National Geographic : 2011 Jul
• peasants, have become vital to the sheep industry because of their ability to produce large litters. e Fayoumi chicken, an indigenous Egyptian species dating back to the reign of the pharaohs, is in great demand as a prodigious egg layer with high heat tolerance and resistance to numerous diseases. Similarly, the rare Taihu pig of China is coveted by the world's pig breeders for its ability to thrive on cheap forage foods and its unusual fertility, regularly producing litters of piglets as opposed to an average of for Western breeds. e irony is that the dangerous dwindling of diversity in our food supply is the unanticipated result of an agricultural triumph. e story is well-known. A 30-year-old plant pathologist named Norman Borlaug traveled to Mexico in to help ght a stem rust epidemic that had caused widespread famine. Crossing di erent wheat varieties from all over the world, he ar- rived at a rust-resistant, high-yield hybrid that helped India and Pakistan nearly double their wheat production---and saved a billion people from starvation. is so-called green revolution helped introduce modern industrialized agricul- ture to the developing world. But the green revolution was a mixed bless- ing. Over time farmers came to rely heavily on broadly adapted, high-yield crops to the exclu- sion of varieties adapted to local conditions. Monocropping vast elds with the same geneti- cally uniform seeds helps boost yield and meet immediate hunger needs. Yet high-yield varieties are also genetically weaker crops that require ex- pensive chemical fertilizers and toxic pesticides. The same holds true for high-yield livestock breeds, which o en require expensive feed and medicinal care to survive in foreign climates. e drive to increase production is pushing out local varieties, diluting livestock's genetic diversity in the process. As a result, the world's food supply has become largely dependent on a shrinking list of breeds designed for maximum yield: the Rhode Island Red chicken, the Large White pig, the Holstein cow. In short, in our focus on in- creasing the amount of food we produce today, we have accidentally put ourselves at risk for food shortages in the future. Relying on a small number of food crops is risky, as Irish farmers discovered when the Lumper potato succumbed to blight, resulting in the great Irish potato famine that began in 1845 (memorialized in Dublin above).