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Nobody knows exactly when or where agriculture began. But scientists now believe that it began 8,000 years ago or more when people discovered that the wild grass seeds that they threw away along with other garbage in waste piles grew well and produced many more seeds to fill people's stomachs. This may seem like a small thing to modern people, but for primitive people it was a truly revolutionary discovery. Up until then they had depended for their lives on their luck in hunting, fishing and finding wild plants that they could eat. Being able to grow a part of their own food meant that starvation was no longer such a danger. As early people learned about raising crops, they came to depend more and more on farming and less on hunting to keep themselves alive. In addition to wild grasses, from which our present-day grains came, these early people learned to grow many other plants, the early forms of today's vegetables.