Human Descent
The evolution of altruism through war is highly sensitive to population structure and to civilian and fighter mortality
Mark Dyble
Proceedings of the National Academy of Sciences, 16 March 2021
Abstract:
The importance of warfare in the evolution of human social behavior remains highly debated. One hypothesis is that intense warfare between groups favored altruism within groups, a hypothesis given some support by computational modeling and, in particular, the work of Choi and Bowles [J.-K. Choi, S. Bowles, Science 318, 636–640 (2007)]. The results of computational models are, however, sensitive to chosen parameter values and a deeper assessment of the plausibility of the parochial altruism hypothesis requires exploring this model in more detail. Here, I use a recently developed method to reexamine Choi and Bowles’ model under a much broader range of conditions to those used in the original paper. Although the evolution of altruism is robust to perturbations in most of the default parameters, it is highly sensitive to group size and migration and to the lethality of war. The results show that the degree of genetic differentiation between groups (FST) produced by Choi and Bowles’ original model is much greater than empirical estimates of FST between hunter-gatherer groups. When FST in the model is close to empirically observed values, altruism does not evolve. These results cast doubt on the importance of war in the evolution of human sociality.
Genome-wide analysis of nearly all the victims of a 6200 year old massacre
Mario Novak et al.
PLoS ONE, March 2021
Abstract:
Paleogenomic and bioanthropological studies of ancient massacres have highlighted sites where the victims were male and plausibly died all in battle, or were executed members of the same family as might be expected from a killing intentionally directed at subsets of a community, or where the massacred individuals were plausibly members of a migrant community in conflict with previously established groups, or where there was evidence that the killing was part of a religious ritual. Here we provide evidence of killing on a massive scale in prehistory that was not directed to a specific family, based on genome-wide ancient DNA for 38 of the 41 documented victims of a 6,200 year old massacre in Potočani, Croatia and combining our results with bioanthropological data. We highlight three results: (i) the majority of individuals were unrelated and instead were a sample of what was clearly a large farming population, (ii) the ancestry of the individuals was homogenous which makes it unlikely that the massacre was linked to the arrival of new genetic ancestry, and (iii) there were approximately equal numbers of males and females. Combined with the bioanthropological evidence that the victims were of a wide range of ages, these results show that large-scale indiscriminate killing is a horror that is not just a feature of the modern and historic periods, but was also a significant process in pre-state societies.
Ritual responses to catastrophic volcanism in Viking Age Iceland: Reconsidering Surtshellir Cave through Bayesian analyses of AMS dates, tephrochronology, and texts
Kevin Smith, Guðmundur Ólafsson & Albína Hulda Pálsdóttir
Journal of Archaeological Science, February 2021
Abstract:
Surtshellir, a 1600-m-long lava cave in the interior of Iceland, contains a unique Viking Age archaeological site located nearly 300 m from its entrance and more than 10 m below the surface of the Hallmundarhraun lava field. Since the 1750s, the site has been interpreted as an outlaw shelter, yet in the 12th-13th centuries it was associated with actions directed towards an elemental being – Surtr – for whom the site was named and who, according to medieval Icelandic accounts of Viking Age mythology, was present at the world's creation and would destroy it after the battle of Ragnarök. Archaeological fieldwork inside Surtshellir in 2001, 2012, and 2013 produced 20 new AMS dates that, combined with three earlier radiocarbon and tephrochronological dates, provide the basis for Bayesian analyses which suggest (1) that the cave formed in the first major volcanic eruption directly witnessed by northern Europeans since the Late Pleistocene; (2) that this took place shortly after the Norse colonization of Iceland began; (3) that people entered the cave soon afterwards; (4) that for 80–120 years they deposited the fragmented bones of slaughtered domestic animals in piles stretching 120 m through the cave's “dark zone”, burning others at high temperatures in a dry-stone structure built deep inside a raised side passage; and (5) that these activities ended shortly after Iceland's conversion to Christianity. Surtshellir provides important new insights into Viking Age ritual practice, Iceland's settlement and conversion, and the cultural responses of Iceland's newly arrived settlers to the existential challenges posed by previously unimagined catastrophic volcanism.
Management systems of adhesive materials throughout the Neolithic in the North-West Mediterranean
Maxime Rageot et al.
Journal of Archaeological Science, February 2021
Abstract:
Plant resins, tars and organic fossil substances provide valuable insights into the ecological, environmental and cultural contexts of ancient societies. Their study offers evidence of past know-how, production systems, socio-economic networks and mobility. In this paper, we present new data from 16 sites located in the North-West Mediterranean that provide new insights into the exploitation of these substances for their adhesive and hydrophobic properties throughout the Neolithic (6000-2500 cal BCE). The substances investigated are discussed in the light of their molecular composition, their uses and manufacturing processes. Spatial analyses were also performed to elucidate raw material procurement strategies. This study considerably increases the body of data available from the Mediterranean and tells a diachronic story of adhesive production and use throughout the Neolithic, highlighting the variability and complexity of production systems and supply networks at different spatial scales. While most adhesive and hydrophobic substances were probably collected locally, birch bark tar was very likely transported across long distances to reach Mediterranean coastal sites. Birch bark tar exploitation intensified in South-Eastern France during the Middle Neolithic, while the Late Neolithic is characterised by a diversification of the substances employed and their range of uses: bitumen, birch bark tar (pure or mixed with Pinaceae resin, beeswax and possibly fat/oil) were important materials that were used for a variety of purposes. Pure Pinaceae exudates were exclusively employed for waterproofing pottery. We also highlight the standardisation of birch bark tar production for adhesive manufacture observed in Provence during the first part of the 4th millennium cal. BCE.
24.0 kyr cal BP stone artefact from Vale da Pedra Furada, Piauí, Brazil: Techno-functional analysis
Eric Boëda et al.
PLoS ONE, March 2021
Abstract:
Current archaeological paradigm proposes that the first peopling of the Americas does not exceed the Last Glacial Maximum period. In this context, the acceptance of the anthropogenic character of the earliest stone artefacts generally rests on the presence of projectile points considered no more as typocentric but as typognomonic, since it allows, by itself, to certify the human character of the other associated artefacts. In other words, without this presence, nothing is certain. Archaeological research at Piauí (Brazil) attests to a Pleistocene human presence between 41 and 14 cal kyr BP, without any record of lithic projectile points. Here, we report the discovery and interpretation of an unusual stone artefact in the Vale da Pedra Furada site, in a context dating back to 24 cal kyr BP. The knapping stigmata and macroscopic use-wear traces reveal a conception centred on the configuration of double bevels and the production in the same specimen of at least two successive artefacts with probably different functions. This piece unambiguously presents an anthropic character and reveals a technical novelty during the Pleistocene occupation of South America.
Reevaluating the timing of Neanderthal disappearance in Northwest Europe
Thibaut Devièse et al.
Proceedings of the National Academy of Sciences, 23 March 2021
Abstract:
Elucidating when Neanderthal populations disappeared from Eurasia is a key question in paleoanthropology, and Belgium is one of the key regions for studying the Middle to Upper Paleolithic transition. Previous radiocarbon dating placed the Spy Neanderthals among the latest surviving Neanderthals in Northwest Europe with reported dates as young as 23,880 ± 240 B.P. (OxA-8912). Questions were raised, however, regarding the reliability of these dates. Soil contamination and carbon-based conservation products are known to cause problems during the radiocarbon dating of bulk collagen samples. Employing a compound-specific approach that is today the most efficient in removing contamination and ancient genomic analysis, we demonstrate here that previous dates produced on Neanderthal specimens from Spy were inaccurately young by up to 10,000 y due to the presence of unremoved contamination. Our compound-specific radiocarbon dates on the Neanderthals from Spy and those from Engis and Fonds-de-Forêt demonstrate that they disappeared from Northwest Europe at 44,200 to 40,600 cal B.P. (at 95.4% probability), much earlier than previously suggested. Our data contribute significantly to refining models for Neanderthal disappearance in Europe and, more broadly, show that chronometric models regarding the appearance or disappearance of animal or hominin groups should be based only on radiocarbon dates obtained using robust pretreatment methods.