system
Given the following post, respond as if you're commenting on Reddit:
human
[Borderlands 1, 2, TPS] Ecology of Pandora and Elpis

It seems that all the native wildlife on Pandora and Elpis all appear to be omnivorous but despite the ample sunlight there appears to be little vegetation. 

Similarly, on Elpis, there's no Energy food chain at all to support Torks, Shuggaraths or any of that. So with exception of feeding on Scavs and human flesh, what supports all these ecosystems? What are people eating? How does Sanctuary feed it's population?
gpt
In the beginning, food was largely imported from agri-worlds, and those shipments are still going on - they're all that's really left of Pandora's economy, because everyone has to eat.  Remember, even *scout* ships in the Borderlands are the size of cities; a proper *commerce* ship can set down entire grain silos to feed a city of millions for a year before moving on.

With cheap food, people move out, forming settlements all over Pandora.  But when the mines dry up, the cheap food dries up.  Offworld food becomes a luxury good, because supply and demand dictate as such (limited supply, meeting intense demand).  Then, the Vault sets up its meme broadcast and it's all over for commerce for the greater portion of Pandora.  People rob the trains, if they're lucky, or trade for it if they're not.  A few farmers try to eke out an existence - the few farms you stumble across in Borderlands 2 - but what few things grow well grow *underground*, away form the scalding sun.  Coincidentally, this favors creatures with huge claws to dig for them - thus, the bullymong, the skag, those tentacle-based creatures that pop up at the worst possible time.

As part of his greater plan to become the richest, most powerful man in the history of ever, Jack was trying to change that.  The Wildlife Exploitation Preserve used domed ceilings to turn away baking sunlight and high walls to prevent windblown erosion - and within, it could easily be called an arable paradise, where captured moisture eventually returns to the soil to help things grow.  And the city of Opportunity was going to have ag-domes - feeding the populace *fresh* fruits and vegetables, not as a rare once-in-a-lifetime treat but as their daily bread and butter, emotionally making them dependent on Jack.  Jack's plan was a lot like Luthor's - buy the rights to land (Lex bought extraterratorial seascapes, Jack bought dead mined-out planets) nobody wants, make it valuable overnight (Luthor using kryptonite to create solid land, Jack using dropships of hyperion loaders to digistruct walls and farms), and call it a day.  (And oh - by controlling the Warriors, he had a way to *make* planets become land that nobody wanted.  Gotta love playing both ends!)  But in the end, we all know what happened to those ag-domes once the Vault Hunters came into town.

So get used to potatoes (key calorie source), beets (sugar source), parsnips, rutabegas, and carrots; they're the only edible things that grow well on Pandora itself.  If you do well, your diet will be supplemented with offworld grains, with the occasional dropship offloading luxury canned fruits and vegetables.  Even Tina's beloved crumpets are made of potato flower.