Right. Something that modern society is good at is smoothing out random variations. After a local catastrophe, the rest of the country (or, sometimes, the world

Right. Something that modern society is good at is smoothing out random variations. After a local catastrophe, the rest of the country (or, sometimes, the world) will lend you a helping hand nowadays. But back then, your whole tribe would get wiped out. Similar for non-life-threatening events. Food input decrease in your area? You barely notice it in the somewhat higher prices, because society is routing food to you from other places. But your hunter-gatherer ancestors would be hungry for days or weeks. We're better adapted for a harsh, variable environment, and it's funny how our cozy, temperature-controlled dwellings are causing a whole host of new issues.