How Inbred are Europeans?

HBD Chick and I talk about how rates of historic inbreeding have had an important impact on the selective pressures acting on the traits of various peoples living today. We have often used Europe and the Middle East as examples of this, because strong regional variations in historic rates of inbreeding exist in those places. Particular among these variations is the history of Northwestern Europe, which had – unique in the world – a long history of avoiding inbreeding. As such, according to HBD Chick’s hypothesis, the region went down a unique historical trajectory because of it.

But what do we mean when we say that one region is more or less inbred than another? What regions across Europe and the Near East are we talking about? In this post l will show you.

This is a map of our current best guess of the rates of historic inbreeding across Europe and parts of the Near East. This map is a guestimate, and is not derived from direct measurements. However, it visualizes what areas we think are the most and least inbred, based on these regions’ histories and other pieces of evidence we have. The colors roughly correspond to HBD Chick’s 11-point clannishness scale:

if we take 1 as the least clannish and 10 as the most clannish, i would rate various groups as follows (these are today’s judgements — i reserve the right to alter these as i go forward and learn more about all of these populations!): 1 – the english (not all of them — probably not the cornish, for instance), some of the dutch

2 – the scandinavians

3 or 4 – the irish

6-7 – the italians, the greeks, the chinese

7-8 – the albanians

10 – the yanomamo

11 – the arabs

These divisions (with some exceptions which soon I’ll note) shouldn’t be taken to be hard and fast. These are general ideas based on the evidence I have so far seen. It is subject to revision, and will probably continue to be updated as I gather more evidence. Overall, the general pattern appears to be considerably longer history of outbreeding in Northwestern Europe and progressively shorter one as you move outward from there.

As we can see, several countries are significantly divided regionally. Most distinct are the United Kingdom, Spain, Italy, and Germany (while Portugal is shown with a north-south gradient, I’m not sure if one exists there). These divisions have had great significance for the past and present of these countries and the countries they sired.

See:

Though this map is an educated guess, it is based on several important pieces of evidence, which I will now review, starting with one the key pieces.

Razib Khan recently objected to HBD Chick‘s hypothesis based on genetic data reviewed by Peter Ralph and Graham Coop. Ralph and Coop looked at identity by descent (IBD), a measure of how many common ancestors individuals within a population share. In short, the more IBD, the more genetically similar the population is. This similarity could signal several things, including a recent population bottleneck or historically small population size (both of which would tend to minimize genetic diversity within the population), or few admixture events in the population’s history. However, it could (and almost certainly does) signal the degree of inbreeding in the population’s mating history.

Ralph and Coop also discussed these data in an earlier presentation. Therein, they produced this map:

The average IBD rates for each of the countries sampled is shown. The lines on the map were drawn by me. They divide the areas of historic outbreeding from the areas that have long-term inbreeders (based on data supplied by HBD Chick, which will be reviewed shortly), which is roughly coterminous with the Hajnal line.

As we can see, my map is in very good agreement with Ralph’s and Coop’s data, particularly the pronounced divide between Western and Eastern Europe, as well as the regional variation across the British Isles. However, one incongruity appears to be Italy, and to a lesser extent, Spain and Greece. At least with the former two, a key problem is that we don’t know what the regional breakdown would look like, and as my map makes clear, there should be a sharp regional divergence in historic inbreeding rates across these countries. As for Greece, and perhaps Turkey, these countries have both seen many admixture events and population movements, which is perhaps responsible for the smaller IBD rates seen there.

Secondly, there’s this map of the perceived corruption across Europe (from Transparency International’s 2012 Corruption Perceptions Index), which produces a striking pattern:

And now, here are a collection of posts detailing data on mating patterns from these various countries (from HBD Chick except where otherwise noted). A similar version of this list can be seen on HBD Chick’s website, however, I wanted to recite them here to have them all in one place for this post:

First, HBD Chick’s european consanguinity bibliography

and western european societal values

England:

but what about the english?

english individualism ii

anglo-saxon mating patterns

consanguinity in england – north vs. south

more on consanguinity in england (and scotland)

exogamous marriage in medieval england

more on medieval england and france

kinship in anglo-saxon society

kinship in anglo-saxon society ii

cousin marriage in 13th-15th century england

Scotland:

mating patterns in medieval/early modern scotland

Ireland:

inbreeding in europe’s periphery

meanwhile, in ireland…

early and late medieval irish mating practices

clannish medieval ireland

early modern and modern clannish ireland

mating patterns, family types, and clannishness in twentieth century ireland

runs of homozygosity in the irish population

France:

what about the franks?

meanwhile, in france…

civicness in france by region

la lignée

Germany:

early medieval germans … again!

more on inbreeding in germanic tribes

more on mating patterns from deutschland (and switzerland)

feuds, tournaments, and reproductive success in medieval germany (franconia)

Spain:

la endogamia en la españa medieval

civicness in spain by region

Italy:

inbreeding in italy

exogamous marriage in northern medieval italy

Those Who Can See: Chalk and cheese

Greece:

ελλάδα

more on greece

Russia and Eastern Europe:

mating patterns in medieval eastern europe

medieval russian mating patterns

traditional family systems in medieval russia

the zadruga

russians, eastern europeans, runs of homozygosity (roh), and inbreeding

mating patterns in baltic populations

The Balkans:

balkan endogamy

more on albanians

The Low Countries:

trees and frisians



Scandinavia:

inbreeding in sweden

inbreeding in 18th and 19th century sweden

the law of jante

(on Iceland) random notes: 09/06/13

EDIT, 12/14/14: mating patterns in medieval norway

There are several historical correlates with this pattern. The earliest was the spread of manorialism:

This spread follows the Hajnal line and roughly tracks areas where there were low rates of inbreeding. Indeed, HBD Chick hypothesized that the manor system contributed to the breakdown of the clans and made cousin marriage considerably more difficult.

This pattern also follows the spread of Christianity, as seen on this map featured over at Dusk in Autumn:



As may be obvious from my map of inbreeding in Europe at the beginning of the post, it appears (we believe) that outbreeding originated in the area around Northeastern France/the Low Countries and Southern England and spread outward from there in all directions. And indeed, perhaps this was the case.

As HBD Chick discusses, the disappearance of references to Germanic kindreds (the Germanic version of the clan, see medieval germanic kindreds … and the ditmarsians | hbd* chick and more on medieval germanic kindreds | hbd* chick) also follows this pattern:

(In that post – ibd rates and kindreds in germanic populations – HBD Chick also examines the samples used in Ralph’s and Coop’s analysis. Some, unfortunately, were woefully small.)

The decline in violence across Europe during the past millennium, which was discussed by Steven Pinker in his book The Better Angels of Our Nature, (discussed here: “violence around the world” | hbd* chick)…

…also follows this pattern…

…as seen from this map drawn by HBD Chick (see historic european homicide rates … and the hajnal line).

As well, supporting the notion that some European countries possess distinct regional variation within them in how inbred their populations are, we have these pieces:

For Britain (from traditional family systems in medieval britain and ireland | hbd* chick):

Germany (and Poland):

Italy (take your pick):

And Spain (from here and here, respectively):

Reinforcing the pattern we see across Europe and much of the world are the results of the World’s Values Survey:

The Northwestern European countries are in a group by themselves. Indeed, this plot excellently follows the east-west divide that exists in Europe, and does an excellent job of catching the north-south divide as well. As per HBD Chick’s hypothesis, the Islamic countries – which are the most inbred of them all – cluster on an opposite pole to the Northwestern European ones.

This correlates to the rates of civic involvement seen across these countries, also discussed by HBD Chick (here and here):

EDIT: Also, HBD Chick has recently posted a table of ranking nations of their individualistic vs. collectivist tendencies, from Geert Hofstede’s Dimensions. Here, the pattern in the same, Northwest European countries rank highly (with Anglos ranking highest), with more inbred countries, particularly Latin American and Muslim countries ranking lowest (see national individualism-collectivism scores).

Further reinforcing our estimation of historic levels of inbreeding across various parts of Europe and the Middle East, as seen on my map, is the fact that many of these countries (the Islamic world) are still actively inbreeding (from consang.net):

Europeans – and for that matter East Asians – have, by in large, ceased inbreeding in the 20th century by the latest. However, first cousin marriage – particularly the highly incestuous father’s brother’s daughter type – is still the rule in the Muslim world, which means that they should be far more inbred than even the most inbred Europeans could hope to be. This gives rise to, according to HBD Chick’s hypothesis, the many fairly unique pathologies found in the Muslim world (also here, Those Who Can See: Arabs and Liberal Democracy: A Primer).

To briefly mention, the problems found in East Asia – particularly China – may be also related to their historically high rates of cousin marriage. See (from HBD chick) abridged history of cousin marriage in china, crash course in chinese clans, and the problem with china. Korea and especially Japan may experience fewer of these problems because they may be further along the “outbreeding” process, as I’ll soon discuss.

(As well, many might note that HBD Chick’s analysis generally doesn’t focus on sub-Saharan Africa much. The current idea is that a type of de facto inbreeding existed there thanks to sub-Saharan Africa’s high rates of polygyny: see monogamy, serial monogamy, and polygamy | hbd* chick. This leads to a form of tribalism that is perhaps significantly less structured than forms elsewhere – perhaps in part due to historically low rates of paternal investment and high male-on-male competition for mates. Also, as HBD Chick noted, the fairly high levels of civicness found in Blacks may be titled towards exclusive, self/in-group interested forms rather than the truly exclusive, out-group oriented ones seen in NW Euros – see: good civicness vs. bad civicness | hbd* chick )

It’s hard to escape the observation that there might be a “sweet spot” when it comes to clannishness (and hence perhaps inbreeding). This is apparently centered somewhere around level “3”. At that level, you get most of the advantages of outbreeding, including liberal democracy, functional institutions, and a high-trust society, but retain a certain level of nationalism and ethnic cohesion that allows the society to resist opening itself to non-reciprocating outsiders, as the most outbred Northwestern Europeans apparently have. Some of these countries in the 3-4 range seem to lack much of the deleterious universalist sentiments found in those scoring 1-2. This may be the case in Finland & Japan, and might explain the interesting “in-between” characteristics these societies have.

And on that point, here are a few more maps that demonstrate the somewhat detrimental universalism of outbred Northwest Europeans:

A general pattern emerges where the least inbred European countries accept the most foreigners, particularly non-European ones (especially Muslims). (The high immigrant populations in the ex-Soviet states are mostly Russians; those in Ireland are primarily from Britain. Spain is on the fence because most of its immigrants are from its former colonies in Latin America.)

Now indeed, to place HBD-Chick’s hypothesis on the most solid footing, we should ideally examine the genetic data to get firmer estimates of the level of long-term inbreeding in these populations, rather than relying primarily on historical data and the traits of modern peoples. This is an undertaking we might pursue in the manner Razib Khan suggested, and this might be a project we will soon address. However, the genetic data we have analyzed so far does support HBD Chick’s hypothesis.

Also, it’s worth noting that historic rates of inbreeding are just one selective force among many (not the least of which being the effects of manorialism, of strong states, and of internal population replacement ala Gregory Clark/Ron Unz) which act on a population (which may act synergistically to produce the traits we see), and close analysis may not reveal a perfect association between modern clannishness and historical rates of inbreeding, perhaps due to the vagaries of other selective forces that have been acting on these populations. I’d be remiss to not mention the effect of geography, climate, and topography on this (from Wikipedia):

Mountains may contribute to inbreeding by making both farming and long-range travel difficult (favoring a pastoral way of life) – see the flatlanders vs. the mountain people | hbd* chick. That is not to say that mountain-dwelling always results in inbreeding; as we saw, the denizens of the Alps managed to avoid it. But it is one factor among many in shaping the selective forces acting upon a people. HBD Chick and I will continue to work, with the hope of getting to bottom of what is going on, as all science aims to accomplish.

For more, please see:

HBD Fundamentals: On the evolution of modern advanced civilized peoples

Also see this brand new post at Staffan’s Personality Blog: The Clannish World of Organized Crime

Edit 3/13/14: See also big summary post on the hajnal line | hbd* chick