A new study says Europe's first farmers used far more sophisticated practices than was previously thought. A research team led by the University of Oxford has found that Neolithic farmers manured and watered their crops as early as 6,000 BC.

It had always been assumed that manure wasn't used as a fertiliser until Iron Age and Roman times. However, this 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 findings are published in the early edition of the journal Proceedings of the National Academy of Sciences. The study suggests that Neolithic farmers used the dung from their herds of cattle, sheep, goats and pigs as a slow release fertiliser for crops....