Fungal attacks on food supplies are concerning, but global catastrophe is not likely.
Recent commentary by Eva Stukenbrock and Sarah Gurr—published in Nature and covered by Damian Carrington in The Guardian—claims fungal attacks threaten to wreak havoc on the world’s primary foods like wheat, corn, and rice. While hundreds of fungal pathogens like wheat stem rust, rice blast fungus, corn smut, and so on, have infected crops for decades if not hundreds and thousands of years, there are good reasons to be alarmed.
Fungal pathogens become more worrisome once we consider the rise of monocultural cropping practices, warming temperatures that encourage the spread of fungi, resistance to common fungicides, and the ability fungal pathogens have to diversify their genetic makeup and travel across continents.
Viewed solely as an issue of biology, we should be concerned. These fungi continue to grow, probably at an increasing rate, and will destroy food and lead to famine if left unchecked. Stukenbrock and Gurr claim that fungi destroy so much food that 600 to 4,000 million people could have had 2,000 calories per day for an entire year, rather than the nearly 3000 calories a day which is now the global average. Such a claim does not necesarilly mean anyone starved; however, it does mean there is less food.
Stukenbrock and Gurr’s call to increase awareness, scholarly attention, and public funding should be heeded from this point of view.
Fortunately, there are genuine reasons to think such concerns are overblown. First, severe famines have been declining throughout the 20th century, along with falling rates of malnourishment. The Green Revolution with the help of Norman Borlaug helped spur these trends and, relatedly, economic development. While fungal pathogens might negatively influence food supplies, they probably have smaller effects than the positive effects of increasing agricultural productivity.
Second, the world is not composed solely of biological systems. Market and price systems help coordinate the decisions of buyers and sellers and channel resources to their highest valued use. As goods become relatively scarce and/or more dear, for example, market prices rise, which encourages consumers to economize and search for cheaper substitutes and producers to increase available supply.
Given local and global food markets, people voluntarily provide food for others who are willing to pay the price, which channels food and nutrients to people who value such goods. Food prices, for wheat, corn, rice, and so on, rise and fall with countless changes in consumers’ desire to obtain food and producers’ willingness to sell food. As market food prices reflect these changes, they signal changes in relative abundance and scarcity.
Whether farmers face pests, adverse weather, physical conflict, and whether consumers change their diets or have higher incomes, food markets and prices adjust. We recognize the relevance of such factors in numerous contexts, from rising demand due to population growth to various positive and negative supply shocks, increased productivity, droughts, pests.
Returning to the Green Revolution, for example, wheat, rice, maize, potatoes, and cassava yields increased by 208 percent, 109 percent, 157 percent, 78 percent, and 36 percent, respectively, between 1960 and 2000. This increased food supply lowered prices by 35-65 percent.
Not surprisingly, people change their consumption of these goods as prices change. Consumers who value wheat less than the prevailing market price will search for cheaper substitutes, including millet, quinoa, einkorn. Perhaps, they might make their existing stock of wheat last longer or go without it entirely. Also, wheat farmers and prospective wheat farmers who observe the higher price will tend to increase production.
As wheat prices have increased over the last couple years due to the conflict in Ukraine and adverse weather, people have consumed less wheat and more of cheaper alternatives, like rice in Indonesia and tapioca in Brazil. But, as shown below, global wheat prices also remain relatively stagnant and they can fall.
That people make choices and can substitute towards cheaper items is an underappreciated point for those concerned about fungal pathogens. While fungi might increase prices of some goods, people can purchase relatively cheaper ones. This suggests they might be less likely to suffer from food shortages.
Economic logic and market systems do not eliminate the threat fungi pose, but they clarify when and where we might face genuine problems. It seems likely that markets will respond to the threat of fungal attacks in ways we can anticipate and in ways that help coordinate market participants. As pathogens develop and destroy crops, supply falls and prices rise, all else equal. Such factors, however, are not the only relevant factors, some of which might lower prices.
Hayek calls the market system a marvel in that if it were consciously designed—it is not—it would be counted among the greatest inventions, “one of the greatest triumphs of the human mind.” Local and global food markets provide a similar marvel and will likely withstand subsequent fungal attacks.