Farmers found that transforming their environments was hard work. But in return for their chopping, plowing, weeding, draining, and fencing, they got a lot more energy and resources from the land, rivers, and forests that surrounded them, because the species they valued flourished spectacularly. That allowed the first farmers to tap more of the photosynthetic energy flowing through the biosphere. The total flow of photosynthetic energy did not necessarily increase, of course. It may even have declined as farmers removed high-productivity plants such as trees. But for farmers, the important
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