The Smoking Gun in the Charcoal: ethnobotany, taphonomy and absence of evidence in Australian anthracology

The Smoking Gun in the Charcoal: ethnobotany, taphonomy and absence of evidence in Australian anthracology Chae Byrne, Rose Whitau, Fleur King & Emilie Dotte-Sarout Project overview & hypothesis Anthracological (archaeological wood charcoal) analyses have internationally based their palaeoenvironmental interpretations on the 'Principle of Least Effort' (PLE) and its application to wood collecting behaviors; i.e. that all species are collected as fuelwood in direct proportion to their abundance in the environment, according to evolving degrees of selectivity related to occupation phase of a site and biodiversity of its environment. First developed in relation to anthracology by Shackleton and Prins in the 1990's, the PLE has since received some attention by ethnoarchaeologists and anthracologists but has remained somewhat of a side-concern in the discipline. Based on the two dozen or so of published works covering the topic, there are 5 main factors that can influence wood gathering: - function of the fire, - availability of taxa in the landscape, - avoidance of specific taxa and/or landscape units, - conditions of the wood, Data Discussion & Prospects All case studies demonstrate statistically viable assemblages with valid taxonomic diversity measures + taxa frequencies generally coherent with ecology + small bush wood, twigs were present confirming no preservation biases - hence over or underrepresentation of taxa can be assessed. • Emerging picture of regular absence of particular taxa in western regions of semi-arid Australia BHP-UWA Pilbara pilot anthracology project (2013) • Backed up by other sources of information (including archaeological context and taphonomy not discussed here) absence of evidence CAN be argued to be evidence of absence in anthracology • LGM & early Holocene assemblages show absence of ecologically frequent Proteaceae taxa, especially Grevillea (‘beef wood’) from assemblages • Early Holocene also shows absence of Eremophilia (sticky ‘emubush’ or ’turpentine bush’) while it is present in the LGM record UWA (Eureka) Weld-range pilot anthracology project (2012) • Use of local ethnobotanical information provide essential framework for interpretation • Multiproxies archaeobotanical analyses provide valuable information for more precise interpretations • Specific practices of wood/tree resources management can then be discussed and glimpses into past cultural landscape dynamics be offered => Perspectives/focus for future research: • Two Late Holocene assemblages • Multiplication of regional studies and large assemblages • Both show absence of Eremophilia & Grevillea spp. Regional ethnobotanical data for Pilbara/Gascoyne • Ethnobotanical information gathering & ethnoarchaeological projects including experimentation need to be developed as collaborative projects with local communities - conditions of the firewood collection trip. • Regional ethnobotanical data list Grevillea as preferred timber for artefact making and as frequent scarred trees While the archaeological context can provide information to interpret the function of the fire, local sociocultural information and perceptions of the landscape are of paramount importance to interpret the results of anthracological analyses. • TO informants during reference collection making (Weld Range) indicated that Eremophilia was disliked as fuelwood – sticky & spiky wood uneasy to collect References & acknowledgements • Eremophillia presence in the LGM assemblage could then be due to scarcity of wood compelling people to collect unfavoured wood? • We gratefully acknowledge that part of this research was conducted on the land and with the collaboration of Traditional Owners of the Nyiyaparli, Wajarri, Jirrbal & Gooniyandi people. Indeed, to infer the relation between the anthracological diagram and the availability of taxa around a site (for palaeoenvironmental reconstructions), the selection choices have to be recognised and these have to be based on sound local sociocultural frameworks of interpretations as part of the overall study of the site’s taphonomy. We suggest that in Australia where there is rich ethnobotanical information available, one of the most elusive and important form of wood selection might be recognised: avoidance. Is it then possible, in anthracological diagrams, to demonstrate and use evidence of absence as an artefact of its own: giving information about past behaviours and choices, economic or sociocultural practices and ways to experience the landscape? => We consider a range of Australian anthracology case studies showing peculiar absence/low frequency of ecologically abundant taxa in parallel to ethnobotanical data that could support culturally motivated avoidance as the reason for this. Lifeways anthracology project – Riwi cave (2013-2017) • 6 matrix assemblages & 12 combustion features ranging from Pleistocene through to late Holocene/precolonial period • Absence or near-absence (<1%) of ecologically Grevillea/Hakea taxa from all assemblages frequent • Wood artefact fragments preserved in precolonial deposits included distal part of a wooden artefact identified as ‘aerial implement’ • Wood identified as Grevillea/Hakea sp. // regional ethnobotanical data list Grevillea as preferred timber for boomerang manufacture • Byrne C., Dotte-Sarout E., Winton V. 2013. Charcoals as indicators of ancient tree and fuel strategies: An application of anthracology in the Australian Midwest. Australian Archaeology, 77: 94-106. • Cosgrove R, Field J, Ferrier Å . 2007. The archaeology of Australia’s tropical rainforests. Palaeogeogr Palaeoclimatol Palaeoecol 251(1):150-173 • Dotte-Sarout E. & Byrne C. 2013. Archaeobotany (anthracology) of the inland Pilbara: Study of four assemblages from the PAD 10-17 archaeological site. Report for BHP BIO. Archaeology, School of Social Sciences, UWA. • King, F. 2015. Rainforest Aboriginal firewood strategies: investigating palaeovegetation and firewood using charcoal analysis in tropical rainforest of the wet tropics in north east Queensland. Unpublished BA (Hons) thesis, Archaeology, La Trobe University, Melbourne. • Whitau R., Dilkes-Hall I., Dotte-Sarout E., Langley M., Balme J., O'Connor S. 2017. X-ray Computed Microtomography and the Identification of Wood Taxa Selected for Archaeological Artefact Manufacture: Rare Examples from Australian Contexts. Journal of Archaeological Sciences: Reports (6): 536–546. • Whitau, R., Balme, J., O’Connor, S., & Wood, R. 2016.Wood charcoal analysis at Riwi Cave, Gooniyandi country, Western Australia. Quaternary International (Wood Charcoal Science). LaTrobe QLD Tablelands pilot anthracology study (2015) • 1 late Holocene assemblage from toxic nut processing rainforest site • Absence of ecologically frequent Endiandra (‘black walnut’) and Beilschmiedia (‘yellow walnut’) from anthraco samples • Coupled carpological analysis show high frequency of Endiandra and Beilschmiedia charred nutshell fragments • Regional ethnobotanical data list both as significant nut producing trees and record management practices protecting nut producing trees PROTEACEAE TREE FROM THE PILBARA AND WOOD ANATOMY (WHITAU ET AL. 2017)