INTRODUCTION
For a long time, the ultimate function of a number of artifacts made of bone with a set of asymmetric rows of triangular indentations was an enigma that generated various explanations in the archaeological literature (Semenov Reference Semenov1964; Briois et al. Reference Briois, Poplin and Rodet-Belarbi1995; Benco et al. Reference Benco, Ettahiri and Loyet2002; Rodet-Belarbi et al. Reference Rodet-Belarbi, Forest, Gardel and Guinouvez2002). In the early 21st century, some ethnographic studies demonstrated that blacksmiths used these worked bones as an anvil to anchor the metal blade of a sickle while it was being cut to make a serrated edge (Aguirre et al. Reference Aguirre, Etxeberria and Herrasti2004; Esteban and Carbonell Reference Esteban and Carbonell2004). The characteristic triangular marks on these objects were the result from the hammering of the chisel on the bone surface. This technique of making toothed-blade sickles has been attested to be in use until the second half of the 20th century in Spain and Portugal (Moreno-García et al. Reference Moreno-García, Pimenta, López and Pajuelo2007), and until today in Tunisia (Rodet-Belarbi et al. Reference Rodet-Belarbi, Esteban, Forest, Moreno-García and Pimenta2007; Anderson et al. Reference Anderson, Rodet-Belarbi and Moreno-García2014).
In recent years, the research has begun to focus on the establishment of the origin, chronological framework, and dispersal patterns of these implements. According to the last data summarized (Moreno-García et al. Reference Moreno-García, Esteban, Pimenta, López and Morales2006; Rodet-Belarbi et al. Reference Rodet-Belarbi, Esteban, Forest, Moreno-García and Pimenta2007; Grau Reference Grau2012; Anderson et al. Reference Anderson, Rodet-Belarbi and Moreno-García2014), the spatial distribution of the bone anvils is very wide, but mainly focused around the Mediterranean and Black Sea. The origin of these objects is still debated, but the data show that the earliest bone anvils were documented in the Hellenistic–Roman period in southeastern Europe (about 5th century BC to 2nd century AD; Beldiman et al. Reference Beldiman, Sztancs, Rusu-Bolineţ and Achim2011, Reference Beldiman, Rusu-Bolindeţ, Sztancs and Bădescu2014), and in the Roman period for the central Mediterranean (2nd century BC to 1st century AD; Gál and Bartosiewicz Reference Gál and Bartosiewicz2012). In the western Mediterranean, at least 500 bone anvils from the Iberian Peninsula, north Africa, Sardinia, and France have been documented, thereby becoming the most explored region (Figure 1). However, the earliest artifacts in this zone have been dated to the 5th–7th centuries AD by pottery association (Moreno-García et al. Reference Moreno-García, Esteban, Pimenta, López and Morales2006; Grau Reference Grau2012; Anderson et al. Reference Anderson, Rodet-Belarbi and Moreno-García2014). This chronological gap of nearly 400–500 yr between the western and eastern part of the Mediterranean distribution implies that the bone anvil originated in the eastern Mediterranean (Beldiman et al. Reference Beldiman, Sztancs, Rusu-Bolineţ and Achim2011, Reference Beldiman, Rusu-Bolindeţ, Sztancs and Bădescu2014). Other authors consider this geographic difference a bias of the archaeological record (Moreno-García et al. Reference Moreno-García, Esteban, Pimenta, López and Morales2006; Gál and Bartosiewicz Reference Gál and Bartosiewicz2012; Grau Reference Grau2012; Anderson et al. Reference Anderson, Rodet-Belarbi and Moreno-García2014).
Distribution of sites with known bone anvils from the western Mediterranean (after Moreno-García et al. Reference Moreno-García, Esteban, Pimenta, López and Morales2006; Rodet-Belarbi et al. Reference Rodet-Belarbi, Esteban, Forest, Moreno-García and Pimenta2007; Grau Reference Grau2012; Anderson et al. Reference Anderson, Rodet-Belarbi and Moreno-García2014).
In this paper, we report on a bone anvil recovered in the archaeological site of Montefí (Ciutadella), in the island of Menorca (Figure 1 and 2). This artifact was tentatively dated by pottery association between the 1st and 3rd century AD (Herránz and León Reference Herranz and León2007), challenging the temporal scope of the bone anvils in the western part of the Mediterranean. Through the direct accelerator mass spectrometry (AMS) 14C dating, we present sound evidence for the chronological placement of the artifact, and offer new insights on the historical framework and implications that the spread of these craftsman tools entailed.
The bone anvil from Montefí, Menorca (MTF05-319-161)
MATERIAL AND METHODS
During roadworks construction, a fragment of a bone anvil was identified in a new archaeological area at the southern edge of the prehistoric settlement of Montefí (Herránz and León Reference Herranz and León2007). This site, located in the southwest of the island of Menorca (western Mediterranean), features a number of well-preserved megalithic structures of the Iron Age although other chronological phases have also been documented (Herránz and León Reference Herranz and León2007). The artifact was recovered in the sediment (SU-319) filling a storage pit excavated on the natural limestone (Pit-17). This structure, globe-shaped with a cylindrical entrance and 2.3 m deep, contained several pottery shards, animal bones, and a human body. The pottery from within the infill has been provisionally dated between the 1st to 3rd centuries AD (Herranz and León Reference Herranz and León2007).
The bone anvil (MTF05-319-161) only retains a fragment of ~7.5 cm in length and was made on a cattle (Bos taurus) metapodial (Figure 2). This is in line with the archaeological record as most bone anvils correspond to fragments of diaphysis, proximal or distal halves of long bones of cattle, although other species and skeletal elements have also been observed (Rodet-Belarbi et al. Reference Rodet-Belarbi, Forest, Gardel and Guinouvez2002; Moreno-García et al. Reference Moreno-García, Pimenta, López and Pajuelo2007; Beldiman et al. Reference Beldiman, Sztancs, Rusu-Bolineţ and Achim2011). The small preserved section of the artifact limits our ability to identify in more detail the skeletal element or anatomical side. Both preserved sides of the metapodial show signs of having been smoothed down during the manufacture of the bone anvil, but just one presents the characteristic marks of its use (i.e. set of triangular marks disposed transversely to the axis).
A sample 38.6 mm long was selected from the broken end of the lateral side of the bone anvil and sent for AMS analysis to the KIK-IRPA Radiocarbon Laboratory facility in Brussels, Belgium. The pretreatment of the sample was conducted following the Longin (Reference Longin1971) method, but using a preparation line adapted for (small) AMS samples. A supplementary NaOH step (1%) to remove humic acids was added. The hydrolyzed sample was then freeze-dried. A 20.6-mg sample of the hydrolyzed protein was combusted and the CO2 processed into graphite using a Fe/H2 reaction (Van Strydonck and Van der Borg 1990–Reference Van Strydonck and Van der Borg1991) and dated by AMS using a MICADAS (Boudin et al. Reference Boudin, Van den Brande, Synal, Wacker and Van Strydonck2015). A subsample of the hydrolyzed bone was used for C:N ratio and stable isotope measurements using a Thermo Scientific™ Flash EA/HT elemental analyzer, coupled with a Thermo Scientific™ Delta V™ Advantage isotope ratio mass spectrometer (IRMS) via a Conflo IV interface.
RESULTS
The AMS analysis of the bone anvil produced an age of 1905±32 BP (RICH-22211). The carbon to nitrogen atomic weight ratio (C:N=3.2) indicates that the bone protein was within recognized ranges for good preservation (C:N range of 2.9 and 3.6; DeNiro Reference DeNiro1985). The other monitored parameters, including percentage collagen yield (2.9%), percentage of carbon (34.8%C), and percentage of nitrogen (12.5%N), also showed that the sample integrity and preservation were good. The calibration of this date was performed using OxCal v 4.2 (Bronk Ramsey Reference Bronk Ramsey2009) with IntCal13 data (Reimer et al. Reference Reimer, Bard, Bayliss, Beck, Blackwell, Bronk Ramsey, Buck, Edwards, Friedrich, Grootes, Guilderson, Haflidason, Hajdas, Hatté, Heaton, Hoffman, Hogg, Hughen, Kaiser, Kromer, Manning, Niu, Reimer, Richards, Scott, Southon, Staff, Turney and van der Plicht2013). The calibrated date, at two standard deviations (95.4% probability), has a range between cal AD 24 to 213. Taking into consideration a less restrictive but still very robust interval (91.5% probability), the dated bone anvil is situated between cal AD 24 to 178. Both age ranges are coherent with the previous pottery date of the archaeological context (i.e. 1st to 3rd century AD). It is therefore reasonable to postulate that the bone anvils were introduced in Menorca, at least, during the Roman period.
DISCUSSION
The bone anvil of Montefí is the first documented and published date of the Balearic Islands. This new evidence supports earlier claims that the temporal and spatial record of the bone anvils was not reflecting a real picture but a biased archaeological record (Moreno-García et al. Reference Moreno-García, Esteban, Pimenta, López and Morales2006; Gál and Bartosiewicz Reference Gál and Bartosiewicz2012; Grau Reference Grau2012; Anderson et al. Reference Anderson, Rodet-Belarbi and Moreno-García2014). Our survey has also documented two other unpublished bone anvils from Mallorca, but both come from Medieval and post-Medieval contexts (Can Oleo in Palma and Carrer de l’Estrella in Manacor). This evidence allows us to incorporate the Balearic Islands to the known geographic range where bone anvils were present.
However, it is in the temporal framework that the dated bone anvil from Montefí has its most significant implications. Recent age estimates based on associated pottery suggest that the earliest bone anvils may have first appeared in the western Mediterranean at roughly the 5th–7th century AD (Moreno-García et al. Reference Moreno-García, Esteban, Pimenta, López and Morales2006; Grau Reference Grau2012). This is around 300–400 yr later than the dated anvil of Montefí. Thus, the dated artifact we present not only represents the first archaeological anvil of the Balearic Islands but also constitutes the earliest evidence of the western Mediterranean.
Origin and Distribution of Bone Anvils
Traditionally, it has been pointed out that the earliest bone anvils come from Olbia in south-central Ukraine and are dated to the Hellenistic period (Moreno-García et al. Reference Moreno-García, Pimenta, López and Pajuelo2007; Beldiman et al. Reference Beldiman, Sztancs, Rusu-Bolineţ and Achim2011). Similar finds have been reported from the contemporaneous sites of Phanagoreia and Neapolis, also on the Black Sea coast (Semenov Reference Semenov1964). This has led to suggest the Black Sea Basin as place of origin of the bone anvil and from where it was dispersed to the Mediterranean (Beldiman et al. Reference Beldiman, Sztancs, Rusu-Bolineţ and Achim2011, Reference Beldiman, Rusu-Bolindeţ, Sztancs and Bădescu2014). Unfortunately, the contextual information and by extension the chronology of all these bone tools remains poorly known (e.g. Grau Reference Grau2012). However, within the same area, other bone anvils with a more archaeologically grounded context have been dated to the 1st–2nd centuries AD (Roman site of Histria; see Beldiman et al. Reference Beldiman, Sztancs, Rusu-Bolineţ and Achim2011, Reference Beldiman, Rusu-Bolindeţ, Sztancs and Bădescu2014).
In the absence of more reliable data from the eastern regions, the earliest attested bone anvil comes from the central Mediterranean. It is a directly AMS 14C-dated bone anvil found in a kiln deposit from Pantanello in southern Italy (Gál and Bartosiewicz Reference Gál and Bartosiewicz2012). The calibrated age at 2σ (i.e. 95.4% certainty) ranges from 190 BC to AD 10 (SUERC-30885; 2070±35 BP).
Taking into account the new archaeological record for the western Mediterranean, the updated temporal framework for bone anvils suggests that they were probably produced for the first time during the early Roman period. Thus, bone anvils originated in the Italic Peninsula, and then spread across the Mediterranean as the Roman expansion was taking place. The spatial distribution of the earliest artifacts reflects a general coastal pattern, suggesting that the diffusion process may have been mediated through shipping routes. After this first phase, the scope of the bone anvils was extended into the continent where they became widespread, especially in Medieval times, when, as already pointed out, most archaeological specimens have been recorded (Moreno-García et al. Reference Moreno-García, Esteban, Pimenta, López and Morales2006, Reference Moreno-García, Pimenta, López and Pajuelo2007; Grau Reference Grau2012; Anderson et al. Reference Anderson, Rodet-Belarbi and Moreno-García2014).
Tracking Metal Sickles with a Serrated Edge and Its Socioeconomic Implications
The interpretative value of these tools goes beyond determining the spatial and temporal scope of its distribution. The presence of a bone anvil is inherently linked to the use of toothed metal sickles and consequently to the agricultural practices that they imply (Anderson et al. Reference Anderson, Rodet-Belarbi and Moreno-García2014).
Agriculture was one of the key drivers of the Roman economy. Among the most important crops traded in this period (i.e. grains, olives, and grapevines), grain played a major role as staple food (e.g. Duncan-Jones Reference Duncan-Jones1982; Green Reference Green1986; Bowman and Wilson Reference Bowman and Wilson2013). The sickle was a tool specifically associated in harvesting this cereal and although its manufacture was not a Roman innovation, it has been shown that some technical improvements took place at that time (White Reference White1967, Reference White1970; Mongez Reference Mongez1983). One of the conditioning factors of this change was the increased availability of the hitherto scarce iron metal (Margaritis and Jones Reference Margaritis and Jones2009) and thus the potential to expand the repertoire of implements and the scale of production (White Reference White1967).
Some ancient authors, such as Columella, Varro, and Palladius, mention different types of implements with curved blades (falx) that probably were designed to make full use of the exceptional fragmentation and variation of the Mediterranean landscapes and crops (e.g. Horden and Purcell Reference Horden and Purcell2000). Nevertheless, the ordinary sickle (falx messoria), either with a plain or serrated edge, was considered one of the most extended tools to harvest grain (White Reference White1967).
Metal sickles with toothed cutting edges, as opposed to sickles with smooth blade, are regularly considered to be more efficient in crop harvesting (Sutjana Reference Sutjana2000). This is particularity true for the Mediterranean climatic zone where cereal stalks tend to be tougher due to its high silica content (White Reference White1967; Anderson et al. Reference Anderson, Rodet-Belarbi and Moreno-García2014). Compared with the smooth-edged sickle, the serrated sickle required little if any sharpening in the field, whereas smooth blades had to be resharpened as harvesting proceeded (McClelland Reference McClelland1997). This results in a reduction of working time loss maintaining the tool and hence to a higher harvesting capacity. Thus, tracking the development and use of these serrated sickles could provide new insights of past agricultural intensification processes.
One major constraint is the small number of such tools in the archaeological record. This is probably due to the fact that iron tools are usually recovered fragmented and their state of preservation does not always allow the identification of specific features (Olsen Reference Olsen1988). For this reason, although Roman iron sickles have been reported (e.g. Sanahuja Reference Sanahuja1971; Mezquíriz 2007–Reference Mezquíriz2008), it is not always easy to identify the specific presence of toothed blades (Anderson et al. Reference Anderson, Rodet-Belarbi and Moreno-García2014). In this regard, it becomes evident that tracking the better-preserved bone anvils would have an important role to play, at least in those areas where they were used in the manufacture of metal sickles with a toothed edge (Poplin Reference Poplin2009).
CONCLUSIONS
Understanding regional processes requires a solid grasp of the temporal relationship between objects and events. Following previous works (e.g. Rick Reference Rick2001; Gál and Bartosiewicz Reference Gál and Bartosiewicz2012), this paper highlighted the use of directly AMS-dated artifacts to develop chronologies and trace the dissemination of technological change.
The 14C dating presented here significantly refines the chronology of the presence of bone anvils in the western Mediterranean, suggesting that these artifacts appeared around the Roman period. At the same time, these new data also open the possibility that the dispersion of this craftsman’s tool could have occurred in a relatively short period of time following the Roman expansion.
ACKNOWLEDGMENTS
This research is included in the Research Project “Cambios holocénicos en la biodiversidad animal de las islas de la Macaronesia y de Baleares” (CGL2012- 38087; PI Dr J. A. Alcover) of the Spanish Ministerio de Ciencia e Innovación. This is also part of the research activities of the Equip de Recerca Arqueològica i Arqueomètrica de la Universitat de Barcelona (ERAAUB), Consolidated Group (2014 SGR 845). We thank the Consell de Menorca, which gave us permission for sampling the bone anvil. We would also like to thank to Mathieu Boudin for his assistance in the 14C analyses. The manuscript has benefited by the comments of Nancy Beavan and two anonymous reviewers.
