Introduction

In 2017, the National Museum of Slovenia hosted the Arhaeomusica international exhibition, dedicated to the oldest musical instruments of Europe (de Angeli et al., 2018). During the exhibition, the XV international symposium of the ICTM Study Group on Music Archaeology was carried out in Ljubljana, entitled “Music in the Stone Age”. The main topic of the symposium was the Neanderthal musical instrument discovered in 1995 in the Palaeolithic cave site of Divje babe I (western Slovenia) during systematic excavations carried out by the ZRC SAZU, Institute of Archaeology (Turk, 1997; 2014; Turk et al., 2018).

The symposium saw the presentation of the results of research by Ivan Turk, the researcher of Divje babe I cave and his colleagues, who dedicated many years to the research of this artefact. The results, which were primarily based on experimental work, confirmed the possibility that the find, initially designated as a presumed Mousterian flute, was an intentionally made musical instrument. The practical demonstration consisted of Katinka Dimkaroska’s playing on a reconstruction of the Neanderthal musical instrument and making of the instrument by the experimental archaeologist Giuliano Bastiani. On the audience’s suggestion we decided to present the results from experiments on the investigation of the origin of the perforations at the EXARC conference.

The Neanderthal musical instrument

The Neanderthal-made musical instrument (See Figure 1) kept by the National Museum of Slovenia (inventory number D.b. 652) was made from the left femoral diaphysis of a juvenile cave bear. On the posterior side of the diaphysis, there are two complete perforations and one partially preserved perforation. The fourth perforation, located on the anterior side of the bone, is partly preserved. All four perforations were distributed along the middle of the diaphysis in a straight line. The presumption that the semi-circular notch at the distal end of the posterior side indicating the presence of the fifth perforation was not confirmed (Turk et al., 2005). Both ends of the musical instrument were damaged. The mouthpiece, a bevelled sharp blowing edge, was preserved on the proximal part of the bone (See Figures 1 and 2).

The number of perforations, their shape, and positions on the modified bone was not apparently ascertained as being made by carnivores (cf. Brodar, 1985). The perforations were located on the diaphysis where the compact bone is the thickest and is the hardest to penetrate by carnivores. As the find strongly resembles some of the Upper Palaeolithic bone flutes made of mammal limb bones (Omerzel-Terlep, 1997; Morley, 2013), its finders assumed the modified bone might be a flute (Turk et al., 1995). The possibility of the modified bone being an artefact was supported by the context of the find. Namely, it was found in the Mousterian level in the immediate vicinity of a hearth. Considering the radiocarbon dates of samples from the layer containing the find, its age was at first indirectly estimated as approximately 43,000 years (Nelson, 1997). Later, dating using the ESR method revealed that the layer containing the find was deposited between 50,000-and-60,000-years BP (Blackwell et al., 2007). Considering the archaeological context and age, the find would, if it was confirmed as an artefact (i.e. a musical instrument) represent a discovery of exceptional significance. It would provide strong evidence that Neanderthals were capable of musical expression. All artificially perforated bones, interpreted as Palaeolithic musical instruments (whistles or flutes), originate from the Upper Palaeolithic (Morley 2013). They are the product of an anatomically modern human, to which, beside other cultural innovations, the invention of musical expression is traditionally ascribed (d'Errico et al., 2003).

As Neanderthal burials and rare manifestations of art from Mousterian contexts (Bednarik, 2014; Burdukiewicz, 2014) have been subjected to rigorous scrutiny, so was the modified bone. The resulting critical discussions was unfortunately, distinctly one-sided. Ever since the discovery, the key question revolved around whether the perforations in the bone were of carnivore or artificial origins. The discussion was accompanied by strong denial of all arguments speaking in favour of the anthropogenic origin of holes (Turk et al., 2014; 2020). The edges of perforations on Upper Palaeolithic flutes made from mammal limb bones exhibit clear traces of chiselling or drilling. Irregular serrated rims of the perforations on specimen no. 652 (See Figure 7 c, d) were different than on comparable bone flutes from the Upper Palaeolithic. Since the microscopic analysis did not reveal conventional manufacture marks (i.e. striations and cut marks of stone tools) some scholars took this as evidence that the perforations were made by carnivores. To clarify the origin of the perforations, I. Turk and his colleagues undertook the experimental testing of possible carnivore and artificial creation of the perforations (Turk et al,. 2001). Turk et al.’s (2005; 2006; 2018) study’s results, which included computed tomography, found that the modified juvenile cave bear bone originally had four perforations.

Experimental verification of carnivore hypothesis

To test the hypothesis that carnivores caused the perforations in the bone, metal dental casts of cave bear, hyaena, and wolf dentition were made (See Figure 3). The metal dental casts were used to pierce 29 juvenile and four adult fresh brown bear femora (Turk et al.. 2001).

At Divje babe I, hyena was not represented among the faunal remains, nor was there any other indirect evidence of its presence. It was included in the research as some authors claimed that the perforations were made by a hyaena with its carnassial teeth (Chase and Nowell. 1998; Albrecht et al.. 1998). The results of the experimental piercing tests, do not support the hypothesis that the perforations were made by carnivore dental compression on the bone. Perforations made by the hyaena carnassial teeth were of a more elongated, oval, or rhomboid shape (Turk et al. 2001, Figure 14) (See Figure 4b). D’Errico et al. (1998) recognised only two perforations on the bone (both complete) and that these were made by a cave bear with its canine teeth. This proposal has at least some basis as cave bear was by far the greatest represented carnivore at the site (99.4% of all taxonomically determinable faunal remains). Experimental piercing by the metal dental cast showed that both complete perforations were similar in shape and size to the perforations made by a bear’s canine (See Figure 4a). However, in terms of a bear’s bite, their orientation is problematic. Namely, bear canines have an oval cross section in the labial-lingual direction (Christiansen 2008, Figure 2). Since the two complete perforations were slightly oval in the direction of the longitudinal axis of the femur, during the biting of the bone the bear would straighten the bone in its snout longitudinally to its jaw. It would have to do this for every perforation individually, which is very difficult, if not impossible (cf. Turk et al. 2001, Figure 10). If both complete perforation were made by a transverse bite, they would have to be made separately since the distance between both complete perforations does not correspond to the distance between the canines of an adult cave bear, nor any other of the considered carnivores (Turk et al. 2001).

It is also very difficult for a carnivore, which would gnaw the bone with canine teeth, to set all the perforations into a straight line in several successive bites, since due to the oval shape of bone, the bone slips while compressed by canines, especially if it is fresh and greasy.

During the compression of a bone it was possible to observe how a bear canine tooth acts on the compact bone. During the penetration, the canine tooth pushes the bone tissue on the convex labial side outwards, and pushes the bone obliquely inside on the concave lingual side. Such features on the edge of the perforations were not present on the juvenile cave bear femur. Furthermore, perforations pierced with canine teeth have smooth edges (See Figure 4a), but the edge of the perforations on cave bear femur was irregular and serrated (See Figure 7c, d).

Compression forces necessary to pierce compact bone were measured at the Faculty of Mechanical Engineering of the University of Ljubljana. The force necessary to pierce 3 to 5mm fresh femoral diaphysis of a juvenile brown bear with a blunt canine tooth was between 2.6 and 6.4 kN. Present-day carnivores are not able to produce such compression forces (Christiansen and Wroe. 2007, Table 1). The force required to perforate fresh bone with sharp canine teeth drops to 1.3–3.0 kN (Turk et al.. 2001, Figure 11), which is barely within the limit of the estimated force that the adult male of cave bear can produce (Grandal-d'Anglade, 2010, Table 3). In almost one half of experimental perforations on brown bear femoral diaphyses, the bone shaft split longitudinally. During the compression with sharp canine teeth, the femur usually cracked longitudinally on one or both sides, even before the compact bone was perforated (See Figure 5). If a femur lacked distal and proximal epiphyses, the bone split apart.

The computed tomography analysis (CT) showed that the crack on the posterior side of the juvenile cave bear femur is only superficial (Turk et al., 2005); thereby suggesting this crack did not occur during piercing of the bone. Cracks related to the piercing of a bone went through the entire thickness of the compact bone and were present on both sides of the perforations. Consequently, the V-shaped fractures, which come out of half-preserved Perforations 1 and 4 (See Figure 1), were not contemporary with them. If they had occurred simultaneously with Perforations 1 and 4, there would have been a crack fracture on the preserved side of both perforations.

Experimental verification of the anthropical hypothesis

Pointed stone tools appropriate for piercing bone were found in several Mousterian levels at Divje babe I. In addition to individual fragments of bone points, ad hoc bone tools with a blunt-tips were found in Mousterian levels (Turk M., 2014; Turk and Košir, 2017) (See Figure 6). It should be acknowledged that an experimental archaeologist Giuliano Bastiani and archaeologist François Zoltán Horusitzky, explained how a Neanderthal could have made comparable perforations on animal bones.

G. Bastiani used replicas of pointed Mousterian stone tools from Divje babe I, with which he pierced a recent bear femur in a manner unknown to archaeologists until then (See Figure 10). The new technique used by Bastiani, consisted of chiselling and piercing: a pointed stone tool is used as a chisel and punch at the same time (Bastiani and Turk, 1997; Turk et al., 2001). The edges of these made perforations were irregular and serrated (See Figure 7 a) and morphologically corresponded to the perforations on the modified juvenile cave bear femur (See Figure 7 c, d). Six experimental perforations, produced with this technique, were put under microscopic examination and cut marks were detected on only half of them (d'Errico and Lawson, 2006, p.50). This finding is of great importance since it implies that Neanderthals were able to make perforations on animal bone which lacked conventional manufacture marks. Moreover, the irregular serrated rim of the perforations on the modified juvenile cave bear femur was consistent with the marks left by the manufacture techniques described above.

The technique of perforation manufacturing was upgraded by F. Z. Horusitzky (2003; Turk et al., 2003), who used the replicas of the ad hoc bone tools to perforate bone. By using a pointed stone tool and a bone tool with a blunt tip (See Figure 10), a perforation in the compact bone was made quickly and efficiently. The procedure used was to chisel a dent into the compact bone with a pointed stone tool and then a bone tool with a blunt tip was placed into the dent. This resulted in the bone tool producing a punch of bone after the bone tool was struck with a wooden hammer. The perforations produced by this technique were morphologically identical to the perforations on the modified juvenile cave bear femur and the perforations completely lacked the conventional manufacture marks (See Figure 7 b). Well-pronounced funnel-shaped fractures were observed around the inner edge of the perforations on the experimental bones. These fracture types were observed around the complete Perforation 2 and 3 and partial Perforation 1 and 4 in the modified juvenile cave bear femur (Turk et al., 2005, Figure 6).

Musical verification

From a musical perspective, the modified juvenile cave bone femur was studied by various researchers who confirmed its musical functionality (Kunej, 1997; Kunej and Turk, 2000; Omrzel-Terlep, 1997; Fink, 1997; Atema, 2004; Horusitzky, 2003, 2014). Important findings were reached by the academic musician Ljuben Dimkaroski (2011, 2014), who oriented the instrument differently than the others. Dimkaroski used the proximal part of the diaphysis as a mouthpiece, where a part of the straight cut sharpened edge is preserved and which was not considered by previous researchers (See Figure 1 and 2). With a different orientation of the instrument, the role of Perforation 4, the single perforation on the anterior side, was clarified. In the primary orientation, the location of this perforation was too close to the mouthpiece and thus was dysfunctional. Perforation 4 (See Figure 1) now became useful as a palm hole (to be opened or closed with a palm).

In his musical experiments, Dimkaroski used a replica of the reconstructed musical instrument made on the similar left femur of cave bear cub from Divje babe I (See Figure 8). On the reconstructed instrument, it was possible to perform a series of musical articulations and ornamentations such as legato, staccato, double and triple tonguing, flutter-tonguing, glissando, chromatic scales, trills, broken chords, interval leaps, and melodic successions from the lowest to the highest tones. All these can also be played on the CT replica with reconstructed missing parts (See Figure 1 b). The musical instrument has a range of three and half octaves, and unlike modern wind instruments, it is not tempered (Dimkaroski, 2014). It has three finger holes (Perforations 1–3) on the posterior aspect and a palm hole (Perforation 4) on the anterior aspect of the diaphysis. A mouthpiece with a bevelled sharp blowing edge is located on the anterior proximal part. An opening on the distal part is in the function of bell or closure. With a finger of the right hand, the notch on the posterior distal aspect may be formed into an additional hole. The opening provides the possibility of playing on an open or closed bell, which additionally enriches the tonal range. The sound was created by directed blowing against the sharp edge. The instrument was played two-handed with Perforation 4 being used to extend the air column to twice its length. This was a solution not used by modern wind instruments and implies there is no need for the double length of the instrument and a higher number of holes. According to Dimkaroski (2011, 2014), it is not a flute, but a unique musical instrument whose capability is comparable to modern wind instruments.

Dimkaroski made more than hundred comparable musical instruments, primarily from wood (See Figure 9). He experimented with changing the number, size, and position of the perforations. He came to the conclusion that the number, size, and disposition of the perforations as well as the length of the instrument were deliberately planned with the aim of musical expression. The musical instrument enabled a wide range of sonorities and melodic motions and revealed the artefact as a highly capable wind instrument. Every change in the system, whether changing the length of the instrument, adding or removing holes or the absence of the sharp blowing edge, resulted in poorer musical expression.

Conclusion

Results of the experimental piercings of fresh juvenile bear femurs with metal dental casts from a range of carnivore species indicated that the perforated femur from Divje babe I was not caused by the gnawing/biting actions of carnivores. An animal long bone without epiphyses would split before the carnivore species would be able to perforate it two or more times. Only typical traces of gnawing on both ends of the diaphysis and V-shaped fractures, which were made after the creation of the perforations on the femur, can be interpreted as carnivore damage (Turk et al., 2005; Tuniz et al., 2012).

Archaeological finds from Divje babe I confirm that Neanderthals had appropriate tools for the piercing of bones. Damage such as broken tips and fractures observed on some pointed stone tools (Turk et al. 2018, Figure 13) (See Figures 6, 1c), indicated that they were used to process hard materials. It was proved experimentally that the same type of damage occurs when a wooden hammer hits a tool when chiselling and piercing hard material (Bastiani et al., 2000, p.55, Figure 14; Kunej and Turk, 2000, Figure 15.3; Turk et al., 2001, p.69, Figure 27) (See Figure 10, 3a-c).

Experiments in piercing fresh brown bear bones proved that comparable perforations without conventional manufacturing marks could have been made by Neanderthals with their tools and technology (See Figure 7). The perforations with irregular serrated rims reflected manufacturing using of chiselling and piercing techniques. Thus, such perforations could not be a priori attributed exclusively to carnivore gnawing and biting of bones. With the use of pointed stone tools and a bone punch, the Neanderthals could make a hole into the compact bone in a matter of minutes. While anatomically modern humans drill or simply chisel bones to create perforations—these techniques result in longer times and higher energy consumptions to complete the same task.

No Palaeolithic wind instrument has been discovered complete (Morley, 2013). Musical experiments and testing have been carried out on reconstructed instruments. The advantage of the reconstruction of the modified juvenile cave bear femur bone, i.e., the Neanderthal musical instrument, is that its original length was preserved (11.4 cm). Thus, it was possible to reconstruct credibly the missing parts of the artefact. Furthermore, its manufacture, creation of perforations and the sequence of carnivore damage (most probably by a wolf and not a hyaena) on both ends of the diaphysis was adequately explained by Turk et al. (2018, p. 702).

Acknowledgements

The main author acknowledges the financial support from the Slovenian Research Agency (P6-0283) for the participation at the 11th Experimental Archaeology Conference in Trento, Italy, in May 2019. We thank ZRC SAZU Institute of Archaeology for financing the translation of the paper. We also thank Katinka Dimkaroska and Milojka Magajne from Cerkno Museum for providing us with additional photos.