Each tribal polity can only occupy one hex at a time (not a strictly realistic assumption, but we can simply say that there are no other polities of note in the area). Carrying capacity $K$ decreases as resources in the hex are used up. Once $K$ converges with the population size, the tribe must either move or split to maintain balance. When a tribe leaves, the area begins to recover.
There are certain hexes with a high desirability which serve as generators: once a tribe reaches one, there's never any incentive to leave, and so more and more tribes are spun off as a result. When I add discoveries, these will become probable Ur-city locations.
The desirability issue is particularly obvious when a saturation point is reached. I've not yet added oceanic migration, so the tribes bounce around from place to place like so many gas molecules in a closed container.
(I feel compelled to point out that 1500 years is a pretty long time. In 519 AD, the Kingdom of Wessex was founded. In fantasy, we typically deal with deep-time related to people groups - thousand year reigns are not unusual. In real life, empires are generally much more temporary.)
This simulation progresses much faster than the "civilized" simulation, due to code rewrites and the fact that these tribes aren't doing much other than running around and eating all the wildlife.
In these first runs, I noticed that the raw desirability, which is the main selection factor, is far too high for areas that humans (the only race I'm working with for exploratory purposes) would normally avoid, such as deep tundra. So that will need to be fixed. I also want to add a mechanism for tribal warfare, if there is a some greener grass on the other side but it's occupied already.
You're right in that rpg/fantasy histories tend to be too static or long term compared to Earth's history. Yet you should also consider that our species has been around for 10s of thousands of years; most of that time has been as hunter gatherers and we pretty much filled up the world by the time civilizations began to rise. When the first agricultural societies began to form in Mesopotamia and Egypt and India and China there were no uninhabited places. People were everywhere. So yeah, your simulation should cover huge spans of time but large civilizations should only emerge very late in that timespan.
ReplyDeleteOn that note, it might be a good idea to let tribes spread across oceans too, though maybe only following ocean currents. That way you could have societies all over the world even if you only use a single starting point on a single continent.
Delete> There are certain hexes with a high desirability which serve as generators: once a tribe reaches one, there's never any incentive to leave, and so more and more tribes are spun off as a result.
ReplyDeleteI'm reading about foraging societies right now (The Lifeways of Hunter-Gatherers – The Foraging Spectrum by Robert L. Kelly — it's a really good book, there's plenty of modelling in there that should be translatable into a simulation in a pretty straightforward manner) and this seems a mite unrealistic.
The book heavily implies that people becoming sessile is more a function of population density than resource availability – and even where it is about resource availability, it is not about just absolute resources available at a given spot, but having way more resources at that spot than in any surrounding areas – otherwise, even if the current spot has enough resources to support the population, moving to another spot and foraging there is cheaper, since after a while movement cost plus foraging cost after the move is lower than foraging cost at the current spot.
Thanks for that resource! That's good feedback, I'll check out that book and see if I can incorporate those concepts.
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