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.
The idea that Horace Bushnell was associated was religious liberalism.
The definition of subsistence farming is "the farmers focus on growing food to feed themselves and their families.The typical subsistence farm has a range of crops and animals needed by the family to feed and clothe themselves during the year. Planting decisions are made principally with an eye toward what the family will need during the coming year, and secondarily toward market prices."