U-Th dating of carbonate crusts reveals Neandertal origin of Iberian cave art

Using drawings and deep neural networks to characterize the building blocks of human visual similarity

Early in life and without special training, human beings discern resemblance between abstract visual stimuli, such as drawings, and the real-world objects they represent. We used this capacity for visual abstraction as a tool for evaluating deep neural networks (DNNs) as models of human visual perception. Contrasting five contemporary DNNs, we evaluated how well each explains human similarity judgments among line drawings of recognizable and novel objects. For object sketches, human judgments were dominated by semantic category information; DNN representations contributed little additional information. In contrast, such features explained significant unique variance perceived similarity of abstract drawings. In both cases, a vision transformer trained to blend representations of images and their natural language descriptions showed the greatest ability to explain human perceptual similarity-an observation consistent with contemporary views of semantic representation and processing in the human mind and brain. Together, the results suggest that the building blocks of visual similarity may arise within systems that learn to use visual information, not for specific classification, but in service of generating semantic representations of objects.

A global cross-cultural analysis of string figures reveals evidence of deep transmission and innovation

Few cultural practices beyond language are as widespread as string figure games. Their global distribution and potential to yield insights into cultural transmission and cognition have long been noted. Yet, it remains unknown how or when this behaviour originated and to what extent shared motifs are signals of repeated innovations or deep cultural transmission. Here, we combined a global cross-cultural inventory of string figures with a novel methodology based on knot theory, which enables the unequivocal numerical coding of string figures. We performed a computational analysis of a sample of 826 figures from 92 societies around the world. Across these societies, we found 83 recurring string figure designs, some of which are regionally restricted while others display a global distribution. The cognitively opaque nature of string figure designs and their clear geographic distribution reveal processes of cultural transmission, innovation, and convergent evolution. Most strikingly, the global distribution of some figures raises the possibility of shared ancient origins.

Unraveling mechanisms of human brain evolution

Evolutionary changes in human brain structure and function have enabled our specialized cognitive abilities. How these changes have come about genetically and functionally has remained an open question. However, new methods are providing a wealth of information about the genetic, epigenetic, and transcriptomic differences that set the human brain apart. Combined with in vitro models that allow access to developing brain tissue and the cells of our closest living relatives, the puzzle pieces are now coming together to yield a much more complete picture of what is actually unique about the human brain. The challenge now will be linking these observations and making the jump from correlation to causation. However, elegant genetic manipulations are now possible and, when combined with model systems such as organoids, will uncover a mechanistic understanding of how evolutionary changes at the genetic level have led to key differences in development and function that enable human cognition.

Study of the Chemical Recovery and Selectivity against U in the Radiochemical Separation of Th with Tri-n-butyl Phosphate by Varying the Proportion of Xylene and HCl Concentration

Thorium is a radionuclide used in various environmental studies such as dating, sediment movement, soil-plant transfer studies, and contamination of waste from the natural fuel cycle. The liquid-liquid extraction method using tri-n-butyl phosphate (TBP) allows for the separation of Th from the accompanying actinides. However, the separation of Th and U present in the same sample is not trivial. This separation is influenced by the starting acid (HCl or HNO3), the concentration of TBP in an organic solvent, and the concentration of the acid used for re-extracting Th, which is typically HCl. Therefore, it is necessary to study these factors to ensure that the method has sufficient chemical yield and selectivity in complex matrices. This study presents a systematic investigation of the aforementioned parameters, making the necessary variations to select an optimal method for the radiochemical separation of Th. The ideal conditions were obtained using 4 M HCl as the acid prior to extraction, a 1:4 solution of TBP in xylene, and 4 M HCl as the re-extracting agent. The accuracy and precision were studied in four intercomparison exercises conducted in quadruplicate, using the parameters Enumbers, RB(%), and RSD(%) for 232Th and 230Th. The sensitivity of the method was experimentally studied and the limit of detection (LoD) was determined according to ISO 11929:2005. Additionally, the linearity of the method showed that the experimental and theoretical activity concentrations of 232Th and 230Th had slopes of 1 with an intercept close to 0.

Narrative cave art in Indonesia by 51,200 years ago

Previous dating research indicated that the Indonesian island of Sulawesi is host to some of the oldest known rock art1-3. That work was based on solution uranium-series (U-series) analysis of calcite deposits overlying rock art in the limestone caves of Maros-Pangkep, South Sulawesi1-3. Here we use a novel application of this approach-laser-ablation U-series imaging-to re-date some of the earliest cave art in this karst area and to determine the age of stylistically similar motifs at other Maros-Pangkep sites. This method provides enhanced spatial accuracy, resulting in older minimum ages for previously dated art. We show that a hunting scene from Leang Bulu' Sipong 4, which was originally dated using the previous approach to a minimum of 43,900 thousand years ago (ka)3, has a minimum age of 50.2 ± 2.2 ka, and so is at least 4,040 years older than thought. Using the imaging approach, we also assign a minimum age of 53.5 ± 2.3 ka to a newly described cave art scene at Leang Karampuang. Painted at least 51,200 years ago, this narrative composition, which depicts human-like figures interacting with a pig, is now the earliest known surviving example of representational art, and visual storytelling, in the world3. Our findings show that figurative portrayals of anthropomorphic figures and animals have a deeper origin in the history of modern human (Homo sapiens) image-making than recognized to date, as does their representation in composed scenes.

Exploring the utility of Geometric Morphometrics to analyse prehistoric hand stencils

Hand stencils are a remarkable graphic expression in Prehistoric rock art, dating back to 42 ka BP. Although these stencils provide direct impressions of the artists' hands, the characterization of their biological profile (i.e., biological sex and age) is very challenging. Previous studies have attempted this analysis with traditional morphometrics (TM), whereas little research has been undertaken using Geometric Morphometrics (GM), a method widely used in other disciplines but only tentatively employed in rock art studies. However, the large variation in relative finger position in archaeological hands poses the question of whether these representations can be examined through GM, or, in contrast, if this creates an unmanageable error in the results. To address this issue, a 2D hand scans sample of 70 living individuals (F = 35; M = 35) has been collected in three standardized positions (n = 210) and digitized with 32 2D conventional landmarks. Results show that the intra-individual distance (mean Procrustes distance between Pos. 1-2 = 0.132; 2-3 = 0.191; 1-3 = 0.292) is larger than the inter-individual distance (mean in 1 = 0.122; 2 = 0.142; 3 = 0.165). Finally, it has been demonstrated that the relative finger positions, as well as the inclusion of all hand parts in the analysis, have an overshadowing effect on other variables potentially involved in the morphometric variability of the hand, such as biological sex.

Punctuated equilibrium at 50: Anything there for evolutionary anthropology? Yes; definitely

The theory of punctuated equilibrium (PE) was developed a little over 50 years ago to explain long-term, large-scale appearance and disappearance of species in the fossil record. A theory designed specifically for that purpose cannot be expected, out of the box, to be directly applicable to biocultural evolution, but in revised form, PE offers a promising approach to incorporating not only a wealth of recent empirical research on genetic, linguistic, and technological evolution but also large databases that document human biological and cultural diversity across time and space. Here we isolate the fundamental components of PE and propose which pieces, when reassembled or renamed, can be highly useful in evolutionary anthropology, especially as humanity faces abrupt ecological challenges on an increasingly larger scale.

Towards correlative archaeology of the human mind

Retracing human cognitive origins started out at the systems level with the top-down interpretation of archaeological records spanning from man-made artifacts to endocasts of ancient skulls. With emerging evolutionary genetics and organoid technologies, it is now possible to deconstruct evolutionary processes on a molecular/cellular level from the bottom-up by functionally testing archaic alleles in experimental models. The current challenge is to complement these approaches with novel strategies that allow a holistic reconstruction of evolutionary patterns across human cognitive domains. We argue that computational neuroarcheology can provide such a critical mesoscale framework at the brain network-level, linking molecular/cellular (bottom-up) to systems (top-down) level data for the correlative archeology of the human mind.

The deep past in the virtual present: developing an interdisciplinary approach towards understanding the psychological foundations of palaeolithic cave art

Virtual Reality (VR) has vast potential for developing systematic, interdisciplinary studies to understand ephemeral behaviours in the archaeological record, such as the emergence and development of visual culture. Upper Palaeolithic cave art forms the most robust record for investigating this and the methods of its production, themes, and temporal and spatial changes have been researched extensively, but without consensus over its functions or meanings. More compelling arguments draw from visual psychology and posit that the immersive, dark conditions of caves elicited particular psychological responses, resulting in the perception-and depiction-of animals on suggestive features of cave walls. Our research developed and piloted a novel VR experiment that allowed participants to perceive 3D models of cave walls, with the Palaeolithic art digitally removed, from El Castillo cave (Cantabria, Spain). Results indicate that modern participants' visual attention corresponded to the same topographic features of cave walls utilised by Palaeolithic artists, and that they perceived such features as resembling animals. Although preliminary, our results support the hypothesis that pareidolia-a product of our cognitive evolution-was a key mechanism in Palaeolithic art making, and demonstrates the potential of interdisciplinary VR research for understanding the evolution of art, and demonstrate the potential efficacy of the methodology.

Formation processes, fire use, and patterns of human occupation across the Middle Palaeolithic (MIS 5a-5b) of Gruta da Oliveira (Almonda karst system, Torres Novas, Portugal)

Gruta da Oliveira features a c. 13 m-thick infilling that includes a c. 6.5 m-thick archaeological deposit (the "Middle Palaeolithic sequence" complex), which Bayesian modelling of available dating results places in MIS 5a (layers 7-14) and MIS 5b (layers 15-25), c. 71,000-93,000 years ago. The accumulation primarily consists of sediment washed in from the slope through gravitational processes and surface dynamics. The coarse fraction derives from weathering of the cave's limestone bedrock. Tectonic activity and structural instability caused the erosional retreat of the scarp face, explaining the large, roof-collapsed rock masses found through the stratification. The changes in deposition and diagenesis observed across the archaeological sequence are minor and primarily controlled by local factors and the impact of humans and other biological agents. Pulses of stadial accumulation-reflected in the composition of the assemblages of hunted ungulates, mostly open-country and rocky terrain taxa (rhino, horse, ibex)-alternate with interstadial hiatuses-during which carbonate crusts and flowstone formed. Humans were active at the cave throughout, but occupation was intermittent, which allowed for limited usage by carnivores when people visited less frequently. During the accumulation of layers 15-25 (c. 85,000-93,000 years ago), the carnivore guild was dominated by wolf and lion, while brown bear and lynx predominate in layers 7-14 (c. 71,000-78,000 years ago). In the excavated areas, conditions for residential use were optimal during the accumulation of layers 20-22 (c. 90,000-92,000 years ago) and 14 (c. 76,000-78,000 years ago), which yielded dense, hearth-focused scatters of stone tools and burnt bones. The latter are ubiquitous, adding to the growing body of evidence that Middle Palaeolithic Neandertals used fire in regular, consistent manner. The patterns of site usage revealed at Gruta da Oliveira are no different from those observed 50,000 years later in comparable early Upper Palaeolithic and Solutrean cave sites of central Portugal.

Measuring ancient technological complexity and its cognitive implications using Petri nets

We implement a method from computer sciences to address a challenge in Paleolithic archaeology: how to infer cognition differences from material culture. Archaeological material culture is linked to cognition, and more complex ancient technologies are assumed to have required complex cognition. We present an application of Petri net analysis to compare Neanderthal tar production technologies and tie the results to cognitive requirements. We applied three complexity metrics, each relying on their own unique definitions of complexity, to the modeled production processes. Based on the results, we propose that Neanderthal technical cognition may have been analogous to that of contemporary modern humans. This method also enables us to distinguish the high-order cognitive functions combining traits like planning, inhibitory control, and learning that were likely required by different ancient technological processes. The Petri net approach can contribute to our understanding of technology and cognitive evolution as it can be used on different materials and technologies, across time and species.

Drawing as a versatile cognitive tool

Drawing is a cognitive tool that makes the invisible contents of mental life visible. Humans use this tool to produce a remarkable variety of pictures, from realistic portraits to schematic diagrams. Despite this variety and the prevalence of drawn images, the psychological mechanisms that enable drawings to be so versatile have yet to be fully explored. In this Review, we synthesize contemporary work in multiple areas of psychology, computer science and neuroscience that examines the cognitive processes involved in drawing production and comprehension. This body of findings suggests that the balance of contributions from perception, memory and social inference during drawing production varies depending on the situation, resulting in some drawings that are more realistic and other drawings that are more abstract. We also consider the use of drawings as a research tool for investigating various aspects of cognition, as well as the role that drawing has in facilitating learning and communication. Taken together, information about how drawings are used in different contexts illuminates the central role of visually grounded abstractions in human thought and behaviour.

A 36,200-year-old carving from Grotte des Gorges, Amange, Jura, France

The earliest European carvings, made of mammoth ivory, depict animals, humans, and anthropomorphs. They are found at Early Aurignacian sites of the Swabian Jura in Germany. Despite the wide geographical spread of the Aurignacian across Europe, these carvings have no contemporaneous counterparts. Here, we document a small, intriguing object, that sheds light on this uniqueness. Found at the Grotte des Gorges (Jura, France), in a layer sandwiched between Aurignacian contexts and dated to c. 36.2 ka, the object bears traces of anthropogenic modifications indicating intentional carving. Microtomographic, microscopic, three-dimensional roughness and residues analyses reveal the carving is a fragment of a large ammonite, which was modified to represent a caniformia head decorated with notches and probably transported for long time in a container stained with ochre. While achieving Swabian Jura-like miniaturization, the Grotte des Gorges specimen displays original features, indicating the craftsman emulated ivory carvings while introducing significant technical, thematic, and stylistic innovations. This finding suggests a low degree of cultural connectivity between Early Aurignacian hunter-gatherer groups in the production of their symbolic material culture. The pattern conforms to the existence of cultural boundaries limiting the transmission of symbolic practices while leaving space for the emergence of original regional expressions.

The earliest unambiguous Neanderthal engravings on cave walls: La Roche-Cotard, Loire Valley, France

Here we report on Neanderthal engravings on a cave wall at La Roche-Cotard (LRC) in central France, made more than 57±3 thousand years ago. Following human occupation, the cave was completely sealed by cold-period sediments, which prevented access until its discovery in the 19th century and first excavation in the early 20th century. The timing of the closure of the cave is based on 50 optically stimulated luminescence ages derived from sediment collected inside and from around the cave. The anthropogenic origin of the spatially-structured, non-figurative marks found within the cave is confirmed using taphonomic, traceological and experimental evidence. Cave closure occurred significantly before the regional arrival of H. sapiens, and all artefacts from within the cave are typical Mousterian lithics; in Western Europe these are uniquely attributed to H. neanderthalensis. We conclude that the LRC engravings are unambiguous examples of Neanderthal abstract design.

From fossils to mind

Fossil endocasts record features of brains from the past: size, shape, vasculature, and gyrification. These data, alongside experimental and comparative evidence, are needed to resolve questions about brain energetics, cognitive specializations, and developmental plasticity. Through the application of interdisciplinary techniques to the fossil record, paleoneurology has been leading major innovations. Neuroimaging is shedding light on fossil brain organization and behaviors. Inferences about the development and physiology of the brains of extinct species can be experimentally investigated through brain organoids and transgenic models based on ancient DNA. Phylogenetic comparative methods integrate data across species and associate genotypes to phenotypes, and brains to behaviors. Meanwhile, fossil and archeological discoveries continuously contribute new knowledge. Through cooperation, the scientific community can accelerate knowledge acquisition. Sharing digitized museum collections improves the availability of rare fossils and artifacts. Comparative neuroanatomical data are available through online databases, along with tools for their measurement and analysis. In the context of these advances, the paleoneurological record provides ample opportunity for future research. Biomedical and ecological sciences can benefit from paleoneurology's approach to understanding the mind as well as its novel research pipelines that establish connections between neuroanatomy, genes and behavior.

Quantum Leaps in Human Biocultural Evolution and the Relationship to Cranial Capacity

The evolution of the genus Homo can only be understood by considering both of the inheritance systems that interact to shape human nature: biology and culture. While growing intellectual abilities are a key factor of human evolution, they are rarely contrasted with cultural progress. Cranial capacity data of 193 hominin fossils from the last seven million years and artefacts of increasing number and complexity in the archaeological record are used to demonstrate the concordant progression of brain-size increase and cultural development, starting approximately two million years ago. Our biocultural evolution shows a number of quantum leaps along the time axis applying to both domains. At first, humans left the canonical evolutionary pathway, which pertains to all other organisms, by enhancing their fitness using sophisticated tools and fire; secondly, they turned into a symbolic species; and finally, humanity now faces a new challenge: "intentional evolution". Chronologically, these quantum leaps correspond to cranial capacity data used here as a proxy for cognitive performance. This contribution tries to demonstrate this parallel development and argues for a simple and generalized model of human biocultural evolution. An extrapolation of the model into the future shows that humans, as biological entities, will not necessarily persist.

Visual resemblance and interaction history jointly constrain pictorial meaning

How do drawings-ranging from detailed illustrations to schematic diagrams-reliably convey meaning? Do viewers understand drawings based on how strongly they resemble an entity (i.e., as images) or based on socially mediated conventions (i.e., as symbols)? Here we evaluate a cognitive account of pictorial meaning in which visual and social information jointly support visual communication. Pairs of participants used drawings to repeatedly communicate the identity of a target object among multiple distractor objects. We manipulated social cues across three experiments and a full replication, finding that participants developed object-specific and interaction-specific strategies for communicating more efficiently over time, beyond what task practice or a resemblance-based account alone could explain. Leveraging model-based image analyses and crowdsourced annotations, we further determined that drawings did not drift toward "arbitrariness," as predicted by a pure convention-based account, but preserved visually diagnostic features. Taken together, these findings advance psychological theories of how successful graphical conventions emerge.

Possibilities of Direct Dating of Rock Art in the Khakass-Minusinsk Basin

The study addresses modern methods of absolute dating of rock art. We review prospective approaches to dating petroglyphs under various conditions: AMS, OSL, uranium-thorium, and cosmogenic isotope. Not so much methods per se are discussed as principles of their application to certain reliably dated rock art sites of various periods in Europe, Asia, America, and Australia. Examples of satisfactory outcomes in international practice are cited alongside our assessment of prospects and limitations to be considered with regard to the method of dating the earliest petroglyphs and rock paintings in the Khakass-Minusinsk Basin. The review suggests that the basic conditions for the use of the uranium-thorium method are not met, the AMS method requires a preliminary analysis of the context, whereas OSL and cosmogenic isotope method are the most prospective.

What made us "hunter-gatherers of words"

This paper makes three interconnected claims: (i) the "human condition" cannot be captured by evolutionary narratives that reduce it to a recent 'cognitive modernity', nor by narratives that eliminates all cognitive differences between us and out closest extinct relatives, (ii) signals from paleogenomics, especially coming from deserts of introgression but also from signatures of positive selection, point to the importance of mutations that impact neurodevelopment, plausibly leading to temperamental differences, which may impact cultural evolutionary trajectories in specific ways, and (iii) these trajectories are expected to affect the language phenotypes, modifying what is being learned and how it is put to use. In particular, I hypothesize that these different trajectories influence the development of symbolic systems, the flexible ways in which symbols combine, and the size and configurations of the communities in which these systems are put to use.

The evolutionary origin of psychosis

Imagination, the driving force of creativity, and primary psychosis are human-specific, since we do not observe behaviors in other species that would convincingly suggest they possess the same traits. Both these traits have been linked to the function of the prefrontal cortex, which is the most evolutionarily novel region of the human brain. A number of evolutionarily novel genetic and epigenetic changes that determine the human brain-specific structure and function have been discovered in recent years. Among them are genomic loci subjected to increased rates of single nucleotide substitutions in humans, called human accelerated regions. These mostly regulatory regions are involved in brain development and sometimes contain genetic variants that confer a risk for schizophrenia. On the other hand, neuroimaging data suggest that mind wandering and related phenomena (as a proxy of imagination) are in many ways similar to rapid eye movement dreaming, a function also present in non-human species. Furthermore, both functions are similar to psychosis in several ways: for example, the same brain areas are activated both in dreams and visual hallucinations. In the present Perspective we hypothesize that imagination is an evolutionary adaptation of dreaming, while primary psychosis results from deficient control by higher-order brain areas over imagination. In the light of this, human accelerated regions might be one of the key drivers in evolution of human imagination and the pathogenesis of psychotic disorders.

Organization of residential space, site function variability, and seasonality of activities among MIS 5 Iberian Neandertals

Whether ethnoarcheological models of hunter-gatherer mobility, landscape use, and structuration of the inhabited space are relevant to the archeology of Neandertals and the Middle Paleolithic remains controversial. The thin lenses of hearth-associated stone tools and faunal remains excavated in sub-complex AS5 of Cueva Antón (Murcia, Spain) significantly advance these debates. Dated to 77.8-85.1 ka, these living floors are interstratified in river-accumulated sands and were buried shortly after abandonment by low-energy inundation events, with minimal disturbance and negligible palimpsest formation. Stone tools were made and ergonomically modified to fit tasks; their spatial distributions and use-wear reveal hearth-focused activities and a division of the inhabited space into resting and working areas. Site function varied with season of the year: units III-i/j1 and III-i/j2-3 record winter visits focused on filleting and hide processing, while woodworking predominated in unit III-b/d, which subsumes visits to the site over the course of at least one winter, one spring, and one summer. These snapshots of Neandertal behavior match expectations derived from the ethnographic and Upper Paleolithic records for the lifeways of hunter-gatherers inhabiting temperate regions with a markedly seasonal climate.

Human TKTL1 implies greater neurogenesis in frontal neocortex of modern humans than Neanderthals

Neanderthal brains were similar in size to those of modern humans. We sought to investigate potential differences in neurogenesis during neocortex development. Modern human transketolase-like 1 (TKTL1) differs from Neanderthal TKTL1 by a lysine-to-arginine amino acid substitution. Using overexpression in developing mouse and ferret neocortex, knockout in fetal human neocortical tissue, and genome-edited cerebral organoids, we found that the modern human variant, hTKTL1, but not the Neanderthal variant, increases the abundance of basal radial glia (bRG) but not that of intermediate progenitors (bIPs). bRG generate more neocortical neurons than bIPs. The hTKTL1 effect requires the pentose phosphate pathway and fatty acid synthesis. Inhibition of these metabolic pathways reduces bRG abundance in fetal human neocortical tissue. Our data suggest that neocortical neurogenesis in modern humans differs from that in Neanderthals.

Molecular archaeology of human cognitive traits

The brains and minds of our human ancestors remain inaccessible for experimental exploration. Therefore, we reconstructed human cognitive evolution by projecting nonsynonymous/synonymous rate ratios (ω values) in mammalian phylogeny onto the anatomically modern human (AMH) brain. This atlas retraces human neurogenetic selection and allows imputation of ancestral evolution in task-related functional networks (FNs). Adaptive evolution (high ω values) is associated with excitatory neurons and synaptic function. It shifted from FNs for motor control in anthropoid ancestry (60-41 mya) to attention in ancient hominoids (26-19 mya) and hominids (19-7.4 mya). Selection in FNs for language emerged with an early hominin ancestor (7.4-1.7 mya) and was later accompanied by adaptive evolution in FNs for strategic thinking during recent (0.8 mya-present) speciation of AMHs. This pattern mirrors increasingly complex cognitive demands and suggests that co-selection for language alongside strategic thinking may have separated AMHs from their archaic Denisovan and Neanderthal relatives.

The nature and chronology of human occupation at the Galerías Bajas, from Cueva de Ardales, Malaga, Spain

The Cueva de Ardales is a hugely important Palaeolithic site in the south of the Iberian Peninsula owing to its rich inventory of rock art. From 2011–2018, excavations were carried out in the cave for the first time ever by a Spanish-German research team. The excavation focused on the entrance area of the cave, where the largest assemblage of non-figurative red paintings in the cave is found. A series of 50 AMS dates from the excavations prove a long, albeit discontinuous, occupation history spanning from the Middle Palaeolithic to the Neolithic. The dating of the Middle Palaeolithic layers agrees with the U/Th dating of some red non-figurative paintings in the entrance area. In addition, a large assemblage of ochre lumps was discovered in the Middle Palaeolithic layers. Human visits of the cave in the Gravettian and Solutrean can be recognized, but evidence from the Aurignacian and Magdalenian cannot be confirmed with certainty. The quantity and nature of materials found during the excavations indicate that Cueva de Ardales was not a campsite, but was mainly visited to carry out non-domestic tasks, such as the production of rock art or the burial of the dead.

The Sustainability of Rock Art: Preservation and Research

Rock art is a widespread cultural heritage, representing an immovable element of the material culture created on natural rocky supports. Paintings and petroglyphs can be found within caves and rock shelters or in open-air contexts and for that reason they are not isolated from the processes acting at the Earth surface. Consequently, rock art represents a sort of ecosystem because it is part of the complex and multidirectional interplay between the host rock, pigments, environmental parameters, and microbial communities. Such complexity results in several processes affecting rock art; some of them contribute to its destruction, others to its preservation. To understand the effects of such processes an interdisciplinary scientific approach is needed. In this contribution, we discuss the many processes acting at the rock interface—where rock art is present—and the multifaceted possibilities of scientific investigations—non-invasive or invasive—offered by the STEM disciplines. Finally, we suggest a sustainable approach to investigating rock art allowing to understand its production as well as its preservation and eventually suggest strategies to mitigate the risks threatening its stability.

EXPRESS: Investigating the Role of Working Memory Resources across Aesthetic and Non-Aesthetic Judgments

Aesthetic judgments dominate much of daily life by guiding how we evaluate objects, people, and experiences in our environment. One key question that remains unanswered is the extent to which more specialised or largely general cognitive resources support aesthetic judgments. To investigate this question in the context of working memory, we examined the extent to which a working memory load produces similar or different response time interference on aesthetic compared to non-aesthetic judgments. Across three pre-registered experiments that used Bayesian multi-level modelling approaches (N>100 per experiment), we found clear evidence that a working memory load produces similar response time interference on aesthetic judgments relative to non-aesthetic (motion) judgments. We also showed that this similarity in processing across aesthetic versus non-aesthetic judgments holds across variations in the form of art (people vs landscape; Exps. 1-3), medium type (artwork vs photographs; Exp. 2) and load content (art images vs letters; Exps. 1-3). These findings suggest that across a range of experimental contexts, as well as different processing streams in working memory (e.g., visual vs verbal), aesthetic and motion judgments commonly rely on a domain-general cognitive system, rather than a system that is more specifically tied to aesthetic judgments. In doing so, these findings shine new light on the working memory resources that supports aesthetic judgments, as well as how domain-general cognitive systems operate more generally in cognition.

Evaluating landscape knowledge and lithic resource selection at the French Middle Paleolithic site of the Bau de l'Aubesier

We report on the application of a novel approach to exploring the degree of landscape knowledge, wayfinding abilities, and the nature of decision-making processes reflected in the utilization of stone resources in the French Middle Paleolithic. Specifically, we use data from the site of the Bau de l'Aubesier to explore the reasons why a majority of the 350 raw material sources cataloged in the surrounding region appear not to have been utilized, including several located near the site and yielding high-quality lithic materials. To this end, we focus on the spatial relationships between sources as an explanatory variable, operationalized in terms of minimum travel times. Using geographic information system software and a generalized linear model of resource selection derived from the Bau assemblages, we compute source utilization probabilities from the perspective of hominins located off-site. We do so under three optimization scenarios, factoring in the intrinsic characteristics (e.g., quality) and time required to reach each source on the way to the Bau. More generally, we find that in slightly more than 50% of cases, seemingly viable sources may have been ignored simply because the minimum cost path leading back to the Bau passes through or requires only minimal deviations to reach, higher quality options. More generally, we found that throughout the entire region, a cost/benefit analysis of competing sources favors those from source areas known to have been utilized. Virtually all the available information on lithic procurement at the Bau is consistent with a model of landscape utilization premised on detailed knowledge of a very large area, an ability to accurately estimate travel times between locations, and a pragmatic strategy of stone resource exploitation based on minimizing costs (travel and search times) and maximizing utility.

Dialogic Book-Sharing as a Privileged Intersubjective Space

Parental reading to young children is well-established as being positively associated with child cognitive development, particularly their language development. Research indicates that a particular, "intersubjective," form of using books with children, "Dialogic Book-sharing" (DBS), is especially beneficial to infants and pre-school aged children, particularly when using picture books. The work on DBS to date has paid little attention to the theoretical and empirical underpinnings of the approach. Here, we address the question of what processes taking place during DBS confer benefits to child development, and why these processes are beneficial. In a novel integration of evidence, ranging from non-human primate communication through iconic gestures and pointing, archaeological data on Pre-hominid and early human art, to experimental and naturalistic studies of infant attention, cognitive processing, and language, we argue that DBS entails core characteristics that make it a privileged intersubjective space for the promotion of child cognitive and language development. This analysis, together with the findings of DBS intervention studies, provides a powerful intellectual basis for the wide-scale promotion of DBS, especially in disadvantaged populations.

Neanderthal Fossils, Mobile Toolkit and a Hyena Den: The Archaeological Assemblage of Lateral Gallery 1 in Cova Del Gegant (NE Iberian Peninsula)

Lateral Gallery 1 (GL1) in Cova del Gegant is a Middle Palaeolithic assemblage yielding diagnostic Neanderthal remains, together with Mousterian tools and faunal remains. It is a good archive for evaluating the environmental conditions of the coastal areas during MIS 4 and MIS 3 in the NE of the Iberian Peninsula, and also the Neanderthals’ behaviour and mobility. Here we provide a comprehensive assessment of all of the data available from GL1, such as lithics, human remains, fauna and chronostratigraphic details. The biotic ecofacts studied point to the development of a coastal plain in front of the cave and indicate that local conditions likely favoured a large variety of ecosystems characterised by open environments and woodland-edge taxa, and favoured repeated visits by humans during the Middle Palaeolithic. The evidence suggests that the gallery was mainly used by carnivores, such as hyenas, and also by Neanderthals as a brief stopping place, in view of the presence of transported and abandoned ergonomic lithic artifacts and/or the placement of bodies (or parts of bodies). The regional context suggests high human mobility and emphasises the variability of Neanderthal behaviour.

The nature and chronology of human occupation at the Galerías Bajas, from Cueva de Ardales, Malaga, Spain

The Cueva de Ardales is a hugely important Palaeolithic site in the south of the Iberian Peninsula owing to its rich inventory of rock art. From 2011-2018, excavations were carried out in the cave for the first time ever by a Spanish-German research team. The excavation focused on the entrance area of the cave, where the largest assemblage of non-figurative red paintings in the cave is found. A series of 50 AMS dates from the excavations prove a long, albeit discontinuous, occupation history spanning from the Middle Palaeolithic to the Neolithic. The dating of the Middle Palaeolithic layers agrees with the U/Th dating of some red non-figurative paintings in the entrance area. In addition, a large assemblage of ochre lumps was discovered in the Middle Palaeolithic layers. Human visits of the cave in the Gravettian and Solutrean can be recognized, but evidence from the Aurignacian and Magdalenian cannot be confirmed with certainty. The quantity and nature of materials found during the excavations indicate that Cueva de Ardales was not a campsite, but was mainly visited to carry out non-domestic tasks, such as the production of rock art or the burial of the dead.

Evolution of genetic networks for human creativity

The genetic basis for the emergence of creativity in modern humans remains a mystery despite sequencing the genomes of chimpanzees and Neanderthals, our closest hominid relatives. Data-driven methods allowed us to uncover networks of genes distinguishing the three major systems of modern human personality and adaptability: emotional reactivity, self-control, and self-awareness. Now we have identified which of these genes are present in chimpanzees and Neanderthals. We replicated our findings in separate analyses of three high-coverage genomes of Neanderthals. We found that Neanderthals had nearly the same genes for emotional reactivity as chimpanzees, and they were intermediate between modern humans and chimpanzees in their numbers of genes for both self-control and self-awareness. 95% of the 267 genes we found only in modern humans were not protein-coding, including many long-non-coding RNAs in the self-awareness network. These genes may have arisen by positive selection for the characteristics of human well-being and behavioral modernity, including creativity, prosocial behavior, and healthy longevity. The genes that cluster in association with those found only in modern humans are over-expressed in brain regions involved in human self-awareness and creativity, including late-myelinating and phylogenetically recent regions of neocortex for autobiographical memory in frontal, parietal, and temporal regions, as well as related components of cortico-thalamo-ponto-cerebellar-cortical and cortico-striato-cortical loops. We conclude that modern humans have more than 200 unique non-protein-coding genes regulating co-expression of many more protein-coding genes in coordinated networks that underlie their capacities for self-awareness, creativity, prosocial behavior, and healthy longevity, which are not found in chimpanzees or Neanderthals.

A Global Perspective on Sustainable Show Cave Tourism

Caves are among the most visited geological features in the world, attracting over 70 million people every year in more than 1,200 caves worldwide, and amounting up to 800 million Euros in entrance fees alone. The global business of show caves employs roughly 25,000 people directly (management, guides), and at least 100 times more people if we consider the connected tourist activities (souvenir shops, local transport, travel agencies, restaurants, and bars). It is estimated that the whole show cave business has a global commercial value of roughly 2 billion Euros, a number that is increasing constantly. Show caves are generally fragile ecosystems, and care should be taken in their management to safeguard their value for future generations. The international scientific (speleological) community has issued international guidelines for the sustainable development and management of show caves eight years ago, but their application is still far from being applied globally, especially in developing and least developed countries. Cave tourism is expected to increase, especially in countries where caves are abundant but not yet considered as tourist attractions, and where economic and political instability slow down the development of tourism. There are still a lot of possibilities for the opening of new show caves, especially in countries with low Gross Domestic Income (GDI), but their management needs to be sustainable, so that caves become a means of sustaining local economies, educating people on these fragile geo- and ecosystems, and protecting contemporarily their scientific and cultural heritage for future generations.

Evolutionary origin and the development of consciousness

This review seeks to combine advances in anthropology and neuroscience to investigate the adaptive value of human consciousness. It uses an interdisciplinary perspective on the origin of consciousness to refute the most common fallacies in considering consciousness, particularly, disregarding the evolutionary origin of the subjective reality in looking for the neural correlates of consciousness and divorcing studies in neuroscience and behavioural sciences. Various explanations linked to consciousness in the field of neuroscience, supplemented with the theoretical explanation of an experience as an ongoing process of overlap between intrinsic neural dynamics and stimulation can be summarised as the stochastic dynamics of one's control system experienced by the individual in the form of subjective reality. This framework elaborates on the world-brain research program and lays foundation for the quantitative description of one's qualitative feelings and naturalistic science of consciousness. Furthermore, this study highlights the philosophical perspective of the inseparability between the physical correlates and the subjective reality contributing to the realistic ontology of conscious processes.

Reconstructing Neanderthal diet: The case for carbohydrates

Evidence for plants rarely survives on Paleolithic sites, while animal bones and biomolecular analyses suggest animal produce was important to hominin populations, leading to the perspective that Neanderthals had a very-high-protein diet. But although individual and short-term survival is possible on a relatively low-carbohydrate diet, populations are unlikely to have thrived and reproduced without plants and the carbohydrates they provide. Today, nutritional guidelines recommend that around half the diet should be carbohydrate, while low intake is considered to compromise physical performance and successful reproduction. This is likely to have been the same for Paleolithic populations, highlighting an anomaly in that the basic physiological recommendations do not match the extensive archaeological evidence. Neanderthals had large, energy-expensive brains and led physically active lifestyles, suggesting that for optimal health they would have required high amounts of carbohydrates. To address this anomaly, we begin by outlining the essential role of carbohydrates in the human reproduction cycle and the brain and the effects on physical performance. We then evaluate the evidence for resource availability and the archaeological evidence for Neanderthal diet and investigate three ways that the anomaly between the archaeological evidence and the hypothetical dietary requirements might be explained. First, Neanderthals may have had an as yet unidentified genetic adaptation to an alternative physiological method to spare blood glucose and glycogen reserves for essential purposes. Second, they may have existed on a less-than-optimum diet and survived rather than thrived. Third, the methods used in dietary reconstruction could mask a complex combination of dietary plant and animal proportions. We end by proposing that analyses of Paleolithic diet and subsistence strategies need to be grounded in the minimum recommendations throughout the life course and that this provides a context for interpretation of the archaeological evidence from the behavioral and environmental perspectives.

The Saliency of Snake Scales and Leopard Rosettes to Infants: Its Relevance to Graphical Patterns Portrayed in Prehistoric Art

Geometrically arranged spots and crosshatched incised lines are frequently portrayed in prehistoric cave and mobiliary art. Two experiments examined the saliency of snake scales and leopard rosettes to infants that are perceptually analogous to these patterns. Experiment 1 examined the investigative behavior of 23 infants at three daycare facilities. Four plastic jars (15×14.5cm) with snake scales, leopard rosettes, geometric plaid, and plain patterns printed on yellowish-orange paper inside were placed individually on the floor on separate days during playtime. Fourteen 7–15-month-old infants approached each jar hesitantly and poked it before handling it for five times, the criterion selected for statistical analyses of poking frequency. The jars with snake scales and leopard rosettes yielded reliably higher poking frequencies than the geometric plaid and plain jars. The second experiment examined the gaze and grasping behavior of 15 infants (spanning 5months of age) seated on the laps of their mothers in front of a table. For paired comparisons, the experimenter pushed two of four upright plastic cylinders (13.5×5.5cm) with virtually the same colored patterns simultaneously toward each infant for 6s. Video recordings indicated that infants gazed significantly longer at the cylinders with snake scales and leopard rosettes than the geometric plaid and plain cylinders prior to grasping them. Logistic regression of gaze duration predicting cylinder choice for grasping indicated that seven of 24 paired comparisons were not significant, all of which involved choices of cylinders with snake scales and leopard rosettes that diverted attention before reaching. Evidence that these biological patterns are salient to infants during an early period of brain development might characterize the integration of subcortical and neocortical visual processes known to be involved in snake recognition. In older individuals, memorable encounters with snakes and leopards coupled with the saliency of snake scales and leopard rosettes possibly biased artistic renditions of similar patterns during prehistoric times.

Direct Dating of Chinese Immovable Cultural Heritage

The most extensive corpus of ancient immovable cultural heritage is that of global rock art. Estimating its age has traditionally been challenging, rendering it difficult to integrate archaeological evidence of early cultural traditions. The dating of Chinese rock art by ‘direct methods’ began in the late 1990s in Qinghai Province. Since then, China has acquired the largest body of direct dating information about the rock art of any country. The establishment of the International Centre for Rock Art Dating at Hebei Normal University has been the driving force in this development, with its researchers accounting for most of the results. This centre has set the highest standards in rock art age estimation. Its principal method, microerosion analysis, secured the largest number of determinations, but it has also applied other methods. Its work with uranium-thorium analysis of carbonate precipitates in caves is of particular significance because it tested this widely used method. The implications of this work are wide-ranging. Most direct-dating of rock art has now become available from Henan, but results have also been reported from Heilongjiang, Inner Mongolia, Ningxia, Jiangsu, Hubei, Guangxi, Yunnan, Qinghai, Tibet, and Xinjiang. Intensive work by several teams is continuing and is expected to result in a significantly better understanding of China’s early immovable cultural heritage.

Comment on "A global environmental crisis 42,000 years ago"

Cooper et al. (Research Articles, 19 February 2021, p. 811) propose that a weakening geomagnetic field prior to the Laschamps Excursion explains megafaunal extinctions and human cultural changes that they claim happened 42,000 years ago. However, these authors misrepresent both the data and interpretations of cited work on extinctions and human cultural changes, so the specific claims they make about extinctions and cultural changes are false.

The Ape That Lived to Tell the Tale. The Evolution of the Art of Storytelling and Its Relationship to Mental Time Travel and Theory of Mind

Engaging in the art of creating and telling stories is a defining behaviour of humankind. Humans have been sharing stories with each other, with and without words, since the dawn of recorded history, but the cognitive foundations of the behaviour can be traced deeper into our past. The emergence of stories can be strongly linked to Mental Time Travel (the ability to recall the past and imagine the future) and plays a key role in our ability to communicate past, present and future scenarios with other individuals, within and beyond our lifetimes. Stories are products engraved within the concept of time, constructed to elucidate the past experiences of the self, but designed with the future in mind, thus imparting lessons of such experiences to the receiver. By being privy to the experiences of others, humans can imagine themselves in a similar position to the protagonist of the story, thus mentally learning from an experience they might have never encountered other than in the mind's eye. Evolutionary Psychology investigates how the engagement in artistic endeavours by our ancestors in the Pleistocene granted them an advantage when confronted with obstacles that challenged their survival or reproductive fitness and questions whether art is an adaptation of the human mind or a spandrel of other cognitive adaptations. However, little attention has been placed on the cognitive abilities that might have been imperative for the development of art. Here, we examine the relationship between art, storytelling, Mental Time Travel and Theory of Mind (i.e., the ability to attribute mental states to others). We suggest that Mental Time Travel played a key role in the development of storytelling because through stories, humans can fundamentally transcend their present condition, by being able to imagine different times, separate realities, and place themselves and others anywhere within the time space continuum. We argue that the development of a Theory of Mind also sparked storytelling practises in humans as a method of diffusing the past experiences of the self to others whilst enabling the receiver to dissociate between the past experiences of others and their own, and to understand them as lessons for a possible future. We propose that when artistic products rely on storytelling in form and function, they ought to be considered separate from other forms of art whose appreciation capitalise on our aesthetic preferences.

The ecology and bioactivity of some Greco-Roman medicinal minerals: the case of Melos earth pigments

Mineral compounds, as pigments and therapeutics, appeared regularly in the technical and medical texts of the Greco-Roman (G-R) world. We have referred to them as 'G-R medicinal minerals' and we suggest that despite their seeming familiarity, there are actually many unknowns regarding their precise nature and/or purported pharmacological attributes. Earth pigments are part of that group. This paper presents a brief overview of our work over the past twenty years relating to: a. the attempt to locate a select number of them in the places of their origin; b. their chemical/mineralogical characterization; c. the study of their ecology via the identification of the microorganisms surrounding them; d. their testing as antibacterials against known pathogens. In the process, and to fulfil the above, we have developed a novel methodological approach which includes a range of analytical techniques used across many disciplines (mineralogy, geochemistry, DNA extraction and microbiology). This paper focuses on a select number of earth pigments deriving from the island of Melos in the SW Aegean, celebrated in antiquity for its Melian Earth, a white pigment, and asks whether they might display antibacterial activity. We demonstrate that some (but not all) yellow, green and black earth pigments do. We also show that the manner in which they were dispensed (as powders or leachates) was equally important. The results, although preliminary, are informative. Given their use since deep time, earth pigments have never lost their relevance. We suggest that the study of their ecology/mineralogy and potential bioactivity allows for a better understanding of how our perception of them, as both pigments and therapeutics, may have evolved.

A 51,000-year-old engraved bone reveals Neanderthals' capacity for symbolic behaviour

While there is substantial evidence for art and symbolic behaviour in early Homo sapiens across Africa and Eurasia, similar evidence connected to Neanderthals is sparse and often contested in scientific debates. Each new discovery is thus crucial for our understanding of Neanderthals' cognitive capacity. Here we report on the discovery of an at least 51,000-year-old engraved giant deer phalanx found at the former cave entrance of Einhornhöhle, northern Germany. The find comes from an apparent Middle Palaeolithic context that is linked to Neanderthals. The engraved bone demonstrates that conceptual imagination, as a prerequisite to compose individual lines into a coherent design, was present in Neanderthals. Therefore, Neanderthal's awareness of symbolic meaning is very likely. Our findings show that Neanderthals were capable of creating symbolic expressions before H. sapiens arrived in Central Europe.

The symbolic role of the underground world among Middle Paleolithic Neanderthals

Cueva de Ardales in Málaga, Spain, is one of the richest and best-preserved Paleolithic painted caves of southwestern Europe, containing over a thousand graphic representations. Here, we study the red pigment in panel II.A.3 of "Sala de las Estrellas," dated by U-Th to the Middle Paleolithic, to determine its composition, verify its anthropogenic nature, infer the associated behaviors, and discuss their implications. Using optical microscopy, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, micro-Raman spectroscopy, and X-ray diffraction, we analyzed a set of samples from the panel and compared them to natural coloring materials collected from the floor and walls of the cave. The conspicuously different texture and composition of the geological samples indicates that the pigments used in the paintings do not come from the outcrops of colorant material known in the cave. We confirm that the paintings are not the result of natural processes and show that the composition of the paint is consistent with the artistic activity being recurrent. Our results strengthen the hypothesis that Neanderthals symbolically used these paintings and the large stalagmitic dome harboring them over an extended time span.

The Superior Visual Perception Hypothesis: Neuroaesthetics of Cave Art

Cave Art in the Upper Paleolithic presents a boost of creativity and visual thinking. What can explain these savant-like paintings? The normal brain function in modern man rarely supports the creation of highly detailed paintings, particularly the convincing representation of animal movement, without extensive training and access to modern technology. Differences in neuro-signaling and brain anatomy between modern and archaic Homo sapiens could also cause differences in perception. The brain of archaic Homo sapiens could perceive raw detailed information without using pre-established top-down concepts, as opposed to the common understanding of the normal modern non-savant brain driven by top-down control. Some ancient genes preserved in modern humans may be expressed in rare disorders. Researchers have compared Cave Art with art made by people with autism spectrum disorder. We propose that archaic primary consciousness, as opposed to modern secondary consciousness, included a savant-like perception with a superior richness of details compared to modern man. Modern people with high frequencies of Neanderthal genes, have notable anatomical features such as increased skull width in the occipital and parietal visual areas. We hypothesize that the anatomical differences are functional and may allow a different path to visual perception.

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.

230Th dating of flowstone from Ignatievskaya Cave, Russia: Age constraints of rock art and paleoclimate inferences

Paleolithic antiquity of parietal art in Ignatievskaya cave, Southern Ural, is supported by its subject (Late Pleistocene animals) as well as by paleontological and palynological data, and 14C dates from cultural layers associated with artistic activity (17.8-16.3 cal ka BP; association is established by finds of ochre in these layers). However, three 14C dates of charcoal motifs yielded younger, Holocene ages (7.4-6.0 cal ka BP). In this study, we constrain the age of parietal art in the cave by 230Th dating of flowstone that brackets the paintings. Flowstone did not form in the cave between c. 78 and 10 ka BP, due to widespread permafrost in northern Eurasia at that time. Our 230Th dates do not support the middle Holocene age of art in Ignatievskaya cave and are consistent with its Upper Paleolithic antiquity instead.

A global environmental crisis 42,000 years ago

Geological archives record multiple reversals of Earth's magnetic poles, but the global impacts of these events, if any, remain unclear. Uncertain radiocarbon calibration has limited investigation of the potential effects of the last major magnetic inversion, known as the Laschamps Excursion [41 to 42 thousand years ago (ka)]. We use ancient New Zealand kauri trees (Agathis australis) to develop a detailed record of atmospheric radiocarbon levels across the Laschamps Excursion. We precisely characterize the geomagnetic reversal and perform global chemistry-climate modeling and detailed radiocarbon dating of paleoenvironmental records to investigate impacts. We find that geomagnetic field minima ~42 ka, in combination with Grand Solar Minima, caused substantial changes in atmospheric ozone concentration and circulation, driving synchronous global climate shifts that caused major environmental changes, extinction events, and transformations in the archaeological record.