By 2015, it is estimated that 25% of North American oil will be from sub-Saharan Africa, ahead of the Middle East. Sub-Saharan Africa has been the focus of an intense race for oil by the West, China, India, and other emerging economies, even though it holds only 10% of proven oil reserves, less than the Middle East. This race has been referred to as the second Scramble for Africa. All reasons for this global scramble come from the reserves' economic benefits. Transportation cost is low and no pipelines have to be laid as in Central Asia. Almost all reserves are offshore, so political turmoil within the host country will not directly interfere with operations. Sub-Saharan oil is viscous, with a very low sulfur content. This quickens the refining process and effectively reduces costs. New sources of oil are being located in sub-Saharan Africa more frequently than anywhere else. Of all new sources of oil, are in sub-Saharan Africa. Agriculture Sub-Saharan Africa has more variety of grains than anywhere in the world. Between 13,000 and 11,000 BCE wild grains began to be collected as a source of food in the cataract region of the Nile, south of Egypt. The collecting of wild grains as source of food spread to Syria, parts of Turkey, and Iran by the eleventh millennium BCE. By the tenth and ninth millennia southwest Asians domesticated their wild grains, wheat, and barley after the notion of collecting wild grains spread from the Nile. Numerous crops have been domesticated in the region and spread to other parts of the world. These crops included sorghum, castor beans, coffee, cotton okra, black-eyed peas, watermelon, gourd, and pearl millet. Other domesticated crops included teff, enset, African rice, yams, kola nuts, oil palm, and raffia palm. Domesticated animals include the guinea fowl and the donkey. Agriculture represents 20% to 30% of GDP and 50% of exports. In some cases, 60% to 90% of the labor force are employed in agriculture. Most agricultural activity is subsistence farming. This has made agricultural activity vulnerable to climate change and global warming. Biotechnology has been advocated to create high yield, pest and environmentally resistant crops in the hands of small farmers. The Bill and Melinda Gates foundation is a strong advocate and donor to this cause. Biotechnology and GM crops have met resistance both by natives and environmental groups. Cash crops include cotton, coffee, tea, cocoa, sugar,