Because a civil war is war happening within the same country, hence the literal name.
The majority of canals built in the United States were in the Great Lakes. That was the region.
The development of agriculture occur circa around 8000-6000 years ago. It was a time where many nomadc population begin to settle in a place, thus effectively starting the civilization as we know now. it was a huge shift for humanity and it was probably one of the most important, if not <em>the</em> most important achievement in human history.
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It was quickly accepted as the preferred food source by people living in settlements because it could be planned and organized, thus helping people reaching a balance easily and preventing them from being dependent from the results of hunt and gathering. it was a safe and sicure way to assure food for everyone.
