Fire and grass-bedding construction 200 thousand years ago at Border Cave, South Africa

Ochre communities of practice in Stone Age Eswatini

Our species and other hominins have used earth mineral pigments since at least ~500,000 years ago, if not earlier. Its preservation and ubiquity within archaeological records across sub-Saharan Africa are well documented, but regional-scale networks of mineral selection, mining, transport, and use is an underdeveloped field. Here, we present a framework for interpreting regional variations within an overarching ochre-behavioral community of practice. Deep-time records of ochre provisioning span the final Middle Stone Age and Late Stone Age in modern day Eswatini, revealing longstanding cultural continuities in the intergenerational transmission of shared knowledge on landscapes, geology, and the desired physicochemical properties of mineral pigments. These communities of practice did not develop in isolation, and were part of a wider system of relations that were influenced and mediated by social interactions, such as technological learning, seasonal traveling, material culture exchange, and symbolic expression. We use compositional analyses to determine localized ochre procurement strategies and long-distance transport across a network of fifteen archaeological sites and mineral resources. Newly refined chronologies from Lion Cavern at Ngwenya using optically stimulated luminescence dating also reaffirm its antiquity as the oldest known evidence for intensive ochre mining worldwide (~48,000 years ago).

Primate archaeology 3.0

The new field of primate archaeology investigates the technological behavior and material record of nonhuman primates, providing valuable comparative data on our understanding of human technological evolution. Yet, paralleling hominin archaeology, the field is largely biased toward the analysis of lithic artifacts. While valuable comparative data have been gained through an examination of extant nonhuman primate tool use and its archaeological record, focusing on this one single aspect provides limited insights. It is therefore necessary to explore to what extent other non-technological activities, such as non-tool aided feeding, traveling, social behaviors or ritual displays, leave traces that could be detected in the archaeological record. Here we propose four new areas of investigation which we believe have been largely overlooked by primate archaeology and that are crucial to uncovering the full archaeological potential of the primate behavioral repertoire, including that of our own: (1) Plant technology; (2) Archaeology beyond technology; (3) Landscape archaeology; and (4) Primate cultural heritage. We discuss each theme in the context of the latest developments and challenges, as well as propose future directions. Developing a more "inclusive" primate archaeology will not only benefit the study of primate evolution in its own right but will aid conservation efforts by increasing our understanding of changes in primate-environment interactions over time.

The stratigraphy and formation of Middle Stone Age deposits in Cave 1B, Klasies River Main site, South Africa, with implications for the context, age, and cultural association of the KRM 41815/SAM-AP 6222 human mandible

Cave 1B, in the Klasies River Main site complex (KRM), is best known for the recovery of the KRM 41815/SAM-AP 6222 human mandible. After initial skepticism over the modernity of this specimen, it is accepted that the mix of archaic and modern traits it displays is characteristic of early Homo sapiens individuals. Different authors have associated this specimen with the Middle Stone Age (MSA) I and II/Mossel Bay cultural phases, but the published data do not allow an unambiguous attribution. KRM 41815's frequent use in studies of the evolution of the human mandible, and its well-developed chin, makes clarifying its age and context important objectives. The field and micromorphology observations presented here provide greater insight into the stratigraphy and formation of the sequence exposed in the PP38 excavation. There are three major divisions: the basal Light Brown Sand (LBS) Member (not excavated), the Rubble Sand (RS) Member (MSA I), and the Shell and Sand Dark Carbonized (SASDC) Submember (MSA II). Cultural stratigraphy based on lithic artifacts remains the only way to make secure (but broad) temporal correlations with the rest of the site complex. This investigation shows that a range of anthropogenic, geogenic, and biogenic processes contributed to the deposition and post-depositional alteration of the identified microfacies. Short depositional hiatuses are reasonably common, and a significant hiatus was identified between the RS and SASDC. The impact of post-depositional processes on the RS is significant, with anthropogenic deposits poorly preserved. In comparison, the SASDC is dominated by hearths contained within deposits rich in reworked anthropogenic materials known as carbonized partings. Small shell disposal features are also present. The distribution of these anthropogenic features suggests continuity in the management of space throughout the MSA II occupations, from before 110 ka. New stratigraphic correlations indicate that KRM 41815 is unambiguously associated with the MSA I. Therefore, it predates 110 ka, with a lower age limit potentially in Marine Isotope Stage 6.

The revolution that still isn't: The origins of behavioral complexity in Homo sapiens

The behavioral origins of Homo sapiens can be traced back to the first material culture produced by our species in Africa, the Middle Stone Age (MSA). Beyond this broad consensus, the origins, patterns, and causes of behavioral complexity in modern humans remain debated. Here, we consider whether recent findings continue to support popular scenarios of: (1) a modern human 'package,' (2) a gradual and 'pan-African' emergence of behavioral complexity, and (3) a direct connection to changes in the human brain. Our geographically structured review shows that decades of scientific research have continuously failed to find a discrete threshold for a complete 'modernity package' and that the concept is theoretically obsolete. Instead of a continent-wide, gradual accumulation of complex material culture, the record exhibits a predominantly asynchronous presence and duration of many innovations across different regions of Africa. The emerging pattern of behavioral complexity from the MSA conforms to an intricate mosaic characterized by spatially discrete, temporally variable, and historically contingent trajectories. This archaeological record bears no direct relation to a simplistic shift in the human brain but rather reflects similar cognitive capacities that are variably manifested. The interaction of multiple causal factors constitutes the most parsimonious explanation driving the variable expression of complex behaviors, with demographic processes such as population structure, size, and connectivity playing a key role. While much emphasis has been given to innovation and variability in the MSA record, long periods of stasis and a lack of cumulative developments argue further against a strictly gradualistic nature in the record. Instead, we are confronted with humanity's deep, variegated roots in Africa, and a dynamic metapopulation that took many millennia to reach the critical mass capable of producing the ratchet effect commonly used to define contemporary human culture. Finally, we note a weakening link between 'modern' human biology and behavior from around 300 ka ago.

Evidence for the cooking of fish 780,000 years ago at Gesher Benot Ya'aqov, Israel

Although cooking is regarded as a key element in the evolutionary success of the genus Homo, impacting various biological and social aspects, when intentional cooking first began remains unknown. The early Middle Pleistocene site of Gesher Benot Ya'aqov, Israel (marine isotope stages 18-20; ~0.78 million years ago), has preserved evidence of hearth-related hominin activities and large numbers of freshwater fish remains (>40,000). A taphonomic study and isotopic analyses revealed significant differences between the characteristics of the fish bone assemblages recovered in eight sequential archaeological horizons of Area B (Layer II-6 levels 1-7) and natural fish bone assemblages (identified in Area A). Gesher Benot Ya'aqov archaeological horizons II-6 L1-7 exhibited low fish species richness, with a clear preference for two species of large Cyprinidae (Luciobarbus longiceps and Carasobarbus canis) and the almost total absence of fish bones in contrast to the richness of pharyngeal teeth (>95%). Most of the pharyngeal teeth recovered in archaeological horizons II-6 L1-7 were spatially associated with 'phantom' hearths (clusters of burnt flint microartifacts). Size-strain analysis using X-ray powder diffraction provided evidence that these teeth had been exposed to low temperature (<500 °C), suggesting, together with the archaeological and taphonomic data, that the fish from the archaeological horizons of Area B had been cooked and consumed on site. This is the earliest evidence of cooking by hominins.

Adaptive Solutions to the Problem of Vulnerability During Sleep

Sleep is a behavioral state whose quantity and quality represent a trade-off between the costs and benefits this state provides versus the costs and benefits of wakefulness. Like many species, we humans are particularly vulnerable during sleep because of our reduced ability to monitor the external environment for nighttime predators and other environmental dangers. A number of variations in sleep characteristics may have evolved over the course of human history to reduce this vulnerability, at both the individual and group level. The goals of this interdisciplinary review paper are (1) to explore a number of biological/instinctual features of sleep that may have adaptive utility in terms of enhancing the detection of external threats, and (2) to consider relatively recent cultural developments that improve vigilance and reduce vulnerability during sleep and the nighttime. This paper will also discuss possible benefits of the proposed adaptations beyond vigilance, as well as the potential costs associated with each of these proposed adaptations. Finally, testable hypotheses will be presented to evaluate the validity of these proposed adaptations.

Homo sapiens origins and evolution in the Kalahari Basin, southern Africa

The Kalahari Basin, southern Africa preserves a rich archeological record of human origins and evolution spanning the Early, Middle and Late Pleistocene. Since the 1930s, several stratified and dated archeological sites have been identified and investigated, together with numerous open-air localities that provide landscape-scale perspectives. However, next to recent discoveries from nearby coastal regions, the Kalahari Basin has remained peripheral to debates about the origins of Homo sapiens. Though the interior region of southern Africa is generally considered to be less suitable for hunter-gatherer occupation than coastal and near-coastal regions, especially during glacial periods, the archeological record documents human presence in the Kalahari Basin from the Early Pleistocene onwards, and the region is not abandoned during glacial phases. Furthermore, many significant behavioral innovations have an early origin in the Kalahari Basin, which adds support to poly-centric, pan-African models for the emergence of our species.

Middle Pleistocene fire use: The first signal of widespread cultural diffusion in human evolution

Control of fire is one of the most important technological innovations within the evolution of humankind. The archaeological signal of fire use becomes very visible from around 400,000 y ago onward. Interestingly, this occurs at a geologically similar time over major parts of the Old World, in Africa, as well as in western Eurasia, and in different subpopulations of the wider hominin metapopulation. We interpret this spatiotemporal pattern as the result of cultural diffusion, and as representing the earliest clear-cut case of widespread cultural change resulting from diffusion in human evolution. This fire-use pattern is followed slightly later by a similar spatiotemporal distribution of Levallois technology, at the beginning of the African Middle Stone Age and the western Eurasian Middle Paleolithic. These archaeological data, as well as studies of ancient genomes, lead us to hypothesize that at the latest by 400,000 y ago, hominin subpopulations encountered one another often enough and were sufficiently tolerant toward one another to transmit ideas and techniques over large regions within relatively short time periods. Furthermore, it is likely that the large-scale social networks necessary to transmit complicated skills were also in place. Most importantly, this suggests a form of cultural behavior significantly more similar to that of extant Homo sapiens than to our great ape relatives.