# 15 ka old evidence of pressure flaking in the Congo basin, Democratic Republic of Congo

Isis Mesfin, Peter R Coutros, Igor Matonda, Jérémie Vosges, Pierre-Jean Texier, Maria-Helena Benjamim, Koen Bostoen

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Isis Mesfin, Peter R Coutros, Igor Matonda, Jérémie Vosges, Pierre-Jean Texier, et al. 15 ka old evidence of pressure flaking in the Congo basin, Democratic Republic of Congo. Journal of Archaeological Science, 2025, 178, 10.1016/j.jas.2025.106219. hal-05083636

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# 15 ka old evidence of pressure flaking in the Congo basin, Democratic Republic of Congo

Isis Mesfin<sup>a,b,*</sup>, Peter R. Coutros<sup>c</sup>, Igor Matonda<sup>d</sup>, Jérémie Vosges<sup>e,f</sup>, Pierre-Jean Texier<sup>g</sup>, Maria-Helena Benjamim<sup>h</sup>, Koen Bostoen<sup>c</sup>

## ARTICLE INFO

**Keywords:**

Pressure technique

Later stone age

Lupemban

Tshitolian

Final pleistocene

Congo basin

Kasai

Technical skills

Scarf-shape retouch

Ballistics

## ABSTRACT

We analyze two technically sophisticated stone points dated between 15,580 and 14,319 cal. BP discovered at the open-air site of Mitshakila, Democratic Republic of Congo, combining diacritic analysis, experimentation, and traditional morphometrics. Diacritical analysis is applied following techno-functional (also called "morpho-structural") and productional approaches. An experimental corpus consisting of pieces produced by both a knapper from northeastern Angola in the 1950s and two lithic specialists aims at improving the identification of techniques. Finally, traditional morphometrics is used to compare Mitshakila points with several shaped points from the Late Pleistocene of sub-Saharan Africa including Tshitolian, Lupemban or Still Bay points among others.

At Mitshakila, we report an early occurrence of the well-mastered use of pressure technique, "scarf-shaped" retouch (also called "ripple-flake" retouch or in French "retouche en écharpe") and proximo-lateral short shoul- ders. Its presence at Mitshakila marks an important technical shift during the Final Pleistocene in the Congo Basin.

## 1. Introduction

Despite nearly 75 years of research, Central Africa's Later Stone Age (LSA) and Middle Stone Age (MSA) are still ill-defined in terms of both chrono-stratigraphy and in technology, with the exception of LSA quartz microlithic technology in north-east Democratic Republic of Congo and Atlantic Central Africa (Cornelissen, 2002; Mesfin et al., 2021). The Lupemban is chronologically extended from the end of the Middle Pleistocene to the Final Pleistocene and is characterized by particular shaping traditions, including core-axes and lanceolates as principal hallmarks (Angue Zogo et al., 2023; Mesfin et al., 2019, 2023; Taylor, 2016). As presently understood, the subsequent LSA techno-typological facies named 'Tshitolian' is distributed across southwestern Central Africa - including the Teke Plateau and the Kasai, Niari, and Middle

Ogooué basins – and extends to the Tumba Lake region in the tropical rainforest of central Democratic Republic of Congo (Fiedler and Preuss, 1985). The Tshitolian supposedly post-dates the Lupemban. However, the record gives the impression of a gradual transition that has forced researchers to establish the “Lupembo-Tshitolian”. In comparison with Lupemban objects, Tshitolian artifacts are smaller, particularly points, core-axes and tranchets. Traditionally, they have been interpreted as ‘miniaturized’ Lupemban tools, but neither morphometric nor techno-logic threshold has been established to distinguish the differences and variability within or between each industry (e.g. Leakey, 1949; Van Moorsel, 1968). The ‘miniaturization phenomena’ would have developed during or immediately following the Late Glacial Maximum (LGM, 23 to 18 ka based on Clark et al., 2009), but the Lupemban and Tshitolian were possibly contemporaneous until the Holocene-Pleistocene

<footnote><sup>a</sup> UMR7194 – Histoire Naturelle de l’Homme Préhistorique MNHN-CNRS-UPVD, Institut de Paléontologie Humaine, 1 rue René Panhard, 75013, Paris, France</footnote>

<footnote><sup>b</sup> Palaeo-Research Institute, University of Johannesburg, Johannesburg, South Africa</footnote>

<footnote><sup>c</sup> UGent Centre for Bantu Studies, Department of Languages and Cultures, Ghent University, Ghent, Belgium</footnote>

<footnote><sup>d</sup> Département des Sciences Historiques, University of Kinshasa, Kinshasa, Congo</footnote>

<footnote><sup>e</sup> Laboratoire Archéorient, Maison de l'Orient et de la Méditerranée – Jean Pouilloux, 7 rue Raulin, Lyon cedex 7, 69365, France</footnote>

<footnote><sup>f</sup> Arkéo Fabrik, 8 rue du Pied des Vignes, 79800, Exoudun, France</footnote>

<footnote><sup>g</sup> CNRS, Aix Marseille University, Minist. Culture, UMR 7269 LAMPEA, 13097, Aix-en-Provence, France</footnote>

<footnote><sup>h</sup> Muséu Nacional de Arqueologia, Benguela, Angola</footnote>

<footnote>* Corresponding author. UMR7194 – Histoire Naturelle de l’Homme Préhistorique MNHN-CNRS-UPVD, Institut de Paléontologie Humaine, 1 rue René Panhard, 75013, Paris, France.</footnote>

<footnote>E-mail address: isis.mesfin@mnhn.fr (I. Mesfin).</footnote>
boundary (Cornelissen, 2002). Distinctive for the Tshitolian are several features such as semi-lunar microliths, micro-tranchets or even tanged points (Breuil, 1943; Cahen and Mortelmans, 1973; Leakey, 1949). However, the significance of changes in stone tool types inside the Congo Basin has thus far not been investigated, neither regarding stone tool manufacturers' skills nor in terms of complexity. In Stone Age studies, *skills* usually refer to a pattern of cognitive and technological evolution in human lineage (e.g. de la Torre, 2004; Lombard and Gärdenfors, 2023; Perreault et al., 2013; Torres and Preysler, 2020). Quantification of *skills* from archeological contexts usually relies on diachronic perspectives, as explored by Muller and colleagues (e.g. Muller et al., 2017; Muller and Clarkson, 2016) who have more recently proposed to evaluate skills based on precision, intricacy and success (Muller et al., 2023). For Final Pleistocene and Holocene Archaeology, it is harder to discuss 'skills' as a pattern of evolution. Consequently, skills evaluation relies on ethnographical data which tend to be abstract and unquantified (e.g. Maloney, 2020; Stout et al., 2002).

We present here two recently discovered points in silicified sandstone (also called "Grès polymorphes" in the regional literature) from Mitshakila, Democratic Republic of Congo, dated between 15,580 and 14,319 cal. BP. As the site is located within the Kwilu-Kasai region (Fig. 1) during the Final Pleistocene, the artifacts fall into the geographical and chronological distribution area of both Tshitolian LSA and Lupemban MSA. Nevertheless, the two artifacts provide the earliest contextualized evidence of pressure flaking in the Congo Basin that could rather point toward a LSA technical development. Indeed, development of pressure flaking implies the development of new skills in stone tools manufactures and the possibility to have highly standardized

stone tool production (Tixier, 1984). In addition, it can also impact foragers mobility thanks to lighter portable equipment (Domanski and Webb, 2007) and also raw material economy (Crabtree, 1972). Pressure and punch technique has already been suggested for the Lupemban but remains sparsely documented (Barham, 2002; Clark, 1963, 2001; Taylor, 2022). Whereas Barham (2002) relates the use of punch technique for blade production in the MSA Siszya Industry that corresponds to the Late Lupemban of Kalambo Falls in Zambia, Taylor (2022) proposes that pressure technique is not a distinctive pattern of MSA technology in Central Africa and that it is rather associated to "Lupembo-Tshitolian" points in the Kasai region. Nevertheless, detailed description of the techniques and artifacts has never been provided.

Despite the difficulty in affiliating Mitshakila to any industry based on two artifacts, Mitshakila offers a new dated occurrence for the use of pressure technique and “scarf-shape” retouch, also called ripple-flake or parallel-transverse retouch or still “retouche en écharpe” in French. This practice is an innovative and complex solution in the shaping *chaîne opératoire* typical of Holocene contexts (e.g. Maiorano et al., 2018; Vaquer et al., 2014) but never described so far in Central Africa. We compensate for the small size of the assemblage with a complete investigation of each artifact, including technological (production), techno-functional (structure), and morphometric analyses. In addition, we apply a comparative analysis incorporating published material from Western, Central, and Southern African Stone Age as well as the experimental record to better understand raw material properties for pressure flaking. Doing so, we question both the relationship between technique and shape in the point production and we discuss the chrono-cultural value of Mitshakila points.

<figure><img src="image_4.png" /><figcaption>Fig. 1. A) Location of D.R. Congo in Central Africa and main rivers, B) location of Mitshakila open air side along the Kwilu River.</figcaption></figure>
## 2. Mitshakila setting and chronology

The open-air site of Mitshakila lays on the eastern bank of the Kwilu River, approximately 40 km northwest of the city of Kikwit, in the Kwilu Province of the Democratic Republic of Congo (Fig. 1). The site was discovered during the first archeological survey of the Kwilu River (965 km long), which resulted in the identification of 150 new sites (Coutros et al., 2023). The site of Mitshakila itself is located within a port associated with a village of the same name ~1 km further inland. Survey of the settlement yielded few dispersed ceramic and lithic finds but no meaningful artifact concentrations (Coutros et al., 2022). However, exposed profiles of a clay mine that exploits the sandy clays of the Kalahari belt in the center of the settlement revealed subsurface deposits. To explore these deposits, three trenches (1–3, respectively 1 × 2m; 1 × 2m and 1×1m) were installed on the northern, eastern, and southern edges respectively of the quarry’s perimeter (Fig. 2-a). Each unit was excavated in arbitrary 10 cm spits due to sediments homogeneity and all sediment passed through a 0.5 cm sieve. The red sandy clay sediments constitutes an arenosol typical from the Final Pleistocene deposits of this region (Crouvi et al., 2010; Muhs et al., 2014). Known locally as “Kalahari Sands”, these deposits originate from both low-energy fluvial and aeolian action and are considered favorable within the research area for preserving site integrity, and stratigraphic position of lithics and charcoals in the Congo Basin (Clark, 1963; Jungnickel et al., 2024).

All three trenches revealed an identical stratigraphy, made up of three distinct strata (Fig. 2-b). The first layer is a highly disturbed A Horizon composed of brownish sandy-loam, organic material, and modern debris. Below is a ~20 cm thick yellowish loamy-sand horizon followed by a final horizon consisting of an extremely compact reddish-orange clay, which yielded the two in situ lithic points. The Mitshakila assemblage is here considered ‘in situ’ as there is no evidence for significant post-depositional disturbance. As many Stone Age deposits throughout the Congo basin have been subject to reworking into so-called “stone-lines”, exhaustive attention was paid to identifying any

signs of disturbance during excavations (Cahen and Moeyersons, 1977; Stoops, 1990). Firstly, all of the materials, including the artifacts and wood charcoal, were recovered from a thin 10 cm lens limited to the northwestern section of the site, quite different from the large-scale stone-lines that stretch over hectares (Mercader et al., 2002). Likewise, the associated dates taken from within this lens provide a tight correspondence. Finally, both the homogeneity of the assemblage’s raw material and the lack of mixed lateritic nodules, cobbles, “gravels”, or other signifiers of a reworked stone-line suggest that the artifacts have not been subject to significant vertical or horizontal movement (David et al., 2004; Mercader et al., 2002). Indeed, the only evidence of post-depositional alteration was a modern pit dug into the southern end of Trench 2. Once the pit was identified, after ~20 cm, it was isolated by a 30 cm border to prevent intermixing of materials (Fig. 2b and c).

Two wood charcoal samples directly associated with the lithic artifacts in the reddish-orange clay horizon (Table 1) were analyzed by the Radiocarbon Dating Lab at the Belgian Royal Institute for Cultural Heritage (KIK-IRPA) and Beta Analytic, and were calibrated at 95.4 % probability using OxCal 4.4 with the SHCal20 calibration curve for the Southern Hemisphere (Hogg et al., 2020; C. B. Ramsey, 2009) (Table 1). The two obtained dates, i.e., 15,580–15,247 cal. BP and 14,957–14,319 cal. BP, are complementary and make Mitshakila one of the rare Final Pleistocene deposits inside the Congo Basin.

<table><caption>**Table 1**
Radiometric dates from Mitshakila Trench 2. Calibration has been conducted on OxCal (Ramsey and OxCal, 2020) using the SHCal20 curve (Hogg et al., 2020).</caption><thead><tr><td>Sample ID</td><td>Depth</td><td>Material</td><td><sup>14</sup>C Age BP</td><td>Calibration σ<sup>2</sup></td></tr></thead><tbody><tr><td>RICH-30973</td><td>38 cm</td><td>Charcoal</td><td>12,921 ± 38</td><td>15,580–15,247 BP</td></tr><tr><td>RICH-30974</td><td>41 cm</td><td>Charcoal</td><td>12,494 ± 37</td><td>14,957–14,319 BP</td></tr></tbody></table>

<figure><img src="image_5.png" /><figcaption>**Fig. 2.** A) sketch of the Trench location, B) natural stratigraphy of Mitshakila Trench 2 and location of the C14 samples (uncalibrated BC), C) Plan view of Mitshakila Trench 2.</figcaption></figure>
# 3. Methods

## 1 The analysis of the stone-tool production and pressure technique identification

Manufacture analysis focuses on patterns which help identify the production mode of lithic artifacts. The "chaîne opératoire" approach, that reconstructs the chronology of operations on the materials (Lemonnier, 1976), consists of grouping the different scars into "sequences" (Lourdeau et al., 2017; Mesfin, 2023) or "phases of production". A "sequence" is defined here as a consistent group of successive removals. Furthermore, diacritical diagrams (Dauvois, 1976; Guibert et al., 2023, p. 35) are then used for establishing the chronology of the scars by grouping them into individual sequences. We have taken into account a detailed chronological reading of the removals by making diacritical diagrams for each Mitshakila point, which aims at highlighting the superposition of removals and the location of impact points to identify manufacturing phases.

In the case of pressure technique, we have relied on the criteria of several authors (Alix et al., 1995; Binder et al., 2012; Crabtree, 1972; Högberg and Lombard, 2016; Mourre et al., 2010) for negative scars, including deep diffuse bulb negative, hackles on the scars, regular ridges, scar usually <10 mm in width, regularity and parallelism of the scars edges, constant or decreasing width of removals, rectitude of the profile and section fineness of the extracted flakes. In addition, distinguishing pressure flaking from punch technique is difficult due to an overlap in scar patterns (Binder et al., 2012; Crassard et al., 2020; Inizan et al., 1995) but also because the punch technique in bifacial technologies is still poorly explored. However, both Geib (2002) and Morin and Matson (2014) provide a strong basis for distinction of punch and pressure techniques on North American points, where serrations would result from pressure flaking and punch technique would result in more sinuous edges.

## 2 The techno-functional analysis

The techno-functional approach (also called "morpho-structural") does not assume any functions for artifacts but proposes mechanical and ergonomic possibilities/limitations based on artifact volumetric and structure patterns. In the case of bifacial points as the ones from Mitshakila, projectile weapon might be completed for other functions, including prestige objects, cutting tools, or as a raw material reserve (Andrefsky, 2006; Maloney, 2020).

The techno-functional analysis aims at understanding the volumetric objectives of the knapping process by comparing production data with volumetric patterns of the final artifact (Forestier, 2020). To do so, the stone tool volume – believed to be functional – is divided into different units ("Unités techno-fonctionnelles" or UTF) related to their functional possibilities based on both edges and surface morphologies (e.g. delineation ruptures, surface organization, cutting edge shape variability, overall outline etc.). The rationale behind this division is both to propose insights into ergonomic patterns (e.g. potential gripping zones) and to study the cutting edges (potential zone of contact with the worked material) – both ergonomics and cutting edges are studied in lithics by other approaches (e.g. Key, 2016; Muller and Clarkson, 2016). There is abundant literature on the application of the techno-functional approach (e.g. Boëda, 2001; Boëda et al., 2021; Capellari et al., 2021; Grimaldi et al., 2020; Pérez-Balarezo et al., 2021; Zhou et al., 2019) and its relevance (Forestier, 2020; Guibert et al., 2023; Weyer et al., 2022). It mainly relies on qualitative variables but also some measurements such as the angle values of a cutting edge or even an edge extension. At Mitshakila, we have identified the main volumetric patterns on both lateral delineation and lithic mass distribution along the longitudinal axis to distinguish three synergetic UTF: "transformative" also called "active" (UTF-a), "hafted" or "prehensile" (UTF-p), and transmitting (UTF-t).

## 3 Morphometrics comparative analysis

### 3.1. Measurements

We conducted a comparative morphometric analysis of both Mitshakila points, MIT1 and MIT2, in order to contextualize the artifacts in a broader sub-Saharan Late Pleistocene record. Morphometrics helps to confirm techno-functional results and to provide insights into ballistic properties and chrono-technical relations within the broader context of African Stone Age points.

We have focused on the mean and standard deviation of the maximal length, maximal width, maximal thickness, mean length/mean width ratio (elongation), mean width/mean thickness ratio (fineness) (Mesfin et al., 2019), and the Tip Cross-Sectional Area of each point (TCSA = 1/2 maximum width x maximum thickness) (Shea, 2006). TCSA neither measures the penetration performance nor assumes a function for artifacts (Coppe et al., 2023; Hutchings, 2016). It is a relevant shape measurement that can be compared with a large spectrum of ethnographic weapons (Lombard, 2021; Lombard et al., 2024; Sisk and Shea, 2011). For the Mitshakila points, apart from traditional measurements based on the techno-functional and production analysis, we have also measured the scar initiation width as it is related to the flaker type and size (Morin and Matson, 2014).

The comparative African Pleistocene dataset is detailed in Table 2 and contains published data from several sites attributed to different periods and regions related to soft hammer or pressure technique bifacial shaping. Finally, the morphometric data have been processed with two distinct Principal Component Analyses (PCA) using R environment (R Core Team, 2018) in addition to bivariate data visualization. Blombos points could not be included due to the incomplete data set, and no statistical significance test could be conducted because we only had access to mean values and standard variation for four of the lithic assemblages. The first PCA includes raw measurements length, width, and thickness whereas the second includes the morphometric indices: TCSA, elongation and fineness. To compute the PCA, we applied a logarithm to the TCSA values due to the natural strong asymmetric, large range of numerical values inherent to the TCSA indices. The division into two PCA was necessary to provide the PCA with fewer variables than individuals.

### 3.2. Regional Central African data set

The MSA and LSA of Central Africa is mainly known through old museum collections – the latter being the richest in shaped tools (e.g. points, foliates, core-axes) (Mesfin et al., 2019, 2020, 2023). Consequently, we added several museum collections from the Kasai region to verify the position of the Mitshakila points among other points recovered in the Kasai River basin. We have selected the assemblages of Balabala (also written MbalaMbala) & Munguanhe 2, Lunda-Norte Province, Angola, affiliated to Lupembo-Tshitolian facies (Clark, 1963, 1967) and currently stored at the *Museu Nacional de Arqueologia de Angola* (Benjamim et al., 2022). Based on Taylor (2016, table 15.2), the Lunda-Norte sites are considered the most reliable series of MSA/LSA artifacts from the Congo basin from a chrono-stratigraphic perspective, despite the scarcity of numeric age (see de Maret et al., 1977 for a list of C14 age in Lunda-Norte). In addition, we have classified and measured each piece from the Balabala & Munguanhe 2 collection stored at the *Museu Nacional de Arqueologia de Angola*. Among these collections, we selected only the measurements of entirely shaped bi-pointed pieces and entirely shaped points with a convex base which all reflect a final phase of production. We have also added metrics from small quartz foliates of the MSA to LSA Maboué V site, Gabon (Mesfin et al., 2021). Finally, as the Tshitolian was interpreted as a direct evolution of Lupemban (e.g. Breuil, 1943; Clark, 1963; Bayle Des Hermens R.de, 1981; Miller, 2001), we have also used a dataset of Lupemban affiliated points from museum
<caption>**Table 2**</caption>

Site name, countries, age & dating methods, cultural affinities selected for the comparison and main raw material and number of stone points. Only complete points have been included.

<table><thead><tr><th>Site</th><th>Country</th><th>Name on plots</th><th>Publication</th><th>Age & method</th><th>Cultural affinities</th><th>Raw material</th><th>Number of points</th></tr></thead><tbody><tr><td>Toumboura III</td><td>Senegal</td><td>TOUM</td><td>Schmid et al. (2022)</td><td>40 ± 3 to 30 ± 3 ka by OSL</td><td>MSA</td><td>Silexite</td><td>7</td></tr><tr><td>Maboué V</td><td>Gabon</td><td>MAB</td><td>Mesfin et al. (2021)</td><td>44.6 and 14.77 cal. BP by C14</td><td>MSA/LSA</td><td>Quartz</td><td>3</td></tr><tr><td>Umhlatuzana</td><td>South Africa</td><td>UMH</td><td>Högberg and Lombard (2016); Lombard et al. (2010)</td><td>41.9 ± 2.6 to 70.5 ± 4.7 ka by OSL</td><td>Still Bay or more recent</td><td>Hornfels, Dolerite, Mudstone, Quartzite, Quartz</td><td>8</td></tr><tr><td>Sibhudu</td><td>South Africa</td><td>SIB-PSB</td><td>Rots et al. (2017)</td><td>72.5 ± 2.0 to 77.3 ± 3.0 ka by OSL</td><td>Pre-Still Bay</td><td>Dolerite, Hornfels, Quartz</td><td>8</td></tr><tr><td>Sibhudu</td><td>South Africa</td><td>SIB</td><td>Lombard et al. (2019); Soriano et al. (2015)</td><td>RSG Layer 70.5 ± 2.4 ka by OSL</td><td>Still Bay</td><td>Quartzite, Dolerite, Hornfels, Sandstone</td><td>31</td></tr><tr><td>Blombos</td><td>South Africa</td><td>BLO</td><td>Mourre et al. (2010); Soriano et al. (2015); Villa et al. (2009)</td><td>M1 phase and top of the M2 phase 77 to 70 ka by OSL</td><td>Still Bay</td><td>Silcrete</td><td>23</td></tr><tr><td>Balabala</td><td>Angola</td><td>BAL</td><td>This publication</td><td>&lt;40 ka techno-typological correlations</td><td>Lupembo-Tshitolian</td><td>Polymorphous sandstone & chert</td><td>6</td></tr><tr><td>Munguanhe 2</td><td>Angola</td><td>MUN</td><td>This publication</td><td>&lt;40 ka techno-typological correlations</td><td>Lupembo-Tshitolian</td><td>Silicified sandstone & chert</td><td>12</td></tr><tr><td>Mitshakila</td><td>D.R. Congo</td><td>MIT</td><td>This publication</td><td>12.9 ka cal. BP</td><td>Unspecified</td><td>Silicified sandstone</td><td>2</td></tr><tr><td>Nzako Ambilo, Nzako Kono, Mpiaka</td><td>R.C.A. & R. Congo</td><td>VAR</td><td>Mesfin et al. (2019, 2023)</td><td>&gt;30 ka techno-typological correlations</td><td>MSA Lupemban affinities</td><td>Silicified sandstone and quartzite</td><td>31</td></tr></tbody></table>

collections: Nzako Kono and Nzako Ambilo from Central African Republic and Mpiaka from Republic of Congo (see Mesfin et al., 2019, 2023 for context and technological description) to observe the differences between the region's typical Lupemban points and the Mitshakila points. The metric data are available in Supplementary Materials 1.

### 3.3. Sub-saharan Stone Age data set

We have selected three datasets of Still Bay points which represent a well-studied high-technicity shaping strategy for points production (Mourre et al., 2010) during the Late Pleistocene in Southern Africa (Archer et al., 2016; Högberg and Lombard, 2016; Soriano et al., 2009; Villa et al., 2009). This phenomenon is considered a short-term cultural event characterized by technological innovations between c. 70 and 73 ka (Jacobs et al., 2008) or even longer time ago (Tribolo et al., 2013). For our comparison, we included three sites:

- Blombos Cave Still Bay points "Stage 3" manufactured by pressure flaking (Villa et al., 2009),

- Sibhudu Still Bay points initially shaped by hard hammer percussion and finished off by soft hammer percussion (Soriano et al., 2015) and complete Pre-Still Bay points characterized by serrations (Rots et al., 2017),

- Umhlatuzana Still Bay and pre-Still Bay shaped points among which serrated ones (Lombard et al., 2010; Sifogeorgaki et al., 2020).

Pressure technique has also recently been reported at Toumboura III, Senegal, during the Upper Pleistocene on silexite raw material (Schmid et al., 2022) showing that this technique may have emerged in various contexts through the Late Pleistocene.

## 4. Results

### 4.1. Production strategy of mitshakila points

We have observed the scars' initiation morphology (including bulb negative), overall scar shape and texture (the ripples), inclination of removals, edge shapes and distal termination of the scars. All the pressure technique patterns were identified on MIT1 and MIT2 removals

(Fig. 3). Because both points are totally shaped by pressure technique, it is highly likely that a preparation phase occurred, or that a specific blank was produced or selected.

As the retouch phase – also called *confection* phase (Lourdeau, 2010) – is so developed and invasive, it is hard to document the initial blank and the preparation phase, even though we observed a proximal small surface that may point toward a flake or thick blade butt.

Three sequences of removals are still visible on MIT1 (Fig. 4A). Sequence 1 is the mesial shaping of the artifact body. Sequence 2a is the distinctive work on the tip with slightly more abrupt removals and the proximal end. On the proximal end (Sequence 2b), the removals present a different orientation (more oblique in comparison with the longitudinal axis) revealing a different gesture in knapping to obtain a tang characterized by two opposite short and broad shoulders.

MIT2 is also characterized by three main shaping sequences (Fig. 5A). Sequence 1 is located from the mesial to proximal part and is characterized by variable removals and a distal series of standardized removals presenting a different flaking axis in comparison to the following sequences. Unlike MIT1, the first sequence shaped the body of the artifact and included the proximal part. Sequence 2 is distal to mesial and is characterized by a bifacial “scarf-shaped” retouch ("retouche en écharpe") also called “ripple-flake” retouch characterized by parallel and oblique – almost entirely crossing – removals and systematically associated to pressure flaking (e.g. Brézillon, 1971; Maiorano et al., 2018; Sestier, 2010; Vaquer et al., 2014). Finally, Sequence 3 is composed of three removals atypical in shape compared to the others scars and represents the last phase of manufacture. We interpret these three disto-lateral removals as a re-shaping event (see Fig. 5).

Finally, both artifacts present slightly serrated edges, which are not intentionally shaped but result from successive removals with deep bulbs explaining their irregularity. On the MIT2 distal point, where the edge was trimmed, serrations are absent.

### 4.2. Techno-functional patterns of mitshakila points

For both MIT1 and MIT2 (Figs. 4B and 5B), we observe a transmitting UTF in the mesial part of the tool corresponding to the longitudinal axis and characterized by a constant morphology visible in the overall profile shape. Both pieces also present similar transforming UTF, characterized
<figure><img src="image_6.png" /><figcaption>Fig. 3. View of MIT1 and MIT2 with zoom view on the scar's patterns.</figcaption></figure>

by thin serrated edges and a very thin pointed tip. However, the proximal part is different, as MIT2 does not display a specific delimited volumetric feature associated to hafting whereas MIT1 has small proximal shoulders. On the contrary, the transition from the distal to proximal extremity is gradual as visible in the width and thickness creating a more convex and broad proximal part.

Both points are characterized by similar volumetric organization with edge angle values from the distal tip to the base at circa 40°–60°. The butt acts as a short proximal platform with an angle value between 85 and 90° marking an important rupture with the thin cutting edge. We believe this small proximal platform might be related to the hafting system. On both pieces the lateral edges have serrations and double beveled cutting edges. The serrations are less pronounced on the distal part where the cutting edge tends to be more rectilinear due to the smaller size of the removals.

### 4.3. Mitshakila points morphological patterns in the broader context of sub-Saharan African pleistocene bifacial points

From a qualitative perspective, the measurement on the scar initiations highlights diverse types of removals between the tip/mesial/proximal parts that concur with the techno-functional approach. The metrical difference between distal and proximal removals can be both due to the force applied in the pressure flaker or to the pressure flaker tip morphology (Morin and Matson, 2014). For example, on MIT1 (Fig. 4C),

in the proximal tang removals are broader than in the mesial part whereas distal retouch removals present usually <2 mm width at the initiation. For MIT1, the metrical data support the division of the removals based on technological observations and reinforce the idea of specific sequences of removals.

For MIT2 (Fig. 5C), we also have noticed an important difference in metrics of scar initiations in the base (larger scars initiation) compared to the tip where scars are shorter and initiation is 6 mm wide. There is an exception for the removals possibly related to re-sharpening (see Sequence 3 - Fig. 5) (see Soriano et al., 2015 for resharpening identification on shaped points). Despite the overall use of pressure technique, we have observed specific types of removals related to the volumetric objectives, e.g. difference of shapes, inclination, and metrics between distal and proximal removals, which corroborates the technological analysis.

From a comparative perspective (Fig. 6), PCA and bivariate analysis show greater proximity of the Mitshakila points with Balabala points and Umhlatuzana points (Table 3).

Based on length, width, and thickness, MIT1 and MIT2 tend to be closer to Still Bay assemblages and Toumboura III points. However, when we observe elongation, the Mitshakila points are closer to Lupembo-Tshitolian and Lupemban points. We also can see that the Central African corpus in general is particularly variable with gradual dispersion of the assemblage on the plot and particularly high standard values (Table 3). This can be explained by the higher metrical values but
<figure><img src="image_7.png" /><figcaption>**Fig. 4.** Diacritical schema of MIT1 including production and techno-functional analyses.</figcaption></figure>

also by the time average of the assemblages due to the chrono-
stratigraphic context of sites.

The axis of PC1 from both computed PCA are dominated respectively
by length and TCSA. This may be explained by the higher values of both
variables but also by an elongation, which is much less variable
compared to fineness. This means that the desire to produce elongated
artifacts is common to all assemblages. Nevertheless, the main vari-
ability occurs in thickness, directly impacting fineness and TCSA and
usually related to both size and technique employed for production.
Both fineness and TCSA also mark the main difference between
Lupemban, Lupembo-Tshitolian and other points.

As a complement, we can note that individually, only three
Lupembo-Tshitolian affiliated points from Balabala present a TCSA sit-
uated between 50 and 34.5 – equivalent with stone arrow tips and
Northern American arrows (Lombard et al., 2024, Fig. 5). On the con-
trary, the Lupemban affiliated points present the highest TCSA value
comparable with spears (Lombard et al., 2024, Fig. 5). At Muguanhe 2,
the minimum TCSA value is 210. This observation highlights the
important morphometric difference between Mitshakila points and
Lupemban or Lupembo-Tshitolian points. Finally, the Mitshakila points’
TCSA reaches ballistic properties comparable to light javelin hunting
weapons (Lombard et al., 2024, Fig. 5).

4.4. Inputs from the experimental record of pressure and punch technique
for point shaping on non-flint raw material

Based on the silcrete pressure-retouched Still Bay points of Blombos
Cave (South Africa) and experimental replicates, it has been argued that
this type of raw material could not be flaked by pressure without heat-
treatment (Mourre et al., 2010) to increase the knapping quality for
pressure or soft-hammering (Delagnes et al., 2016). For Mitshakila,
identifying heat-treatment through any direct analysis is not possible
because silicified sandstone is considerably variable in color and texture
due to different size grains and metamorphism stages (Roberts et al.,
2015). Nevertheless, no double patina could be observed, and the distal
parts of the negative scars are particularly thin and display thin step-like
distal fractures that can indicate a lack of material elasticity. In addition,
we have recorded three different experiments of pressure shaping con-
ducted by three different experienced knappers on polycrystalline or
metamorphic rocks, which demonstrate that heat-treatment is not al-
ways necessary. Nevertheless, a main bias in this study is the use of
metallic flaker by knappers 2 and 3 whereas during the pre-Iron Age
Tshitolian LSA, it is likely that the flaker would have been bone (Rots
et al., 2017), horn (Howell, 1972, p. 120; Morin and Matson, 2014) or
even ochre (Soriano et al., 2009).

Knapper 1 (J.V.), used the pressure technique on Eocene silicified
<figure><img src="image_8.png" /><figcaption>Fig. 5. Diacritical schema of MIT2 including production and techno-functional analyses.</figcaption></figure>

sandstone of central France without heat-treatment (Fig. 7). He obtained scars patterns similar to the ones described by Mourre et al. (2010) and observed here at Mitshakila. He also managed to shape the shoulders using a similar technique. Removals are carried out using a bone-tipped compressor tied to a long handle (ishi stick), after thinning the blank with direct organic soft hammer percussion.

Knapper 2 (P.-J.T.) has also argued that on the silcrete sandstone or silicified sandstone the pressure technique is better applied when a small platform is available, meaning a blank preparation is usually necessary. Indeed, significant force applied during pressure creates particularly visible ridges between scars and a deep bulb negative which is the source of the serrated aspect. The ferruginous silcrete from Bonnieux (Vaucluse, France) presented scars much more visible and particularly linear whereas on the silicified sandstone from Tshitandalukua (Benguela Province, Angola) the scars became less visible in their distal part due to thinness of the distal end (Fig. 8E). None of these raw materials were heated prior to being worked with a copper-tipped flaker.

In Lunda-Norte, between Kwango and Kasai Rivers in Angola, Knapper 3 (Muambumba), experimented punch technique with metal punch and hammer on local silicified sandstones (i.e. *Grès polymorphes*). Muambumba was initially a Chokwe maker of gunflints, i.e. small

squares from local chert nodules (Martins, 1959). These gunflints sha-
ped by punch technique and retouched by pressure reach impressively
thin dimensions proving the knapper's high technical skills (Fig. 9a–d).
J.D. Clark and V. Martins worked with Muambumba in the late
1950s/early 1960s to better characterize Lupemban and Tshitolian
knapping techniques. The video is a part of the experiment made by
Muambumba and is currently stored by the Diamang Digital Project of
Coimbra University, Portugal (https://www.diamangdigital.net/). Even
if Knapper 3 did not analyze the archaeological material before the
experiment and did not train, the recording has allowed us to observe his
punch technique to compare Lupemban and Tshitolian tools from the
museum collection.

The material worked by Muambumba and the one used in the Lunda-
Norte Lupemban and Tshitolian assemblages (Clark, 1963) are from the
same geological formation as Mitshakila (i.e. the *Grès polymorphes*). The
artifacts are currently stored under the inventory number 292/60 at the
Dundo Museum, Angola, where the authors (I.M. and M.H.B.) studied
them in 2021. Experimental points display very thin regularly serrated
edges but scars are much shorter and are intentional. To accomplish this,
the knapper maintains the blank between his heels. With the left hand,
he holds the punch very close to the striking platform's edge with an
<figure><img src="image_9.png" /><figcaption>**Fig. 6.** Plots of the raw measurements and morphometric indices of Mitshakila (MIT), Balabala (BAL), Sibhudu (SIB), Sibhudu Pre-Still Bay (SIB-PSB), Umhlatuzana (UMH), Toumboura III (TOUM), Maboué V (MAB), Munguanhe 2 (MUN) and Lupemban points from various museum collections (VAR). See Tables 2 and 3.</figcaption></figure>

<caption>**Table 3**</caption>

Mean values and standard variation (s.d.) of length (L), width (W), thickness (T), tip cross-sectional area (TCSA), elongation (length/width) and fineness (width/ thickness) used for the comparative study. In millimeters. For Mitshakila, each point corresponds to one raw.

<table><thead><tr><th>Site</th><th>Mean L</th><th>s.d. L</th><th>Mean W</th><th>s.d. W</th><th>Mean T</th><th>s.d. T</th><th>mean TCSA</th><th>s.d. TCSA</th><th>mean Elongation</th><th>s.d. Elongation</th><th>mean Fineness</th><th>s.d. Fineness</th></tr></thead><tbody><tr><td>Toumboura III</td><td>57.90</td><td>25.50</td><td>24.70</td><td>13.30</td><td>10.10</td><td>6.00</td><td>124.73</td><td>-</td><td>2.34</td><td>-</td><td>2.44</td><td>-</td></tr><tr><td>Maboué V</td><td>75.66</td><td>9.11</td><td>29.33</td><td>9.55</td><td>18.00</td><td>6.67</td><td>263.97</td><td>161.44</td><td>2.58</td><td>0.82</td><td>1.63</td><td>0.13</td></tr><tr><td>Umhlatuzana</td><td>53.90</td><td>12.20</td><td>18.70</td><td>4.90</td><td>8.70</td><td>1.40</td><td>82.70</td><td>34.20</td><td>2.80</td><td>0.10</td><td>2.10</td><td>0.20</td></tr><tr><td>Sibhudu-PSB</td><td>44.75</td><td>12.27</td><td>26.37</td><td>8.17</td><td>8.37</td><td>1.30</td><td>111.37</td><td>37.05</td><td>1.77</td><td>0.45</td><td>3.19</td><td>0.98</td></tr><tr><td>Sibhudu</td><td>52.60</td><td>12.50</td><td>30.30</td><td>5.80</td><td>8.70</td><td>2.20</td><td>131.80</td><td>-</td><td>1.90</td><td>0.30</td><td>3.60</td><td>0.80</td></tr><tr><td>Blombos</td><td>55.00</td><td>12.60</td><td>-</td><td>-</td><td>8.30</td><td>2.20</td><td>99.40</td><td>48.50</td><td>-</td><td>-</td><td>2.80</td><td>0.40</td></tr><tr><td>Balabala</td><td>89.16</td><td>44.49</td><td>26.33</td><td>6.80</td><td>8.16</td><td>4.95</td><td>120.33</td><td>94.11</td><td>3.24</td><td>0.89</td><td>4.05</td><td>1.97</td></tr><tr><td>Munguanhe 2</td><td>124.58</td><td>22.81</td><td>40.33</td><td>8.10</td><td>22.25</td><td>5.19</td><td>466.37</td><td>196.99</td><td>3.16</td><td>0.69</td><td>1.83</td><td>0.19</td></tr><tr><td>Mitshakila n°1</td><td>66.00</td><td>-</td><td>25.00</td><td>-</td><td>5.00</td><td>-</td><td>62.50</td><td>-</td><td>2.64</td><td>-</td><td>5.00</td><td>-</td></tr><tr><td>Mitshakila n°2</td><td>67.00</td><td>-</td><td>23.00</td><td>-</td><td>4.00</td><td>-</td><td>46.00</td><td>-</td><td>2.91</td><td>-</td><td>5.75</td><td>-</td></tr><tr><td>Various</td><td>138.77</td><td>45.20</td><td>53.00</td><td>12.92</td><td>31.09</td><td>9.29</td><td>872.37</td><td>423.96</td><td>2.58</td><td>0.47</td><td>1.75</td><td>0.31</td></tr></tbody></table>

oblique orientation. With the right hand, he has another metallic bar and proceeds to tangential percussion. This proves the possibility to use such techniques on untreated silicified sandstone from Central Africa.

## 5. Discussion and conclusion

Recent excavations at Mitshakila have yielded Terminal Pleistocene deposits containing examples of pressure flaked points based on which we have presented here the earliest described and contextualized evidence of pressure flaking inside the Congo Basin. The combination of technological, techno-functional, morphometric and experimental data provides a complete perspective of the Mitshakila points and exemplifies the use of morphometrics in qualitative technological studies. The results point toward a mastered and adapted technical solution for a specific morphological objective that is related to fineness.

The 3rd experiment we presented argues that the blank immobility is not an argument to exclude punch technique for points

production. On the contrary, the serrated edges and linearity of the edges (Geib, 2002; Morin and Matson, 2014) along with the "scarf-shape" retouch argue for the use of pressure technique at Mitshakila. Beyond the pressure technique, the particularly thin morphology, the use of "scarf-shape" retouch (Maiorano et al., 2018), also called "ripple-flake" retouch (Vaquer et al., 2014), the production of short shoulders, the presence of a short tang, the mastery of several types of removals, and the high productional, techno-functional and morphometric resemblances between both points point towards a specialized technical knowledge applied on silicified sandstone probably without prior heat-treatment. Functionally, Mitshakila points have the smallest TCSA in our entire Stone Age comparative corpus and have particularly thin, continuous, and slightly serrated edges. They could have belonged to complex projectile weapons with a high penetration potential during hunting.

At Mitshakila, despite the absence of learning context, social, cultural and functional value of the artifacts, we consider the two points to
<figure><img src="image_10.png" /><figcaption>Fig. 7. Points shaped by pressure on central France polymorphous sandstone by J.V.</figcaption></figure>

<figure><img src="image_11.png" /><figcaption>Fig. 8. a to c: photos showing the motion, gesture of pressure-flaking on Bonnieux ferruginous silcrete; (a) shows the preparation of a narrow lateral platform with soft stone hammer prior pressure flaking; (d) is a close view of the pressure retouched area on the Bagneux ferruginous silcrete; (e) is a close view of the pressure retouched area on the Tshitandalukua polymorphous sandstone.</figcaption></figure>

be the product of highly skilled knappers as the diacritical and morphometric analysis show precision, intricacy and success (Muller et al., 2023). In fact, the two Mitshakila points are very different from both Lupemban and Lupembo-Tshitolian Central African artifacts despite similar raw material and geographical proximity. This could be a reflection of the change perceived by previous typologists between the Lupemban and the Tshitolian (e.g. Breuil, 1943; Leakey, 1949; Van Moorsel, 1968) which could be related to a continuity of shaping

strategies in Central Africa. Even though shaping could have been perpetuated over long periods inside the Congo Basin, the morphometric and technological aspects of Mitshakila points indicate a shift in tool functionalities and shaping *chaîne opératoires* and technicity during the Final Pleistocene.

From a techno-morphological perspective, Mitshakila points rather fall into the morphometric variability of Still Bay points used in this study, which were produced more than 50 ka years before in South
<figure><img src="image_12.png" /><figcaption>**Fig. 9.** a, b, c and d: screenshots from the film of J.D. Clark and V. Martins of Muambumba flint-gun maker using punch technique followed by pressure retouch with a metallic blade on regional silicified sandstone. The photo (d) shows Muambumba replicating a Lupemban point with punch technique. In pink is the blank being worked. Photos from Diamang Digital – University of Coimbra, Portugal. On the right, artifacts from 292/60 collection from Dundo Museum, Angola. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)</figcaption></figure>

Africa. As at Toumboura III (Schmid et al., 2022), we possibly deal here with a technical convergence indicating that these complex techniques were invented repeatedly during the Late Pleistocene.

To conclude, the discovery of well-mastered pressure shaping and the scarf-shape retouch for producing exceptionally fine points in the African Late Pleistocene context strongly suggest that earlier evidence could be still discovered in the region. The morphometric differences between these artifacts and those from museum collections further raise questions about technological diversity within Central African Final Pleistocene assemblages. *In fine*, the discovery of pressure shaping of points dating back 15,000 years in Central Africa provides critical evidence of the technological diversification within the Later Stone Age, highlighting regional innovations that emphasize the adaptive complexity of past human populations in diverse environmental contexts since the Final Pleistocene.

**CRediT authorship contribution statement**

**Isis Mesfin:** Writing – original draft, Visualization, Methodology, Formal analysis, Conceptualization. **Peter R. Coutros:** Writing – review & editing, Writing – original draft, Project administration, Investigation, Funding acquisition. **Igor Matonda:** Writing – review & editing, Supervision, Project administration, Investigation, Funding acquisition. **Jérémie Vosges:** Writing – review & editing, Visualization, Methodology. **Pierre-Jean Texier:** Writing – review & editing, Visualization, Methodology, Formal analysis. **Maria-Helena Benjamim:** Writing – review & editing, Supervision, Project administration, Data curation. **Koen Bostoen:** Writing – review & editing, Supervision, Project administration, Investigation, Funding acquisition, Data curation.

**Data availability statement**

Metrical data from Central African Republic, Gabon, Angola and D.R. Congo are available in the Supplementary Materials 1. More data is available upon request. For South African and Senegalese record, sharing is not applicable because no new data were generated.

**Declaration of competing interest**

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Koen Bostoen reports financial support, equipment, drugs, or supplies, and travel were provided by European Research Council. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

**Acknowledgements**

The site was identified during the 2021 BantuFirst river reconnaissance, funded by the European Research Council (ERC Consolidator's Grant no. 724275) under the European Union's Horizon 2020 research and innovation program. Authors are grateful to the Ministry of Culture of the Democratic Republic of Congo, to the Institut des Musées Nationaux du Congo and to the Museum of Dundo in Angola. Authors are grateful to Viola Schmid and the two anonymous reviewers for her comments that really improved the paper.

**Appendix A. Supplementary data**

Supplementary data to this article can be found online at https://doi.org/10.1016/j.jas.2025.106219.

**References**

Alix, P., Pelegrin, J., Deloge, H., 1995. Un débitage original de lamelles par pression au Magdalénien du Rocher-de-la-Caille (Loire, France). https://doi.org/10.3406/pal.1995.1214.

Andrefsky, W., 2006. Experimental and archaeological verification of an index of retouch for hafted bifaces. Am. Antiq. 71 (4), 743–757. https://doi.org/10.2307/40035887.

Angue Zogo, M.-J., Mesfin, I.I., Pleurdeau, D., de Saulieu, G., 2023. Le core-axe, un outil tropical à redéfinir: Nouvelles données des collections Middle Stone Age de Nzako, République centrafricaine. L'Anthropologie, Préhistoire de l'Afrique de l'Ouest et du Centre.

Archer, W., Pop, C.M., Gunz, P., McPherron, S.P., 2016. What is Still Bay? Human biogeography and bifacial point variability. J. Hum. Evol. 97, 58–72. https://doi.org/10.1016/j.jhevol.2016.05.007.
Barham, L., 2002. Backed tools in Middle Pleistocene central Africa and their evolutionary significance. J. Hum. Evol. 43 (5), 585-603. https://doi.org/10.1006/jhev.2002.0597

Bayle Des Hermens (R.de), 1981. Note typologique sur le Tshitolien du Congo, in *Préhistoire Africaine: mélanges offerts au Doyen Lionel Balout*. A.D.P.F, Paris, pp. 341-348.

Benjamín, M.H., Mesfin, I.I., Raul, K., Benjamin, E., 2022. As "pedras lascadas" do Museu Nacional de Arqueologia de Benguela. Jornal Da Cultura - Artes & Letras.

Binder, D., Collina, C., Guilbert, R., Perrin, T., Garcia-Puchol, O., 2012. Pressure-knapping blade production in the north-western mediterranean region during the seventh millennium cal B.C. In: Desrosiers, P.M. (Ed.), The Emergence of Pressure Blade Making: from Origin to Modern Experimentation. Springer US, pp. 199-217. https://doi.org/10.1007/978-1-4614-2003-3-7

Boëda, E., 2001. Détermination des unités techno-fonctionnelles de pièces bifaciales provenant de la couche acheuléenne C'3 base du site de Barbas I. Les Industries à Outils Bifaciaux Du Paléolithique Moyen d'Europe Occidentale 98, 51e75.

Boëda, E., Ramos, M., Pérez, A., Hatté, C., Lahaye, C., Pino, M., Hérisson, D., Clemente-Conte, I., Fontugne, M., Guérin, G., Villagran, X., Santos, J.C., Costa, L., Germond, L., Ahmed-Delacroix, N.E., Costa, A.D., Borges, C., Hoeltz, S., Felice, G., et al., 2021. 24.0 kyr cal BP stone artefact from Vale da Pedra Furada, Piauí, Brazil: Techno-functional analysis. PLoS One 16 (3), e0247965. https://doi.org/10.1371/journal.pone.0247965

Breuil, H., 1943. Le Paléolithique au Congo Belge d'après les recherches du Docteur Cabu. Trans. Roy. Soc. S. Afr. 20 (Part II), 143-174.

Brézillon, M.N., 1971. La dénomination des objets de pierre taillée: Matériaux pour un vocabulaire des préhistoriens de langue française. Centre national de la recherche scientifique.

Cahen, D., Moeyersons, J., 1977. Subsurface movements of stone artefacts and their implications for the prehistory of Central Africa. Nature 266 (5605), 812-815. https://doi.org/10.1038/266812a0

Cahen, D., Mortelmans, G., 1973. Un site Tshitolien sur le Plateau des Bateke (République du Zaïre). Musée royal d'l'Afrique centrale.

Capellari, F., Grégoire, S., de Lumley, H., 2021. Lower Palaeolithic Core-Flake Industries in Western Europe: Techno-Functional Study of Layer «L» of Caune de l'Arago Cave (Tautavel, France). Journal of Paleolithic Archaeology 4 (3), 18. https://doi.org/10.1007/s41982-021-00092-7

Clark, J.D., 1963. Prehistoric cultures of northeast Angola and their significance in tropical Africa, Diamang, publicações culturais, 62, Lisboa, p. 222.

Clark, J.D., 1967. Atlas of African Prehistory. University of Chicago Press.

Clark, J.D., 2001. Kalambo Falls Prehistoric Site, III: the Earlier Cultures: Middle and Earlier Stone Age. Cambridge University Press, Cambridge.

Clark, P.U., Dyke, A.S., Shakun, J.D., Carlson, A.E., Clark, J., Wohlfarth, B., Mitrovica, J. X., Hostetler, S.W., McCabe, A.M., 2009. The last glacial maximum. Science 325 (5941), 710-714.

Coppe, J., Taipale, N., Rot, V., 2023. Terminal ballistic analysis of impact fractures reveals the use of spearthrower 31 ky ago at Maisières-Canal, Belgium. Sci. Rep. 13 (1), 18305. https://doi.org/10.1038/s41598-023-45554-w

Cornelissen, E., 2002. Human responses to changing environments in Central Africa between 40,000 and 12,000 BP. J. World PreHistory 16 (3), 197-235. https://doi.org/10.1023/A:1020949501304.

Coutros, P., Matonda Sakala, I., Mabuaka Duki, A., Nkanu Tsatsa, I., Bostoen, K., 2022. The BantuFirst Project: 2021 fieldwork report on the kwilu-kasai-kamtsha-loange river reconnaissance mission. Nyame Akuma 97, 14-21.

Coutros, P., Matonda Sakala, I., Mabuaka Duki, A., Nkanu Tsatsa, I., Bostoen, K., 2023. The BantuFirst Project: 2022 Fieldwork Report on the Kwilu-Kasai River Reconnaissance and Mashita Mbanca Excavations (Democratic Republic of the Congo), vol. 99. Nyame Akuma.

Crabtree, D.E., 1972. An introduction to flintworking. Swanson & Butler).

Grassard, R., Charpentier, V., McCormiston, J., Vosges, J., Bouzid, S., Petraglia, M.D., 2020. Fluted-point technology in Neolithic Arabia: an independent invention far from the Americas. PLoS One 15 (8), e0236314. https://doi.org/10.1371/journal.pone.0236314

Crouvi, O., Amit, R., Enzel, Y., Gillespie, A.R., 2010. Active sand and sand and the formation of desert loess. Quat. Sci. Rev. 29 (17), 2087-2098. https://doi.org/10.1016/j.quascirev.2010.04.026

Dauvois, M., 1976. Precis de Dessin Dynamique et Structural des Industries Lithiques Préhistoriques. Fanlac, Périgueux, 263. Dynamic and Structural Drawing Precise of Prehistoric Lithic Industries.

Brown, David J., McSweeney, Kevin, Helmke, Philip A., 2004. Statistical, geochemical, and morphological analyses of stone line formation in Uganda. Geomorphology 62, 3-4. https://doi.org/10.1016/j.geomorph.2004.03.002, 217-237, ISSN 0169-555X.

de la Torre, I., 2004. Omo revisited: evaluating the technological skills of pliocene hominins. Curr. Anthropol. 45 (4), 439-465. https://doi.org/10.1086/422079

de Maret, P., Van Noten, F., Cahen, D., 1977. Radiocarbon dates from west central Africa: a synthesis. J. Afr. Hist. 18 (4), 481-505.

Delagnes, A., Schmidt, P., Douze, K., Wurz, S., Bellot-Gurlet, L., Conard, N.J., Nickel, K. G., Niekerk, K. L. van, Henshilwood, C.S., 2016. Early evidence for the extensive heat treatment of silcrete in the howiesons poort at klipdrift shelter (layer PBD, 65 ka), South Africa. PLoS One 11 (10), e0163874. https://doi.org/10.1371/journal.pone.0163874

Domanski, M., Webb, J., 2007. A review of heat treatment research. Lithic Technol. 32 (2), 153-194. https://doi.org/10.1080/01977261.2007.11721052

Fiedler, L., Preuss, J., 1985. Stone tools from the Inner Zaïre Basin (Région de l'Equateur, Zaïre). Afr. Archaeol. Rev. 3 (1), 179-187.

Forestier, H., 2020. La pierre et son ombre. *Epistémologie de la Préhistoire* (L'Harmattan).

Geib, P., 2002. Basketmaker II horn flaking tools and dart point production: technological change at the agricultural transition. In: Traditions, Transitions and Technologies, Themes in Southwestern Archeology. University Press of Colorado, pp. 272-306.

Geib, P., 2002b. Basketmaker II horn flaking tools and dart point production: technological change at the agricultural transition. In: Schlanger, S. (Ed.), Traditions, Transitions, and Technologies: Themes in Southwest Archaeology. University Press of Colorado, pp. 272-306. https://www.academia.edu/9596691/Basketmaker_II_Horn_Flaking_Tools_and_Dart_Point_Production_Technological_Change_at_the_Agricultural_Transition

Grimaldi, S., Santaniello, F., Angelucci, D.E., Bruni, L., Parenti, F., 2020. A techno-functional interpretation of the lithic assemblage from fontana nanuccio (agnagni, Central Italy): an insight into a MIS 11 human behaviour. Journal of Paleolithic Archaeology. https://doi.org/10.1007/s41982-020-00064-3

Guibert, J., Pérez-Balarezo, A., Forestier, H., 2023. Signs of prehistory. A Peircean semiotic approach to lithics. Archaeol. Dialogues 1-19. https://doi.org/10.1017/S138020382300003X

Högberg, A., Lombard, M., 2016. Indications of pressure flaking more than 70 thousand years ago at Umhlatuzana rock shelter. S. Afr. Archaeol. Bull. 71 (203), 53-59.

Hogg, A., Heaton, T., Hua, Q., Palmer, J., Turney, C., Southon, J., Bayliss, A., Blackwell, P., Boswijk, G., Bronk Ramsey, C., Petchey, F., Reimer, P., Wacker, L., 2020. SHCal20 Southern Hemisphere calibration, 0-55,000 years cal BP. Radiocarbon 62.

Howell, F.C., 1972. *L'Homme Préhistorique*. TIME LIFE. Time INC, Le monde vivant, p. 200.

Hutchings, W.K., 2016. When is a point a projectile? Morphology, impact fractures, scientific rigor, and the limits of inference. In: Iovita, R., Sano, K. (Eds.), Multidisciplinary Approaches to the Study of Stone Age Weaponry. Springer, Netherlands, pp. 3-12. https://doi.org/10.1007/978-94-017-7602-8-1

Inizan, M.-L., Reduron, M., Roche, H., Tixier, J., 1995. Technologie de la pierre taillée suivi par un vocabulaire multilingue allemand, anglais, arabe, espagnol, français, grec, italien, portugues, Tome 4. CNRS (C.R.E.P.). C.R.E.P.

Jacobs, Z., Roberts, R.G., Galbraith, R.F., Deacon, H.J., Grün, R., Mackay, A., Mitchell, P., Vogelsang, R., Wadley, L., 2008. Ages for the Middle stone age of southern Africa: implications for human behavior and dispersal. Science 322 (5902), 733-735. https://doi.org/10.1126/science.1162219

Jungnickel, K.V.M., Seidensticker, D., Hubau, W., Mees, F., Cornelissen, E., Bostoen, K., 2024. The Late Pleistocene and Holocene chronocultural and anthracological open-air sequence from Mukila (DRC). Quat. Sci. Rev. 337, 108752. https://doi.org/10.1016/j.quascirev.2024.108752

Mercader, Julio, Martí, Raquel, Luis Martínez, José, Brooks, Alison, 2002. The nature of 'stone-lines' in the African Quaternary record: archaeological resolution at the rainforest site of Mosumu, Equatorial Guinea. Quaternary International 89 (1), 71-96. https://doi.org/10.1016/S1040-6182(01)00082-9. ISSN 1040-6182.

Key, A.J.M., 2016. Integrating mechanical and ergonomic research within functional and morphological analyses of lithic cutting technology: key principles and future experimental directions. Ethnoarchaeology 8 (1), 69-89. https://doi.org/10.1080/19442890.2016.1150626.

Leakey, L.S.B., 1949. Tentative Study of the Pleistocene Climatic Changes and Stone-Age Culture Sequence in North-Eastern Angola, vol. 4. Museu do Dundo.

Lemonnier, P., 1976. La description des chaînes opératoires: Contribution à l'analyse des systèmes techniques. Tech. Cult. 1 (1), 100-151.

Lombard, M., 2021. Variation in hunting weaponry for more than 300,000 years: a tip cross-sectional area study of Middle Stone Age points from southern Africa. Quat. Sci. Rev. 264, 107021. https://doi.org/10.1016/j.quascirev.2021.107021

Lombard, M., Gärdenfors, P., 2023. Causal cognition and theory of mind in evolutionary cognitive Archaeology. Biological Theory 18 (4), 234-252. https://doi.org/10.1007/s13752-020-00372-5

Lombard, M., Högberg, A., Wadley, L., 2019. Temporal perspectives on still Bay point production at sibudu Cave, KwaZulu-natal, in the context of southern Africa. Azania 54 (2), 141-176. https://doi.org/10.1080/0067270X.2019.1619280.

Lombard, M., Lotter, M.G., Caruana, M.V., 2024. The tip cross-sectional area (TCSA) method strengthened and constrained with ethno-historical material from sub-saharan Africa. J. Archaeol. Method Theor 31 (1), 26-50. https://doi.org/10.1007/s10816-022-09595-1

Lombard, M., Wadley, L., Jacobs, Z., Mohapi, M., Roberts, R.G., 2010. Still Bay and serrated points from Umhlatuzana rock shelter, kwazulu-natal, South Africa. J. Archaeol. Sci. 37 (7), 1773-1784. https://doi.org/10.1016/j.jas.2010.02.015

Lourdeau, A., 2010. Le technocomplexe Itaparica—Définition techno-fonctionnelles des industries à pièces façonnées unifacialement à une face plane dans le centre et le nord-est du Brésil pendant la transition Pleistocène-Holocène et Holocène ancien. Paris 10.

Lourdeau, A., Carbonera, M., Hoeltz, S., Santos, M.C.P., Lucas, L. de O. e, Costa, A.D., Viana, S., 2017. Debitagem laminar no Sul do Brasil: habemus nucleos. Journal of Lithic Studies 4 (3), 127-143. https://doi.org/10.2218/jls.v4i3.2530

Maiorano, M.P., Marchand, G., Vosges, J., Berger, J.-F., Borgi, F., Charpentier, V., 2018. The neolithic of sharbithat (dhofar, sultanate of Oman): typological, technological, and experimental approaches. Proceedings of the Seminar for Arabian Studies 48, 219-233.

Maloney, T.R., 2020. Kimberley points of Western Australia: pressure flaking, projections and prestige. Journal of Lithic Studies 7 (1). https://doi.org/10.2218/jls.2968. Article 1.

Martins, V., 1959. Reminiscencias da ultima Idade da Pedra na Historia tradicional e oral dos povos da Lunda. Museu do Dundo; Archives du Muséum du Dundo, Angola 22 [Activity Report].
Mesfin, I., 2023. The knapping of quartz crystals during the later stone age at Matupi Cave, Ituri Province, democratic republic of Congo. Lithic Technol. https://doi.org/10.1080/01977261.2023.2188342.

Mesfin, I., Leplongeon, A., Borel, A., Pleurdeau, D., 2019. Using morphometrics to reappraise old collections: the study case of Congo Basin Middle Stone Age bifacial industry. Journal of Lithic Studies 7 (1). https://doi.org/10.2218/jls.4329.

Mesfin, I., Leplongeon, A., Cabanés, J., Angue Zogo, M.-J., Pleurdeau, D., 2023. New technological considerations on some Lupemban museum collections from the Congo Basin. L'Anthropologie, 103190. https://doi.org/10.1016/j.anthro.2023.103190.

Mesfin, I., Oslysis, R., Forestier, H., 2021. Technological analysis of the quartz industry of Maboué 5 – layer 3 (Lopé national park, Gabon): implications for the late stone age emergence in western central Africa. J. Archaeol. Sci.: Reports 39, 103130. https://doi.org/10.1016/j.jasrep.2021.103130.

Mesfin, I., Pleurdeau, D., Angue Zogo, M.-J., Leplongeon, A., 2020. Le Middle Stone Age dans le Bassin du Congo: Un regard historiographique. J. des Africanistes vol 90 (2), 88–120. https://doi.org/10.4000/africanistes.9903.

Miller, S.F., 2001. Tshitolian. In: Peregrine, P.N., Ember, M. (Eds.), Encyclopedia of Prehistory: Volume 1: Africa. Springer US, pp. 278–286. https://doi.org/10.1007/978-1-4615-1193-9_24.

Morin, J., Matson, R.G., 2014. The scars that never heal: identifying projectile point manufacturing techniques from flake scars: a case from cedar mesa, Utah. KIVA 80 (2), 137–167. https://doi.org/10.1179/0023194015Z.00000000042.

Mourre, V., Villa, P., Henshilwood, C.S., 2010. Early use of pressure flaking on lithic artifacts at Blombos Cave, South Africa. Science 330 (6004), 659–662. https://doi.org/10.1126/science.1195550.

Muhs, D., Cattle, S., Crouvi, O., Rousseau, D.-D., Sun, J., Zárate, M., 2014. Chapter 16 Loess Records, pp. 411–441. https://doi.org/10.1007/978-94-017-8978-3_16.

Muller, A., Clarkson, C., 2016. Identifying major transitions in the evolution of lithic cutting edge production rates. PLoS One 11 (12), e0167244.

Muller, A., Clarkson, C., Shipton, C., 2017. Measuring behavioural and cognitive complexity in lithic technology throughout human evolution. J. Anthropol. Archaeol. 48, 166–180.

Muller, A., Shipton, C., Clarkson, C., 2023. The proceduralization of hominin knapping skill: memorizing different lithic technologies. Camb. Archaeol. J. 1–18. https://doi.org/10.1017/S0959774323000070.

Pérez-Balarezo, A., Navarro-Harris, X., Boëda, E., Pino, M., 2021. Beyond the mighty projectile point: techno-functional study in a late Pleistocene artifact, pilauco site, osorno, northwestern Chilean patagonia. Lithic Technol. 0 (0), 1–23. https://doi.org/10.1080/01977261.2021.1958133.

Perreault, C., Brantingham, P.J., Kuhn, S.L., Wurz, S., Gao, X., 2013. Measuring the complexity of lithic technology. Curr. Anthropol. 54 (S8), S397–S406. https://doi.org/10.1086/673264.

R Core Team, 2018. R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienna, Austria. http://www.R-project.org.

Ramsey, B., OxCAL, C., 2020. 4.3 Manual.

Ramsey, C.B., 2009. Bayesian analysis of radiocarbon dates. Radiocarbon 51 (1), 337–360.

Roberts, E., Jelsma, H.A., Hegna, T., 2015. Mesozoic sedimentary cover sequences of the Congo basin in the Kasai region, democratic republic of Congo. In: Geology and Resource Potential of the Congo Basin. Springer, Berlin, Heidelberg, pp. 163–191. https://doi.org/10.1007/978-3-642-29482-2_9.

Rots, V., Lentfer, C., Schmid, V.C., Porraz, G., Conard, N.J., 2017. Pressure flaking to serrate bifacial points for the hunt during the MIS5 at Sibudu Cave (South Africa). PLoS One 12 (4), e0175151. https://doi.org/10.1371/journal.pone.0175151.

Schmid, V.C., Douze, K., Tribolo, C., Martinez, M.L., Rasse, M., Lespez, L., Lebrun, B., Hérisson, D., Ndiaye, M., Huysecom, E., 2022. Middle stone age bifacial technology and pressure flaking at the MIS 3 site of Toumboura III, eastern Senegal. Afr. Archaeol. Rev. 39 (1), 1–33. https://doi.org/10.1007/s10437-021-09463-5.

Sestier, C., 2010. Méthode d'étude de la retouche des outils sur lames de silex pressigniennes. ArcheoSciences. Revue d'archéométrie 34. https://doi.org/10.4000/archosciences.2576. Article 34.

Shea, J.J., 2006. The origins of lithic projectile point technology: evidence from Africa, the Levant, and Europe. J. Archaeol. Sci. 33 (6), 823–846. https://doi.org/10.1016/j.jas.2005.10.015.

Sifogeorgaki, I., Klinkenberg, V., Esteban, I., Murungi, M., Carr, A.S., van den Brink, V.B., Dusseldorp, G.L., 2020. New excavations at Umhlatuzana rockshelter, KwaZulu-Natal, South Africa: a stratigraphic and taphonomic evaluation. Afr. Archaeol. Rev. 37 (4), 551–578. https://doi.org/10.1007/s10437-020-09410-w.

Sisk, M.L., Shea, J.J., 2011. The African origin of complex projectile technology: an analysis using tip cross-sectional area and perimeter. Int. J. Evol. Biol. 2011, e968012. https://doi.org/10.4061/2011/968012.

Soriano, S., Villa, P., Delagnes, A., Degano, I., Pollarolo, L., Lucejko, J.J., Henshilwood, C., Wadley, L., 2015. The still Bay and howiesons poort at sibudu and Blombos: understanding Middle stone age technologies. PLoS One 10 (7), e0131127. https://doi.org/10.1371/journal.pone.0131127.

Soriano, S., Villa, P., Wadley, L., 2009. Ochre for the toolmaker: shaping the still Bay points at sibudu (KwaZulu-Natal, South Africa). J. Afr. Archaeol. 7 (1), 41–54.

Stoops, G., 1990. The stone-line as a key to former surface processes: an example from the lower Zaïre. In: Paysages quaternaires de l'Afrique centrale atlantique.

Stout, D., Bril, B., Roux, V., DeBeaune, S., Gowlett, J.A.J., Keller, C., Wynn, T., Stout, D., 2002. Skill and cognition in stone tool production: an ethnographic case study from Irian Jaya. Curr. Anthropol. 43 (5), 693–722.

Taylor, N., 2016. Across rainforests and woodlands: a systematic reappraisal of the lupemban Middle stone age in central Africa. In: Jones, S.C., Stewart, B.A. (Eds.), Africa from MIS 6-2. Springer, Netherlands, pp. 273–299. http://link.springer.com/10.1007/978-94-017-7520-5_15.

Taylor, N., 2022. Riddles wrapped inside an enigma. Lupemban MSA technology as a rainforest adaptation: Revisiting the lanceolate point. Phil. Trans. Biol. Sci. 377 (1849), 20200484. https://doi.org/10.1098/rstb.2020.0484.

Tixier, J., 1984. Economie du débitage laminaire: Technologie et expérimentaiton. IIle Table Ronde Lithique. Meudon-Bellevue, Octobre 1982. Cercle de Recherches et d'Etudes Préhistoriques).

Torres, C., Preysler, J.B., 2020. Experts also fail: a new methodological approach to skills analysis in lithic industries. Journal of Paleolithic Archaeology 3 (4), 889–917. https://doi.org/10.1007/s41982-020-00063-4.

Tribolo, C., Mercier, N., Douville, E., Joron, J.-L., Reys, J.-L., Rufer, D., Cantin, N., Lefrais, Y., Miller, C.E., Porraz, G., Parkington, J., Rigaud, J.-P., Texier, P.-J., 2013. OSL and TL dating of the Middle stone age sequence at diepkloof rock shelter (South Africa): a clarification. J. Archaeol. Sci. 40 (9), 3401–3411. https://doi.org/10.1016/j.jas.2012.12.001.

Van Moorsel, H., 1968. Atlas de préhistoire de la plaine de Kinshasa. Université Lovanium.

Vaquer, J., Colliga, A.M., Cabanilles, J.J., Bordreuil, M., Galant, P., 2014. Les poignards à retouches parallèles couvrantes sur préformes polies en silex de Forcalquier dans la zone nord-occidentale de la Méditerranée 18, 129.

Villa, P., Soressi, M., Henshilwood, C.S., Mourre, V., 2009. The still Bay points of Blombos Cave (South Africa). J. Archaeol. Sci. 36 (2), 441–460. https://doi.org/10.1016/j.jas.2008.09.028.

Weyer, L.D., Pérez, A., Hoguin, R., Forestier, H., Boëda, E., 2022. Temps, mémoire et altérité en technologie lithique: Synthèse et perspectives de l'approche technogénétique française. Journal of Lithic Studies 9 (1). https://doi.org/10.2218/jls.7021, 48-48.

Zhou, Y., Jiang, Y., Liang, G., Li, Y., Forestier, H., Li, H., Chen, P., Wang, L., Liang, T., He, C., 2019. A technological perspective on the lithic industry of the Bailiandong Cave (36-7 ka) in Guangxi: an effort to redefine the cobble-tool industry in South China. C. R. Palevol 18 (8), 1095–1121.