As we've come to depend on a handful of commercial varieties of fruits and vegetables, thousands of heirloom varieties have disappeared. It's hard to know exactly how many have been lost over the past century, but a study conducted in 1983 by the Rural Advancement Foundation International gave a clue to the scope of the problem. It compared USDA listings of seed varieties sold by commercial U.S. seed houses in 1903 with those in the U.S. National Seed Storage Laboratory in 1983. The survey, which included 66 crops, found that about 93 percent of the varieties had gone extinct. More up-to-date studies are needed.

More in National Geographic September Issue 2011.

Graphic: John Tomanio, NGM staff. Food Icons: Quickhoney
Source: Rural Advancement Foundation International.

Aug. 18, 2011
John Tomanio
John Tomanio „Dvínandi fjölbreytni fæðutegunda okkar “, Náttú Aug. 18, 2011 URL: [Skoðað:Nov. 30, 2023]
Efni má nota eða vitna í samkvæmt almennum venjum sé heimilda getið með slóð eða fullri tilvitnun hér að ofan.