A peer-reviewed version of this preprint was published in PeerJ on 17 January 2017. View the peer-reviewed version (peerj.com/articles/2903), which is the preferred citable publication unless you specifically need to cite this preprint. Kubicka AM, Rosin ZM, Tryjanowski P, Nelson E. 2017. A systematic review of animal predation creating pierced shells: implications for the archaeological record of the Old World. PeerJ 5:e2903 https://doi.org/10.7717/peerj.2903 A systematic review of natural processes in creating pierced shells: implications for the archaeological record Anna Maria Kubicka, Zuzanna M Rosin, Piotr Tryjanowski, Emma Nelson Background. The shells of molluscs survive well in most sedimentary contexts and yield information about the diet of prehistoric humans. They also yield evidence of symbolic behaviours, through their use as beads for body adornments. Researchers often analyse the location of perforations in shells to make judgements about their use as symbolic objects (i.e., beads), the assumption being, that holes attributable to deliberate human behaviour are more likely to exhibit low variability in their anatomical locations, while holes attributable to natural processes yield more random perforations. However, there are non-anthropogenic factors that can cause perforations in shells and these may not be random. The aim of the study is to look at the association between variation of holes in shell beads from archaeological sites and shells pierced by natural (non-human) processes. Methods. Two hundred and sixty scientific papers retrieved from online databases by using keywords, (e.g., ‘shell beads’; ‘pierced shells’); 77 of these publications enabled us to conduct a systematic review and assess the location of the hole in the shell beads in the published articles. Results. Almost all archaeological sites described shells beads with holes in a variety of anatomical locations. High variation of hole-placement was also found within the same species from the same site, as well as among sites. In contrast, predators were more specific in where they attacked molluscs; birds often select the thinnest part of the shell, while molluscs and cephalopods target thicker parts. Discussion. These results indicate that variation in hole-location on shells pierced by humans is greater than variation in the placement of holes created by natural processes. Consequently, these patterns are opposite to those expected. We also found that Gastropod and Bivalve predators choose similar hole locations to humans. Research into human shell-beads recovered from archaeological contexts should take into account non-anthropogenic factors, which can lead to more realistic scenarios of the cultural behaviours of prehistoric people. PeerJ PrePrints | https://doi.org/10.7287/peerj.preprints.1710v1 | CC-BY 4.0 Open Access | rec: 4 Feb 2016, publ: 4 Feb 2016 1 A systematic review of natural processes in creating pierced shells: implications for 2 the archaeological record 3 Anna Maria Kubicka1, Zuzanna M. Rosin2, Piotr Tryjanowski3, Emma Nelson4,5 4 5 1Adam Mickiewicz University in Faculty of Biology, Department of Human 6 Evolutionary Biology, Poland.Poznań, 7 2Adam Mickiewicz UniversityPoznań, in Institute of Experimental Biology, Department of 8 Cell Biology, Poland. Poznań, 9 3 UniversityPoznań, of Life Sciences, Institute of Zoology, Poland. 10 4SchoolPoznań of Medicine, University of Liverpool, Liverpool, UKPoznań, 11 5Archeology, Classics and Egyptology, University of Liverpool, Liverpool, UK. 12 13 Corresponding author: 14 Anna Maria Kubicka 15 Umultowska 89, PL61-614, Poland 16 e-mail address: [email protected]ń, 17 ABSTRACT 18 Background. The shells of molluscs survive well in most sedimentary contexts and yield 19 information about the diet of prehistoric humans. They also yield evidence of symbolic 20 behaviours, through their use as beads for body adornments. Researchers often analyse the 21 location of perforations in shells to make judgements about their use as symbolic objects 22 (i.e., beads), the assumption being, that holes attributable to deliberate human behaviour 23 are more likely to exhibit low variability in their anatomical locations, while holes 24 attributable to natural processes yield more random perforations. However, there are non- 25 anthropogenic factors that can cause perforations in shells and these may not be random. 26 The aim of the study is to look at the association between variation of holes in shell beads 27 from archaeological sites and shells pierced by natural (non-human) processes. 28 Methods. Two hundred and sixty scientific papers retrieved from online databases by 29 using keywords, (e.g., ‘shell beads’; ‘pierced shells’); 77 of these publications enabled us to 30 conduct a systematic review and assess the location of the hole in the shell beads in the 31 published articles. 32 Results. Almost all archaeological sites described shells beads with holes in a variety of 33 anatomical locations. High variation of hole-placement was also found within the same 34 species from the same site, as well as among sites. In contrast, predators were more 35 specific in where they attacked molluscs; birds often select the thinnest part of the shell, 36 while molluscs and cephalopods target thicker parts. 37 Discussion. These results indicate that variation in hole-location on shells pierced by 38 humans is greater than variation in the placement of holes created by natural processes. 39 Consequently, these patterns are opposite to those expected. We also found that Gastropod 40 and Bivalve predators choose similar hole locations to humans. Research into human shell- 41 beads recovered from archaeological contexts should take into account non-anthropogenic 42 factors, which can lead to more realistic scenarios of the cultural behaviours of prehistoric 43 people. 44 Keywords: Gastropoda, Scaphopoda, Bivalvia, shell beads, interspecies interactions, 45 jewellery, predators. 46 INTRODUCTION 47 The adornments of prehistoric people play an important role in our understanding 48 of the evolution of human behaviour (Bednarik, 2001; Gutiérrez-Zugasti et al., 2013) 49 because they can indicate evolutionary changes in the cognitive and linguistic abilities of 50 early humans (Vanhaeren & d’Errico, 2006; Schick & Toth, 2013; Stiner, 2014). These 51 findings help anthropologists to construct a picture of the life of prehistoric human groups, 52 and can give insights into their social status (Bednarik, 1998; Stiner, 1999; Vanhaeren & 53 d’Errico, 2005), group membership, age or marital status (Kuhn et al., 2001). Personal 54 adornments made from molluscs survive well in most sedimentary contexts (Bar-Yosef- 55 Mayer & Beyin, 2009) and can be interpreted in a various ways, depending on the context 56 of the find. Usually the deposits are associated with graves (Vanhaeren et al., 2004; 57 Vanhaeren & d’Errico, 2005), human made-shelters (Kuhn et al., 2001) and hearths (Douka 58 et al., 2014). Some of the earliest forms of body adornments are in the form of shells beads 59 and date back to ~75 Kya (Henshilwood et al., 2004)and ~82 Kya (Bouzouggar et al., 60 2007), possibly even 100-130 Kya (Vanhaereny et al., 2006)or earlier (Bednarik, 2015). 61 However, others researchers argue that this “modern behaviour” was probably established 62 much earlier and taphonomic processes mean that shell beads are simply the earliest 63 material associated with body adornment that have survived (Bowdler & Mellars, 1990; 64 Noble & Davidson, 1996; Botha, 2008, 2010). 65 Generally shell artefacts are limited to marine molluscs found in habitation levels 66 (Vanhaeren & d’Errico, 2006), while evidence of land and freshwater gastropods are more 67 rare [e.g., El Cuco, 23-34 Kya(Gutiérrez-Zugasti et al., 2013)]. The majority of shell artefacts 68 are known from the Palaeolithic and Neolithic sites in Levant, South Africa, Europe, North 69 America and Asia. Interestingly, while early dated shell remains from occupation layers in 70 Africa are only associated with anatomically modern humans (AMHs), molluscs recovered 71 from Middle Palaeolithic (MP) layers in Europe are mainly related to Neanderthal 72 occupations(Gutiérrez-Zugasti et al., 2013). Although some researchers have argued that 73 strategies for exploiting coastal resources do not differ between European Neanderthals 74 and AMHs in Africa during the MP and MSA (Stringer & Barton, 2008), others interpret the 75 evidence differently, with Neanderthals exploiting marine environments infrequently 76 compared to AMH (Shipman, 2015). 77 Researchers make detailed analyses of adornments, radiometric dates and 78 stratigraphic information to explain innovations in shell beads, as well as the spread of 79 cultural traditions (Kuhn et al., 2001). Piercings in shells carry indications as to the 80 placement, the rigidity or flexibility of the ornament within a larger assemblage and, in 81 relation to the substrate or cord, the direction the traction was exerted (Cristiani, 2012). 82 Based upon this kind of painstaking evidence-gathering, experts make judgements as to 83 whether perforations in shells from archaeological sites are anthropogenic in origin or 84 formed by natural processes (d’Errico et al., 2005), such as those made by hole-drilling 85 animals (predators, parasites; (Kowalewski, 2004; Li, Young & Zhan, 2011)). While the 86 location of the perforation is only part of raft of evidence that indicates an operational 87 chain (starting with the collection of the raw material,