What goes in does not always come out: The impact of the ruminant digestive system of sheep on plant material,and its importance for the interpretation of dung-derived archaeobotanical assemblages

Abstract

On archaeological sites where livestock dung was a major fuel source, plant material that survives digestion intact may well be preserved in the remnants of dung-fuelled fires. Preserved plant remains which were derived from dung relate to the diet of animals, and thus provide a way of investigating the agro-pastoral economies of the past. In order to improve our understanding of the taphonomic processes to which plant material is exposed to during digestion, we applied archaeobotanical methods to the analysis of dung from sheep fed a known diet of cereal and wild plant material. Two clear patterns emerge from these investigations. First, cereal material (grain or chaff) survives digestion poorly and was rarely found in the dung analysed. Second, large proportions of seeds of various wild species survive digestion in an identifiable form, probably due to their small size and/or protective coating. These findings are crucial for reliable interpretation of dung-derived plant material in archaeological settings.     

Towards a distinction between digested and undigested glume bases in the archaeobotanical record from Neolithic northern Greece: A preliminary experimental investigation

Abstract

This study investigates the possibility of distinguishing digested from undigested glume wheat chaff in the archaeobotanical record. To this end the contents of dung pellets collected from a goat fed on einkorn spikelet forks and glume bases are analysed and the derived einkorn chaff examined macroscopically with the aid of scanning electron microscopy. The modern dung pellets contained recognisable glume bases which, compared with undigested ones, demonstrated a ‘rugged’ surface. When these dung pellets were charred, glume bases were still preserved in them. The experimental pellets show that dung can contribute glume bases in archaeobotanical assemblages and that these glume bases may be distinguishable from those derived from glume wheat dehusking by-products used as fuel. These results need to be further explored on archaeobotanical materials. Moreover, further experimentation with different charring regimes, as well as the examination of more experimental specimens is needed.