complete taphonomic study of the skeleton and associated remains, spatial information from the 1968-1973 excavations, and new (2014) fieldwork data. Our results show that a pit was dug in a sterile sediment layer and the corpse of a two-year-old child was laid there. A hominin bone from this context, identified through Zooarchaeology by Mass Spectrometry (ZooMS) and associated with Neandertal based on its mitochondrial DNA, yielded a direct ¹⁴C age of 41.7-40.8 ka cal BP (95%), younger than the ¹⁴C dates of the overlying archaeopaleontological layers and the OSL age of the surrounding sediment. This age makes the bone one of the most recent directly dated Neandertals. It is consistent with the age range for the Châtelperronian in the site and in this region and represents the third association of Neandertal taxa to Initial Upper Palaeolithic lithic technocomplex in Western Europe. A detailed multidisciplinary approach, as presented here, is essential to advance understanding of Neandertal behavior, including funerary practices.

Prevalence of cranial trauma in Eurasian Upper Paleolithic humans

OBJECTIVES

This study characterizes patterns of cranial trauma prevalence in a large sample of Upper Paleolithic (UP) fossil specimens (40,000-10,000 BP).

MATERIALS AND METHODS

Our sample comprised 234 individual crania (specimens), representing 1,285 cranial bones (skeletal elements), from 101 Eurasian UP sites. We used generalized linear mixed models (GLMMs) to assess trauma prevalence in relation to age-at-death, sex, anatomical distribution, and between pre- and post-Last Glacial Maximum (LGM) samples, while accounting for skeletal preservation.

RESULTS

Models predicted a mean cranial trauma prevalence of 0.07 (95% CI 0.003-0.19) at the level of skeletal elements, and of 0.26 (95% CI 0.08-0.48) at the level of specimens, each when 76-100% complete. Trauma prevalence increased with skeletal preservation. Across specimen and skeletal element datasets, trauma prevalence tended to be higher for males, and was consistently higher in the old age group. We found no time-specific trauma prevalence patterns for the two sexes or age cohorts when comparing samples from before and after the LGM. Samples showed higher trauma prevalence in the vault than in the face, with vault remains being affected predominantly in males.

DISCUSSION

Cranial trauma prevalence in UP humans falls within the variation described for Mesolithic and Neolithic samples. According to our current dataset, UP males and females were exposed to slightly different injury risks and trauma distributions, potentially due to different activities or behaviors, yet both sexes exhibit more trauma among the old. Environmental stressors associated with climatic changes of the LGM are not reflected in cranial trauma prevalence. To analyze trauma in incomplete skeletal remains we propose GLMMs as an informative alternative to crude frequency calculations.

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.

Ectopic maxillary third molar in Early Pleistocene Homo antecessor from Atapuerca-Gran Dolina site (Burgos, Spain)

OBJECTIVES

Here we describe the case of an ectopic maxillary third molar (M³ ), preventing the eruption of the M² , in the individual H3 of the hominin hypodigm of level TD6.2 of the Early Pleistocene site of Gran Dolina (Sierra de Atapuerca, Spain).

MATERIALS AND METHODS

The fossil remains from the TD6.2 level of the Gran Dolina site (about 170 specimens) are assigned to Homo antecessor. Different geochronological methods place these hominins in the oxygen isotopic stage 21, between 0.8 and 0.85 million years ago (Ma). The immature individual H3 is represented by an almost complete midface (ATD6-69), preserving various teeth in situ. We used high-resolution microtomograhy (mCT) to investigate the abnormal position of the left M³ , virtually reconstruct M² , and M³ as well as assessing the development stage of these. Finally, we compare this case with extinct and extant populations.

RESULTS

Based on the identified signs, we suggest that individual H3 suffered from a unilateral impaction of the M² as a result of the ectopic position of the developing M³ .

DISCUSSION

We conclude that the most likely etiology for the ectopic position of the M³ is the lack of space in the maxilla. We discuss possible contributing factors, such as morphometric aspects of the maxilla and the early mineralization of the M³ , to support the M² impaction. Finally, due to the early age at death of this individual we did not identify any secondary lesion associated with the M² impaction.

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.

A revision of the conductive hearing loss in Cranium 4 from the Middle Pleistocene site of Sima de los Huesos (Burgos, Spain)

Pathological conditions have been previously documented in the Middle Pleistocene Sima de los Huesos hominins from northern Spain, and several of these have clear behavioral implications. Within this fossil assemblage, Cranium 4 shows bilateral external auditory exostoses which have been preliminarily interpreted as causing a significant hearing loss in this individual. If confirmed, this would be the oldest recorded case of deafness in human history and could have important implications for the antiquity of this condition, as well as social interactions. To further investigate this case, the current study presents 3D reconstructions of the entire outer and middle ear, based on computed tomography scans of both temporal bones in Cranium 4. We established the degree of stenosis in both external auditory canals, showing that in both cases the degree of stenosis is less than 52% of the original cross-sectional area of each canal. Based on clinical studies in living humans, the buildup of wax due to the degree of stenosis in Cranium 4 is unlikely to have caused frequent external ear infections. In addition, we estimated the pattern of sound power transmission up to 5 kHz in both ears relying on a comprehensive model developed in the bioengineering literature and which has been applied previously to the Sima de los Huesos hominins. The model was modified to account for the peculiar shape of the pathological external ear canals in Cranium 4. The results show that this pathology had little to no influence on the sound power transmission in this individual. Thus, we conclude that the exostoses present in both ears of Cranium 4 did not significantly affect their hearing.

State of the art forensic techniques reveal evidence of interpersonal violence ca. 30,000 years ago

The Cioclovina (Romania) calvaria, dated to ca. 33 cal ka BP and thought to be associated with the Aurignacian lithic industry, is one of the few relatively well preserved representatives of the earliest modern Europeans. Two large fractures on this specimen have been described as taphonomic modifications. Here we used gross and virtual forensic criteria and experimental simulations on synthetic bone models, to investigate their nature. Both forensic trauma pattern analysis and experimental models exclude a postmortem origin for the Cioclovina fractures. Rather, they indicate two incidents of blunt force trauma, the second clearly inflicted with a club-like object. The magnitude and extent of the lesions and the lack of signs of healing indicate a fatal injury. The Upper Paleolithic period is noted for intensified technological innovation, increased symbolic behavior, and cultural complexity. We show that the behavioural repertoire of the earliest modern Europeans also comprised violent inter-personal interactions and murder.

Violence in the workplace: some critical issues looking at the health sector

BACKGROUND

The literature on occupational violence and even more the literature on violence against nurses in health settings have evidenced inconsistencies regarding how workplace violence has been conceptualized.

PURPOSE

To review and discuss some inconsistencies regarding how workplace violence against nurses in health settings has been conceptualized paying special attention to the challenges posed to the health of nurses stemming from patients, visitors or co-workers.

METHOD

Review of data of the European Working Conditions Surveys, and National Surveys on Working Conditions in Spain.

DISCUSSION

It is necessary to overcome these conceptual inconsistencies on violence in order to carry out intervention programmes based on solid theoretical grounds.

CONCLUSIONS

Violence against nurses takes place within an organisational climate defined by role relationships. The organizational climate can either reduce the likelihood of violence or, on the contrary, instigate violent behaviors.

The emergence of human warfare: Current perspectives

The origins of warfare have long been of interest for researchers across disciplines. Did our earliest ancestors engage in forms of organized violence that are appropriately viewed as approximations, forms of, or analogs for more recent forms of warfare? Assessed in this article are contrasting views that see warfare as being either a product of more recent human societies or a phenomenon with a much deeper chronology. The article provides an overview of current debates, theories, and methodological approaches, citing literature and data from archaeological, ethnographic, genetic, primatological, and paleoanthropological studies. Synthetic anthropological treatments are needed, especially in efforts to inform debates among nonacademic audiences, because the discipline's approaches are ideally suited to study the origins of warfare. Emphasized is the need to consider possible forms of violence and intergroup aggression within Pleistocene contexts, despite the methodological challenges associated with fragmentary, equivocal, or scarce data. Finally, the review concludes with an argument about the implications of the currently available data. We propose that socially cooperative violence, or "emergent warfare," became possible with the onset of symbolic thought and complex cognition. Viewing emergent warfare as a byproduct of the human capacity for symbolic thought explains how the same capacities for communication and sociality allowed for elaborate peacemaking, conflict resolution, and avoidance. Cultural institutions around war and peace are both made possible by these changes. Accordingly, we suggest that studies on warfare's origins should be tied to research on the advent of cooperation, sociality, and communication.

Human niche, human behaviour, human nature

The concept of a 'human nature' or 'human natures' retains a central role in theorizing about the human experience. In Homo sapiens it is clear that we have a suite of capacities generated via our evolutionary past, and present, and a flexible capacity to create and sustain particular kinds of cultures and to be shaped by them. Regardless of whether we label these capacities 'human natures' or not, humans occupy a distinctive niche and an evolutionary approach to examining it is critical. At present we are faced with a few different narratives as to exactly what such an evolutionary approach entails. There is a need for a robust and dynamic theoretical toolkit in order to develop a richer, and more nuanced, understanding of the cognitively sophisticated genus Homo and the diverse sorts of niches humans constructed and occupied across the Pleistocene, Holocene, and into the Anthropocene. Here I review current evolutionary approaches to 'human nature', arguing that we benefit from re-framing our investigations via the concept of the human niche and in the context of the extended evolutionary synthesis (EES). While not a replacement of standard evolutionary approaches, this is an expansion and enhancement of our toolkit. I offer brief examples from human evolution in support of these assertions.

Large-scale effects of migration and conflict in pre-agricultural groups: Insights from a dynamic model

The debate on the causes of conflict in human societies has deep roots. In particular, the extent of conflict in hunter-gatherer groups remains unclear. Some authors suggest that large-scale violence only arose with the spreading of agriculture and the building of complex societies. To shed light on this issue, we developed a model based on operatorial techniques simulating population-resource dynamics within a two-dimensional lattice, with humans and natural resources interacting in each cell of the lattice. The model outcomes under different conditions were compared with recently available demographic data for prehistoric South America. Only under conditions that include migration among cells and conflict was the model able to consistently reproduce the empirical data at a continental scale. We argue that the interplay between resource competition, migration, and conflict drove the population dynamics of South America after the colonization phase and before the introduction of agriculture. The relation between population and resources indeed emerged as a key factor leading to migration and conflict once the carrying capacity of the environment has been reached.

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

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

Modern humans, or Homo sapiens, are now the only living species in their genus. But as recently as 20,000 years ago there were other species that belonged to the genus Homo. Together with modern humans, these extinct human species, our immediate ancestors and their close relatives are collectively referred to as ‘hominins’.

Now, Dirks et al. describe an unusual collection of hominin fossils that were found within the Dinaledi Chamber in the Rising Star cave system in South Africa. The fossils all belong to a newly discovered hominin species called Homo naledi, which is described in a related study by Berger et al. The unearthed fossils are the largest collection of hominin fossils from a single species ever to be discovered in Africa, and include the remains of at least 15 individuals and multiple examples of most of the bones in the skeleton.

Dirks et al. explain that the assemblage from the Dinaledi Chamber is unusual because of the large number of fossils discovered so close together in a single chamber deep within the cave system. It is also unusual that no other large animal remains were found in the chamber, and that the bodies had not been damaged by scavengers or predators. The fossils were excavated from soft clay-rich sediments that had accumulated in the chamber over time; it also appears that the bodies were intact when they arrived in the chamber, and then started to decompose.

Dirks et al. discuss a number of explanations as to how the remains came to rest in the Dinaledi Chamber, which range from whether Homo naledi lived in the caves to whether they were brought in by predators. Most of the evidence obtained so far is largely consistent with these bodies being deliberately disposed of in this single location by the same extinct hominin species. However, a number of other explanations cannot be completely ruled out and further investigation is now needed to uncover the series of events that resulted in this unique collection of hominin fossils.

DOI:http://dx.doi.org/10.7554/eLife.09561.002

Diametrical diseases reflect evolutionary-genetic tradeoffs: Evidence from psychiatry, neurology, rheumatology, oncology and immunology

Tradeoffs centrally mediate the expression of human adaptations. We propose that tradeoffs also influence the prevalence and forms of human maladaptation manifest in disease. By this logic, increased risk for one set of diseases commonly engenders decreased risk for another, diametric, set of diseases. We describe evidence for such diametric sets of diseases from epidemiological, genetic and molecular studies in four clinical domains: (i) psychiatry (autism vs psychotic-affective conditions), (ii) rheumatology (osteoarthritis vs osteoporosis), (iii) oncology and neurology (cancer vs neurodegenerative disorders) and (iv) immunology (autoimmunity vs infectious disease). Diametric disorders are important to recognize because genotypes or environmental factors that increase risk for one set of disorders protect from opposite disorders, thereby providing novel and direct insights into disease causes, prevention and therapy. Ascertaining the mechanisms that underlie disease-related tradeoffs should also indicate means of circumventing or alleviating them, and thus reducing the incidence and impacts of human disease in a more general way.

The massacre mass grave of Schöneck-Kilianstädten reveals new insights into collective violence in Early Neolithic Central Europe

Conflict and warfare are central but also disputed themes in discussions about the European Neolithic. Although a few recent population studies provide broad overviews, only a very limited number of currently known key sites provide precise insights into moments of extreme and mass violence and their impact on Neolithic societies. The massacre sites of Talheim, Germany, and Asparn/Schletz, Austria, have long been the focal points around which hypotheses concerning a final lethal crisis of the first Central European farmers of the Early Neolithic Linearbandkeramik Culture (LBK) have concentrated. With the recently examined LBK mass grave site of Schöneck-Kilianstädten, Germany, we present new conclusive and indisputable evidence for another massacre, adding new data to the discussion of LBK violence patterns. At least 26 individuals were violently killed by blunt force and arrow injuries before being deposited in a commingled mass grave. Although the absence and possible abduction of younger females has been suggested for other sites previously, a new violence-related pattern was identified here: the intentional and systematic breaking of lower limbs. The abundance of the identified perimortem fractures clearly indicates torture and/or mutilation of the victims. The new evidence presented here for unequivocal lethal violence on a large scale is put into perspective for the Early Neolithic of Central Europe and, in conjunction with previous results, indicates that massacres of entire communities were not isolated occurrences but rather were frequent features of the last phases of the LBK.