On the topic of the Amish, I found this article “Assortative Mating, Class, and Caste”. In the article, Henry Harpending and Gregory Cochran argue that the Amish are undergoing selection pressure for increased “Amishness” which is essentially truncation selection. The Amish have a practice known as “Rumspringa” in which Amish young adults get to experience the outside world, and some fraction of Amish youths choose to leave the Amish community and join the outside world every generation. The defection rate among the Amish has been decreasing over time. The defection rate in recent years has been around 10-15%, but was around 18-24% in the past. Because of this, your assertion that decreasing religiosity will outpace high fundamentalist population growth seems questionable.
From the article:
The Amish marry within their faith. Although they accept converts, there are very few, so there is almost no inward gene flow. They descend almost entirely from about 200 18th century founders. On the other hand, there is considerable outward gene flow, since a significant fraction of Amish youth do not choose to adopt the Amish way of life. In recent years, something like 10-15% of young Amish leave the community In the past, the defection rate seems to have been higher, more like 18-24%. Defection is up to the individual – there are no exterior barriers against Amish who want to participate in modern society. Since the Amish have very high birth rates ( > 6 children per family), their numbers have increased very rapidly, even though there is a substantial defection rate. There were about 5,000 descendants of the original 200 by 1920, and today [2013] there are about 280,000 Amish.
Regarding the implications of future demographics for Effective Altruism/Longtermism, Robin Hanson wrote this article “The Insular Fertile Future”. Robin Hanson talks about ways modern values could be preserved in light of these demographic shifts. One possible strategy to preserve modern values could be to encourage the creation of new subcultures that inherit most of their cultural elements from the dominant culture, but also have high fertility and the adaptive characteristics that insular, religious subcultures with high fertility have.
Also worth reading is Anatoly Karlin’s article series on the Age of Malthusian Industrialism, particularly the article “Breeders’ Revenge”. Karlin argues that a reverse of the demographic transition and a “breeder transition” where there is a resurgence of high fertility due to selection for “breeders” is a mathematical inevitability. Karlin also talks about how France has a fertility rate that is roughly 1.5x that of Germany, which Karlin argues may be the result of France having an earlier demographic transition than other countries, and therefore has had more time for selection for “breeders” to take place.
I think your comment does a really good job of illustrating the difficulty in determining which groups and circumstances are selecting on what traits, as the two examples of unusually strong selection on fertility that you bring up are the Amish and the French, which have been on opposite ends of fertility behavior. It’s not impossible that both of these groups are selecting more strongly on fertility than everyone else, but it is somewhat counterintuitive.
I agree that the Amish are selecting on something, but that something isn’t necessarily a preference to have more children. The paper you linked also lists “affinity for work, perseverance, low status competition, respect for authority, conscientiousness, and community orientation” as other characteristics that may be being selected for among the Amish. If the Amish are being selected for ~conformity and community orientation rather than desire to have more kids irrespective of circumstances, then if the circumstances change at the community level (for example, if it becomes more difficult to purchase farmland, as is already happening to the community in Lancaster County, or if the Amish stop being exempt from the requirement that children need to stay in school until they are 16, which some people are pushing for) then the Amish fertility rate could decline further than it already has.
The French case seems somewhat more compelling: because of contraception and norms around family sizes, the people who had larger families in France would be people who intrinsically valued larger families, and so selection would in the direction of higher fertility preferences more directly, rather than high fertility being a result of conforming to local norms. That being said, two centuries of selection in the direction of people who want kids more than average hasn’t been enough to bring French fertility above replacement, merely to above average for Europe.
On the topic of comparing French and German fertility- so far as I can tell, Karlin isn’t making any attempt to control for Muslim fertility as a component of the French total? There are probably some ultra-conservative French catholics bumping up the total, but insular French-Muslim communities by themselves could explain the French case in roughly the same way as the Amish.
Also, FWIW, the lower rates of Amish defection over time might not necessarily reflect genetic changes (although that’s also possible.) The larger external secular society might just be getting more chaotic and repulsive over time.
I don’t think Hanson has any terribly useful suggestions for solving the secular fertility crisis, to be frank. The founding myth of our present-day secular elites is of course the holy crusade against the Nazis, which means that any serious national discussion about raising birthrates (let alone ensuring eugenic fertility) will get crushed by Lebensborn comparisons and other thought-terminating clichés.
Oh, good idea. Reverse image searching resulted in me finding the same version claiming that it’s 2007 data. So that’s maybe partially reflecting differences in how people responded to the financial crisis in particular?
Decided to find some TFR data from Eurostat and recreate this map for some more recent years. The France-Germany gap has been decreasing in visual saliency: 2014 is still pretty visible but but 2019 is less so (though there is still some aggregate TFR difference between France and Germany). Data doesn’t go far enough back for me to be able to check the original map but it doesn’t seem particularly implausible.
On the topic of the Amish, I found this article “Assortative Mating, Class, and Caste”. In the article, Henry Harpending and Gregory Cochran argue that the Amish are undergoing selection pressure for increased “Amishness” which is essentially truncation selection. The Amish have a practice known as “Rumspringa” in which Amish young adults get to experience the outside world, and some fraction of Amish youths choose to leave the Amish community and join the outside world every generation. The defection rate among the Amish has been decreasing over time. The defection rate in recent years has been around 10-15%, but was around 18-24% in the past. Because of this, your assertion that decreasing religiosity will outpace high fundamentalist population growth seems questionable.
From the article:
The Amish marry within their faith. Although they accept converts, there are very few, so there is almost no inward gene flow. They descend almost entirely from about 200 18th century founders. On the other hand, there is considerable outward gene flow, since a significant fraction of Amish youth do not choose to adopt the Amish way of life. In recent years, something like 10-15% of young Amish leave the community In the past, the defection rate seems to have been higher, more like 18-24%. Defection is up to the individual – there are no exterior barriers against Amish who want to participate in modern society.
Since the Amish have very high birth rates ( > 6 children per family), their numbers have increased very rapidly, even though there is a substantial defection rate. There were about 5,000 descendants of the original 200 by 1920, and today [2013] there are about 280,000 Amish.
Regarding the implications of future demographics for Effective Altruism/Longtermism, Robin Hanson wrote this article “The Insular Fertile Future”. Robin Hanson talks about ways modern values could be preserved in light of these demographic shifts. One possible strategy to preserve modern values could be to encourage the creation of new subcultures that inherit most of their cultural elements from the dominant culture, but also have high fertility and the adaptive characteristics that insular, religious subcultures with high fertility have.
Also worth reading is Anatoly Karlin’s article series on the Age of Malthusian Industrialism, particularly the article “Breeders’ Revenge”. Karlin argues that a reverse of the demographic transition and a “breeder transition” where there is a resurgence of high fertility due to selection for “breeders” is a mathematical inevitability. Karlin also talks about how France has a fertility rate that is roughly 1.5x that of Germany, which Karlin argues may be the result of France having an earlier demographic transition than other countries, and therefore has had more time for selection for “breeders” to take place.
I think your comment does a really good job of illustrating the difficulty in determining which groups and circumstances are selecting on what traits, as the two examples of unusually strong selection on fertility that you bring up are the Amish and the French, which have been on opposite ends of fertility behavior. It’s not impossible that both of these groups are selecting more strongly on fertility than everyone else, but it is somewhat counterintuitive.
I agree that the Amish are selecting on something, but that something isn’t necessarily a preference to have more children. The paper you linked also lists “affinity for work, perseverance, low status competition, respect for authority, conscientiousness, and community orientation” as other characteristics that may be being selected for among the Amish. If the Amish are being selected for ~conformity and community orientation rather than desire to have more kids irrespective of circumstances, then if the circumstances change at the community level (for example, if it becomes more difficult to purchase farmland, as is already happening to the community in Lancaster County, or if the Amish stop being exempt from the requirement that children need to stay in school until they are 16, which some people are pushing for) then the Amish fertility rate could decline further than it already has.
The French case seems somewhat more compelling: because of contraception and norms around family sizes, the people who had larger families in France would be people who intrinsically valued larger families, and so selection would in the direction of higher fertility preferences more directly, rather than high fertility being a result of conforming to local norms. That being said, two centuries of selection in the direction of people who want kids more than average hasn’t been enough to bring French fertility above replacement, merely to above average for Europe.
Do you know which year the map from Breeder’s Revenge that you linked is for? I don’t see a year on it, but it shows more départements at above replacement than the paper that I’ve found on Recent Demographic Developments in France, which has a map for 2015. Note that the country-wide TFR of 1.96 shown below has declined a bit since then, reaching 1.86 by 2019, and 1.83 in 2020 and that non-immigrant TFR is even further below replacement. While I think it’s plausible that TFR in France will start going up again in the near future, it’s also quite plausible that it won’t.
On the topic of comparing French and German fertility- so far as I can tell, Karlin isn’t making any attempt to control for Muslim fertility as a component of the French total? There are probably some ultra-conservative French catholics bumping up the total, but insular French-Muslim communities by themselves could explain the French case in roughly the same way as the Amish.
Also, FWIW, the lower rates of Amish defection over time might not necessarily reflect genetic changes (although that’s also possible.) The larger external secular society might just be getting more chaotic and repulsive over time.
I don’t think Hanson has any terribly useful suggestions for solving the secular fertility crisis, to be frank. The founding myth of our present-day secular elites is of course the holy crusade against the Nazis, which means that any serious national discussion about raising birthrates (let alone ensuring eugenic fertility) will get crushed by Lebensborn comparisons and other thought-terminating clichés.
Not every country has a political myth about the fight against the Nazis. So one of them might eventually take up Hanson’s suggestions.
I did a reverse image search on it, and I found a map that seems to have the same data for France and Germany that was posted in early 2014.
Oh, good idea. Reverse image searching resulted in me finding the same version claiming that it’s 2007 data. So that’s maybe partially reflecting differences in how people responded to the financial crisis in particular?
Decided to find some TFR data from Eurostat and recreate this map for some more recent years. The France-Germany gap has been decreasing in visual saliency: 2014 is still pretty visible but but 2019 is less so (though there is still some aggregate TFR difference between France and Germany). Data doesn’t go far enough back for me to be able to check the original map but it doesn’t seem particularly implausible.