Traditional crops and animal breeds are disappearing as intensive agriculture advances, particularly in much of the developing world.

As monocultures spread, the soil loses organic matter and, usually, fertility too. Pests become less diverse, but there are more of them. More pesticides and fertilizers are used to counter the changes. This can accelerate soil degradation, and it can make pests and diseases resistant to the chemicals used to fight them. The way to beat them is to interbreed crops every five to 15 years - often with wild strains.

This worked with stripe rust, a wheat disease that reached epidemic proportions in the United States in the 1960s. Montana was losing a third of its crop to the disease each year, but genes from a wild wheat in Turkey provided resistance to it and 50 other diseases, saving millions of dollars a year.