S1 : Among the momentous watersheds through which human beings have passed since their appearance over 100,000 years ago, none has been more profound in its consequences than the shift to agriculture.
S6 : Unfortunately, such transformations disrupted delicate natural balances as humans sought enhanced control over their new modes of subsistence.
P : They did this by purposefully transforming landscapes with their agricultural fields and pastures.
Q : They lived much like the way in which their own hominid predecessors had lived for millions of years, as integral components of the Earth’s ecosystems.
R : However, with the invention of practices of agriculture, these new farmers and herders began manipulating their surroundings to an unprecedented degree.
S : Before that, for countless generations, nearly all humans had lived as hunters and gatherers, dwelling together in small, stable, nomadic bands that operated in close harmony with nature.