One of the most persuasive utilitarian arguments for protecting wild biodiversity involves the “portfolio effect” — just as a diversified portfolio of stocks tends to be more stable in the face of market fluctuations, maintaining a variety of species in an ecosystem can provide insurance against loss of the natural services it provides (such as food production, water purification, crop pollination) in the face of changing environmental conditions. There is evidence for such a portfolio effect in marine fisheries, for example.
There is now concern that we need to apply this same approach to agriculture. From TreeHugger:
“In a U.N. Food and Agriculture Organisation (FAO) report released earlier this week at a conference held in Interlaken, Switzerland, agricultural scientists warned that more robust and better-adapted local livestock breeds in developing countries were losing out to imported animals from industrialized nations. The report suggests that there could be serious effects on future food security worldwide, while also emphasizing the need to determine ways to slow what one researcher is calling a ‘livestock meltdown’.”
The problem is the classic one of putting all one’s eggs in the same basket. The FAO study surveyed farm animals in 169 countries and found, for example, that 90% of the cattle in the developed world originated from only six breeds. While such livestock breeds imported from industrialized countries 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 climate, conditions, and indigenous diseases.
Like the big-box stores eating up Mom and Pop’s enterprises across the American landscape, the globalization of livestock breeds in recent decades is endangering the diversity of domesticated animals and plants, and the insurance they provide in a rapidily changing world. Rare breeds have unique traits that adapt them to the climatic conditions and diseases of the local environments in which they evolved. Maintaining a variety of livestock thus maintains a supply of diverse livestock traits that may become especially valuable as environments shift under changing climates. For example, the New Scientist reports:
“over the longer term, the imported breeds may not cope with unpredictable environmental change or outbreaks of indigenous disease. For example, many experts predict that Uganda’s indigenous Ankole cattle, famous their graceful and gigantic horns, could be extinct within 20 years because they are being rapidly supplanted by Holstein-Friesians. Yet, during a recent drought, farmers who had kept their Ankole were able to walk them long distances to water sources, while those who had switched to the imported breeds lost their entire herds.”
The FAO estimates that 20% of cattle, goats, pigs, horses and poultry are endangered by the adoption of high-yield western animal breeds. “There is a livestock meltdown under way across Africa, Asia and Latin America. Valuable breeds are disappearing at an alarming rate,” said Carlos Seré of the International Livestock Research Institute.
What to do? Seré called for creation of gene banks to store semen, eggs and embryos of farm animals. Although such gene banks already exist for livestock and crops in the developed world, there are still none for Africa. In addition, he suggests that farmers should be encouraged to maintain a diversity of breeds, it should be easier for farm animals to cross national borders with their owners, and scientists should create “landscape genomics”, that can help predict which breeds perform best under the particular environment conditions oif different regions.