Our dwindling food supply

http://ngm.nationalgeographic.com 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.

With a significantly reduced variety of food crops, the danger of GMOs replacing real foods becomes more pressing.

This makes it more appealing to consider self-sufficient sustainable farming in the face of a possible future mass food shortage.