[JumpCrisscross]

> resources were plentiful for hundreds of thousands of years

While they were plentiful. We chose agriculture because it means your entire tribe not dying of starvation because of minor variations in the local environment.

[DoubleDerper]

... and this tribalism led to the violent assembly of contiguous land and hoarding of resources to the alienation of everything/everyone outside the tribe. This pattern evolved into our modern system.

If local environments began to change, then your nomadic tribe moved along rather sitting around waiting to die. Birds fly south for the winter.

[JumpCrisscross]

> then your nomadic tribe moved along rather sitting around waiting to die

Which sucks if you’re injured when the migration must occur. Or if you migrate incorrectly. The evidence we have is for periods of plenty followed by harrowing narrowing of the population. These events are few in between and globally notable in the agricultural era (Bronze Age collapse, fall of Rome, et cetera).