All human societies apart from a handful of remaining hunter/gatherer tribes depend for their very existence on agriculture. Growing crops and domesticating animals has allowed settled societies to become established and culture, arts and science to develop, as people have become freed from the need to spend their time simply subsisting. In the developed world, agriculture forms a tiny part of the economy and is often taken for granted, but it remains vitally important. As well as feeding us, farming has always provided other materials; cotton, flax and wool for example. As we look to reduce our dependency on fossil fuels as industrial feedstocks, we are also beginning to use crops increasingly as sources of renewable raw materials for chemicals, fuels and pharmaceuticals. We also take for granted the effect farming has on our natural landscape and wildlife. The UK was once largely wooded, but was gradually cleared for agriculture. Hedgerows, which we value for the ecological niches they provide for farmland wildlife, are largely a consequence of land enclosure several centuries ago. Skylarks, originally from the steppes of Asia, are now regarded as a native species because arable fields provide a good habitat for them. The very meaning of natural is blurred by our long-term impact on the countryside.