Use of decayed wood for funerary practices: Archaeobotanical analysis of funerary wooden artefacts from Prehispanic (ca. 400–1500 CE) Gran Canaria (Canary Islands, Spain)

Abstract

The island of Gran Canaria (Canary Islands, Spain) shows great potential for studying the wooden raw materials used by the indigenous population during the Prehispanic period based on xylological analyses from domestic and funerary contexts. This paper includes archaeobotanical data from wooden funerary artefacts recovered from several archaeological contexts of the island and deposited at El Museo Canario (Las Palmas de Gran Canaria, Spain). Our results provide pioneering data as only a few xylological and anthracological analyses have been carried out on this island. Thus, the preferential use of pinewood (Pinus canariensis) for the manufacture of most of the artefacts is suggested, although dragon tree wood (Dracaena sp.) has also been identified in some funerary boards. Wood selection criteria not focusing on healthy wood has been suggested based on a combination of the microscopic observation of fungal decay patterns and archaeoentomological data. In addition to this, morpho-technological analysis suggests extensive woodworking knowledge in a geographic context lacking metal ores. Further xylological and experimental research, including other islands of the archipelago, is needed to obtain a more comprehensive perspective of wood procurement and use during the Prehispanic period.

Introduction

The island of Gran Canaria is located ~200 km off the coast of Morocco, NW Africa, occupying the central area of the volcanic archipelago of the Canary Islands. It is the only Macaronesian archipelago inhabited by an indigenous population before the European expansion during the 14th-15th centuries CE (Fig. 1). Although the exact time of the first human occupation on these islands is still unknown, AMS radiocarbon dating of short-lived materials suggest that the initial colonisation would have taken place at the beginning of the first millennium CE (Hernández-Marrero et al., 2016; Rodríguez-Rodríguez et al., 2017; Velasco-Vázquez et al., 2019). More information is known about the geographical origin of the indigenous population of the Canary Islands, who came from North Africa (Fregel et al., 2019) and remained practically isolated until the Europeans arrived on the archipelago in the 14th century CE. The definitive conquest by the Crown of Castile was completed at the end of the 15th century CE.

Regarding our knowledge about the indigenous society of the Canary Islands, archaeological material and historical written sources are the two main sources of information. Both sources reveal the existence of a complex society on Gran Canaria, with marked personal differences and a strong hierarchisation of the social order (Velasco-Vázquez and Martín-Rodríguez, 1997-1998; Santana-Cabrera et al., 2011-2012). Social inequality regarding funerary practices is also mentioned in the narrative written sources (Abreu-Galindo, [1632] 1977; Torriani, [1592] 1978) and has been evidenced by the specific placement of certain individuals within funerary spaces, the effort invested in certain mortuary monuments, and the treatment of corpses (Velasco-Vázquez and Martín-Rodríguez, 1997-1998; Alberto-Barroso and Velasco-Vázquez, 2008; Alberto-Barroso et al., 2016; Delgado-Darias et al., 2017). From a diachronic point of view, the earliest dates from funerary contexts (5th-6th century CE) correspond to some exceptionally well-preserved naturally mummified human remains recovered from funerary caves in mountainous areas of the island (mostly in Acusa and Guayadeque) (Delgado-Darias, 2017; Alberto-Barroso et al., 2019). Between the 8th and 11th centuries CE, the sepulchral use of volcanic lava surfaces through tumuli construction can be noted in different areas of the island (Jiménez-Gómez and del Arco-Aguilar, 1977; del Arco-Aguilar, 1983; Alberto-Barroso et al., 2014), probably indicating socioeconomic changes supported by indicators of social tension during this chronological period, such as evidence of physical violence (Delgado-Darias et al., 2020). Finally, from the 11th century CE onwards a new type of burial appeared, consisting of cists and graves in a necropolis, although the use of funerary caves lasted for some time (Alberto-Barroso et al., 2016; Delgado-Darias, 2019). During this period, the abundant radiocarbon dates from communal granaries suggest the production of an agricultural surplus, the existence of a demographic increase, and economic intensification (Morales et al., 2009, 2014; 2018; Rodríguez-Rodríguez et al., 2017; Henrí quez-Valido et al., 2020).

Despite the traditional duality established between mummified and non-mummified humans, recent research points to a standardised funerary practice of wrapping the corpse before burial, which is documented on Gran Canaria from the 5th to the 15th century CE (Alberto-Barroso and Velasco-Vázquez, 2008; Alberto-Barroso et al., 2016; Delgado-Darias et al., 2017). Thus, the body would have been tightly wrapped in a shroud of animal skins and/or plant fibers that would have been tied to the body at several points (arms, elbows, legs, and ankles). Considering this, differences between individuals based on the quality and quantity of the material used for the shrouds can be detected (Delgado-Darias et al., 2017), but corpse handling was a widespread funerary practice throughout the entire population. Indeed, the contrast observed between mummified and non-mummified corpses could be explained by differential preservation according to the funerary deposit. Thus, organic tissues of human, animal, and plant origin are potentially better preserved in funerary caves than in other contexts such as cists or graves with no tumular cover (Alberto-Barroso et al., 2016).

Narrative written sources, as well as some administrative and legislative documents, provide useful information regarding wood use by the indigenous population living at the moment of contact with European explorers. However, these documents do not include detailed data about selection criteria, woodworking processes, or the exact role of woody resources within funerary practices. In this regard, it should be noted that the absence of metal ores in the archipelago led to a process of adaptation of wood exploitation strategies among the indigenous Berber populations using volcanic stone tools. Thus, Canarian lithic industries reveal different scenarios of technological strategies on each island based on raw material availability, social needs and technological innovations (Rodríguez-Rodríguez, 1998). Tool-mark and use-wear analyses applied on wooden artefacts are still very scarce (Vidal-Matutano et al., 2020b), although there is evidence of woodworking tools which served for chopping, sawing and scraping wood (Rodríguez-Rodríguez, 1993, 1998; Naranjo-Mayor and Rodríguez-Rodríguez, 2015).

The use of funerary boards on Gran Canaria and other islands in the archipelago is mentioned by Abreu-Galindo ([1632] 1977). The specific use of tea-wood, i.e. the resinous incorruptible heartwood characteristic of the Canary Island pine (Pinus canariensis) after 30 years of growth (Climent et al., 1998, 2006), has been described extensively. No other references to wood use in funerary contexts are specified in any depth, with the exception of wooden coffins, which are always described as a funerary practice among the highest social group (Abreu-Galindo, [1632] 1977; Marín de Cubas, [1694] 1986). However, the archaeological record has only provided exceptional evidence of a wooden coffin dated to the 8th-10th century CE, which is included in this work (Delgado-Darias, 2019).

Archaeological research regarding Prehispanic funerary contexts from the archipelago has yielded abundant evidence of desiccated wood remains directly associated with burials. Indeed, branches and wooden boards made from Juniperus turbinata ssp. canariensis (savin), Pinus canariensis, and Juniperus cedrus (Canary Island juniper) have been recovered at several archaeological sites of the nearby island of Tenerife (Álvarez-Delgado, 1947; Lorenzo-Perera, 1976; Arnay de la Rosa et al., 2011). In addition, the anthracological analysis of a combustion structure from the funerary cave Arenas-1 (Tenerife) was interpreted by Machado et al. (2002) as the preferential use of the Canary Island pine, savin, and olive (Olea europaea ssp. cerasiformis) wood, which may have had some symbolic value among the indigenous groups of Tenerife. For Gran Canaria, very few xylological analyses of wooden artefacts from funerary contexts have been carried out to date, although other plant remains have been identified, such as the use of pine needles to cover the surface of the burial site (Martín-Rodríguez et al., 1999, 2003). In this sense, wood procurement seems to be related to the specific purpose (wood for fuel, timber or structural elements, funerary practices or for the fittings of the granaries, Table 1). Although anthracological data from Gran Canaria is still very scarce, ongoing charcoal analyses from several sites of the island (Cueva Pintada and Playa Chica, in the municipality of Gáldar) as well as published anthracological data (Machado, 2009) point out to the use of, at least, 27 different taxa. Charcoal remains from domestic combustion structures show a broad use of taxa gathered in different plant formations (pine forest, laurel forest, thermophile forest and coastal vegetation). Nevertheless, xylological analyses of desiccated wood reveal different wood acquisition criteria. On the one hand, wood procurement for the fittings of the silos focused on pine and fig tree (Ficus carica), with lower proportions of other thermophylous and mesophylous species (Vidal-Matutano et al., 2020b). On the other hand, ongoing analyses of structural elements (doors, doorjambs, beams) and domestic wooden artefacts (containers, trays, tools) point out to the collection of a few species of the pine forest (pine), the laurel forest (Lauraceae, Morella faya and Visnea macaronera, species endemic to Macaronesia) and the thermophile forest (Phoenix canariensis -Canary Island palm-, Salix canariensis -Canary Island willow-, fig tree and Dracaena sp. -dragon tree-). Finally, funerary contexts analysed to date indicate a reduced use of taxa.

In this paper, we present xylological data from several Prehispanic wooden funerary artefacts preserved by desiccation and deposited at El Museo Canario (Gran Canaria, Canary Islands) (Fig. 1). Thus, the main purposes of this study have been to: 1) identify the woody raw material used by the indigenous population in several funerary contexts dating to different chronological periods, 2) discuss possible selection criteria and wood reuse processes, and 3) shed light on the degree of preservation of these organic materials based on the analysis of macroscopic and microanatomical features affecting the ligneous cellular structure.