Matthias A. Blessing

Technological complexity has been a continuous trope in archaeological research from its beginnings in the nineteenth century. Based on a concept of unidirectional cultural evolution, archaeological material was ordered along a linear progression from simple to complex. While creating hierarchies of extant populations based on the complexity of their tools is not overtly practiced in archaeology anymore, the same is not true for the deep past. The concept of behavioural modernity and research on human cognitive evolution is still partly founded on technological complexity. The turn away from technological complexity to symbolic behaviour in pursuing questions surrounding behavioural modernity and humanness was less a reaction to criticisms of the concept but served to maintain the hierarchical ranking between modern humans and extinct hominins. Here, we propose an alternative view on technological complexity that attempts to overcome linear hierarchies and lingering progressivist notions. By reviewing several measures of complexity alongside their analytical units and underlying definitions, we show that technological complexity is not suitable for creating a single hierarchy of artefacts, assemblages, or hominin species. The multitude of existing definitions, methods, and measures does not imply a fundamental flaw in these approaches but exemplifies the multidimensionality of technological complexity. We propose a new way of understanding multiple, justified measures for technological complexity through a heterarchical structure that allows various kinds of ranking to exist depending on context, need, scale, or function, including the potential for competing or even contradictory hierarchies. A heterarchical perspective on technological complexity asks ‘How were technologies or hominins complex?’ rather than ‘How complex were technologies and hominins relative to another?’ This approach can shed persistent historical bias and overcome simplistic dichotomies such as ‘us’ and ‘them’ in deep-time archaeology that hinder our ability to engage with questions about the becoming of humans in a meaningful way.

The selection and acquisition of suitable raw material constitute the first steps in stone tool technology. Previous ethnographical and archaeological research suggests that hominins in the Pleistocene primarily collected their stone materials while carrying out other activities. Direct provisioning for this purpose alone remains an outlier and is rarely demonstrated. Archaeological excavations coupled with multidisciplinary analyses at Jojosi in South Africa demonstrate that early modern humans undertook specific, repeated visits to a raw material source over tens of thousands of years for the exclusive purpose of obtaining hornfels. This rare, stratified, open-air locality features uniquely preserved lithic assemblages with abundant refits dating from ~220 ka to ~110 ka for the reduction and export of a single tool stone. The scope of these knapping activities is underscored by millions of Middle Stone Age hornfels artefacts paving the modern landscape. The consistent, specialised procurement of a single raw material at Jojosi already during the Middle Pleistocene challenges the standard model of embedded procurement for this period. These findings further show that key capacities of Homo sapiens , including increased long-term planning and behavioural plasticity in the interaction with the material world, emerged early in their evolutionary history.

Using Neanderthal symbolism, I extend on Stibbard-Hawkes to show that reconsidering the link between cognitive capacity and material culture extends beyond matters of preservation. A reconceptualization of behavioural modernity inclusive of both extant and extinct populations must begin with an honest theoretical separation of biological and behavioural modernity, which requires to critically engage with how we frame the underlying questions.

We present a series of 12 OSL/IRSL dates that revise and complete the chronology of the important Middle (MSA) and Later Stone Age (LSA) site Umbeli Belli in KwaZulu-Natal, South Africa. These dates shift the previous radiometric ages thousands of years older than earlier measurements and play a key role in revising the cultural stratigraphy of KwaZulu-Natal. We also discuss how these dates bring the chrono- and cultural stratigraphy of southern Africa into clearer focus. The Robberg sequence of Umbeli Belli is now firmly dated to 21 ± 2 ka, whereas the preceding Early LSA assemblage dates to ~32 ka, representing one of the earliest dates for this cultural expression in the broader region. The final MSA assemblages from Layer 7 to 9 now date to between 35 ka and 40 ka, overlapping more tightly with comparable assemblages from Sibhudu, Umhlatuzana and other sites. Layer 10, which was previously also assigned to the final MSA, now dates to ~47–54 ka, placing the assemblage within the temporal range of the Late MSA. The new dates provide a good explanation for the clear differences in material culture between Layer 10 and the younger layers. We also present two new ages for the deeper horizons 11b and 12 at Umbeli Belli, dating to 76 ± 9 ka and 80 ± 9 ka, respectively.

Birch tar is the oldest synthetic substance made by early humans. The earliest such artefacts are associated with Neanderthals. According to traditional interpretations, their study allows understanding Neanderthal tool behaviours, skills and cultural evolution. However, recent work has found that birch tar can also be produced with simple processes, or even result from fortuitous accidents. Even though these findings suggest that birch tar per se is not a proxy for cognition, they do not shed light on the process by which Neanderthals produced it, and, therefore, cannot evaluate the implications of that behaviour. Here, we address the question of how tar was made by Neanderthals. Through a comparative chemical analysis of the two exceptional birch tar pieces from Königsaue (Germany) and a large reference birch tar collection made with Stone Age techniques, we found that Neanderthals did not use the simplest method to make tar. Rather, they distilled tar in an intentionally created underground environment that restricted oxygen flow and remained invisible during the process. This degree of complexity is unlikely to have been invented spontaneously. Our results suggest that Neanderthals invented or developed this process based on previous simpler methods and constitute one of the clearest indicators of cumulative cultural evolution in the European Middle Palaeolithic.

The concept of standardization has been applied in archaeological research as a proxy measure for cognitive and behavioral complexity since the late nineteenth century. Here we evaluate these issues in the context of the Middle Stone Age (MSA) examining microlithic technology and laminar blanks and their corresponding core reduction and tool assemblages from the Howiesons Poort (HP) and Sibhudan from Sibhudu (South Africa). We find both standardization and variability among different techno-typological components of these technocomplexes. Similar degrees of standardization characterize the metrics of the bladelet assemblages in the Sibhudan and the backed pieces in the HP, but they remain much more variable than products from craft specialists. We argue for a careful interpretation of standardization in lithic technology taking into account factors like raw material, technological redundancy, site use patterns, functionality and tool biographies. Standardization in lithic tools per se is not an ideal proxy measure for behavioral complexity.

South Africa is arguably one of the most studied regions in Stone Age research. There are, however, considerable differences in research intensity with respect to different regions and time periods. While KwaZulu-Natal is an epicenter for Middle Stone Age (MSA) research, the Late Pleistocene LSA record is largely understudied in this region. Here we present a lithic assemblage from the site Umbeli Belli near Scottburgh dated to 17.8 ± 1.5ka BP. The lithic analysis of the GH 3 assemblages revealed both gradual and abrupt changes within this stratigraphic horizon, indicating relatively short-term changes in material cultural traditions. A comparison with other Robberg sites in the wider surroundings highlights the regional variability of the Robberg techno-complex and indicates potential directions for future research.

Birch tar is one of the oldest adhesives known in human history. Its production has been discussed in the framework of early complex behaviours and sophisticated cognitive capacities. The precise production method used in the Palaeolithic remains unknown today. Arguments for or against specific production pathways have been based on efficiency or process complexity. No studies have addressed the question whether birch tar made with different techniques is more or less performant in terms of its properties. We therefore investigate the adhesive performance of birch tar made with three distinct methods: the open-air condensation method and two variations of underground structures that approximate the double-pot method in aceramic conditions. We use lap-shear testing, a standard mechanical test used for testing the strength of industrial adhesives. Tar made in 1 h with the condensation method has a shear strength similar to, although slightly higher than, tar made underground if the underground process lasts for 20 h. However, tars from shorter underground procedures (5 h) are significantly less strong (by a factor of about 3). These findings have important implications for our understanding of the relationship between the investment required for Palaeolithic birch tar production and the benefits that birch tar represented for early technology. In this regard, the simple and low-investment open-air condensation method provides the best ratio.

»Microlithisation« is generally understood as the proceeding reduction of size of fl int artefacts in the early Holocene. Th is process has been stated continuously in German research, but without considering or discussing possible causes. Four competing hypotheses that have been employed to changes among ethnographically described hunter-gatherer assemblages will be presented in this article. A comparative analysis of these hypotheses yielded that risk is the most important factor for changes in the analyzed hunter-gatherer assemblages. In order to make the hypothesis applicable to archaeological assemblages, the measures for complexity and diversity of toolkits have been adjusted in terms of the Middle Range Th eory. Some Mesolithic assemblages of Northern and Southern Germany have been analyzed against the background of the risk hypothesis. Th e analyses of the archaeological material matched with the predictions of the risk hypothesis-this is why