st. augustine on outbreeding

here is st. augustine from his The City of God Against the Pagans on outbreeding (and a bit on inbreeding). it’s a little “I’m My Own Grandpa” in places, but augustine’s basic point is that it’s good that people marry out (eg. avoid marrying their close cousins) because in doing so, they increase the number of connections which they have with other individuals — and if everyone in a society does this, there will be larger and broader networks of individuals with common goals and interests, etc., etc., all of which will “bind social life more effectively” and, hopefully, help create the city of god here on earth as much as possible. never mind the possible evolutionary effects.

st. thomas aquinas refers to these passages in his Summa Theologica in his discussion on the merits of outbreeding (but maybe not too much outbreeding!).

source: Augustine: The City of God Against the Pagans, Books 1-13 [pgs. 665-667]:

“16 – That the present law pertaining to marriage between blood-relations could not apply to the men of the earliest times

“After the first marriage of the man made from the dust and his wife, created from the man’s side, the human race had need of the union of males and females in order to multiply itself by begetting offspring. But there were then no other human beings apart from those who had been born of the first two. Therefore, men took their sisters as wives. In ancient times, this was acceptable, because done under the compulsion of necessity; now, however, it is damnable because forbidden by religion. For affection is now given its proper place, so that men, for whom it is beneficial to live together in honourable concord, may be joined to one another by the bonds of diverse relationships: not that one man should combine many relationships in his sole person, but that those relationships should be distributed among individuals, and should thereby bind social life more effectively by involving a greater number of persons in them. Thus, ‘father’ and ‘father-in-law’ are the names of two different relationships; and so the ties of affection extend to a greater number of persons when each has one man as his father and another as his father-in-law. When brothers and sisters were joined together in marriage, however, the one man Adam was compelled to be both father and father-in-law to his sons and daughters. So too, his wife Eve was both mother-in-law and mother to her children of both sexes; whereas if there had been two women, one as mother and the other as mother-in-law, the bond of social affection would have operated more widely. Again, a sister also, because she had become a wife as well, united two relationships in herself, whereas if these had been distributed between two people, one a sister and the other a wife, the number of persons bound together in the closeness of fellowship would have been increased. But this state of affairs could not exist when the only human beings were brothers and sisters, the children of the first human couple. It could exist only when there was a plentiful suppoly of women who could be wives without also being sisters. Then, not only was there no longer any need for brothers and sisters to marry; it also became unlawful for them to do so. For if the grandchildren of the first human beings, who by that time could have taken their cousins as wives, were joined in marriage to their sisters, there would then not have been two relationships united in one person, but three; which relationships should be distributed among different individuals, in order to unite a greater number in the closness of affection. For the marriage of brothers with sister would then have made one man the father, father-in-law and uncle of his own children. By the same token, his wife would be the mother, aunt and mother-in-law of their shared children. And the children themselves would be not only brothers and sisters and spouses to one another, but also cousins, as being the offspring of brothers and sister. If, however, each of these relationships were assigned to a different individual, they would then connect nine people instead of three to each of them. For one man would have one person as his sister, another as his wife, another as his cousin, another as his father, another as his uncle, another as his father-in-law, another as his mother, another as his aunt, and another as his mother-in-law; and so the social bond would extend not merely to a small group, but ever more widely, to connect a large number more closely together.

“We notice also that, as the human race has increased and multiplied, this rule has come to be observed even among the impious worshippers of many false gods. For although their perverse laws may permit brothers and sisters to marry, their actual custom is better, and they prefer to shun the freedom to do this. In the first ages of the human race, it was generally permitted to take a sister in marriage; but this practice is now so much deplored that it is as though it could never have been lawful. For what achieves most in influencing or offending human sensibilities is custom; and, in this case, custom restrains us from immoderate lust, so that men are right when they judge it wicked to disregard or transgress custom. For if it is wicked to pass beyond the boundary of one’s own property out of greed for possession, how much more wicked is it to subvert a moral boundar out of lust for sexual intercourse! We have also found that, for moral reasons, marriages between cousins are rare even in our own times, because, even though such marriages are permitted by law, the degree of kinship involved in them is only one step away from that of brother and sister. Such marriages were not prohibited by divine Law, and they have not yet been forbidden by human law either;[82] but abhorrence was felt for an act which, though lawful, bordered on the unlawful because marriage with a cousin seemed to be almost the same as marriage with a sister. For cousins are called brothers and sisters even among themselves, because of the closeness of their blood relationship, which is almost that of full brothers and sisters.

“To the patriarchs of antiquity, it was a matter of religious duty to ensure that the bonds of kinship should not gradually become so weakened by the succession of the generations that they ceased to be bonds of kinship at all. And so they sought to reinforce such bonds by means of the marriage tie before kinship became too remote, thereby calling kinship back, so to speak, as it fled. Thus, when the world was now full of people, although they did not like to marry sisters with whom they had either a father or a mother or both parents in common, they nonetheless liked to take wives from within their own family. Who would doubt, however, that the state of things at the present time is more virtuous, now that marriage between cousins is prohibited?[83] And this is not only because of the multiplication of kinship bonds just discussed: it is not merely because, if one person cannot stand in a dual relationship when this can be divided between two persons, the number of family ties is thereby increased. In addition, there is present in man a certain sense of honour, which is both natural and laudable, which prompts him not to direct towards a woman whom he is bound to respect and honour as a kinswoman that lust — and lust it is, even though necessary for procreation — which, as we see, occasions shame even within the chastity of marriage.

“[82] Marriage between cousins was, in fact, prohibited by the Emperor Theodosius I (see Ps. – Aurelius Victor, ‘Epitome de caesaribus’, 48; Ambrose, ‘Epist.’ 60,5. This is a fact that Augustine seems to remember in the next paragraph. See also Plutarch, ‘Quaest. Rom.’, 108.

“[83] See n. 82.”

previously: st. augustine and st. thomas aquinas and thomas aquinas on too much outbreeding

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the canonical family tree

following up on a reader request, here is an extended family tree for ya with names (boy, it's HARD to pick names for kids!).

everything is from the point-of-view of “jack” (ego). i went for double-barrelled names in order to give some sort of hint as to any given individual’s relationship to jack. so, his father’s brother (his paternal uncle) is “frank bob.” and his father’s brother’s daughter (his paternal first-cousin) is “frances betty” (see what i did there?).

here they all are (click on charts for LARGER images – should open in new tab/window):

now, in father’s brother’s daughter marriage (i can see your eyes glazing over already!), jack marries his uncle frank’s daughter, cousin frances. in a society where this is a common practice (eg. arab world), they do this over and over again, although maybe not in every generation. if it were every generation, it would look like this:

so, all of the jacks marry their cousins frances betty. see how the lineage keeps folding back in on itself? this is some close inbreeding.

also, see the left side of the canonical family tree? — where uncle mike and aunt martha are? mom’s brother and sister? that side of the family tree doesn’t really exist in an fbd system, ’cause mom’s brothers and sisters are ALSO dad’s paternal cousins. in an fbd system, the left side of the family tree should really be over on the right side. (*facepalm*) maybe i’ll try to draw that one day. it’s no wonder that most peoples in the world consider fbd marriage to be too incestuous — interesting that most people figured that out and avoid it.

now, here’s mother’s brother’s daughter marriage, the most common variant of cousin marriage and the most common form found (traditionally) in china:

again, all of the jacks marry their mother’s brother’s daughter (mbd) — mary beth. but this time, dad is NOT related to mom’s side of the family via his patrilineage. this is a sort-of inbreeding, but not so close as fbd marriage above. not always within the same lineage. mom’s brother, mike, is probably married to a woman from some other lineage, so cousin mary beth is not so closely related to jack. dad’s brother, frank, on the other hand, is probably also married to a woman from the patrilineage, so (in fbd marriage) jack and frances betty are probably more closely genetically related.

what the canonical family tree needs, really, are surnames. (why didn’t i think of that sooner?!)

imagine the fbd marriage system above — jack’s new wife, cousin frances betty, doesn’t have to change her last name ’cause she’s in the same patrilineage as jack. jack smith, let’s say, marries his father’s brother’s daughter — uncle frank bob smith’s daughter, cousin frances betty smith. see?

in the mbd marriage system, on the other hand, jack smith marries his mother’s brother’s daughter — uncle mike bill jones’ daughter, cousin mary beth jones. mary beth needs to change her name ’cause she’s from another patrilineage. like confucius say marriage is “the union of two surnames, in friendship and in love.”

previously: genealogical terminology

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mother’s brother’s daughter marriage

so, i found out that mother’s brother’s daughter (matrilateral cross cousin) marriage is, apparently, the most common form of cousin marriage globally.

i looked at father’s brother’s daughter marriage before, and noted one interesting feature in which ego’s paternal uncle (his father’s brother) got to pass his y-chromosome on to his daughter’s male children when she married her paternal cousin (because ego shares his paternal uncle’s y-chromosome). this is something a man wouldn’t normally be able to do (since his daughters don’t inherit his y-chromosome). so, fbd marriage is a really good deal for the paternal uncle.

what happens in mother’s brother’s daughter (mbd) marriage?

well, first of all, the y-chromosome doesn’t really matter here because ego doesn’t share a y-chromosome with any of his maternal relatives (unless everyone’s really inbred!).

in the case of x-chromosomes, ego inherits just one x-chromosome from his mother — an x that is a recombination of her two x-chromosomes. so, let’s track her two x-chromosomes.

in the case of ego’s mom’s maternal x-chromosome (i.e. the one she inherited from her mom), ego’s mother’s brother shares an x-chromosome similar, but not identical, to the one that ego’s mom has. (each of them inherited a recombined x-chromosome from their mother.) he passes an (almost) intact copy on to his daughter (the mbd), while ego gets part of his mom’s maternal x-chromosome recombined. the result looks like this (click on images for LARGER versions):

so there’s a few bonuses for several individuals here:

– some of ego’s x-chromosomal dna passes on to ego’s son via ego’s wife (the mbd) — normally a male doesn’t pass any x-chromosomal dna onto his sons;
– ego’s daughters get an extra amount of his x-chromosomal dna via their mother — another way of looking at it is that the mbd gets to pass on an extra amount of her x-chromosomal dna via ego;
– both ego’s mom and his maternal uncle get extra amounts of their x-chromosomal dna in their female grandchildren, and ego’s mom gets to pass some of her x-chromsomal dna on to her son’s male children, something she normally wouldn’t have been able to do.

ok. so that was one of ego’s mom’s x-chromosomes. what about the other one? the other one she inherited from her father, so she doesn’t share it with her brother. so it looks like this:

not very exiciting.

buuuuuut, what if ego’s dad had also married his mbd? that’s how they do it, ya know.

then it would look like this:

as you can see, ego’s father would also get to contribute some of his x-chromosomal dna to his female grandchildren’s genomes (via ego’s mother), something he wouldn’t have done otherwise.

so, that’s a short summary of what happens with the x- and y-chromosomal dna in mother’s brother’s daughter marriage. let me know if you see anything else of interest — or if you see an error in something i wrote here (i am experiencing a bit of a cupcake-induced brain fog after today’s festivities (~_^) ).

previously: father’s brother’s daughter marriage and coefficients of relationship – cousin marriage – grandparents

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fbd marriage – genetic relatedness amongst nuclear family members

ok. so here’s what father’s brother’s daughter (fbd) marriage looks like:

the first thing to notice is that if you marry your fbd (or your fbs if you’re a chick) is that your children are now also your cousins.

yes. ’cause, if your cousins’ children are your cousins (e.g. your first-cousins’ children are your first-cousins once removed), then if you marry your first-cousin, then your kids are your first-cousins once removed.

ok? ok.

now, my question is: how related are these people, genetically?

a guy and his fbd share 1/8th or 12.5% of their autosomal dna (probability says) — and that’s it. they don’t share a y-chromosome like the guy does with his fbs. just 1/8th of their autosomal dna.

so, now we can work how how related these nuclear family members are.

normally (without any inbreeding) this is what the genetic relatedness looks like:

F–s = 1/2 autosome + y-chromosome
F–d = 1/2 autosome + 1 x-chromsome
M–s/d = 1/2 autosome + 1 x-chromsome

with the inbreeding of two first-cousins, though, we have to add in that 1/8th that is shared between them. and, if i have this right (do i have this right, r.a.? anybody?), the new calculation should look like this:

F–s = 1/2 autosome + 1/16th autosome + y-chromosome
F–d = 1/2 autosome + 1/16th autosome + 1 x-chromosome
M–s/d = 1/2 autosome + 1/16th autosome + 1 x-chromsome

the coefficients of relatedness (rounded to four decimal points) i get then are:

F–s/s–F = 0.5523
F–d = 0.5684
d–F = 0.5593
M–s/d = 0.5593
s–M = 0.5684
d–M = 0.5593

in other words, the people above (probably) share a lot more genes than this nuclear family (below) that is not inbred:

F–s/s–F = 0.4920
F–d = 0.5081
d–F = 0.5000
M–s/d = 0.5000
s–M = 0.5081
d–M = 0.5000

that’s all for now!

key to terms.

previously: father’s brother’s daughter marriage and new and improved coefficients of inbreeding

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genealogical terminology

in case you want to follow my ongoing exploration of kinship relationships from a genetic point-of-view, i thought i’d post a handy guide to all the familial relationships — they can, very quickly, get quite confusing in an i’m-my-own-grandpa sort-of way.

to start:

and here’s what those codes stand for:

F = father
M = mother
s = son
d = daughter
B = brother
Z = sister
FB = father’s brother (paternal uncle)
FZ = father’s sister (paternal aunt)
MB = mother’s brother (maternal uncle)
MZ = mother’s sister (maternal aunt)
FBD = father’s brother’s daughter (patrilateral parallel cousin, female)
FBS = father’s brother’s son (patrilateral parallel cousin, male)
FZD = father’s sister’s daughter (patrilateral cross cousin, female)
FZS = father’s sister’s son (patrilateral cross cousin, male)
MBD = mother’s brother’s daughter (matrilateral cross cousin, female)
MBS = mother’s brother’s son (matrilateral cross cousin, male)
MZD = mother’s sister’s daughter (matrilateral parallel cousin, female)
MZS = mother’s sister’s son (matrilateral parallel cousin, male)

here’s all about parallel and cross cousins.

and the grandparents:

PGF = paternal grandfather (father’s father)
PGM = paternal grandmother (father’s mother)
MGF = maternal grandfather (mother’s father)
MGM = maternal grandmother (mother’s mother)

also, from the point-of-view of a grandparent, one could refer to the grandchildren as PGS or PGD, for example, depending on the relationship.


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father’s brother’s daughter marriage

or fbd marriage (or patrilateral parallel cousin marriage). i mentioned this before (and i’m sure i’ll mention it again).

cousin marriage is pretty common in the world. but most peoples prefer to marry their cross cousins, i.e. (from the point-of-view of a son) father’s sister’s daughter or mother’s brother’s daughter.

however, a few groups of peoples preferentially follow the fbd system. korotayev (2000) convincingly showed that those peoples are mostly to be found in those areas of the world that were a part of the eighth century islamic caliphate. or, here:

he said (in that same article):

“Islamic law does not prohibit FBD marriage, nor does it impose (or even recommend) it (Schacht 1964; al-Jazi:ri: 1990:60-61). But most traditional cultures have a clear perception that marriage between a man and his FBD is incestuous. This is evident in the fact that in most languages a kinship term for FBD (or MSD) would be identical with a kinship term for one’s sister. This normally implies that marriage with a FBD (or MSD) would be perceived as equivalent to marriage with a sister (Korotayev 1999). There appears to be something here that Kronenfeld (pers. comm.) called a ‘cognitive problem’….”

i think fbd marriage is considered incestuous by most peoples because it creates strongly endogamous lineages. look here — here’s fbd marriage versus fzd (father’s sister’s daughter) marriage. look what happens: in fbd marriage, the men and the women all stay within the same clan. that’s hyper-endogamy if you ask me. in fzd marriage, in contrast, the women move between clans. (the straight lines are men, the dotted lines are women, and the big dots are, well, the union of a man and woman.)

continuing with korotayev, where on earth did fbd marriage come from?:

“At the time of its origin, FBD marriage had nothing to do with Islam. The cognitive problem solution seems to have occurred somewhere in the Syro-Palestine region well before the birth of Christ. Rodionov (1999) has recently drawn attention to the fact that this marriage pattern is widespread in the non-Islamic cultures of this area (e.g., Maronites or Druze) and that it has considerable functional value in this non-Islamic context in facilitating the division of property among brothers after their father’s death (Rodionov 1999). Like Rodionov (1999), I believe that this marriage pattern could hardly be attributed to Islamic or Arab influence here. It seems, rather, that this marriage pattern in the Islamic world and the non-Islamic Syro-Palestinian cultures stems from the same source.

“But prior to the time of Islam, the diffusion of the FBD marriage pattern was rather limited. The only adjacent area where it diffused widely was the Arabian Peninsula (Negrja 1981; Kudelin 1994), where its diffusion can be linked with a considerable Jewish influence in the area well before Islam (Crone 1987; Korotayev 1996; Korotayev, Klimenko, and Proussakov 1999). In any case, by the seventh century, preferential parallel-cousin marriage became quite common among several important Arab tribes (Negrja 1981; Kudelin 1994). In the seventh and eighth centuries, an explosive diffusion of this pattern took place when Arab tribes, backed by Islam, spread throughout the whole of the Omayyid Khalifate. Although preferential parallel-cousin marriage diffused (together with Islam and Arabs) later beyond the borders of the Omayyid Khalifate, the extent of this diffusion was very limited. Hence, the present distribution of FBD marriage was essentially created by the Muslim Arab conquests of the seventh and eighth centuries….”

interesting, huh?

i mentioned over here that i thought the practice should really be called father’s brother’s son marriage — not ’cause i’m a raving feminst who wants everything to be considered from the point-of-view of women (you should know me better than that by now!) — but, rather, because it seems to me to be the father-of-the-bride [“C” in chart below] who really wins out here genetically speaking (which is all that matters, right?). the father-of-the-bride gets to “reunite” his y-chromosome (that he shares with his nephew, his brother’s son) with a quarter of his autosomal dna (his daughter carries half of his autosomal dna) in any male grandkids that he has. what other grandfather gets to do that?:

so what?, you say. here’s what, says i (i.e. relatedness matters).

i also think it’s not a coincidence that, in these societies where fbd marriage exists, you also get these extremely paternalistic societies where women are shrouded in burkas or aren’t allowed to drive or whatever. also, the whole honor killing thing. like rs said here, the males in such societies become “super homies” with each other. exactly! why? ’cause they are really closely related genetically.

i suspect that both the degree and type of genetic relatedness in a society affect all sorts of behaviors of its members (especially those related to reproduction) as well as societal norms and even ideologies (again, especially those related to reproduction).

emmanuel todd seems to have gotten close to this idea as well, although i don’t think he got the genetic side of it (i haven’t actually gotten my hands on a copy of this book yet — gosh-d*rnit!). here’s a blurb about his book, “The Explanation of Ideology: Family Structure and Social Systems (Family, Sexuality and Social Relations in Past Times)”:

“Some parts of the world are dominated by communism, others by Catholicism or by Islam and yet others by liberal doctrines. Why should this be? And why has communism triumphed in Russia, China and Cuba, yet failed in Poland, Cambodia and Indonesia? No one knows. Certainly no clear answer lies in variation of climate, environment, race or, even, economic development. The argument of this book is that world variations in social ideology and belief are conditioned by family structure. The author analyzes the distribution of family forms throughout the world, and examines the relations between particular structures, and (for example) communism, totalitarianism and individualism, as well as the links between these forms and a variety of social phenomena – illegitimacy, suicide, infanticide, marital stability and inheritance laws. He offers evidence to support the belief that family structures and kinship patterns lie behind the ideologies that have shaped the history of the 20th century.”

yes, kinship patterns. and what do kinship patterns reflect? mating patterns.

here’s a little hint at what todd had to say about kinship patterns in the once-part-of-the-caliphate muslim world from a helpful reviewer:

“Endogamous Community Family:
a. Spouse selection: Custom, frequent marriage between the children of brothers.
b. Inheritance: Egalitarian – equality between brothers.
c. Family Home: cohabitation of married sons with their parents.
d. Representative Nations, Peoples, Regions: Arab world, Turkey, Iran, Afghanistan, Pakistan, Azerbaijan, Turkmenistan, Uzbekistan, Tadzhikistan.
e. Representative Ideology: Islam.”

it’s not the family structure that matters, it’s the mating patterns i say.

relatedness matters. a LOT, i think.

previously: cousin marriage conundrum addendum and all cousins are not created equal

edit – a nifty diagram of father’s sister’s daughter (fzd) marriage:

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all cousins are not created equal

here’s a chart of standard cousin relationships (charts adapted from here). as you can see, there are four different types of cousins – cross and parallel cousins, both patrilateral and matrilateral:

now it may seem that, apart from being different sexes (triangle=male, circle=female), there’s not much difference between all these cousins, but there is. there are differences in how both the x- and y-chromosomes get passed down in families, and these differences show up in one’s cousins.

first, the y-chromsome — the chromosome that makes men men — passed down virtually unchanged from fathers to sons:

notice that ego shares his y-chromosome with his father (of course) and his brother — AND his father’s brother (i.e. his paternal uncle) AND his father’s brother’s son (i.e. his male paternal cousin). as a group, they are really an inter-generational “band of brothers”, so to speak.

now the x-chromsome.

everybody gets one x-chromsome from their mother, and women get a second x-chromsome from their fathers. the x-chromsome that you get from your mother is a recombined hodge-podge of her two x-chromosomes. the x-chromsome that a woman gets from her father is, like the y-chromosome he passes on to his sons, virtually unchanged.

so, here’s the x-chromosome inherited in the father’s line:

notice that all of a man’s daughters inherit his x-chromosome virutally unchanged.

also, the father’s brother and sister (ego’s paternal uncle and aunt) have inherited an x-chromosome similar to the one that ego’s father has. they are not, however, exactly the same. the three of them have inherited one recombined x-chromosome each from their mother (ego’s paternal grandmother — not indicated on chart). so, while they share some genetic material with each other on their x-chromosomes, the chromosomes are not identical. (ego’s aunt has also inherited one virtually unchanged x-chromosome from her father, ego’s paternal grandfather, not indicated on chart.)

any daughters of the father’s brother will inherit a virtually exact copy of his x-chromosome. so, those cousins’ x-chromosomes (the one they inherit from their father) will be just as similar to their uncle’s (ego’s father) as his brother’s is. (confused yet?!) for instance, if the father and his brother share 50% of the genes on their x-chromosomes, then the father’s brother’s daughters will also share (nearly) 50% of their genes on their x-chromosomes with their uncle (ego’s father). (got it?)

following from that point, ego’s female patrilateral parallel cousins and his sisters will share nearly the same amount of genetic material on their x-chromosomes as the cousins do with their uncle, since ego’s sisters inherit a virtually exact copy of ego’s father’s x-chromosome. (say THAT five times fast!)

ego’s patrilateral cross cousins — the children of ego’s father’s sister — inherit one recombined hodge-podge of their mother’s x-chromosomes each. so, while they do share some genetic material on those x-chromosomes with ego’s father and ego’s sister, it is not such a close relationship as any patrilateral female parallel cousins. it is closer, though, than with any patrilateral male parallel cousins. neither of ego’s patrilateral cross cousins share any genetic material with ego’s x-chromosome, which he inherited from his mother (cue next chart).

so, ego’s mother and her brother and sister (like ego’s father and his brother and sister) share similar genetic material on their x-chromosomes; but, since their x-chromosomes are recombined versions of their mother’s (ego’s maternal grandmother – not indicated on chart) x-chromosomes, their x-chromosomes are not identical to one another.

ego and his brother and sister have each inherited one recombined x-chromosome from their mother. those x-chromosomes are similar, but not identical.

ego’s mother’s sister’s children have each inherited one recombined x-chromosome from their mother. they share some genetic material on those x-chromosomes with ego, but not as much as any of his female matrilateral cross-cousins do. those female cousins inherited an almost exact copy of their father’s x-chromosome (ego’s maternal uncle). they, therefore, probably share a greater amount of genetic material on those x-chromosomes with ego. ego and his male matrilateral cross-cousins do not share any genetic material on their x-chromosomes since those cousins do not inherit an x-chromosome from their father.

whew! got all that?!

i only bring all this up because it has bearing on what i was babbling about in “cousin marriage conundrum addendum“, i.e. that the type of cousin marriage (inbreeding) also matters, not just the coefficient of inbreeding (or kinship or whatever), when we’re discussing the innate social apptitudes of man.”

i also wanted to write all this out to help myself get a grasp of all these relationships. (it ain’t easy!) let me know if you see any errors.

one of these days i’ll terrorize ya’ll with another post(s) showing what happens when all these different sorts of cousins mate. (don’t say i didn’t warn ya!)

see also: Probing Question: Do sisters share a closer genetic proximity than other siblings? and Grandma plays favourites: X-chromosome relatedness and sex-specific childhood mortality

previously: cousin marriage conundrum addendum

update 03/10: i tweaked some of the wording in this post to try and make it a bit clearer. (don’t know if i succeeded or not!) none of the changes were substantial.

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cousin marriage conundrum addendum

several years ago now, stanley kurtz, steve sailer and parapundit wrote a great bunch of articles/posts about the futility of america trying to secure the oil resources in bring democracy to iraq since the society there is tribal and the tribalism is based on the long-standing iraqi practice of inbreeding (i.e. marrying their cousins).

steve sailer wrote about how cousin marriage leads to “strong nepotistic urges” ’cause, of course, working from the “selfish gene” perspective and bill hamilton’s idea of inclusive fitness, it makes sense to favor your relatives that share a heck of a lot of ur genes over some strangers in the next town.

and the MORE you are related to your relatives (for instance, ’cause ur clan members have been inbreeding for generations), you’d think the MORE you’d favor them. which is exactly what we see in the world.

from cousin marriage conundrum:

“In Iraq, as in much of the region, nearly half of all married couples are first or second cousins to each other. A 1986 study of 4,500 married hospital patients and staff in Baghdad found that 46% were wed to a first or second cousin, while a smaller 1989 survey found 53% were ‘consanguineously’ married. The most prominent example of an Iraqi first cousin marriage is that of Saddam Hussein and his first wife Sajida.

By fostering intense family loyalties and strong nepotistic urges, inbreeding makes the development of civil society more difficult. Many Americans have heard by now that Iraq is composed of three ethnic groups — the Kurds of the north, the Sunnis of the center, and the Shi’ites of the south. Clearly, these ethnic rivalries would complicate the task of ruling reforming Iraq. But that’s just a top-down summary of Iraq’s ethnic make-up. Each of those three ethnic groups is divisible into smaller and smaller tribes, clans, and inbred extended families — each with their own alliances, rivals, and feuds. And the engine at the bottom of these bedeviling social divisions is the oft-ignored institution of cousin marriage.

“The fractiousness and tribalism of Middle Eastern countries have frequently been remarked. In 1931, King Feisal of Iraq described his subjects as ‘devoid of any patriotic idea, connected by no common tie, giving ear to evil; prone to anarchy, and perpetually ready to rise against any government whatever.’ The clannishness, corruption, and coups frequently observed in countries such as Iraq appears to be in tied to the high rates of inbreeding.

“Muslim countries are usually known for warm, devoted extended family relationships, but also for weak patriotism. In the U.S., where individualism is so strong, many assume that ‘family values’ and civic virtues such as sacrificing for the good of society always go together. But, in Islamic countries, loyalty to extended (as opposed to nuclear) families is often at war with loyalty to nation. Civic virtues, military effectiveness, and economic performance all suffer.

“Commentator Randall Parker wrote, ‘Consanguinity [cousin marriage] is the biggest underappreciated factor in Western analyses of Middle Eastern politics. Most Western political theorists seem blind to the importance of pre-ideological kinship-based political bonds in large part because those bonds are not derived from abstract Western ideological models of how societies and political systems should be organized. Extended families that are incredibly tightly bound are really the enemy of civil society because the alliances of family override any consideration of fairness to people in the larger society. Yet, this obvious fact is missing from 99% of the discussions about what is wrong with the Middle East. How can we transform Iraq into a modern liberal democracy if every government worker sees a government job as a route to helping out his clan at the expense of other clans?'”

[btw – i highly recommend reading steve’s “cousin marriage conundrum” and all of parapundit’s posts on the topic.]

this is why i was babbling about the levels of cousin marriage in egypt (38.9% in 2000) the other day. egyptians are inbred like the iraqis — so there’s a lot of nepotism and corruption and generally not getting along with other, not-so-related egyptians. egypt has probably functioned as well as it has over the last few decades precisely because they haven’t had a free democracy and, as meng b pointed out, the military has basically been running the place (which a majority of egyptians don’t actually mind!).

what stanley kurtz absolutely nailed, tho, is the fact that not only do a lot of middle easterners and south asians inbreed a lot, they also do it in a very special way.

a very common form of marriage in that part of the world — which tends to be avoided by most other human populations, btw — is called “father’s brother’s daughter” (fbd) marriage or patrilateral parallel cousin marriage, which sounds like a bunch of gobbledygook but just means that the typical form of marriage is that of brothers’ children (i.e. cousins who share a common paternal grandfather -or- cousins whose fathers are brothers).

what difference does that make? a LOT. for one thing, it means that pretty much all of the men in an extended family share (virtually) the same y-chromosome. the genes that make them men? — they have pretty much the same exact ones.

to my mind, the practice should really be called “father’s brother’s son” marriage because, in terms of the y-chromosome anyway, the advantage in this arrangement goes to the father-of-the-bride since he gets to have (virutally) his y-chromsome inherited by any grandsons his daughter bears since she will be married to his paternal nephew [click on chart for LARGER version – adapted from here]:

somehow, some way — and i haven’t thought it through fully yet — fbd marriage makes the males in an extended, inbred family — like the ones in the middle east/south asia — very paternalistic.

again, stanley kurtz nailed it in “veil of fears” [read that, too]:

“The ‘family’ to which a Muslim Middle Easterner is loyal, however, is not like our family. It is a ‘patrilineage’ — a group of brothers and other male relatives, descended from a line of men that can ultimately be traced back to the founder of a particular tribe. Traditionally, lineage brothers will live near one another and will share the family’s property. This willingness of a ‘band of brothers’ to pool their labor and wealth is the key to the strength of the lineage.

“But the centrality of men to the Muslim kinship system sets up a problem. The women who marry into a lineage pose a serious threat to the unity of the band of brothers. If a husband’s tie to his wife should become more important than his solidarity with his brothers, the couple might take their share of the property and leave the larger group, thus weakening the strength of the lineage.

“There is a solution to this problem, however — a solution that marks out the kinship system of the Muslim Middle East as unique in the world. In the Middle East, the preferred form of marriage is between a man and his cousin (his father’s brother’s daughter). Cousin marriage solves the problem of lineage solidarity. If, instead of marrying a woman from a strange lineage, a man marries his cousin, then his wife will not be an alien, but a trusted member of his own kin group. Not only will this reduce a man’s likelihood of being pulled away from his brothers by his wife, a woman of the lineage is less likely to be divorced by her husband, and more likely to be protected by her own extended kin in case of a rupture in the marriage. Somewhere around a third of all marriages in the Muslim Middle East are between members of the same lineage, and in some places the figure can reach as high as 80 percent. It is this system of ‘patrilateral parallel cousin marriage’ that ex plains the persistence of veiling, even in the face of modernity.

“By veiling, women are shielded from the possibility of a dishonoring premarital affair. But above all, when Muslim women veil, they are saving themselves for marriage to the men of their own kin group. In an important sense, this need to protect family honor and preserve oneself for an advantageous marriage to a man of the lineage is a key to the rise of Islamic revivalism.”

the particular sort of clannishness that we see in the middle east and parts of south asia that steve sailer talked about in “cousin marriage conundrum” is based on: 1) inbreeding, AND 2) the type of inbreeding.

the societies in that part of the world are split into a myriad of extended families and clans and tribes that will never get along so long as they continue their current marriage practices.

previously: on the origins of the multicultacracy, aígyptos, assimilation interrupted, kissin’ cousins.

update 03/09: see also all cousins are not created equal


double bonus:

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