National Geographic Magazine - July 2011
Food Ark - By Charles Siebert
Experts estimate we have lost more than half of the world's food varieties over the past century. In the Philippines, thousands of varieties of rice once thrived; now only about a hundred are grown there. In China, 90 percent of the wheat varieties cultivated just a century ago have disappeared. In the United States, an estimated 90 percent of historic fruit and vegetable varieties have vanished. For example, of the 7,000 apple varieties that were grown in the 1800s, fewer than a hundred remain. Of the 8,000 known livestock breeds in the world, 1,600 are endangered or already extinct.
In agriculture, genetically weak, high-yield monocrop varieties sometimes adapt poorly to local conditions. This means crops must be sustained with large amounts of water and repeated applications of expensive chemical fertilizers and hazardous pesticides. It’s no coincidence that some of the world’s largest seed companies, including Monsanto, Syngenta, and DuPont, got their start as chemical manufacturers.
The same holds true for high-yield livestock breeds. The drive to increase production is diluting genetic diversity. Better adapted local livestock breeds are losing out to imported animals from industrialized nations, which often require expensive feed and medicinal care to survive in foreign climates.
Ninety percent (90%) of cattle in the developed world originate from six tightly defined breeds (the Holstein-Friesian dairy cow, for example). While such livestock breeds often yield more milk, eggs and meat under controlled conditions in the short term, they pose a higher risk over the long haul because they’re poorly adapted to local climates, conditions, and indigenous diseases. As a result, global meat & dairy supplies have become largely dependent on a shrinking list of breeds designed for maximum yield: for example, the Rhode Island Red chicken, the Large White pig, the Holstein cow. In short, in our focus on increasing the amount of food we produce today, we have accidentally put ourselves at risk for food shortages in the future.
The key challenge in facing this problem has been to show it's possible to increase productivity without sacrificing diversity. The use of local seeds - in combination with natural fertilizers and techniques such as intercropping - has in some cases improved yield as much as 15 percent above that of imported, high-yield varieties. Similar success stories have occurred with local indigenous livestock breeds. Keith Hammond, a United Nations expert on animal genetics, says that in 80 percent of the world's rural areas locally adapted genetic resources are superior to imported breeds.
The North American Gulf Coast Native sheep thrives in high heat and humidity and has broad parasite resistance. On the remote Orkney Islands, North Ronaldsay sheep can live on nothing but seaweed. Zebu cattle are more resistant to ticks than other cattle. In Ethiopia, small, humpless, short-horned Sheko cattle are good milk producers that withstand harsh conditions and have resistance to sleeping sickness. Finnsheep have become vital to the sheep industry because of their ability to produce large litters. The 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. 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 16 piglets (as opposed to an average of 10 for Western breeds). Uganda’s indigenous Ankole cattle (famous for their graceful and gigantic horns) can travel long distances to water sources.
When the Irish people became dependent on the potato as a food staple midway through the 19th century, they were planting primarily one prodigious variety, the Lumper potato. In 1845, spores of the deadly fungus Phytophthora infestans began spreading across the country, destroying nearly all the Lumpers in its path. The resulting famine killed or displaced millions. This lesson from history must not be lost on us today.
One response to the rapidly dwindling biodiversity in our fields has been to gather and safely store the seeds of many different crop varieties before they disappear forever. Today there are some 1,400 seed banks around the world. Researchers are also pushing for the establishment of regional gene banks to preserve livestock biodiversity.
Finally, the most precious and endangered resource that must not be lost is the knowledge stored in the minds of farmers and ranchers -- it’s very important to combine the science of plant varieties and animal breeding with local knowledge, the farmer's science.
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