The inevitable rise of Amish machines

By Razib Khan | January 14, 2011 1:58 pm

About 20 years ago I lived for a year in a rural area where Amish were a common feature of country roads and farmers’ markets. My parents, being Muslims, would sometimes buy chickens from the local Amish and slaughter them according to halal. We had a relationship with a particular family. They were nice people, though I have to admit that their chickens were a bit tougher than I was used to. In many ways the Amish lived predictably parallel lives from the “English” (we referred to them as “Dutchees”), but they’d always pop up from the background in unexpected ways. Amish don’t seem to have a problem with modern medicine, so we’d run into them at the hospital sometimes. Whenever my father saw an Amish fruit or vegetable stand on a country road he’d pull over, because they’d often let us sample a bit before we purchased (we always purchased watermelons from the Amish for this very reason). It’s been a long time, so I haven’t thought about the Amish in much depth. Living on the West coast you don’t run into their kind very often (I don’t recall ever running into Amish on the West coast in fact). But it turns out that the number of Amish in the United States of America has more than doubled in the past 20 years. Their population went from 123,000 in 1991 to 249,000 in 2010. The fertility of the traditionalist Old Older Amish is 6.2. Here’s the Old Older Amish fertility rates in an international perspective:

Fertility rate, 2005-2010
Niger 7.19
Guinea-Bissau 7.07
Afghanistan 7.07
Burundi 6.80
Liberia 6.77
Congo 6.70
East Timor 6.53
Mali 6.52
Sierra Leone 6.47
Uganda 6.46
Angola 6.43
Chad 6.20
Old Order Amish 6.20
Somalia 6.04
Burkina Faso 6.00
Yemen 5.50
Pakistan 3.43
Bangladesh 2.74
Mexico 2.21
USA 2.05
Germany 1.36

ResearchBlogging.orgAssuming current rates of increase, there should be 7 million Amish in 2100, and 44 million Amish in 2150. I don’t believe these numbers will pan out. I will explain why later in detail, but first, let’s look at the paper from which I extracted these statistics and projections. Religion, fertility and genes: a dual inheritance model:

Religious people nowadays have more children on average than their secular counterparts. This paper uses a simple model to explore the evolutionary implications of this difference. It assumes that fertility is determined entirely by culture, whereas subjective predisposition towards religion is influenced by genetic endowment. People who carry a certain ‘religiosity’ gene are more likely than average to become or remain religious. The paper considers the effect of religious defections and exogamy on the religious and genetic composition of society. Defections reduce the ultimate share of the population with religious allegiance and slow down the spread of the religiosity gene. However, provided the fertility differential persists, and people with a religious allegiance mate mainly with people like themselves, the religiosity gene will eventually predominate despite a high rate of defection. This is an example of ‘cultural hitch-hiking’, whereby a gene spreads because it is able to hitch a ride with a high-fitness cultural practice. The theoretical arguments are supported by numerical simulations.

Let’s be frank: some of this is “no shit.” “Provided the fertility differential persists” is a major central assumption of their argument. The paper is full of mathematical models, simulations, and inferences from those models tweaking the parameters. It also uses both haploid and diploid frameworks of inheritance, as well as placing the argument in a broader evolutionary framework of how religion could emerge and spread. You can read the whole paper online because it is open access.

The meat of the argument corresponds well with Eric Kaufmann’s Shall the Religious Inherit the Earth. Being a article in a journal it obviously isn’t going to be as empirically “thick” as the Kaufmann book. Instead the authors take some of Kaufmann’s empirical insights and turning them into a more rigorous quantitative system; an analytic engine for more precise prediction. Of particular importance, Shall the Religious Inherit the Earth generally worked with the assumption that religion was a cultural trait, and that its success was dependent on heritability of culture. Here the authors suggest that a predisposition toward religiosity may be rooted in genetic factors which are heritable. This adds a major twist: even with high defection rates from fecund religious groups, if religiosity is heritable many secular people will inherit a predisposition toward religion or religious modes of thought.

Below are the primary tables and illustrations.

As you can see, the big picture is this: religion wins! Assuming…. And what are the assumptions?

1) Religious people have higher fertility. This is true!

2) Religiosity exhibits heritability. This is true!

Combine these two, and you have an excellent ingredient for natural selection to drive a trait and its underlying alleles to fixation. The question is not if, but when. But it’s more complicated than that. The author covers many of the nuances within the paper, so I don’t want to be unfair here. I’m expanding on much of what they give a nod to. For example, one can’t presume that religious people are always going to be more fertile than irreligious people. As Eric Kaufmann observed the gap is the largest in secular societies. And secular societies are very new indeed. In the pre-modern world there was very little variation in the trait value. If there isn’t variation in the trait value how is natural selection supposed to “see” the variance in genes? But just as the past is not a good guide to the present, so we should be careful about the present being a good guide to the future. Or more precisely, the medium-to-far future.

As noted within the paper religiosity as a trait may exhibit density dependence. In other words, as the proportion of the trait increases its rate of increase may decrease. This is not an unjustified assumption. Around 1955 ~5% of South Koreans were Protestant or Catholic. By 1985 the proportion had risen to ~20%. That’s factor of four growth in 30 years. In 2005, the proportion was ~30%. There has clearly been leveling off, as the exponential curve begins to look like a logistic.

A particular parameter need not be fixed in time. Many projections assumed fixed parameters, and then they allow time to extend outward toward infinite. This seems to not be a robust assumption when it is not trivial, and trivial when it is robust. To understand why, look back to the past. If religiosity is heritable at around 0.50 that is a strong signal that there hasn’t been enough positive directional selection on the genes which control variation on religiosity to exhaust variation. Traits which are very strongly associated with fitness, which to some extent religiosity is today, invariably show low heritabilities. This is because selection is so good at weeding out unfit variants when fitness differentials are great. Traits which exhibit higher heritabilities, and for a behavioral trait ~0.5 isn’t bad, it is on the same order as I.Q., may not exhibit direct fitness implication, or are being buffeted by stabilizing selection. But we don’t need to rely on what we know about the genetic architecture of traits. Secularization has been proceeding for nearly two centuries, and it has shot up only recently. Atheists have been present in the literary record since the 6th century B.C.E., starting with the Greeks, but also occurring among Chinese and Indian philosophers. Any sufficiently complex hierarchical society does seem to produce dissents from the reigning metaphysical orthodoxy. If those societies do not tolerate public and open dissent, as has been the case in the past for Christian cultures, and to some extent is still the case in the world of Islam, dissenters may simply ensconce themselves in the institutions of orthodoxy so as to obtain cover for their deviations. One of the more blatant examples of this which I stumbled upon was an 18th century French bishop, Étienne Charles de Loménie de Brienne, who was blocked from being the archbishop of France by Louis XVI because of his atheism (he was made archbishop of Sens and eventually became a cardinal, before finally openly repudiating Catholicism in 1793).

Of course just because the past can not predict the present, does not mean that the present can not predict the future. So why do I think there won’t be 7 million Amish in 2100? The culture that is the Old Order Amish exists only within the context of the current United States of America, where they are a trivial minority. Today the Amish are 0.1% of the USA’s population. Some demographers predict ~1 billion Americans by 2100. I’m skeptical of this figure, but assuming that it is correct, 7 million Amish would be 0.7% of America’s population. 44 million Amish in 2150 if the USA had a population of 1.5 billion would be 3% of America’s population. I don’t think that the Amish lifestyle can take over whole societies. It isn’t economically scalable (I doubt it’s religiously scalable, but I will avoid a digression into then nature of very radical Protestantism and its repeated failures in Europe). The Amish could adapt, as the New Order Amish have, but then their fertility starts dropping. There are structural constraints on fertility beyond simply idealized preference. The Arab fertility in Israel crashed in the 2000s due to removal of some child benefits. People do respond to incentives. Or at least some people do. It turns out that ultra-Orthodox Jews continue to have large families because of stronger ideological commitments. But at some point ultra-Orthodox labor force participation in Israeli society will have to increase. At that point I predict that fertility will begin to drop. In Europe the incredibly high fertility of Roma minorities in relation to the non-Roma is only feasible under current economic surpluses of those societies. As the proportion of Roma increase the parameters resulting in incentives toward higher fertility will shift, both for the Roma, and for the society in which they are embedded. The authors make a nod to the idea that religion may have spread through group selection: but this is also an argument for why very fertile and religious groups such as the Amish and Roma will reach their “limits to growth.” If they persist in their atypical lifestyles their host societies will simply collapse. Or at least restructure in a fashion to make extremely high endogenous growth of minorities impossible.

Before I move on to a big picture “far future” implication, I want to address the issue of genetic architecture. The paper operates with a monogenic model. That is, there is a “God gene” which controls religiosity and irreligiosity. This is for reasons of tractability of the model. In broad brushes it doesn’t really matter if the trait is controlled by variance on 1 gene, or 1,000, for the main portion of their argument. But reality is more than just their model. Religiosity is heritable, which suggests it has many genes controlling most of the variance. Like many behavioral or psychological traits “religion” is somewhat a fuzzy category, and the competencies which produce religious phenomena are almost certainly implicated in many other core cognitive functions. The ability to represent entities, gods, which you’ve never seen, and have superhuman powers, leverages a host of human-specific mental skills. Not only that, but these abilities may exhibit variation from person to person. The cognitive psychologist Paul Bloom has observed that American atheists are somewhat atypical. If the traits which combine to produce religiosity and irreligiosity are correlated with a host of other traits, then these correlations may serve as a break on the margins which would prevent one “morph” from driving another out of the population. The authors note that one way irreligiosity may survive us through heterozygote advantage of those with a religious allele and an irreligious allele. But, they argue that “…heterozygote advantage is merely a theoretical possibility and there is currently no evidence to support it.” There are some theoretical reasons to be skeptical of heterozygote advantage being common. But this is not the only way that stability could be preserved on a trait.The authors are only operating within the monogenic framework, a framework whose existence is contingent on tractability of the model for their own purposes! The reality is that religiosity is probably polygenic, and there may be constraints of correlated response and frequency dependencies on the margins of many of the other traits controlled by the same genes. Bloom notes that atheists exhibit some psychological deviancies (correctly to my mind). But in a society deviated sharply toward the religious side you may start seeing other sorts of problems as well in terms of the mental state of those at the extreme end of the tail of the trait distribution.

Finally, what about the idea that selection dictates that fertility should bounce back after the demographic transition? R. A. Fisher outlined this model in The Genetical Theory of Natural Selection. The authors don’t address directly the heritability of fertility, but if the biological or psychological traits which predispose one to large families are heritable, then over time those traits will spread in the population. The demographic transition is very new in an evolutionary time scale. Arguably the first population to go through the transition was that of France in the early 19th century, with Britain next. These assumptions drive Robin Hanson to predict a Malthusian future:

But as long as enough people are free to choose their fertility, at near enough to the real cost of fertility, with anything near the current range of genes, cultures, and other heritable influences on fertility, then in the long run we should expect to see a substantial fraction of population with an heritable inclination to double their population at least every century. So if overall economic growth doubles less than every century, as I’ve argued it simply must in the long run, income per capital must fall over the long run, a fall whose only fundamental limit is subsistence; we can’t have kids if we can’t afford them.

Hanson’s argument is that eventually population growth will catch up with economic growth, as it has for all of history. The reason that we live in an age of affluence is not just economic growth. It is that the more wealth a society has today, the lower the population growth rate is, meaning that per capita wealth is increasing as the growing pie is not eaten up by more mouths. This is abnormal for all of human history, and in fact all of the biological domains. Populations tend to exhibit long term equilibrium with their carrying capacity. The key is long term. Some biological populations go through booms and busts every few generations. For humans the process may run over centuries. There was a massive ramp up of European population right up until 1300. This squeezed peasants on the margin. But the Black Death of the 14th century drastically reduced aggregate population, resulting in a situation of land to labor surplus. Not only did this change the structure of European society (with labor shortages there had to be a modification to feudal arrangements; there weren’t enough serfs to go around, so some landlords would steal labor via inducements toward better treatment, more freedom, and even pay), but the median health and diet of the peasant improved. It took a few centuries, but eventually the Malthusian grind swallowed up the surplus land which had been freed up by the Black Death. Only the lift off of the past two centuries, the concomitant speed up of economic growth and collapse of births per woman, has been the exception to this overall pattern.

So the big question is: are we simply living in a transient, like the peasants of the 15th century? In the long run everything is a transient. And, there are structural changes which mean that the past may not be a good guide to the future. The emergence of multicellular life was a revolution in the parameters of diversification of this planet’s biosphere. The arrival onto the scene of a protean cultural animal, our own species, was also a revolution in terms of the shocks which an organism can induce upon the biosphere (though not as much of a shock as oxygen producing cyanobacteria). Finally, the shift toward exponential economic growth over a few generations was also a radical change from the past. Five years ago I read The Robot’s Rebellion: Finding Meaning in the Age of Darwin. The argument within that book is presented that modern humanity in has the ability, the choice, to break free from the iron laws of the past. We need to be careful about glib projections. I think there is still a high probability that the vast majority of the existence of this universe until final heath death or inflation will be characterized by the ubiquity of von Neumann machines. But between then, and now, may be a long time indeed. Until the iron laws of evolution, and ultimately the cosmos, snap their jaws shut we may have the opportunities to choose between many paths. The painting we project upon that palette of time may be diverse, detailed, and unpredictable.

Citation: Rowthorn R (2011). Religion, fertility and genes: a dual inheritance model. Proceedings. Biological sciences / The Royal Society PMID: 21227968

Image credit: Magnus Manske

CATEGORIZED UNDER: Culture, Data Analysis, Religion
  • Uncle Al

    Religious groups have high fertility because women therein have little choice but to be (good) mothers. Let women escape from Kinder, Küche, Kirche and it all goes to Hell.

  • jason

    Why would von Neumann machines necessarily be more competitive/efficient than human beings, who have done a pretty good job of replicating in recent millenia? rgds

  • Razib Khan

    Why would von Neumann machines necessarily be more competitive/efficient than human beings, who have done a pretty good job of replicating in recent millenia? rgds

    can’t utilize space. and we “waste” a lot of energy on stuff that’s not directly tied to replication.

  • jason

    I wonder. Replication is a pretty complex activity. Maybe human lack of focus is also associated with advantages. Bacteria don´t seem to waste much energy or space. Obviously they are extremely successful, but they are also very small and we´re still here too. Von Neumann machines sound like enormously complex, multi-cellular bacteria, of a sort which haven´t been able to evolve.

  • Razib Khan

    Von Neumann machines sound like enormously complex, multi-cellular bacteria, of a sort which haven´t been able to evolve.

    don’t think they need to be that large or complex. though who knows how the engineering would work? since they aren’t filling up the whole universe, they’re not inevitable.

  • ohwilleke

    Religiousity isn’t very content specific, but the forces that are driving increased secularism are content specific.

    The forces that are driving secularism are to a great extent driven by scientific and historical knowledge that makes specific religious doctrines and metaphysical concepts untenable. The psychologically atypical skeptics may have led the shift, but this is just because they are early adopters of this kind of thing and this doesn’t imply that the meme won’t grow among people who aren’t early adopters.

    My anticipation is that as existing metaphysical belief systems fall into disfavor (as polytheism and animism have in most of the world in the past), that new forms of religiousity (spirtuality without religion in the dating website parlance) will emerge and take their place. Maybe transhumanism will catch on. Maybe it will be some sort of quantum mysticism or deep ecology. Who knows? But, something will fill the gap with similar effects.

  • Joe

    Although there is a long term correlation between rising wealth and rising fertility, there has still been a secular increase in living conditions over the last few millenia. I’ve seen you discuss the ideas from “farewell to alms” here before, but the evidence doesn’t always support it.

  • Michael Blume

    Thank you very much the sound blogpost. As a scholar in the field – and one of the sources cited by Rowthorn -, I dare say that you got the main points. Let me just add that religious behavior – behavior towards superempirical agents – is thought to date back at least to burials and offerings, later ritual places and cave paintings etc. at least in the lower Paleolithic. As an example, we are having numerous female fertility (!) figurines, spanning the time of some thousand generations. And we know from contemporary hunters and gatherers (i.e. !Kung San) that they enjoy higher chances to choose their numbers of offspring and are showing individual variances in no. of children and religious participation. As any other biocultura trait, religion is having an evolutionary history. And, well, that’s what Darwin assumed from the start, right!?

  • megan

    Hardly post but lurk on interesting topics.
    Mr. Blume said what I was thinking about ‘religiousness’ or belief in a superior being or aura to worship has been central to human thinking since early humans. So this study is seemingly narrow in what it thinks is ‘religiosity’ behavior that is lacking and now somehow being spread anew by higher birthrates of more fundamentalist believers in a religion to supposedly take over. This definition seems to only define as those spreading or harboring ‘relgiosuity genes’ as the extremely rigid belief systems with behavioral controls on both sexes when it comes to sexuality and when, who and how based on a ruling by a supreme being.

    The other thought is if the study was trying to trace older cultures into the hypothesis, no one mixes in the fact in many ancient cultures women did have control of their bodies and birthrates in support of their cultural religious belief systems. Were those type of societies sampled by this study for birthrates trying to make a statement about births over time/eras?

    Many documented studies have shown natural herbs studied, used and grown by women in ancient cultures all throughout the Mediterranean and SW Asia (really in many cultures worldwide) were either prevented pregnancy or were abortifacients. Later the newly expanding religions with their differing cultural religiousity, stopped supporting it with new decrees and dictums of what women could or shouldn’t do in terms of sexuality, Example being the rising Roman Church deemed competing religiousity practices (European tribal) ‘pagan/heretical/witches’. (Birth Control in the Ancient World March/April 1994 Nat’l Geographic)

    If that would be factored into a larger worldwide data study view of human breeding/sexual practices, birthrates and expansion vs resources, cultural changes and acquired wealth and stability there in, would be very interesting requiring exhaustive data, details and input and therefore susceptible unfortunately to bias, I would think.

    In addition, I think the large bloom of births post WWII as having been due to relative overall peace worldwide and the great expansive use of a seemingly endless energy resource to create goods and grow food, ie petroleum. Tied to scientific break through in medicine and production methods, it was a boon to allow more viable births ending in success and longer lived progeny to then produce again in a short time.

  • AG

    Jared diamond’s book `Collapes’ had made good point. Amish like religious group was new in history. They all reached their limit at some point.

  • AG

    I tried to say is `Amish like religious group was not new in history”

  • Michael Blume


    Thanks for the comment. There are two points in evolutionary studies of religion that might be of specific interest to your thoughts:

    1. Women seem to form the majority among the memberships of all grown religious denominations, as i.e. the data from the Swiss census have shown. They are also showing higher levels of religiosity and spirituality in respective studies. In contrast, the non-religious are mainly and the outspoken atheists dominantly male. Combined with other indications (such as paloearchaeological findings, the higher life expectancy of women and the role of mother-mothers in the upbringing of children and grandchildren etc.), there is growing support for the notion that early religious traditions and communities might have been formed by women.

    2. Although you are right that women had – on average – far more power in pre-agrarian religious traditions, these were fertility traditions, too. Even among contemporary neo-paganisms such as Wicca et al., life, love and births are cherished as part of the sacred course of nature.

  • AH

    “Religiosity is heritable, which suggests it has many genes controlling most of the variance.”

    I don’t see why this suggests that there are any genes controlling religiosity. Speaking a specific language is highly heritable but no one is suggesting that there are English or Mandarin language genes. When people propose that hugely complex human behaviors like religiosity are gene heritable, the burden is really on them to show us the genes. Otherwise it’s nothing more than speculative non fiction, not science.

    I am very skeptical that religion has any kind of genetic neurobiological basis beyond the more general genetic neurobiological basis for language. Religion is basically a metaphysical philosophy with a bunch of politics mixed in. It seems to me that if you have language and enough intelligence, the metaphysics is going to naturally develop out of an interest in figuring out how the world works, and that the dominant political groups in the culture are going to decide what the dominant metaphysical philosophy is going to be. No need to look to biology for something that can be explained through a cultural lens alone.

    I also suspect that cultural changes due to technological progress, particularly in bio-medicine, will be the most important factors in determining what future demographics looks like.

  • Razib Khan

    I don’t see why this suggests that there are any genes controlling religiosity. Speaking a specific language is highly heritable but no one is suggesting that there are English or Mandarin language genes. When people propose that hugely complex human behaviors like religiosity are gene heritable, the burden is really on them to show us the genes. Otherwise it’s nothing more than speculative non fiction, not science.

    you’re retard. i mean it’s heritable, not inherited

  • coldequation

    “In Europe the incredibly high fertility of Roma minorities in relation to the non-Roma is only feasible under current economic surpluses of those societies. As the proportion of Roma increase the parameters resulting in incentives toward higher fertility will shift, both for the Roma, and for the society in which they are embedded. The authors make a nod to the idea that religion may have spread through group selection: but this is also an argument for why very fertile and religious groups such as the Amish and Roma will reach their “limits to growth.” If they persist in their atypical lifestyles their host societies will simply collapse. Or at least restructure in a fashion to make extremely high endogenous growth of minorities impossible.”

    I agree, but it’s interesting to think about what this really means. How are you going to stop the Roma from growing?

    No more welfare, no more housing, food, and medical care as “rights.” Their standard of living drops to the point that their population growth rate is around 0%, because that’s all they can afford..

    Or no more fertility as a “right” – there would have to be an explicit zero-population growth enforced on the Roma, or else feeding them would become unsustainable, as you say.

    Either way, that’s the end of the modern liberal program, in which everyone has the right to do whatever they want with their reproductive organs, and it’s the government’s responsibility to take care of those who can’t take care of themselves. Anyone who fundamentally disagrees with this position today is an extremist, practically a Nazi. Even those who oppose the welfare state say they want to discourage dependency, not let people die. Yet the line of reasoning taken in this post says it’s unsustainable.

    What goes for the Roma goes for the Chassids, the FLDS, or any high-fertility group that takes advantage of public assistance (I believe the Amish don’t partake, though I’m not sure about that).

  • megan

    @AH says “I don’t see why this suggests that there are any genes controlling religiosity. “

    Whether it can be replicable in further studies, there has been genetic/behavioral research studies linking possible genetic traits in animals/nature for tendencies to altruism in group/species survival success by thinking about success of other as connected to self in some instinctive matter. Another study about genes affecting brain structure and development to encourage belief in outside supernatural forces affecting reality to enhance predicting social actions (okay I made that up to replace, ‘belief in higher beings/god(s)’ positted in the recent ‘God gene’ theory).

    Those types of genetic predispositions can be inherited and expressed but as with many things, culture and nurture affects the strength or direction it is shown, if at all, by individuals. Looking at the myriad of societies humanity has formed and evolved over time balancing individual and groups interactions based on core philosophies that seem to have been generated from brain structured interpretations of reality, (if one accepts those new newly researched hypotheses,) makes it seem there is a constant ebb and flow in expansion and growth of any particular outlook or cultural leaning with in the human species as a whole.

    As we become more connected planetwide, trying to find and work a common system of governance is why the UN and many of the largest regional governmental bodies are constantly in flux and conflict as people worry only one version will abolish or circumvent the existence of other forms. PS, I’m not a genetic/behavioral/statistic Biology PhD but just one of the very curious, self-reader and interested in all forms of science and technology disciplines and their connections. All my IMHO. Thanks for letting me post. {LOL, and I stay at the Holiday Inn}

    I hope to read the good resource books Khan had previously listed in regards to human economics over the ages. After having taken a few college course in international politics/policy for a political science degree, one of the most interesting papers I found that is still available online posits a very large overall view of human growth overtime in a way that is similar to observing chemical processes or biological cultures such that that detailed descriptions of smaller eras easily shift and fit into it’s framework without arguing right/wrong or most meaningful.

  • Razib Khan

    coldequation, your inference seems plausible. over the long run it seems inevitable; systems come back into the equilibrium. the rub is what “long run” means. with europe’s welfare states in stress already, i think there’s a high probability that the TFR’s of roma & somalis will start to come down.

    megan, please refer to me as “razib” :-) the previous commenter didn’t know what heritability was.

  • Mark

    “What goes for the Roma goes for the Chassids, the FLDS, or any high-fertility group that takes advantage of public assistance (I believe the Amish don’t partake, though I’m not sure about that).”

    They try very hard not to. In the Elkhart/LaGrange county settlement in Indiana, most Amish males were employed in RV factories prior to the recession. When they got laid off, they had to ask special permission from their bishops to receive state benefits, which was given very grudgingly. It’s not at all usual.

    I don’t see why there couldn’t be 7 million Amish in America in 2100. They would still be a very small percentage of the population, and since their tendency is to disperse and form new settlements they won’t dominate any one state or region. Some Old Order Amish groups have adapted to economic changes (mostly by leaving behind small-scale farming in favor of cottage industries, construction businesses and factory work) without experiencing significant drops in fertility. The Swiss Amish in Adams County IN and Missouri have the lowest percentage of farmers and the highest levels of fertility (8+ per woman) of any Amish group. I do think there’s a limit to their growth, but I would put it at somewhere in the tens of millions.

  • Razib Khan

    cottage industries, construction businesses and factory work)

    do you think the the niche for these areas would be large enough to support 7 million workers in 2100? have you thought in detail about the nature of economic changes, and shifts toward mechanization in manufacturing, and the possibility that at some point in the 21st century construction will actually move away from being so labor intensive? (probably through better ‘manufactured homes’)? there are “retro” “slow” niches where the amish will always be able t flourish; people willing to pay labor intensive premiums, like they do with painters enough though everyone can take digital camera photos. granted, some of the obstacles that the amish will face are going to confront a lot of the non-”knowledge” sector labor force. but the amish identity as a group, and probably their high fertility, is contingent upon an attachment on more archaic economic systems and arrangements which still have some purchase today. so u have 23 times more amish + a smaller labor intensive sector.

  • Mark


    My list was not meant to be exhaustive but to illustrate that the Amish have successfully adapted to changing economic considerations in the past fifty years. It used to be that in order to be Amish, one had to be a farmer; today, farming is a minority occupation in most church districts.

    Many Amish churches draw a distinction between the use of certain technology during the course of business, where computers and such are allowed, and the use of technology in the home, where they are strictly forbidden. Amish businessmen are often allowed to take adult vocational courses as needed despite the fact that they otherwise shun higher education as too worldly. So their approach to technology/education is more versatile than it might appear, at least among the more progressive groups. Obviously, as contact with the outside world increases, outside influences will increasingly seep in, but the switch from farming to factory work coincided with an increase, not a decrease, in the retention rate from around 60% to close to 90% in most church districts, so, at least for the time being, contact with the outside world appears to be strengthening Amish identity.

    Also, there is the “ultraconservative” element. About 10% of Amish churches are so defined and these groups, which unsurprisingly have the highest fertility and retention rates, focus on farming and self-sufficiency. The Swartzentrubers are the largest group and they are famous for this. These groups also seem willing to push into other countries with different levels of economic development in order to preserve their agricultural lifestyle: a recent issue of The Budget (the Amish newspaper) reported on Amish land scouting expeditions in Mexico.

    I do agree that economic constraints will curtail Amish population growth in the long run, and I think projections of 40+ million Amish are silly and will not come to pass. I wouldn’t be surprised if their population topped off at around 10 – 15 million, spread throughout the Americas like their Mennonite brethren, however, given the versatility of the more progressive groups and the doggedness of the more conservative ones.

  • Clark

    Do we know the Amish fertility rate over time? It would seem that if there are only 200,000 that the rate would have had to be much lower in the past (even accounting for emigration out of Amish communities). The only stats I could find were on the wiki page that had them as 5000 in 1920 with a population increase every 8 years varying between 50 and 30%. Which is pretty remarkable if you think about it. I recognize there are other complexities (such as the relation to the Mennonites). However it would seem that they will soon reach a population such that the growth rate decreases significantly. Either due to breakoffs or some other social change. Historically (at least according to the Wiki) there’s been a long history of breakoffs from the Amish that then lose their Amish identity over time.

    It’s interesting comparing the Amish to the Hutterites. Over 125 years the Hutterite population went from 400 to 42,000.

  • Mark

    The fertility rates were comparable in the past. There was a mild increase in the middle of the last century as Amish access to health care improved (and infertility decreased to pretty much zero), then a mild (but I think somewhat greater) decrease alongside the exodus from farming. Something like 7 to 8 to 6, overall.

    It isn’t just that defection rates for individuals were higher in the past; it was also a lot more common for whole sects of Amish people to switch to some form of Mennonite back when the various Anabaptist identities were solidifying in this country in the early 20th century and before.

  • pconroy

    IMO, the Amish population will continue to grow, but as others have noted, maybe the bulk won’t be in the US, but elsewhere in 150 years.

    I still remember vividly the shock of being on a jungle river cruise through Belize – about 13 year ago, when tourism was just getting started in that country – reggae and soca type music playing, and the Afro-Belizean tour guide languidly pointing out alligators and parrots; then turning a bend in the river, to see 4 ultra-blonde boys, dressed identically in blue overalls, fishing from a jetty, then seeing well ordered poultry and dairy farms carved out of the jungle. It seems that they had arrived 20 years earlier and in that time had corned the egg, chicken and most of the dairy market in the country.

    I think you’ll see some Amish continue to embrace technology grudgingly, like using car-battery powered video gaming consoles, and slowly assimilating to US norms, with a lag time of decades, but many will move to places where their farming expertise is needed and appreciated. I’d imagine they will find their way to South America, and Africa – Eastern and Southern – and maybe even Russia, Ukraine or Siberia.

  • Razib Khan

    haven’t had time to follow up, but thanks for the detailed exposition mark. i appreciate it.

  • Steven Colson

Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

Gene Expression

This blog is about evolution, genetics, genomics and their interstices. Please beware that comments are aggressively moderated. Uncivil or churlish comments will likely get you banned immediately, so make any contribution count!

About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at


See More


RSS Razib’s Pinboard

Edifying books

Collapse bottom bar

Login to your Account

E-mail address:
Remember me
Forgot your password?
No problem. Click here to have it e-mailed to you.

Not Registered Yet?

Register now for FREE. Registration only takes a few minutes to complete. Register now »