the return of the return of chinese clans

avner greif — of Family structure, institutions, and growth – the origin and implications of Western corporatism fame (well, famous on this blog anyway), and who is rapidly becoming one of my favorite researchers even though he doesn’t take into account human biodiveristy things (nobody’s perfect!) — and father guido tabellini have a fantastic paper out titled: The Clan and the City: Sustaining Cooperation in China and Europe.

they really get why western europe works the way it does while china works in a whole other way — except they’re missing the underlying biological reasons, of course. here’s what they have to say:

“In a clan, moral obligations are stronger but are limited in scope, as they apply only toward kin. In a city, moral obligations are generalized towards all citizens irrespective of lineage, but they are weaker, as identi…cation is more difficult in a larger and more heterogeneous group. We refer to this distinction as limited vs generalized morality.

i like that. more…

“Institutional mechanisms also differ between the clan and the city: clan enforcement mainly relies on informal institutions, whereas the city relies more on formal enforcement procedures. In terms of economic effciency, these two arrangements have clear trade-offs. The clan economizes on enforcement costs, whereas the city exploits economies of scale because it sustains cooperation in a larger and more heterogeneous community.”


where greif and tabellini get it wrong is that they believe that people become clannish or not depending on what sort of moral system they have. *sigh* which is exactly backwards, of course (i think) — a population’s moral system stems from whether they are clannish or not, not the other way around. but here’s there take on it:

Two otherwise identical societies that differ only in the initial distributions of moral traits evolve along different self-reinforcing trajectories of both cultural traits and organizational forms. Initial diffusion of kin-based morality leads to a steady state where clan loyalty is widespread, the clan provides public goods, the share of the population living in the city is small, and intra-city institutions are weak. This equilibrium captures the arrangements that prevailed in China.

“Conversely, if generalized morality is initially widespread, the organization of society moves to an opposite steady state, where strong and large cities act as the main providers of public goods, as in the evolution of Europe. Thus, to understand the different paths in China vs Europe, we need to focus on cultural differences in their respective early histories. Even if China and Europe had access to the same technologies, and neglecting the role of geography and other factors, social organizations and cultural traits evolved endogenously and mutually reinforced each other.”

yeah. almost. but, just where did the “initial distribution of moral traits” come from in the first place?

they’ve also got a lot of interesting stuff on the return of clans in china today. ruh roh:

“The persistence of cultural attitudes is matched by a striking persistence of clans as a central organization in Modern China.

“The modernization movement in the early 20th century was hostile to the clans, that were viewed as an obstacle to economic development. In 1904, the Chinese government legalized corporations with the explicit intention to foster joint stock companies. The law failed in this regard, as Li Chun explains: ‘the idea that members of the public would be invited to join one’s business and share in its control and pro…fits was indeed repugnant. On the other hand, the notion that one’s money be put into the pocket of some strangers for them to run a business was just as unthinkable’ (Li, 1974, p. 205 cited by Kirby, 1995, p. 50).

“The communist regime officially abolished the clans upon gaining power in 1949: clans’ properties were confi…scated, elders lost their legal privileges and authority, clan legal codes were no longer recognized, and the ideology of class consciousness was promoted (e.g., Huang, 1985, p. 308). Had the clans been a product of the state, they would not have survived the crackdown since 1949. If, however, clans had been a product of the coevolution of deeply held moral convictions, social organization, and institutions [not to mention biology – h. chick], clans should have persisted and reemerged following the reforms that allowed individuals to organize themselves. This is indeed what has happened since 1978.

“A county-level survey in 2000 (by Liangqun and Murphy, 2006, in Jiangaxi) documents that 70 surnames out of 99 (in 40 villages) updated their genealogies since 1981 and 41 surnames invested in their ancestral shrines since 1991 (p. 230). A 2002 representative national survey of more tham 300 villages reveals lineage activities and kinship organizations in 66 percent of the villages (Tsai, 2007, pp. 154–7). Clans resumed their role in securing property rights from predation by officials, organizing weddings and funerals, providing welfare, contributing to public projects, and promoting mutual aid arrangements (ibid). Inter-clan confl‡icts also resumed and collectively owned rural fa…rms often formally exclude non-locals (Thøgersen, 2002). About 90 percent of the 887 households that migrated to or from one of 50 villages relocated to their ‘ancestral village’ and 60 percent relocated due to inter-lineage tension (Liangqun and Murphy, 2006, p. 623).

“We quantify clans’ persistence using a random sample of 76 counties, 205 villages and 4274 individuals from China General Social Survey, 2005 (GSS05). The GSS05 asks (only) rural residents whether there is a clan organization in their community and, whether it is a surname-based or a temple-based clan organization. Although under-reporting of clan organizations is likely given tradition of suppression by the communist authorities, the census reveals 277 clan-based organizations. A clan organization almost always (90 percent) has a genealogy, a graveyard, or both. The two organizational types differ, however, in their economically-relevant assets such as land, estates (other than ancestral hall), and trust funds. Only 26 percent of the surname-based network have such an asset compared to 78 percent of the temple-based organizations (F12). On average there is 1.35 organizations per-village and one organization per 15.5 respondents. The highest number of people per-clan organization is in the eastern region (35) and the lowest is the northwest.

Almost 70 percent of the population live in a county with positive sample probability of a village having an organization and in 41 percent of the counties the village-probability of having a clan organization is at least 50 percent. In fact, clan organizations currently exist in each of China’s six regions although there are no temple-based clan organizations in the north (Figure 2, note that the northwest is a separate region) but they are particularly strong in the south-central region and, speci…cally, in Guandong, the richest province. These findings correspond to our historical discussion in which we noted the relations between out-migration from the North and the rise of clans.

“Table 5 presents the number and fraction of organizations –out of the 277 in our sample that ful…ll various functions. Most common are cooperation-promoting functions –resolving private disputes within the village and handling inter-village relations –and providing public goods in the village or the clan.

“Our online appendix also documents that the frequency and strength of clans in modern China is negatively correlated with urbanization in townships (i.e. excluding major cities), as predicted by the model. Speci…cally, data from China County-prefectural Statistical Yearbook, 2006 (YB06) and China General Social Survey, 2005 (GSS05) reveals that in the sample of 76 counties, clan strength is negatively correlated with urbanization even after controlling for such variable as education, infrastructure investment, and distance from the coast.

This re-emergence of clans is particularly noteworthy given that the reforms were not designed to foster clan organizations. Households, and not clans, were given land-use rights in the former collective farms and privately-owned businesses were permitted. Yet, kin-based and relations-based exclusive organizations have re-emerged and resumed their traditional role in supporting cooperation.”

previously: the return of chinese clans and china today… and whatever happened to european tribes?

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when in rome?

i left this in the comments here not that long ago, from Rome and its Frontiers: The Dynamics of Empire [pgs. 205-212 – links and empahses added by me]:

[I]n the later Roman Empire frontiers became softer and immigration control more lax at the same time as citizenship and ethnic distinctions within the Empire were becoming blurred. The universal grant of citizenship by the Constitutio Antoniniana of 212 AD was only a formal recognition by the state of a long process that had diminished the concept of citizenship and eroded the distinction between cives and peregrini in the provinces. By the fourth century status and wealth counted for more socially and legally than citizenship….

“To sum up, far from the homogenization of what the Constitutio Antoniniana called the patria communis, that is, the population of the Roman community, internal, social divisions became stronger. Ironically, however, the refinements of status distinctions and social divisions served as a more effective vehicle than any legal measure to allow immigrants to integrate at all levels. What mattered was not whether you were a citizen but whether you could attain equal social or economic status. In this respect, the Roman Empire of the fourth century was the reverse image of the nation-state in the nineteenth century. The juridical personality of the citizen was almost eliminated as frontier controls relaxed and as immigrants were accomodated in ever greater numbers….

“Immigrants provided substitutes for rural recruits, thus leaving agricultural workers on the land to increase state revenue, since they increased the capitation tax and added extra income through the system of adaeratio, which bought them exemption from the military levy. There clearly were concerns in the imperial chancellery for the tax regime and for the rents from imperial estates, which was reflected in contemporary legislation….

“These fiscal and economic benefits to rural production coincide with the concern expressed by the Gallic panegyricists about agri deserti and high taxes, and hence their praise for ‘so many farmers in the Roman countryside’, both as immigrants and as returning prisoners… The essential point, however, is that … immigrants were officially perceived as good for the economy by bringing down the price of food and by servicing local markets through increased production.

“Whether the peasants of the Gallic countryside felt the same pleasure at the fall in market prices is another matter, and it may have provoked resentment. If modern experience is any guide, there is a sharp difference between economists, who calculate that immigrants are essential to economic growth, and popular opinion, which always believes that immigrants are undesirable because they depress the labor market. But there is no evidence to show that there was institutional, social discrimination against foreign-born workers, once settled inside the Roman Empire….

the author also refers to [pg. 212]:

“The long history, since Augustus [r. 27b.c.-19a.d.], of frontiers open to foreign migrants, and the even longer history of liberal access to citizenship and Romanization…”

gee. all sounds awfully familiar (presumably the roman senators even claimed they were worried about crops rotting in the fields…).

now last night i came across this in Marriage and the Family in the Middle Ages [pg. 30]:

“[I]mpelled from their homes by cataclysms still shrouded in mystery, they [the germans] began pressing westward and southward in a series of waves climaxing in the fifth and sixth centuries. In addition to feeling pressures from behind — famine, drought, Huns — they were drawn into the Roman Empire by the magnet of an economically and technically advanced region, with its cities and villas, granaries and warehouses, shops, tools, coins, and ornaments, in a species of ‘gold rush’ (in the phrase of a modern historian). Columns of thousands or tens of thousands of Goths, Gepids, Alemanni, and other peoples from the north and east, men, women, children, and animals, filtered or flooded through the Roman frontier defenses, sometimes peacefully and by permission, sometimes violently or by taking advantage of the moments when the legions were absent contesting the Imprerial succession on behalf of their generals….

“In the later stage of the Migrations, large numbers of several major groupings — Burgundians, Ostrogoths, Visigoths, Franks — entered Gaul and Italy as foederati, or allies, by a negotiated arrangement that settled barbarian families on arable land in much the same fashion that Roman veterans had been settled in the earlier period. This episode in the Great Migrations apparently took place with little friction between newcomers and old inhabitants.**

“**Walter Goffart (Barbarians and Romans, A.D. 418-584: The Techniques of Accomodation) postulates that instead of being given lands expropriated from Roman and Gallo-Roman proprietors, many of the Germans were assigned revenues from normal taxation in the provinces in which they were settled, in return for which they garrisoned the frontiers against later arrivals.”

little friction? why? how?

i’m sure that a big part of the reason why westerners today don’t seem to be very concerned about mass immigration to their countries is ’cause times are good (or they were up until very recently). maybe something like that was also the case for roman empire days? i dunno.

but here’s something interesting that might’ve possibly affected roman attitudes (might’ve) [pg. 22]:

Even stronger than the bar to interclass marriage was the proscription against incest or marrying ‘in.’ Early Rome forbade marriage between second cousins, but over time the rule was relaxed, and even first cousins were allowed to marry. When the Emperor Claudius (reigned A.D. 41-54) chose for his fourth wife his niece Agrippina, the public was shocked, but the Senate obligingly revised the legal definition of incest, and (according to Suetonius) at least two other uncle-niece marriages were recorded. This was an exceptional case, but in revealing the flexible nature of exogamy rules it foreshadowed much medieval controversy.”

so in early rome — in the days of the republic — you couldn’t marry anyone closer than second cousins. hmmm…. i’ll have to check the dates on when the changes started to happen, and also how strong enforcement was and all that. but, interesting. very interesting!

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random notes: 08/29/12

just some random notes that i want to keep track of — and that i thought might interest some of you guys out there — but that i haven’t, or am not planning to, work into a full post — not just now anyhoo. enjoy!

the law of wihtred from the 690s:

“The Law of Wihtred is an early English legal text attributed to the Kentish king Wihtred (died 725). It is believed to date to the final decade of the 7th century and is the last of three Kentish legal texts…. It is devoted primarily to offences within and against the church, as well as church rights and theft.”

from The Anglo-Saxons from the Migration Period to the Eighth Century: An Ethnographic Perspective [pg. 216]:

“Marriage was redefined, as a consequence of the influence of the Church, in the laws of Wihtred; four chapters (Wi. 3-6) condemn illicit unions — namely unconsecrated unions, bigamous unions or unions within the forbidden degrees.”

so here we have a secular, anglo-saxon (jutish!) law from the late 600s banning cousin marriage (should be out to second cousins according to canon law at this point in time). this was in kent. this was also just at the beginning of the era when mating practices were loosened in england — right after the anglo-saxon-jutes converted to christianity. who knows how well … or for how long … the law of wihtred was enforced.

from The development of the family and marriage in Europe [pg. 144]:

“Much later this [the church’s cousin marriage ban] was reduced to the second degree [i.e. first cousins] for Indians of South American origin in 1537, for Blacks in 1897, and then for the world at large in 1917.”

the one, holy, catholic and apostolic church (gotta love the full title!) regularly offered concessions on the whole cousin marriage thing for new converts: they did so for the anglo-saxons/other germanic tribes, and again for the baltic populations. not surprising that they should also do so for native americans and africans.

i don’t know if the 1537 exemption applied to mexican/central american populations as well or just to south american indians. that’s something i need to find out.

previously: east anglia, kent and manorialism

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more on medieval england and france

sam worby refers to charles donahue jr.‘s Law, Marriage, and Society in the Later Middle Ages as “magisterial” and there’s no hyperbole in that i can assure you. at a mere 696 pages(!), it’s a very thorough examination of marriage litigation in fourteenth and fifteenth century england and, what donahue calls, franco-belgia. donahue himself describes the book as “obscenely long.” (^_^) it’s not at all! it’s just very, very complete. and very, very awesome!

donahue studied the records of five medieval episcopal courts: york, ely, paris, cambrai and brussels. and, afaict, he looked at the data from every which way possible. i haven’t read the whole thing … yet … but i’ve gleaned a couple of interesting points so far:

– apparently, there weren’t a whole lot of cases (requesting annulment or whatever) brought before the courts on the basis of consanguinity — it really seems to have been a (relatively speaking) non-issue at this point in time in england and franco-belgia;

– the types of cases brought before the courts in england indicate that there were more marriages entered into independently by the parties involved in that country, whereas in franco-belgia it seems that parents were much more involved in arranging their children’s marriages;

– property was held independently by husbands and wives in england (what property a woman brought to her marriage remained hers, although husbands usually managed those properties), while in franco-belgia the property was shared, communally, between husband and wife;

– primogeniture was the rule of the day in england, while all the kids (or all the sons anyway) inherited in franco-belgia.

the last three points are really interesting because those are the same ones made by emmanuel todd in The Explanation of Ideology, only he was referring to more modern times in england and france (1500-1900). it seems, however, that todd’s family types, and their characteristics, for these two nations — absolute nuclear family in england and egalitarian nuclear family in france — go right back to at least the 1300-1400s.

another, possibly minor, point to note — maybe it’s not important at all, or maybe it will turn out to be later — is that donahue’s “franco-belgia” seems to be more or less where early medieval austrasia was — and austrasia is significant because, according to mitterauer, that’s where manorialism got started in europe.

here are some bits from donahue:

pg. 604: “It is a characteristic, then, of English marital property patterns that husband and wife hold their property separately and of English inheritance patterns at all levels of society that one child takes his parents’ property to the exclusion of his siblings. In the Franco-Belgian regions, on the other hand, the tendency is to community property between the spouses and to partible inheritance among children….

“The Franco-Belgians, we might argue, were more concerned with their children’s marriages than were the English because under most Franco-Belgian inheritance customs, all of their children stood to inherit their property. In England, only the marriage of the heir needed to be arranged, whereas in the Franco-Belgian region the marriages of all children needed to be arranged because almost all children were heirs. Hence, we see more litigation in the Franco-Belgian region about marriage contracts because they were more common. We also see more concern with informal marriages — punishing them with automatic excommunication — but fewer informal marriages, in fact because more marriages were arranged….”

what a selection pressure!: “English inheritance patterns at all levels of society that one child takes his parents’ property to the exclusion of his siblings.” and going right back to at least the 1300s in england.

pgs. 609-610: “What we need, then, is some overarching explanation on which both the marriage practices and the property rules can be seen as dependent. The overarching explanation that I offer is both complicated and fuzzy, but it seems right now to be the most plausible: The difference we are trying to explain is a small one heightened by the litigation pattern. Many Franco-Belgian marriages were probably indistinguishable from many English ones. But the difference that produced the difference in results, I would like to suggest, is fundamental, in the sense that it goes to the very core of how people understood themselves. The legal difference are dependent on it. However strong the sense of family and of community was in England, it was weaker than it was in the Franco-Belgian region. The English, with their separate ownership system of marital property, with their winner-take-all inheritance system, with their abundant evidence of do-it-yourself marriages, with their strict attitude toward judicial separation, but with their apparent do-it-yourself system of separation, are, for the Middle Ages, an unusually individualistic people. The Franco-Belgians, with their community property, with their shared inheritance system, with their carefully planned marriages, their reluctance to hold that a marriage, particularly an informal marriage, existed, with their system of judicial separation that brought more cases before the courts but judged them by broader standards, are more communitarian. We are dealing here, we might suggest, with a cultural phenomenon that developed independently over the course of centuries and of which both the property system and the marriage cases are an expression.

i would, of course, say we are dealing here with a biological phenomenon. (~_^) i might be willing to go so far as to say a bio-cultural one, though.

“Like the property argument offered previously, this argument needs to be spelled out and qualified. The individualism of the separate ownership system of English marital property has to be qualified by the great power of the husband to manage his wife’s property while the marriage lasted and by the expectancy that each spouse had in the other’s land. The individualism of the English impartible inheritance system has to be qualified by the fact that the present holder of landed wealth had responsibilities to past and future generations in the management of that wealth, responsibilities that could, in some circumstance, be legally enforced. The evidence of English do-it-yourself marriage comes largely from court cases, and it may be that a disproportionate number of do-it-yourself marriages ended up in court. Despite these qualifications, however, and despite the fact that great variations could be achieved in the property system by private action, the core systems, the default systems, of succession and marital property in England seem to focus much more on the individual property holder than do the core or default systems reflected in the *coutumiers*. The fact that the default system of succession in England concentrated wealth in the hands of one person meant that in many families, the children who did not inherit were left to seek their fortunes, to a greater or lesser extent, on their own. Similarly, however aberrant the do-it-yourself marriages that we see in the English church court records may be, the records of all those *de presenti* informal marriages are there, and there are few, if any, like them in the Franco-Belgian regime. Similarly, there are many more records of judicial separation in the Franco-Belgian region than there are in England.

“The communitarianism of the Franco-Belgian marital property system also has to be qualified by the great power of the husband to manage the community while the marriage lasted. The communitarianism of the Franco-Belgian inheritance system needs to be qualified by the power of the current property holder in many of the customs to prefer one child over another by endowment or testament or both. The evidence of arranged marriages in the church court records needs to be qualified by the fact that many of the *de futuro* marriages in the Franco-Belgian records seem to be informal and made without much concern for family consent (consider, for example, Tanneur et Doulsot). Despite these qualifications, however, the core or default system of property in the Franco-Belgian region remains more communitarian than the English. One simply does not find many, if any, English wives seeking separation from their husbands for incurring obligations *ipsa inscia et absque eius [uxoris] proficuo*. The basic principle of inheritance remains *egalite entre heritiers*. The canonic system of marriage is modified, at every turn it would seem, so that concerns other than those of the marriage partners are considered.

“The distinction between individualism and communitarianism that we are seeking to make does not correspond exactly to the traditional distinctions in family types — joint versus stem, horizontal versus vertical, kin group versus lineage, extended versus nuclear — nor does it necessarily tell us much about authority within the family. Obviously, concern for the individual is more likely in situations where family ties are less extended and where authority within the family is weak. Too much depends, however, on the strength of the kinship ties and how the authority is exercised for there to be an exact correspondence between our dichotomy and any of the broader types of family or of authority….

“Can we go any further? Can we offer an explanation for why the English might be more individualistic than the Franco-Belgians, the Franco-Belgians more communitarian than the English? In a previous essay, in attempting to explain why the Franco-Belgians developed community property and the English did not, I suggested that after one took into account the technical legal explanations for the differences between the two regions and explanations based on the differences in the relative power and interests of lords and families, there remained an unexplained residue of variance that could only be accounted for by what I called the ‘anthropological’ explanation, a difference in attitudes toward the family, reflecting, perhaps, an historical difference in family type or structure. This difference in attitude was independent of any economic differences, for the two regions were remarkably similar economically, particularly in the thirteenth century when the difference in marital property systems seems to have emerged.”

hmmmm. what might the underlying reason for this “anthropological” difference between the individualistic english and the more communitarian franco-belgians be? my guess, of course, would be some sort of difference in mating patterns, but i haven’t come up with a whole lot of data for the medieval french yet (i’ll have to get to work on that!), so … can’t say much of anything about that possibility just now.

one social or economic difference between medieval england and the continent that mitterauer pointed out is that banal lordship did not develop in england whereas it did everywhere else in nw europe. this, i think, might have had a signficant impact on the genetic structure of both societies (england vs. everyone else in nw europe on the continent) because the banal lords controlled their subjects so much more directly — including, possibly, their mating opportunities. from mitterauer [pgs. 41, 45, & 56]:

“Most important among these transformational processes was the growth of the ‘immunities’ of ‘banal lordship’ (Bannherrschaft, seigneurie banale) that began in the tenth century. This primiarlity involved the manorial estates of the nobility…. Banal lordships of the nobility could practice jurisdictional and other rights of authority related to dues and services — including rights over subject on ecclesiastical estates….

“On one point, however, the English manorial system diverged from the continental one: banal lordship did not take hold in England….

“With the rise of banal lordship in the tenth century, these buildings [housing knights and their horses and equipment] were frequently converted to fortresses, so that they took on the particularly striking appearance of a seat of lordship. The numerous seats of noble and ecclesiastical lords demonstrated how decentralized the organization of lordship was — a pattern without counterpart in the formation of empires outside Europe. The decentralized organization of lordship contributed in turn to a certain autonomous heft shared by the peripheral regions over against the center. This would promote federalist tendencies in the later history of Europe.”

i have to admit that i don’t fully understand this banal lordship business. from what i gather, they seem to have been a middle order of lords (sort-of feudal middle managers) having power/control over a rather local population. if that’s correct, then it’s very interesting that there weren’t really banal lords in england, because that might mean that the english were that much freer to move about or to marry whomever they wanted, which seems to have been the case. if you have a system with local lords controlling what goes on in relatively small areas, then they might very well want to keep the local laborers on the land and not let them marry out very far — we actually have an example of this from the manors of eighteenth century poland.

if this is at all correct, perhaps this can (partly) account for the differences between england and franco-belgia that donahue picked up on. if franco-belgia had banal lords that restricted the population’s mating patterns and england did not — well maybe that’s part of the “anthropological” explanation donahue is looking for for why the medieval english were so individualistic while the franco-belgians were more communal and “clannish” (or “extended family-ish”).

dunno. just thinking aloud.

previously: “l’explication de l’idéologie” and traditional family systems in medieval britain and ireland and medieval manoralism and the hajnal line

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the hgdp samples again

i’ve written before (here, here and here) about the hgdp samples and the fact that there is very little to no provenance info connected to them. the problem with this, afaics, is that it’s difficult to know whether or not the hgdp samples are truly representative, in all ways, of the populations from which they came.

i was particularly concerned initially about the french (and the japanese) hgdp samples — and then i got over that — but now i’m concerned about them again. here’s why:

the hgdp samples from france are described thusly:

“France – French/various regions (relatives) – This sample from various regions of France is part of the Human Genome Diversity Cell Line Panel collected by the Human Genome Diversity Project (HGDP) and the Foundation Jean Dausset (CEPH). This sample consists of unrelated individuals and was collected with proper informed consent.”


hang on — which regions?

auvergne? where, in some villages in the eighteenth century, groups of families regularly inbred with one another? lorraine? which, in some areas, had consanguinity rates of up to 50% between 1810 and 1910? burgundy or brittany, both of which had reportedly higher cousin marriage rates in the nineteenth and twentieth centuries than other regions of france? or were the hgdp samples collected in places like central france which, historically, had much lower rates (in the range of 1-3.5%) of close marriages?

the thing is: we don’t know.

what we do know is that the hgdp sampling seems kinda biased towards unique little groups like basques and orcadians, sardinians and the adygei. which is understandable ’cause these are all interesting, unusual groups and there’s legitimate concern that their unique genomes might sorta disappear in our modern, outbreeding world, and it would be a shame to miss out on the chance to at least keep a record of all that human biodiversity.

but then i have to wonder how representative of the majority of french people are the french hgdp samples? do they truly represent “the french,” or did the samples come from some of those crazy little villages way up in the mountains? i dunno. and neither does anybody else (afaik).

and the reason i wonder is: if teh scientists are gonna do really awesome genetic studies to check for the relatedness between the members of different human populations — like runs of homozygosity (roh) studies or identity by descent (ibd) studies — i think they need to know if the samples they’re looking at are representative or not. do the results for “the french” in studies like this or this or this truly represent the average french, or do they represent some special sub-groups of mountain dwelling french?

in the most recent roh study i posted about, the “french” don’t appear to be much more in- or out-bred than orcadians or the basques, something which strikes me as odd. perhaps — perhaps — that’s because the french hgdp samples are not truly representative of the broader french population. perhaps. i don’t know. nor do the researchers.

rinse and repeat above discussion for the other samples, too.

previously: hgdp samples and relatedness and more on the hgdp samples and why i care about the hgdp samples and meanwhile, in france… and runs of homozygosity and inbreeding (and outbreeding) and ibd and historic mating patterns in europe and runs of homozygosity again

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more on anglo-saxon mating patterns

it seems like the anglo-saxons were still marrying close relatives (prolly close cousins) in the 800s, at least in some areas of england. here from jack goody [pgs. 161-62 – links added by me]:

“In England, as in Ireland, popular resistance to the marriage rules had been felt as early as Anglo-Saxon times. Lancaster comments that the frequency of defections from ecclesiastical rulings on marriage with near kin was a constant cause of complaint during this period. In 874 Pope John VIII wrote to the King of Mercia saying that fornication was rife and that men ‘presume to marry women of their own kindred’. Some sixteen years later the Archibishop of Rheims wrote to King Alfred [king of wessex] in the same vein. Sermon and legislation continued to condemn and prohibit the widespread ‘incest’ (Lancaster 1958: 240).”

perhaps this is why in the 900s-1000s there were such strict secular laws prohibiting cousin marriage in at least some of the anglo-saxon kingdoms?

previously: anglo-saxon mating patterns

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anglo-saxon mating patterns

pre-christian tribal anglo-saxons (and jutes, et al.) married their close cousins with some regularity (who knows what the actual frequencies were). this is evidenced by the fact that when the anglo-saxons in england converted to christianity in the 600s, they were given exemptions from the church’s cousin marriage bans (because they had married their cousins prior to converting). augustine of canterbury corresponded with pope back in rome regarding the whole issue of the cousin marrying anglo-saxons [pgs. 34-37]:

“Bede tells of some of the problems involved in converting the pagan English. He explains how after Augustine, the first archbishop of Canterbury, arrived in 597, he sent messengers back to Pope Gregory at Rome seeking advice on certain current questions, including ones relating to marriage….

“[T]he Letter of Gregory provides us with some very valuable evidence….

“Four of the nine questions on which Augustine asked advice from the Pope had to do with sex and marriage…. Augustine’s fifth question was more complicated and more revealing: ‘Within what degree may the faithful marry their kindred; and is it lawful for a man to marry a step-mother or a sister-in-law?’

“Pope Gregory’s reply clearly indicates the change that Christianity had brought to Rome and presumably to the other countries of western Europe. ‘A certain secular law in the Roman State allows that the son and daughter of a brother and sister [fzd/mbd marriage], or of two brothers [fbd marriage] or two sisters [mzd marriage] may be married. But we have learned from experience that the offspring of such marriages cannot thrive. Sacred law forbids a man to uncover the nakedness of his kindred. Hence it is necessary that the faithful should only marry relations three or four times removed, while those twice removed must not marry in any case, as we have said….’

“Since a special dispensation had to be given to those who had contracted such unions before conversion, it is clear that the practices of close marriage (presumably to cross-cousins, and possibly, as in Rome, to parallel cousins, at least to the father’s brother’s daughter) and of marriage to the widow of the brother or father (though not one’s own mother) must have been common in English, and indeed German, society. But they are now forbidden, the arguments against them being framed partly in physical terms (the likelihood of infertility) and partly in religious ones (on grounds of incest…).”

so, by the time they were all converted (700-800s?), the anglo-saxons in england shouldn’t have been marrying their close cousins anymore. the problem was, however, as it has always been — enforcement. who was going to enforce these rules, which emanated from rome, way up in yorkshire? or event kent?

because the thing was, early christian marriages didn’t necessarily have to happen in a church in front of a priest. they could do, but it was not actually required. all that was required was to abide by all the regulations (don’t marry your cousin, consent should be mutual, etc., etc.). eventually, however, over the course of the medieval period, the church did take control of marriage ceremonies, but it wasn’t until the early 1200s that marriage in a church with a priest was necessary to have a valid marriage [pgs. 146-150]:

‘In England between the seventh and the twelfth centuries the ecclesiastical authority in matrimonial questions was slowly established’ (Howard 1904: I,333). At first the Church appears only to have concerned itself with the nuptial mass but gradually it became involved both in the betrothal and in that gifta or handing over of the bride which was regarded as the essence of marriage. Finally, in the twelfth century, Peter Lombard’s annunciation of the ‘seven sacraments’ proposed that marriage be included among them….

“No public ceremony was needed [still in the 1100s] to make a marriage valid, but, in order to make it fully licit, certain procedures had to be followed….

“But while only this form of marriage was licit, other unions could be valid. The betrothal followed by intercourse became marriage, even without being solemnised in church. This being so, since men and women did not always get married in facie ecclesiae, some making their agreement at home, or in a field, a garden, or even in bed, problems often arose in proving to the satisfaction of the ecclesiastical judges that a marriage had taken place at all. Some 70 per cent of the marriages involved in cases heard in Ely between March 1374 and March 1382 took place in private surroundings. While it was doubtless the intention of most parties to follow the private with a public celebration, not in all cases did this occur….

“A better explanation of the Church’s attitude to such marriages [clandestine marriages] would seem to be based on the difficulties it experienced in imposing its will on the forms and patterns of marriage at all levels, whether that of the nobility as described by Duby, or in the more popular milieu of Ely. Only with the Council of Trent [1545-63] did the Catholic Church finally manage to impose its authority in this sphere by invalidating marriages that had not been performed in public before the parish priest, a notion that was later followed in Protestant circles….

“The Church had recognised the problems created by ‘private’ marriages long before the Council of Trent. From late in the twelfth century local attempts were made to ensure that the priest made a public proclamation of a proposed marriage sufficiently far in advance to allow anyone to make an open objection to the union. The procedure became generalised under canon 51 of the Fourth Lateran Council [1215] when the priest was required to announce the marriage and to investigate the possibility of impediments. In England the announcement took the form of reading the banns on three Sundays. In fact this procedure appeared to have more effect on the enforcement of the prohibitions than on the publication of the marriage itslef…. In his study of a register of court cases from fourteenth century Ely, Sheehan remarks that it was possible to get round the banns not only for ‘the large group that avoided religious ceremonies entirely’ (1971: 239), but even for many who wished to have the blessing of the Church; the latter simply went to a distant parish where people were not aware of any impediment to their marriage….

When a marriage was discovered to have taken place outside the parish, the parties were liable to punishment….. If a couple did not wish to run the risk, it did not have to undergo a church wedding at all. In Ely such uncelebrated marriages were frequent at this time. Out of 101 unions mentioned in the register, 89 were of this ‘irregular’ kind. Of course it was precisely these marriages that were likely to come before the court, for the large majority of disputes were not about divorce but were demands to recognise a marriage as valid; pleas of annulment were infrequent, as were references to parental consent….

[I]n general the impediments arising from ‘blood’ marriage and ‘spiritual’ ties, which according to many commentators, offered an easy way out of marriage, formed the basis of relatively few disputes in the medieval English courts (Helmholz 1974: 77ff). When the Fourth Lateran Council reduced the prohibited degrees from seven to four in 1215, it also tightened up the proof necessary to establish these ties for legal purposes. While we know that the nobility treated these restrictions with little concern, obtaining dispensations when they were needed, surviving court records give little indication that the prohibited degrees presented any major problem for the bulk of the population. Hemlholz argues that the actors accepted the rules, and sees evidence of this in the large percentage of marriages which were contracted outside the village (about 50 per cent)….

so, for four hundred years — from, say, 800 to 1200 — the enforcement of the close cousin marriage ban in england by the church was probably pretty patchy. the ban was there — and people obviously knew about it (since some of them tried to get around it) — but enforcement by the church was definitely not 100%.

still, helmholz apparently argues (i haven’t read him yet) that, by and large, ordinary englishmen and women largely abided by these regulations.


well, they might have done so for religious reasons — many may have simply wished to follow the church’s teachings in order to stay in god’s good books. but, there was also incentive from another direction — secular laws which backed up the church’s regulations.

in “Kinship and marriage among the Visigoths,” ausenda makes it clear that secular rulers (kings, prices) across northwest europe also issued decrees against cousin marriage, no doubt with an eye on breaking the social and economic power of clans (they weren’t the first — chinese rulers tried this as well, but they ran into the enforcement problem) [pg. 147-48]:

“Langobardic [Lombardian] laws concerning forbidden marriages also became stricter over time. Liutprand 33 [8th century] forbade marriage with the widow of a cousin, but no further prohibitions were reflected in the laws. We know, however, that more extended prohibitions were made compulsory by the Church….

This shows that both Church and State were interested in forbidding close kin marriages. Their common concern becomes clear when one bears in mind the recognized difficulty the Church had, from the fourth century onwards, in expanding into the countryside….

“In conclusion, the strenuous effort [by the Church] to penetrate the countryside entailed a long-drawn battle against traditional religion, whose vehicle was the kin group, and substituting the authority of the elders of the kin group with that of a religious elder, the presbyteros. At the same time the king’s rule was undermined by revolts on the part of the most powerful kin groups, clans or sections, whose conspiracies and murders menaced the power of the state. Thus Church and State became allies in trying to do aways with the political power of extended kin groups utilizing all manners of impositions. One of the most effective among them was to destroy their cohesiveness by prohibition of close kin marriage.” [more here.]

in parts of (all parts of?) anglo-saxon england, the secular laws prohibiting close cousin marriage were quite severe [pgs. 39-40]:

“[M]arriage to any close kin was forbidden by the Church and its proscriptions were given legal sanction by Christian monarchs. In Anglo-Saxon England the punishment for breaking these rules was very heavy, namely slavery (that is, according to the late text, Edward and Guthrum, 4, Whitelock et al. 1981), with the man passing into the ownership of the king and the woman into that of the bishop (Whitelock 1930: 111; 1981: I, 307).”

whitelock’s primary sources date to the 900-1000s, so we can say that from at least that point onwards, anglo-saxons had some powerful incentives to stay away from close cousin marriage. it’s difficult — probably impossible — to reconstruct what the actual close cousin marriage rates in anglo-saxon england were, but they must have been very low indeed after ca. 800-900s. especially when compared with other regions of europe/the world in which cousin marriage was encouraged rather than discouraged.

see also: The Development of the Family and Marriage in Europe by jack goody.

*update 08/24: see also more on anglo-saxon mating patterns.

previously: inbreeding amongst germanic tribes and more on inbreeding in germanic tribes and but what about the english?

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runs of homozygosity again

**update below**

here’s an exciting new paper!: Genomic Patterns of Homozygosity in Worldwide Human Populations. i don’t have access to the paper itself, but there are lots o’ neat figures and tables in the supplemental data [opens pdf] that relate to runs of homozygosity (roh). roh are identical stretches of dna within an individual’s genome (i.e. identical on each of the dna strands, paternally and maternally inherited). (roh shouldn’t be confused with blocks of identity by descent [ibd], which i did once! ibd blocks are identical stretches of dna as compared between different individuals, iiuc.)

recall that possessing lots of long roh indicates that one’s parents are/were quite similiar genetically speaking. that can be as a result of a couple of different genetic scenarios like (as greying wanderer has brought up a lot recently) simply being from a small sized population (i.e. having a small effective population size) and/or from regular inbreeding (consanguineous/endogamous mating). so, a population having a lot of long roh is either small and/or inbreeds a lot. populations having LOTS of short roh have probably been through some sort of bottleneck (see previous post).

in the paper i looked at in that previous post, the researchers had looked at the different roh lengths for large, regional populations like “europeans” or “east asians.” amongst other things, they had found that some of my regular inbreeders — the fbd marriage folks — had some of the highest numbers of medium and long roh, a state of genetic affairs which likely reflects their long-term close mating patterns. interestingly, the researchers had found that east asians had roh lengths similar to those of europeans across the board, something which surprised me since, at least according to what i’ve been reading, east asians (i.e. the chinese) have been inbreeding for a much longer time than europeans. one drawback of that previous study, though, was that, apart from the french, most of the european populations they looked at were peripheral groups who have had a tendency to inbreed more than my “core” europeans (see mating patterns in europe series below ↓ in left-hand column).

the new paper suffers from some of the same problems since the data come from the same sources (hgdp-ceph and hapmap phase 3 populations), so northern europeans — apart from the french — aren’t included in this paper either. (what can you do? it’s early days yet. i look forward to when there’s lots more genetic data available out there for teh scientists to work with! (^_^) )

what the researchers in this paper have done, though, is to look at both the different mean lengths of roh in each of the different populations sampled AND they looked at total numbers of roh within individuals for each population. this has, i think, drawn out some interesting differences between the populations.

first, here are two graphics from the supplmental data (linked to above). click on each for LARGER views (they should open in new tabs/windows — you might have to click on them again there to super-size them).

i’ve highlighted a handful of populations i want to focus on ’cause i know a little something about their historic mating patterns: the bedouin (as a proxy for the arabs — note that the bedouin have probably inbred more than more settled arabs); italians (not sure if they’re northern or southern italians or a mix of both — however, there are tuscans in the samples with which these “italians” can be compared); pathan or pastuns (more fbd marriage folks, like the bedouins/arabs); and han chinese (there are some northern han chinese with whom this groups can be compared). ok. here are the charts:

as you can see, the researchers have split up the roh into three classes (note that the short and medium classes here are a lot shorter than those in the paper looked at previously):

– A: 0.25-0.40 Mb (short)
– B: 0.6-1.2 Mb (medium)
– C: 0-35 Mb (long)

the interesting thing in the first chart above (Fig. S3 – Mean ROH Length for Each of the Three Size Classes in Each Population), is that the han chinese have lower means of roh length in all of the size classes compared to the other populations i’ve highlighted. in the previous study, the researchers found that east asians had similar means to europeans for all roh lengths. i found this surprising since, from what i’ve read, the han chinese have been inbreeding for a longer period of time than europeans. what might be confounding the results though, once again, is the fact that nw europeans (the outbreeders extraordinaire) are not really included in either of these studies apart from a handful of french samples.

in this latest study, both the bedouin and the pashtun, for instance, have higher means — and wider spreads — of long (class C) roh than the italians, which is what i would’ve expected since those two groups (the bedouins and the pashtuns) are, being fbd marriage folks, serious inbreeders. perhaps the reason the han chinese long roh mean is comparatively low is partly due to the fact that they historically practiced mother’s brother’s daughter (mbd) marriage which doesn’t push towards such close inbreeding as fbd marriage. still, i would’ve expected to see greater means of roh for the chinese than the italians — or, at least, around the same. not so much lower. (unless the italians practiced fbd marriage, too — or fzd marriage — but i don’t think so.)

if you look at the second chart (Fig. S4 – Total Number of ROH in Individual Genomes), however, you’ll see that, overall, the han chinese have more short, medium and long roh totally in individual genomes than any of the other three populations i’ve highlighted. both the bedouins and the pashtuns have greater numbers/wider total spread of long roh than the italians, but the han chinese have a much greater total number of long roh than any of the other three groups — three or four times as many.

but they’re, on average, shorter long roh don’t forget. (confusing, eh?!)

perhaps this is what you get when you have — as the chinese have had — a pretty good-sized effective population size for such a long time. there have been a LOT of han chinese for — wow — millennia.

so, it looks like this (in this order of inbrededness — i think):

– bedouins: highest mean, and very wide spread, of long roh; high total numbers, and widest spread, of long roh.
– pashtun: low mean, but widest spread, of long roh; low total number, but very wide spread, of long roh.
– han chinese: very low mean, and very narrow spread, of long roh; highest total numbers, and wide spread, of long roh.
– italians: low mean, and rather wide spread, of long roh; very low total number, and very small spread, of long roh.

other interesting points are that:

– the tuscans/tsi (toscani) appear to have lower short, medium and long mean roh than the generic “italian” category. however, the tuscans have lower total numbers of long roh than the “italians” while the toscani (tsi), on the other hand, appear to have a greater total number of long roh than the “italians.” while the tuscan samples and the toscani/tsi samples are from different studies (hgdp vs. hapmap), they are all supposed to be from tuscany, so it’s surprising that they’re so different. perhaps the individuals in the toscani/tsi sample were more closely related somehow?

– the northern han samples have lower short, medium and long mean roh than the generic “han” category. this would fit my general impression that historically inbreeding has been greater in southern china than in the north. however, the total number of long roh are greater in the northern han sample than in the “han” sample. not sure what that means.

don’t forget that there can be all sorts of reasons for differences in roh: inbreeding vs. outbreeding, yes, but also effective population size, population movement (migration in or out), bottlenecks, etc. i just happen to be interested in trying to pick out the effects of inbreeding/outbreeding — if possible.

**update – here are a couple of excerpts from the article (thnx, b.b.!) [pgs. 277, 279-281]:

“Size Classification of ROH

“Separately in each population, we modeled the distribution of ROH lengths as a mixture of three Gaussian distributions that we interpreted as representing three ROH classes: (A) short ROH measuring tens of kb that probably reflect homozygosity for ancient haplotypes that contribute to local LD [linkage disequilibrium] patterns, (B) intermediate ROH measuring hundreds of kb to several Mb that probably result from background relatedness owing to limited population size, and (c) long ROH measuring multiple Mb that probably result from recent parental relatedness….

“In each population, the size distribution of ROH appears to contain multiple components (Figure 2A). Using a three-component Gaussian mixture model, we classified ROH in each population into three size classes (Figure 2B): short (class A), intermediate (class B), and long (class C). Size boundaries between different classes vary across populations (Table S1); however, considering all populations, all A-B boundaries are strictly smaller than all B-C boundaries (Figure 2C). The mean sizes of class A and B ROH are similar among populations from the same geographic region (Figure S3), with the exception that Africa and East Asia have greater variability. The class C mean is generally largest in the Middle East, Central/South Asia, and the Americas and smallest in East Asia (Figure S3), with the exception that the Tujia population has the largest values. In the admixed Mexican population (MXL), mean ROH sizes are similar to those in European populations. In the admixted African American population (ASW), however, mean ROH sizes are among the smallest in our data set, notably smaller than in most Africans and Europeans.

“Geographic Pattern of ROH

Several patterns emerge from a comparison of the per-individual total lengths of ROH across populations (Figure 3). First, the total lengths of class A (Figure 3A) and class B (Figure 3B) ROH generally increase with distance from Africa, rising in a stepwise fashion in successive continental groups. This trend is similar to the observed reduction in haplotype diversity with increasing distance from Africa. Second, total lengths of class C ROH (Figure 3C) do not show the stepwise increase. Instead, they are higher and more variable in most populations from the Middle East, Central/South Asia, Oceania, and the Americas than in most populations from Africa, Europe, and East Asia. This pattern suggests that a larger fraction of individuals from the Middle East, Central/South Asia, Oceanis, and the Americas tend to have higher levels of parental relatedness, in accordance with demographic estimates of high levels of consanguineous marriage particularly in populations from the Middle East and central/South Asia, and it is similar to that observed for inbreeding-coefficient and identity-by-descent estimates. Third, in the admixed ASW and MXL individuals, total lengths of ROH in each size class are similar to those observed in populations from Africa and Europe, respectively (Figure 3).

“The total numbers of ROH per individual (Figure S4) show similar patterns to those observed for total lengths (Figure 3). However, in East Asian populations, total numbers of class B and class C ROH per individual are notably more variable across populations than are ROH total lengths.”

previously: runs of homozygosity and inbreeding (and outbreeding) and ibd and historic mating patterns in europe

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