Exploring variability in lithic armature discard in the archaeological record.

The invention of projectile technology had important ramifications for hominin evolution. However, the number of stone points that could have been used as projectiles fluctuates in archaeological assemblages, making it difficult to define when projectile technology was first widely adopted and how its usage changed over time. Here we use an agent-based model to simulate a hunter-gatherer foraging system where armatures are dropped according to their usage. We explore the impact of interactions between human behaviors and the environmental constraints of a data-informed landscape on the distribution and number of lithic armatures found in archaeological assemblages. We ran 2400 simulations modeling different population sizes, rates of hunting with projectiles, and tool curation levels. For each simulation, we recorded the location of dropped armatures and calculated the number and percentage of used armatures that were discarded at habitation camps vs. lost during hunting. We used linear regression to identify the demographic, behavioral, and environmental factor(s) that best explained changes in these numbers and percentages. The model results show that in a well-controlled environment, most armatures used as projectile weapons are lost or discarded at hunting sites; only ∼4.5% of used armatures (or ∼2 armatures per year of simulation) are discarded in habitation camps where they would likely be excavated. These findings suggest that even rare hafted armatures found in the Early and Middle Stone Age could indicate a well-established use of such tools. Our model shows that interactions between reoccupation of archaeological sites, population size, rate of hunting with projectile weapons, and tool curation levels strongly influence the count of lithic armatures found in archaeological assemblages. Therefore, we argue that fluctuations in the counts of armatures documented at archaeological sites should be evaluated within their demographic and environmental contexts to better understand if they reflect spatiotemporal changes in hunting behavior.

Human remains from Arma di Nasino (Liguria) provide novel insights into the paleoecology of early Holocene foragers in northwestern Italy.

We report the discovery and analysis of new Mesolithic human remains-dated to ca. 10,200-9000 cal. BP-from Arma di Nasino in Liguria, northwestern Italy, an area rich in Upper Paleolithic and Neolithic attestations, but for which little information on Early Holocene occupation was available. The multi-proxy isotopic profile of the two individuals reveals that-despite the proximity of the site to the Mediterranean seashore and the use of shellfish as decorative elements in burials-the ecology of these foragers was based on the exploitation of high-altitude resources, presumably in the nearby western Alps. This constitutes the first direct evidence in northwestern Italy of a significant ecological shift towards higher altitudes following deglaciation, especially when compared to isotopic data of the Late Pleistocene hunter-gatherers from the nearby site of Arene Candide Cave, who exploited terrestrial resources nearer to the coast and at lower altitudes. While the biochemistry of Nasino's skeletal assemblage revealed new details on Early Holocene lifeways in the area, the osteobiography of one individual offers glimpses into the life experience of a specific female forager, depicting a scenario of early skeletal trauma, developmental disturbances, long-term impairments, and resilience amongst the last European hunter-gatherers.

Understanding hunter-gatherer cultural evolution needs network thinking.

Hunter-gatherers past and present live in complex societies, and the structure of these can be assessed using social networks. We outline how the integration of new evidence from cultural evolution experiments, computer simulations, ethnography, and archaeology open new research horizons to understand the role of social networks in cultural evolution.

An infant burial from Arma Veirana in northwestern Italy provides insights into funerary practices and female personhood in early Mesolithic Europe.

The evolution and development of human mortuary behaviors is of enormous cultural significance. Here we report a richly-decorated young infant burial (AVH-1) from Arma Veirana (Liguria, northwestern Italy) that is directly dated to 10,211-9910 cal BP (95.4% probability), placing it within the early Holocene and therefore attributable to the early Mesolithic, a cultural period from which well-documented burials are exceedingly rare. Virtual dental histology, proteomics, and aDNA indicate that the infant was a 40-50 days old female. Associated artifacts indicate significant material and emotional investment in the child's interment. The detailed biological profile of AVH-1 establishes the child as the earliest European near-neonate documented to be female. The Arma Veirana burial thus provides insight into sex/gender-based social status, funerary treatment, and the attribution of personhood to the youngest individuals among prehistoric hunter-gatherer groups and adds substantially to the scant data on mortuary practices from an important period in prehistory shortly following the end of the last Ice Age.