Answer:
lots of things made them leave
Explanation:
Drought was a big reason but also because the people weren't clean which probably caused health problems. There was also alot of pests and while animals among the area. There was also volcanos and violence happening. Archaologists were really unsure they thought they left abruptly, but now they say they were forced out because of the things that were there to endure.
Answer:
Seems like a question that doesn't have a wrong answer, but I would say a society where everyone is economically equal, just to play it safe.
Farming began about 8,000 years ago