The Taphonomy of Plant and Livestock Dung Microfossils: An Ethnoarchaeological and Experimental Approach

ABSTRACT

This study examines the contribution of ethnoarchaeological and experimental research to interdisciplinary approaches on the identification and taphonomy of livestock dung. Ethnographic and experimental records provide comparative reference models on a range of taphonomic issues that are still understudied, such as variation in the type and preservation of plant and faecal microfossils that are excreted with dung and the effects of heating. The focus in the present study is on the taphonomy of ingested phytoliths and calcitic spherulites that originate in the digestive tracts of cattle, sheep and goat found in fresh modern dung pellets. The reported records are from the modern farming village of Bestansur, Iraqi Kurdistan. The experimental results show significant changes in microfossil composition and phytolith and spherulite stability and integrity, with increased melting of phytoliths and variations in morphotype composition (e.g. grass short cells appear less stable) from heating at temperatures around 800°C, whereas the spherulite darkening occurs within a range between 500–700°C, with a maximum production at 650°C. This integrated approach illustrates the contribution of the much-needed ethnographic and experimental records of animal dung to understanding of taphonomic issues, which are fundamental for the interpretation of this valuable microfossil material in archaeology.

KEYWORDS:

• Livestock dung
• ethnoarchaeology
• taphonomy
• experimental burning
• phytoliths
• dung spherulites

Acknowledgments

This research was conducted within the framework of the MICROARCHEODUNG and the Central Zagros Archaeological Project (CZAP). The first author’s work has been funded by the European Union’s MICROARCHEODUNG project. The project has received funding from the EU Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No H2020-MSCA-IF-2015-702529. GA’s work has been supported by an University of Reading Undergraduate Research Opportunities Programme fellowship supervised by MP and WM. KD’s research was supported by an AHRC South West and Wales Doctoral Training Partnership PhD studentship and placement.

We are very grateful to all of the CZAP team members for their support and helpful discussions, as well as to the Sulaimaniyah Directorate of Antiquities and Heritage and its Director Kamal Rasheed Raheem for permission to export samples and helpful support. Special thanks are due to the families of Bestansur that welcomed us and other CZAP team members into their homes and provided key information for this research.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by EU: [Grant Number H2020 -MSCA -IF-2015-702529].

Notes on contributors

Marta Portillo

Dr Marta Portillo was a Marie Sklodowska Curie Fellow at the University of Reading. She is an environmental archaeologist specialised in phytoliths and calcitic microfossils in integration with geoarchaeological methods, as well as with experimental and ethnoarchaeological approaches. Her field of expertise investigates human-environment interactions and cultural, economic and technological innovations in the Western Mediterranean and the Near East. She serves at the board of the International Phytolith Society (IPS).

Kate Dudgeon

Kate Dudgeon is a PhD student at the University of Reading with an MSc in Environmental Archaeology. Her research focuses on the investigation of plant-use during the Epipalaeolithic and Neolithic in the Near East, primarily through the analysis of phytoliths and integrated with other environmental archaeological techniques to better understand human-environments.

Georgia Allistone

Georgia Allistone was a UROP Fellow from the Undergraduate Research Opportunities Programme at the Department of Archaeology, University of Reading. She took part in the UROP Placement ‘Human-animal interactions in early sedentary and urban societies in the Near East: phytolith and calcitic microfossil analysis of livestock dung'.

Kamal Raeuf Aziz

Kamal Raeuf Aziz graduated in Archaeology from the University of Erbil, in the Kurdistan Regional Government of Iraq. He is a staff member of the Sulaimani Directorate of Antiquities and Heritage, Sulaimani, Kurdistan Regional Government. He is a key member of many international teams active in this region.

Wendy Matthews

Dr Wendy Matthews is Associate Professor in Archaeology at the University of Reading. She is Co-Director of the Central Zagros Archaeological Project and a specialist in micromorphology, integrated archaeobotany and early agriculture and urbanism. Her interdisciplinary research interests are in the built environment and sustainability from the origins of agriculture to today.