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As of 2004, approximately 800 million hectares of land were in use for food production – approximating an area equivalent to Brazil (1), and allowing for the harvesting of an ample food supply for the majority of a human population approaching 6.3 billion. These land-use estimates include grazing lands (formerly grasslands) for cattle, and represents nearly 85% of all land that can support at least a minimum level of agricultural activity. In addition, farming produces a wide variety of feed grains for many millions of head of cattle and other species of domesticated farm animal (2). In 2003, nearly 33 million head of cattle were produced in the United States, alone (3) In order to support this large a scale of agricultural activity, millions of hectares of hardwood forest (temperate and tropical), grasslands, wetlands, estuaries, and to a lesser extent coral reefs have been either eliminated or severely damaged with significant loss of biodiversity and wide-spread disruption of ecosystem functions.