Phytolith and Calcitic Spherulite Indicators from Modern Reference Animal Dung from Mediterranean Island Ecosystems: Menorca, Balearic Islands

Abstract

This study illustrates the contribution of plant and faecal microfossil records to interdisciplinary approaches on the identification, composition, taphonomy and seasonality of livestock dung materials. The focus is on the taphonomy of opal phytoliths and calcitic dung spherulites embedded within modern faecal pellets collected from pasture grounds and pens from a range of animals, including cattle, sheep and pigs from three different farms and seasons of the year in Menorca (Balearic Islands, Spain) declared a Biosphere Reserve by UNESCO. Modern reference materials provide comparative plant and dung microfossil indicators on factors affecting the formation, composition, preservation and decay of animal faeces, as well as on the diverse environmental and anthropogenic aspects influencing these. The reported results show relevant changes in phytolith and spherulite composition according to animal species and age, livestock management, seasonality, and grazing and foddering regimes. Both microfossil records provide fundamental information on taphonomic issues that are understudied, such as the variation in the digestibility among different species, including under investigated animals such as pigs, as well on the seasonality of plant and faecal microfossils that are excreted with dung as an important material for reconstructing human-environment interactions which is commonly overlooked in archaeology ; This study was made possible by support from the Consell Insular de Menorca and the Museu de Menorca. M.P. was a Marie Sklodowska-Curie at the University of Reading. The MICROARCHEODUNG project has received funding from the European Union's Horizon 2020 research and innovation programme under the grant agreement No H2020-MSCA-IF-2015-702529. K.D.'s research was supported by an AHRC South West and Wales Doctoral Training Partnership PhD studentship and placement at the University of Reading. She was a visiting research fellow at the Laboratory of Archaeobotany, Department of Prehistory, Autonomous University of Barcelona supervised by M.P. We are very grateful to Raquel Piqué and Karen Hardy (Department of Prehistory), as well as to Joan Manuel Soriano (Department of Geography) for access and further support at the laboratories of the Autonomous University of Barcelona. Special thanks are due to the families of Algendaret Nou, Talatí de Dalt and Es Capell de Ferro that welcomed us into their farms and homes and provided access to the samples and key information for this research. ; Peer reviewed