It had always been assumed that manure wasn't used as a fertiliser until Iron Age and Roman times. However, a new research shows that enriched levels of nitrogen-15, a stable isotope abundant in manure, have been found in the charred cereal grains and pulse seeds taken from 13 Neolithic sites around Europe. The study - published in the journal Proceedings of the National Academy of Sciences - suggests that Neolithic farmers used the dung from their herds of cattle, sheep, goats and pigs as a slow release fertiliser for crops.
     Manuring involves a long-term investment in arable land because dung breaks down slowly and crops benefit from its nutrients over many years. This new theory indicates a long-term approach to farming. The authors conclude that early farmers recognised the inherent value of intensively managed land and sought to maintain it for their descendants. This new perspective overturns the traditional view held by scholars that Neolithic farmers were nomadic people who used slash and burn to create temporary farmland for agricultural crops.
     Lead author Dr Amy Bogaard from the School of Archaeology at the University of Oxford said: "The fact that farmers made long-term investments such as manuring in their land sheds new light on the nature of early farming landscapes in Neolithic times. The idea that farmland could be cared for by the same family for generations seems quite an advanced notion, but rich fertile land would have been viewed as extremely valuable for the growing of crops. We believe that as land was viewed as a commodity to be inherited, social differences in early European farming communities started to emerge between the haves and the have-nots."
     The territoriality of early farming groups may help to explain documented events of the period involving extreme violence. The study cites the example of a Neolithic mass burial of the late sixth millennium BCE at Talheim, Germany, which preserves the remains of a community killed by assailants wielding stone axes like those used to clear the land.

Edited from PhysOrg (16 July 2013)