system
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human
How people would get food in a post apocalyptic world?

Hello AskScienceFiction! I've just discovered this subreddit and I'm quite thrilled of the opportunities. Especially to make our tabletop RPG settings more realistic.

The first question I would like to ask you all is about post apocalyptic worlds like from Fallout or Mad Max. I'm currently playing a hardholder in Apocalypse World and there's one thing I can't figure out : how does people manage to get food?

Do you think there's some warlord who have dozens of slaves to grow crops? Does remaining can food from our time is enough to sustain all these people? Does people need less food?

What do you think?
gpt
This depends, how long ago was the fall?

Less that 10 years - scavenging and living off the land.  Even with all of the death from the bombs dropping and the fallout, and the subsequent raids and skirmishes, there are lots and lots of people.  Every plant and animal will be eaten, grocery stores will be picked clean. Many will starve, ecosystems will collapse.

10-50 years - (assuming nuclear winter) most of the readily available food will be gone, stores will have become death traps for the desperate, the few that had bomb shelters have run out if food.  There is still some scavenging, and what is considered "edible" has drastically changed.   Bullets are more precious than life. The only non human mammal left on earth is the dog.

At this point there is somewhere between 10-30% of peak human population alive, fully half of them are now cannibals, and a quarter of the living are kept as cattle. 

Growing crops at this point is near impossible, there is scarcity in sunlight and warmth, seeds from crops have long since been devoured, trees have been stripped if bark and rot where they stand, green is now a very rare color.  Lichen, moss, mold and fungus are now the staples of humanity.  Occasionally a cache of pre-fall food is found, but soon none will be seen again.  

There are rumors though, stories that along the equator things are better, things are warmer, that there is green, and fresh food.  Or island nations that never felt the fall. There are rumors along the equator that things must be better in the US, they have all the money after all.

50-100s of years - less than 10% peak human population exists.  At the start of this era even insects have been eaten into near extinction, there is almost no life left on earth.   

Mankind travels in small packs, malnourished and falling quickly.  Cannibalism is now universal, but no longer predatory, when one member falls the rest will eat them.  There is no organized farming or harvesting, there simply is nothing to grow.

Afterwards- life begins to return, insects and plants at first, the few humans left find foraging easier, the good times have returned.  Maybe one day far in the future dogs and fish and birds will return, but for now leaves and beetles are a gift.

((Sorry this isn't great for a rpg, no mutants or feral animals after 50 years, but food would be the cause for war and torment in a nuclear winter scenario))