Quite small cities were demographic sinks. The trick is whether they can sustain a sufficient large family “tail”. That will vary somewhat, but can cut in at quite low populations.
Human fertility is at its maximum in the late teens and early twenties, especially for women. Therefore, during those years, young men will need enough social standing to attract young women, set up a home and have children. In societies where home-building and children are delayed, birth rates fall, while those that do not have higher birth rates.
It is worth looking at the birth rate statistics for the "baby boom" period, during which the number of children per woman did not increase, but the number of marriages did.
The short answer seems to be rural living. In other words, more space, less distractions. There are things that make a difference at the margin, but it seems to start there.
There are quite a few more regional expansions. The Arabs across the Middle East to Morocco, the Germanics into the former Roman Empire, the Thais southwards, and so on. I was concentrating on the very large-scale dispersals.
A lot of later patterns of European expansion were pioneered in medieval Europe. The Venetian Empire was the first debt-funded Parliamentary Empire, for example. The Kingdom of Aragon’s administration of its Mediterranean possessions became the template for the Spanish Empire in the Americas and the Philippines. And so on.
Nice summary, thank you. „Overall, only about 1 in 17 male lineages survived this bottleneck.” How are these statistics produced? How do we know those male lineages that did not survive? And how can we count them?
Yes indeed. Basques may be more isolates than non pastoralists, though the language distinctiveness remains striking. I have added a link, given the argument has gone back and forth.
It seems like there might be something of a dispersal happening now in the migrants from the 3rd world to the Western states. It isn't obvious that such migration will have the same effect as e.g. the farmers spreading into the foragers, as it seems that the Western states might absorb the migrants, making it more akin to foragers migrating and joining farmer cultures. That remains to be seen, but it will be kind of interesting, seeing as how historically it was higher productivity, as measured in calories, peoples who disperse and displace lower productivity peoples. Arguably the pastoralists don't fit that mold, but I am not sure. It will be interesting to see if the mass migration we are seeing is more of a blip in the long term trend, or turns into a new expansion event in and of itself.
Not that I am likely to be around to see the results, but you know...
Steve Sailer calls it “the scramble for Europe”. Movement from places where folk have less capacity to where other folk have more is not what the previous major dispersals represented. The question then becomes how much contemporary movements degrade or improve the capacities of where folk are moving to.
That's a good point. It occurred to me last night that there might have been similar small migrations quite frequently in history, but we never really heard about them because it wasn't permanently recorded or they just weren't noticeable at the historic scale. I am not sure Plutarch would have mentioned if a bunch of Gauls and Alans moved down into the Empire and lived there, even if the quality of Ravenna suffered as a result. Of course, even if it had really big implications, tracking those movements wasn't really feasible at the time, so he wouldn't be able to connect the dots. I find myself curious about those sorts of things, as it seems there is definitely a border region in the population percentage, where things go from "Eh, those immigrants are fine, just a little weird" to "Ok, now this place is just a colony of their home country". I wonder a lot about where those sorts of lines might be, and what might affect the value up or down.
Ahh yes! I remember that, I was in his PhD macroeconomics class while he was working on it. Never read it after it came out though, so I will have to have a look, thanks!
A very nice presentation! I particularly like the use of BP for historic dates, much more useful than BC and AD for demonstrating human affairs over large time scales.
I'm curious about your use of Jared Diamond's research in explaining the 'out of the river valleys' section. My understanding was that there had been many strong critiques of Diamond's research methodology and framing, especially relating to his famous 'Guns, Germs, Steel' theory to explain the 'out-of-Europe' expansion.
I think these critiques have largely come from Critical Theory proponents, so is it your belief that these critiques can be ignored and that Diamond's research is largely accurate?
Diamond’s grand meta narrative in ‘Guns, Germs, Steel’ has not held up well. But the 2003 article he co-authored is a good summary of the evidence about early farming and its spread.
quick questions on cities being demographic sinks:
what is the cut off(assuming there is one). Does the rate gradually drop as towns expand, or is there a point at which fertility plunges?
I assume that there is a 'cliff' further up, given that most cities stop at 3-5 million; is that a fair assumption?
Quite small cities were demographic sinks. The trick is whether they can sustain a sufficient large family “tail”. That will vary somewhat, but can cut in at quite low populations.
Is it known what is required to sustain the family "tail"?
Human fertility is at its maximum in the late teens and early twenties, especially for women. Therefore, during those years, young men will need enough social standing to attract young women, set up a home and have children. In societies where home-building and children are delayed, birth rates fall, while those that do not have higher birth rates.
It is worth looking at the birth rate statistics for the "baby boom" period, during which the number of children per woman did not increase, but the number of marriages did.
The short answer seems to be rural living. In other words, more space, less distractions. There are things that make a difference at the margin, but it seems to start there.
Brilliant article!
I knew about all 5 of those expansions, but I never put all the piece’s together like you did.
Might I add another: the expansion of Medieval Europe:
https://frompovertytoprogress.substack.com/p/the-expansion-of-medieval-europe
There are quite a few more regional expansions. The Arabs across the Middle East to Morocco, the Germanics into the former Roman Empire, the Thais southwards, and so on. I was concentrating on the very large-scale dispersals.
A lot of later patterns of European expansion were pioneered in medieval Europe. The Venetian Empire was the first debt-funded Parliamentary Empire, for example. The Kingdom of Aragon’s administration of its Mediterranean possessions became the template for the Spanish Empire in the Americas and the Philippines. And so on.
Nice summary, thank you. „Overall, only about 1 in 17 male lineages survived this bottleneck.” How are these statistics produced? How do we know those male lineages that did not survive? And how can we count them?
This publication is a good place to start re counting lineages.
https://www.nature.com/articles/s41467-018-04375-6
A good source of the latest genetic data regarding the prehistoric dispersals is Razib Khan's substack - https://www.razibkhan.com/
In particular WRT the Basques this is relevant - https://www.razibkhan.com/p/a-language-family-of-one-a-land-beyond
Yes indeed. Basques may be more isolates than non pastoralists, though the language distinctiveness remains striking. I have added a link, given the argument has gone back and forth.
It seems like there might be something of a dispersal happening now in the migrants from the 3rd world to the Western states. It isn't obvious that such migration will have the same effect as e.g. the farmers spreading into the foragers, as it seems that the Western states might absorb the migrants, making it more akin to foragers migrating and joining farmer cultures. That remains to be seen, but it will be kind of interesting, seeing as how historically it was higher productivity, as measured in calories, peoples who disperse and displace lower productivity peoples. Arguably the pastoralists don't fit that mold, but I am not sure. It will be interesting to see if the mass migration we are seeing is more of a blip in the long term trend, or turns into a new expansion event in and of itself.
Not that I am likely to be around to see the results, but you know...
Steve Sailer calls it “the scramble for Europe”. Movement from places where folk have less capacity to where other folk have more is not what the previous major dispersals represented. The question then becomes how much contemporary movements degrade or improve the capacities of where folk are moving to.
Dole Pastoralists
That's a good point. It occurred to me last night that there might have been similar small migrations quite frequently in history, but we never really heard about them because it wasn't permanently recorded or they just weren't noticeable at the historic scale. I am not sure Plutarch would have mentioned if a bunch of Gauls and Alans moved down into the Empire and lived there, even if the quality of Ravenna suffered as a result. Of course, even if it had really big implications, tracking those movements wasn't really feasible at the time, so he wouldn't be able to connect the dots. I find myself curious about those sorts of things, as it seems there is definitely a border region in the population percentage, where things go from "Eh, those immigrants are fine, just a little weird" to "Ok, now this place is just a colony of their home country". I wonder a lot about where those sorts of lines might be, and what might affect the value up or down.
This is a good book on that subject.
https://www.sup.org/books/economics-and-finance/culture-transplant
Ahh yes! I remember that, I was in his PhD macroeconomics class while he was working on it. Never read it after it came out though, so I will have to have a look, thanks!
A very nice presentation! I particularly like the use of BP for historic dates, much more useful than BC and AD for demonstrating human affairs over large time scales.
I'm curious about your use of Jared Diamond's research in explaining the 'out of the river valleys' section. My understanding was that there had been many strong critiques of Diamond's research methodology and framing, especially relating to his famous 'Guns, Germs, Steel' theory to explain the 'out-of-Europe' expansion.
I think these critiques have largely come from Critical Theory proponents, so is it your belief that these critiques can be ignored and that Diamond's research is largely accurate?
Diamond’s grand meta narrative in ‘Guns, Germs, Steel’ has not held up well. But the 2003 article he co-authored is a good summary of the evidence about early farming and its spread.