First up in discussing worldbuilding is a bit of Required Reading. As far as I’m concerned, Guns, Germs and Steel by Jared Diamond is essential reading for anyone interested in doing worldbuilding work, be it secondary fantasy worlds or alternate history worlds or even other planets with interstellar worldbuilding.
The central premise in GG&S is this question: if all human societies are, more or less, equally clever, why did European and Asian societies advance faster and thus achieve domination over the globe? What advantage did they have? The only answer possible is those societies had a geographical advantage. They lived in a region where agriculture and animal domestication could thrive, which then allowed them the free to develop other advances, culminating in the Guns, Germs and Steel that would give a culture the ability to dominate over another.
So the first important lesson to derive from GG&S is this: no culture has ever advanced technologically without first moving past the hunter-gatherer stage to agriculture. In order for any member of society (or, more specifically, a significant chunk of that society) to be able to spend their days fiddling with things, they can’t be worried about where their next meal is coming from. If your food source isn’t stable, your society isn’t growing. I won’t name names, but there is a rather noted series from a highly regarded genre author in which a the depicted society has advanced supercomputers while still being hunter-gatherers. This is patently ludicrous.
The blessings of geography boil down to having good natural resources that can be domesticated. Diamond posits that over 13,000 years of trial and error, there simply isn’t a species of plant or animal that humans didn’t TRY to domesticate. (He also notes the key difference between domesticated and tamed. You can have, say, a tamed lion. You can’t have a domesticated one.) The plants and animals that are the most important in our society NOW, and have been for centuries, are the ones that have stood the test of time for their usefulness to society.
What does this mean for worldbuilding? For starters, if you have a society that’s more technological and socially advanced, then it has to have a solid history of agriculture and animal domestication. Your society should have some Key Crops that forms the backbone of the calories consumed by the people. Think about what they might be. Here and now, there are only a dozen species that make up 80% of the tons of food grown: wheat, corn, rice, barley, sorghum, soybeans, potato, manioc, sweet potato, sugar cane, sugar beets and bananas. Same with animals. There are only fourteen Large Domesticable Mammals: sheep, goats, cattle, pigs, horses, Arabian camels, Bactrian camels, llama/alpaca, donkey, reindeer, water buffalo, yak, Bali cattle and mithan. Something to note: of those animals, all but one were native to Europe & Asia. South America had llamas, while North America, Australia and sub-Saharan Africa had none.
Of course, you can make up different crops and domesticated animals that form the backbone of your society. Especially with secondary worldbuilding, they can be unique crops to your world. But they should share aspects that the successful crops and animals from our world. Your advanced societies will be shaped by the plant and animal resources they had available due to geography. And a less advanced society should specifically LACK those initial geographical resources to give reason why they didn’t develop.
Good stuff! I tend to have this same sort of issue with video games. The agricultural base just isn’t there to support the large towns! Silly, but the inconsistency totally takes me out of the game.
I wonder if those inconsistencies come, in part, from so much of modern society being separated from the agricultural base. Let’s face it, most of us don’t worry about where our next meal is coming from, let alone put a lot of real thought into where it really CAME from.