recognizing your un-kin

if you want to be un-altruistic toward some un-kin of yours, it might be useful if you could spot who they are.

here’s some neat research [pdf] suggesting that perhaps we can do just that (further research is required, of course). this is one of those manipulated photographs studies — you know — where they take photos and alter them to look more or less like the subjects. note that the study was done on w.e.i.r.d. students — and way more females (n=112) than males (n=32):

“Kin recognition: evidence that humans can perceive both positive and negative relatedness” (2012)

“… The evolution of spite would have been greatly facilitated by the ability to recognize negative relatives (West & Gardner, 2010). The current study is the first to find such an ability among humans, one of only a handful of species (Keller & Ross, 1998; Giron & Strand, 2004) for which there is evidence of negative relatedness recognition, by introducing a novel cue to negative relatedness (negative self-resemblance). Specifically, we found opposing effects of positive and negative self-resemblance – cues to positive and negative relatedness, respectively – on trusting and attractiveness attributions, as predicted. This result provides a foothold for the possibility of the evolution of spiteful behaviour among humans. Future research should examine this possibility.

“Although the effects of positive and negative self resemblance in our study were generally small, our study was an experimental one. Thus, we controlled the strength of the manipulation. It was our intention to make the stimuli subtle, to ensure that the participants would not discover the nature of the manipulation. A subtle manipulation, however, will tend to lead to subtle effects. What we hoped to show was not that the positive and negative self-resemblance manipulations had large effects on preferences or behaviour in the context of a laboratory experiment, but that they had predictable effects at all, especially as these effects speak to theory (Prentice & Miller, 1992).

Relative to matched participants, focal participants generally had positive preferences for their own positive self-resembling faces but negative preferences for their own negative self-resembling faces across contexts….

here’s the relevant graphic:

negative relatives

Spite is hypothesized to evolve under relatively restrictive conditions (West & Gardner, 2010), and so it is expected to be rare. However, two conditions may, together, favour its evolution: (1) ‘viscous’ breeding systems and (2) the ability to recognize negative relatives. Population viscosity can make competition increasingly local among individuals (Taylor, 1992a,b), and local competition encourages the evolution of spite (Gardner & West, 2004). Furthermore, individuals immigrating into a viscous population may be strongly negatively related to members of the indigenous population, because immigrants are highly unlikely to bear the same (relevant) alleles as indigenous individuals (Krupp et al., 2011).”

for “viscous breeding systems” i think we can safely insert “inbreeding” or “cousin marriage” or “consanguineous matings.” they are all certainly viscous.

“Negative relatedness recognition can improve the targeting of a spiteful action to increase indirect fitness benefits (by delivering harm specifically to negative relatives whilst sparing positive ones), and our results provide evidence that humans have the mechanisms in place to do precisely this. Moreover, countless animal species use phenotype matching to determine relatedness, and other kin recognition systems exist that might also be employed to discriminate against negative relatives (reviewed in Krupp et al., 2011). Further discoveries that organisms have the capacity to recognize negative relatives will lay a foundation for the study of spiteful behaviour, arguably the last great unexplored problem of social evolution….”
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what i’d like to see is some research done on actual inbred populations. maybe a comparison between a non-inbreeding population and an inbreeding one to see if either of the two groups is better at spotting their kin or un-kin.

for that matter, i wonder if kin in inbred populations actually look more like one another than kin in outbred populations (and, therefore, look more unlike non-kin). you would think they ought to since they share more of the same genes with one another. you’d think that’d affect appearance, too. remember the ghoul brothers from syria (click on picture for LARGER view)?:

ghoul brothers

redzengenoist said about them: “It really is striking how much they look like one another. Far more than I would expect the average family group to have similar appearance…. I’m thinking of selection for markedness of ingroup-ness. I can’t help but wonder if having a distinct ‘look’ helps to facilitate the evolutionary advantages of inbreeding….”

i noted: “and, like the big families i’ve known (from my slightly inbred area of the world), some of them look more like each other than they do to the others. the two (chubby guys, roundish faces) on the right and the guy all the way on the left look similar — those three look like mom? or dad? and the other five look more like each other — like the other parent (whichever one).”

maybe it’s easier to spot kin and non-kin in a “viscous” population. the more viscous the better, perhaps.

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where do clans come from?

in “Family Structure, Institutions, and Growth: The Origins and Implications of Western Corporations,” stanford economist avner greif wrote [pgs. 308-09]:

“There is a vast amount of literature that considers the importance of the family as an institution. Little attention, however, has been given to the impact of the family structure and its dynamics on institutions. This limits our ability to understand distinct institutional developments — and hence growth — in the past and present. This paper supports this argument by highlighting the importance of the European family structure in one of the most fundamental institutional changes in history and reflects on its growth-related implications.

“What constituted this change was the emergence of the economic and political corporations in late medieval Europe. Corporations are defined as consistent with their historical meaning: intentionally created, voluntary, interest-based, and self-governed permanent associations. Guilds, fraternities, universities, communes, and city-states are some of the corporations that have historically dominated Europe; businesses and professional associations, business corporations, universities, consumer groups, counties, republics, and democracies are examples of corporations in modern societies….

“In tracing the origins of the European corporations, we focus on their complementarity with the nuclear family. We present the reasons for the decline of kinship groups in medieval Europe and why the resulting nuclear family structure, along with other factors, led to corporations. European economic growth in the late medieval period was based on an unprecedented institutional complex of corporations and nuclear families, which, interestingly, still characterizes the West. More generally, European history suggests that this complex was conducive to long-term growth, although we know little about why this was the case or why it is difficult to transplant this complex to other societies….

“The conquest of the Western Roman Empire by Germanic tribes during the medieval period probably strengthened the importance of kinship groups in Europe. Yet the actions of the church caused the nuclear family — consisting of a husband and wife, children, and sometimes a handful of close relatives — to dominate Europe by the late medieval period.

The medieval church instituted marriage laws and practices that undermined kinship groups…. The church … restricted marriages among individuals of the same blood (consanguineous marriages), which had historically provided one means of creating and maintaining kinship groups….

“European family structures did not evolve monotonically toward the nuclear family, nor was their evolution geographically or socially uniform (Greif, 2006, chap. 8).** By the late medieval period, however, the nuclear family was dominant. Even among the Germanic tribes, by the eighth century the term ‘family’ denoted one’s immediate family and, shortly afterwards, tribes were no longer institutionally relevant. Thirteenth-century English court rolls reflect that even cousins were as likely to be in the presence of nonkin as with each other. The practices the church advocated (e.g., monogamy) are still the norm in Europe. Consanguineous marriages in contemporary Europe account for less than 1 percent of the total number of marriages, in contrast to Muslim and Middle Eastern countries where such marriages account for between 20 and 50 percent per country (Alan H. Bittles, 1994). Among the anthropologically defined 356 contemporary societies of Euro-Asia and Africa, there is a large and significant negative correlation between the spread of Christianity (for at least 500 years) and the absence of clans and lineages; the level of commercialization, class stratification, and state formation are insignificantly correlated (Andrey V. Korotayev, 2003).”
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the presence (or absence) of clans in societies is somehow connected to the mating patterns of societies. in fact, it seems to be that a whole range of kinship-based societal types is somehow connected to a whole range of mating patterns: the “closer” the mating patterns in a society, the more “clannish” it tends to be — the more distant the mating patterns, the less “clannish.”

so we see a spectrum of “clannish” societies ranging from the very individualistic western societies characterized by nuclear families and, crucially, very little inbreeding (cousin marriage, for instance) to very tribal arab or bedouin societies characterized by nested networks of extended families and clans and large tribal organizations and having very high levels of inbreeding (specifically a form of very close cousin marriage which increases the degree of inbreeding). falling somewhere in between these two extremes are groups like the chinese whose society is built mostly around the extended familiy but in some regions of china also clans — or the medieval scots (especially the highland scots) whose society for centuries was built around the clan (h*ck, they even coined the term!). these “in-betweener” groups are, or were, characterized by mid-levels of inbreeding (typically avoiding the very close cousin marriage form of the arabs).

furthermore, not only do the degrees of extended family-ness/clannish-ness/tribal-ness in societies seem to be connected to the degrees of inbreeding in those societies, the degrees of “clannism” also seem to be connected to the degree of inbreeding — the more inbreeding, the less civicness, the less democracy, the more corruption, and so on.

it’s not clear what exactly the mechanism(s) behind this inbreeding-leads-to-clannishness pattern is, but since mating patterns are involved, and mating is a very biological process, it seems likely (to me anyway) that the explanation is something biological — i.e. some sort or sorts of evolutionary process/es — like natural selection — resulting in different/different degrees of behavioral traits related to “clannism” in different populations with inbreeding acting as a sort of accelerant for those processes.

clans and clannism, then, are not things that peoples “fall back on” in the absence of a state as mark weiner suggests in The Rule of the Clan [kindle locations 106-108]:

“[I]n the absence of the state, or when states are weak, the individual becomes engulfed within the collective groups on which people must rely to advance their goals and vindicate their interests. Without the authority of the state, a host of discrete communal associations rush to fill the vacuum of power. And for most of human history, the primary such group has been the extended family, the clan.”

rather, people’s attachments to their extended families/clans/tribes — and, more importantly, their tendencies towards clannish behaviors — are likely innate behaviors. and those behaviors likely vary, on average, between populations since (long-term) mating patterns have varied — and, indeed, still vary — between populations.

such innate behaviors cannot be changed overnight — certainly not within a generation or even two (evolution does take some amount of time — but not, necessarily, extremely long amounts of time either) — and definitely not by simply changing a few laws here and there in the hopes of encouraging individualism. as avner greif grasped, although probably not fully because he’s likely missed the underlying biology of what he’s noticed, family structures need to be altered in order to effect changes to larger societal structures (again, all via tweaks to innate behavioral tendencies). and, again, that can’t be done overnight — as greif pointed out, the process in europe began in the early medieval period (with the church’s bans on cousin marriages) and didn’t really start to take hold until the late medieval period — i.e. a 500 year (or, conservatively, a ca. 25 generation) timeline.
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see also: Cousin Marriage Conundrum by steve sailer and Why Europe? by michael mitterauer (in particular chapter 3) and Institutions and the Path to the Modern Economy: Lessons from Medieval Trade by avner greif.

**see “mating patterns in europe series” in left-hand column below ↓ for further details.

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inbreeding and outbreeding

i keep saying that i’ll define more clearly what i mean by “inbreeding” and “outbreeding,” but i never do. finally! — here i am, and i’m gonna do it! (^_^)

from the oxford dictionary of biology:

inbreeding: “Mating between closely related individuals, the extreme condition being self-fertilization, which occurs in many plants and some primitive animals.” (see also wikipedia.)

outbreeding: “Mating between unrelated or distantly related individuals of a species.”

great. but what’s “closely related” or “unrelated” or “distantly related”? self-fertilization doesn’t really apply to humans (at least not very often — i hope), so where to draw the line between “closely related” and “distantly related”?

i’m primarily interested in the evolution of altruism and other “innate social aptitudes” in man [pdf] — and here’s where inclusive fitness comes into the picture, btw — and the role that inbreeding and outbreeding might play in all that.

inbreeding in and of itself does not change the frequencies of genes in a population — it just moves them around, concentrating them in certain lineages. however, wade and breden showed in some mathematical wizardry modelling that, under certain circumstances, long-term, sustained inbreeding can, in fact, lead to increased frequencies of “genes for altruism” in a population.

wade and breden looked at four inbreeding scenarios: 1) self-fertilization (doesn’t happen in humans); 2) if the mating individuals shared half (50%) their genomes in common (like parent-offspring matings or sibling matings); 3) if the mating individuals shared 20% of their genes in common (this is somewhere in between first cousins and double-first cousins or uncle-niece/aunt-nephew); and 4) if the mating individuals shared no genes in common (not the typical pattern in human matings). most human populations do not practice parent-offspring/sibling matings — in fact, it’s usually avoided and considered by most as really icky. but quite a lot of peoples regularly marry first cousins, and some (in the arab world/middle east) even often marry double-first cousins — nor is the world short on uncle-niece pairings (southern india, for example — or hasidic jews).

wade and breden found that, under certain circumstances, long-term, sustained matings between individuals that share 20% of their genomes in common can lead in an increase in altruism genes in that population. first cousin marriage, probably the most common form of inbreeding in humans, is a little short of what wade and breden looked at, but it’s not terribly far away either (12.5% relatedness vs. 20% relatedness). you would think that the slope of the line for inbreeding at 12.5% relatedness would fall somewhere in between that for 0% and 20% (solid black line) on wade and breden’s lower graph here:

wade and breden 02 small

in clinical genetics, most researchers look at degrees of inbreeding that are between second cousins or closer, commonly referred to in the literature as consanguineous marriages. since i get a lot of my data on inbreeding from such studies, it’s kinda handy for me to define inbreeding as anything between second cousins or closer, but in reconsidering wade and breden’s results, i’m thinking that maybe i should only concentrate on first cousins or closer. for now i think i’ll stick to second cousins or closer, but i reserve the right to change my mind (it is a woman’s prerogative, isn’t it? still?).

so, on this blog:

– inbreeding = in a population, a general pattern of regular and sustained mating between individuals who are related to one another as second cousins or closer.

– outbreeding = in a population, a general pattern of regular and sustained mating in which individuals avoid second cousins or closer.

notice the “regular and sustained” bit. that’s important. we’re not talking here about occasional marriages between cousins. it has to be a regular practice in a society. i’m not sure what the frequency of the inbreeding needs to be. it will vary according to population size, of course — the smaller the population, the more closely related everyone’s going to be anyway (e.g. the yanomamo). in a larger population? — dunno. definitely when 50% of marriages are consanguineous over the long-term i think the frequencies of “genes for altruism” are going to increase pretty rapidly (i’ll come back to what sorts of altruism in another post). 30%? probably. 3%? not really.

outbreeding, too, needs to be “regular and sustained” to have any effect, i.e. to have a population slide back down wade and breden’s slope in reverse. one generation of outbreeding probably won’t have much of an effect, i think. evolution (natural selection) does take some time, after all. also, if one inbreeding group interbreeds with another inbreeding group, that’s NOT outbreeding according to my definiton. technically it is in biological circles, but if we’re talking about two populations that have been inbreeding for a long time and, therefore, have acquired a lot of genes for my “familial altruism,” then all they’re doing by interbreeding is swapping familial altruism genes. for example, if you’re the early medieval irish and are clannish because you’ve been inbreeding for who-knows-how-long, the “outbreeding” that you do with the vikings when they show up (probably) doesn’t count wrt altruism, because they’re a long-term inbreeding group, too.

to have any effect on the frequency of certain “genes for altruism,” outbreeding — like inbreeding — needs, i think, to be regular and sustained over the long-term, as it was with europeans (mostly northwest europeans) since the early medieval period (see also mating patterns in europe series in left-hand column below ↓ for more details) and, perhaps, some other groups like the semai in malaysia.

previously: inbreeding and the evolution of altruistic behavior

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consanguinity and democracy

steve sailer posted about this paper the other day — from the amazingly awesome michael woodley and his partner in crimethink edward bell:

Consanguinity as a Major Predictor of Levels of Democracy: A Study of 70 Nations

oh, how such a study just warms hbd chick’s cold, little heart! (~_^)

using the good, ol’ consang.net data on cousin marriage rates (which are great but have a lot of problems — i’ll get into that in another post) and data on democracy from polity iv and the eiu democracy index, woodley and bell found pretty strong negative correlations between first-/second-cousin marriage rates in societies and how democratic those societies are: –0.632 between consanguinity and the polity iv data, and –0.771 with the eiu data. (as steve points out, a -0.6 correlation in the social sciences is something to make you stop and go hmmmm, never mind a -0.77 correlation.)

in other words, the more cousin marriage in a society, the less democracy.

woodley and bell also looked at a lot of other neat stuff like economic freedom+consanguinity+democracy and percent muslim+consanguinity+democracy and pathogen index+consanguinity+democracy (i like that one!), but i’ll get to those in another post. (in fact, the rest of this week is probably going to be devoted to the woodley and bell paper here on hbd chick, so if you’re sick to death of hearing about inbreeding and democracy, don’t say you haven’t been warned!)

woodley and bell say:

“Consanguinity … appears to severely restrict the political and social fluidity characteristic of democratic systems, as individual allegiances are primarily to kinship groupings where sophisticated group-level free-rider detection and social identity mechanisms serve to discourage expressions of self-interest that do not maximize collective utility (MacDonald, 2001, 2002). This process of collective utility maximization is consistent with the notion of inclusive fitness in which individuals exhibit altruistic behaviors toward those with whom they share genes, thus indirectly increasing their fitness (Hamilton, 1964; Rushton, 1989, 2005; Trivers, 1971).”

they also say:

“A further shortcoming of the study is its cross-sectional nature; a panel study using data gathered at regular intervals would be ideal for testing the hypotheses and models presented in this study.”

yes. i’ve been thinking that there are at least two things going on with regard to inbreeding and man’s innate social aptitudes (and their expressions like democracy or no democracy):

1) genetic similarity. so, as woodley and bell said, “individuals exhibit altruistic behaviors toward those with whom they share genes.” thus, in highly inbred societies, individuals favor their own extended family members at the expense of their neighbors and unrelated members of their society simply because they are much more genetically related to their [edit] extended family members than individuals in outbred societies are to theirs. this is a very direct effect — change the relatedness, change the behavior patterns. and, so, liberal democracy will simply never work in inbred societies — or not work very well anyway — because you get clannishness.

2) the evolution of “genes for altruism” over the longer term. i think that, in addition to genetic similarity, we’re also looking at populations with different types and/or frequencies of “genes for altruism” due to their long-term mating patterns. i think it could’ve made a difference that northwest europeans have been outbreeding a lot since the early medieval period while arabs having been inbreeding a lot since … well, i’m not sure … probably since at least whenever some jewish tribes from the levant migrated into the arab peninsula. this is a long-term effect — change the relatedness over the long-term, and you might change at least the frequencies of “genes for altruism” in the population. you’d think the selection pressures for different sorts of altruism genes would change, too, if you went from an outbred to inbred society (bushmen vs. yanomamo, for example) or vice versa. in other words, you’d think different altruism genes might be selected for in different types of societies.

this is one of the reasons that i say there are problems with the consang.net data, i.e. that they lack time-depth or, as woodley and bell said, they offer only a cross-sectional look at consanguinity.

for instance, the consang.net data for china averages to a rate of 5% (per woodley and bell), but all of the data for china come from the twentieth century. however, the chinese have been seriously marrying their cousins since at least the third century b.c. and, as far as i know, the rates only slowed down in the twentieth century (and maybe not to the extent one would think from looking at the consang.net data) — and after that, they kept on marrying very locally (endogamously) until very, very recently.

i think woodley and bell would find much higher correlations between consanguinity and democracy if they had long-term consanguinity data. (what will probably need to be used is some sort of genetic data.)
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the woodley and bell paper [pdf].

the classics: Veil of Fears by stanley kurtz; Consanguinity prevents Middle Eastern political development by parapundit; and Cousin Marriage Conundrum by steve sailer.

previously: democracy and endogamous mating practices and the corporate nature of european societies and liberal democracy and “hard-won democracy” and consanguinity + corruption = correlation

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consanguinity + corruption = correlation

the awesome epigone has found a correlation of .44 between the amounts of (mostly) current consanguineous (first-/second-cousin) marriages in various societies as indicated by the data available on consang.net and perceptions of corruption by the people in those societies as found by transparency international (thnx, a.e.!). that’s higher than i would’ve guessed beforehand — i gave a bunch of reasons for that over @m.g.’s place which the epigone included in his post, so i won’t bother repeating them here.

i know that correlation is not causation, but it does “waggle its eyebrows suggestively and gesture furtively while mouthing ‘look over there,” so i’ll bet anyone a nickle — no, a dime! — that there is a connection here (and that connection is altruism/other innate social aptitudes [pg. 329+]).

i think audacious’ correlation would be even larger if there was some time depth to the inbreeding/endogamy data. what i’d like to see is:

– all the genes for altruism (and other innate social aptitudes) in man discovered so we (meaning teh scientists) can see the hbd differences in altruism, etc., in different populations and trace the evolutionary histories of all these genes in different populations. then someone could check for correlations between the gene frequencies and corruption (and other neat behaviors like nepotism).

in lieu of that, what i’d like to see is:

– all, or at least lots, of the people on the planet getting their dna sequenced so we (meaning teh scientists) can work out the degrees of relatedness within different populations so we (meaning teh scientists) could at least guess at the evolutionary histories of all these genes for altruism. then someone could check for correlations between the actual degrees of relatedness in different populations and corruption (and other neat behaviors like nepotism).

in lieu of that, what i’d like to see/do is:

– what the audacious epigone did but just with some time depth added to the inbreeding/endogamy data. plus, also, some consideration given to the fact that some forms of cousin marriage (i.e. fbd marriage) amount to more inbreeding than other forms of cousin marriage (e.g. mbd marriage).

for example, maybe two points could be awarded for each (likely) generation in which consanguineous marriages were common (haven’t considered what the cut off oughta be), and one point for each (likely) generation of endogamous marriage. zero points for marrying out. bonus point for fbd marriage. add ’em all up and then compare/contrast with corruption, et. al.

the problem is figuring out exactly how much inbreeding happened at any given point in the past for a population. i know there are ways to get at it by looking at dna — maybe what should be looked for are any correlations between runs of homozygosity in populations and corruption, etc. that would still be looking at a sort of proxy for the presence/frequencies of different sorts of genes for altruism, but it might be interesting anyway.

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inbreeding and the evolution of altruistic behavior ii

in Understanding Human History, michael hart did a real nice job of explaining how kin selection or inclusive fitness works and how “genes for altruism” could be selected for [pgs. 37-38]:

“For about a century after Darwin proposed his theory of evolution, the origin of altruistic behavior in animals remained a puzzle. It was not until the 1960s, when William D. Hamilton proposed his theory of kin selection, that a satisfactory explanation was given. That theory can perhaps best be explained by an example:

“Suppose a man sees his identical twin drowning in a river, and estimates (correctly) that if he were to jump in and try to save his brother the probability of success would be 80%, while the probability that he would die in the attempt would be 20%. Consider these two alternatives:

“a) Some of the man’s genes strongly dispose him to rescue his brother, and he therefore jumps in and tries to save him (‘altruistic behavior’).

“b) The man does not have genes that dispose him to rescue his brother, and he therefore stays on the shore and lets his brother drown (‘selfish behavior’).

“In case (b), exactly one copy of the man’s genes survives, and may later be replicated. However, in case (a), if the rescue attempt is successful, two copies of the man’s genes survive (one in his own body, one in his brother’s). As this will happen 80% of the time, on average 1.6 (= 0.80 × 2) copies of the man’s genes will survive. In this situation, therefore, genes that dispose a person to altruistic behavior will — on average — have more surviving copies than genes that dispose a person to act selfishly and will be favored by natural selection.

“Now consider a slightly different example. Suppose that the man on shore is a brother — but not a twin — of the person who is drowning. Case (b) will still result in one copy of his genes being preserved. However, since ordinary siblings share only 50% of their genes, if the man on shore succeeds in rescuing his brother then (on average) 1.5 copies of the man’s genes will survive. Since 80% of the attempts will be successful, case (a) will on average result in 1.2 (= 0.80 × 1.5) copies of the altruistic genes surviving. Since 1.2 is greater than 1.0, the altruistic genes will be favored by natural selection in this case too.

“Suppose, however, that the two men were not brothers, but merely first cousins. First cousins, on average, share only one-eighth of their genes. In this case, altruistic behavior results in only 0.9 (= 0.80 × 1.125) copies of the man’s genes surviving, and natural selection will therefore favor the genes for selfish behavior.

“The upshot is that a gene that disposes its bearer to behave altruistically toward a close relative can have a selective advantage over one that disposes its bearer to act completely selfishly. Furthermore, this can occur even though the relative never returns the favor, and even if the survival of the relative does not increase the group’s chances of survival. It is not necessary that either reciprocal altruism or group selection operate for kin selection to result in the spread of genes that dispose their bearer to act altruistically toward close relatives.”
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what’s missing from these examples is, of course, inbreeding. and depth of time.

take michael’s second example up there…

“Suppose that the man on shore is a brother — but not a twin — of the person who is drowning.”

…but let’s add that the parents of these brothers were first-cousins. that makes these two guys: brothers AND second-cousins (i.e. the children of two first-cousins). so they probably share not only 50% of their genes in common as brothers, but also 3.13% of their genes in common as second-cousins. so the “push” to jump in the water to save the brother/cousin must be somewhat stronger in the inbred pair than for the brother to save just a plain ol’ brother.

now let’s take this example of michael’s…

“Suppose, however, that the two men were not brothers, but merely first cousins. First cousins, on average, share only one-eighth of their genes.”

…but let’s make them double first-cousins rather than just first-cousins. what happens then?

well, while first-cousins probably share 1/8th or 12.5% of their genes in common, double first-cousins share … well, double that! … or 1/4 or 25% of their genes in common.

what happens to michael’s calculation then?

“In this case, altruistic behavior results in only 0.9 (= 0.80 × 1.125) copies of the man’s genes surviving, and natural selection will therefore favor the genes for selfish behavior.”

in the case of double first-cousins the calculation becomes 0.80 x 1.25 = 1.0. that’s just breaking even using michael’s example, but what if the odds of saving the cousin from drowing are better than 80%?

or what about the depth of time i mentioned above? what if the family of my double first-cousins has been inbreeding for a very long time. a very, very long time. like for fifty generations or more. then the relatedness between all the family members, including these double first-cousins, will be even closer. natural selection ought, then, to favor such double first-cousins jumping in to save each other.

as wade and breden showed (see also previous post), inbreeding can help to accelerate the rate of the evolution (or frequency in a population) of altruism genes [pg. 846]:

[T]he increase in matings between homozygous parents decreases the genetic variance within families, because these matings produce genotypically homogeneous arrays of offspring.”

repeated inbreeding in a family reduces the diversity (whoa!) of the allele types within that family, and if we’re talking about “genes for altruism” here, then the variety of those must get reduced within inbred families, too. in a population that consists of, say, ten inbreeding families, the one that has super-duper altruism genes that lead all of its family members to help each other out more than the members of the other families will have the advantage (provided selection favors that advantage for whatever reasons). and those super-duper altruism genes will no doubt eventually spread to the other families since, in reality, no family groups inbreed 100% of the time anywhere — there will pretty definitely be gene flow between families. so then you’ll get a whole population of super-duper family altruists (note that these people are NOT altruistic to unrelated individuals).

the human populations on earth today that inbreed most closely (within patrilineages) and often practice double first-cousin marriage — AND have been doing this for prolly at least a couple of thousand years (time depth) — are the arabs (who later spread these mating practices to the maghreb, the mashriq and far off places like iraq and afghanistan and all the other ‘stans) and some peoples in the levant like the druze. i think that, because of their long-standing mating practices, they are the prime human examples of wade and breden’s accelerated evolution of altruism thanks to inbreeding.

previously: inbreeding and the evolution of altruistic behavior and more on inbreeding and the evolution of altruistic behavior

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more on inbreeding and the evolution of altruistic behavior

remember this?:

those are a couple of graphs from wade and breden from when they did some mathematical modelling of the selection for “genes for altruism” under different circumstances (see previous post for more details).

the interesting graph is the bottom one which shows what the frequency of “genes for altruism” in a population would be IF selection was strong and IF the alleles in question were dominant. the gene frequencies are on the y-axis (at 1.0 the genes have reached fixation). the number of generations to get to the various gene frequencies is on the x-axis.

the interesting line on the graph for us is the solid line: those are individuals who are about two-times more related to one another than first-cousins in a randomnly mating population. that’s an exaggeration for most human populations, but it’s the most human-like of all the mating patterns they considered. the others are cloning, sib-mating (ewww!), and total outbreeding. so most human populations would be lower than that solid line, but not flatlining like the total outbreeding example. somewhere in between.

anyway. in my previous post i pointed out that after just 50 generations, there is already an increase in the frequency of “genes for altruism” in the solid line population. however, these models start at zero! in other words, the starting point they’re thinking of is if the populations start off with no “genes for altruism” at all. but that can hardly have ever been the case for any human population since altruistic behaviors are found in almost every living being on the planet!: plants, insects … even slime molds! not to mention our closest cousins, other primates.

so the baseline for the frequency of “genes for altruism” in any human population was probably never zero. who knows where it should be? 30%? 40%? 50%? 80%? i really don’t know. but not zero, anyway.

if we just say it was 50% — just picking an example right out of the hat — then the frequency of “genes for altruism” in the inbreeding solid line population increases much more sharply (i.e. the slope of the line is more slopey) over fifty generations than if we start the population off at zero. (look at the solid line between 0 and 50 generations versus 200 and 250 generations. there’s a much sharper increase in the latter group.)

i’m picking out 50 generation timespans, btw, because — at a very conservative estimate (1 generation=25 years) — arabs have been very closely inbreeding for ca. 56 generations (i.e. since at least mohammed’s days and most likely before).

anyway. that is all. (^_^)

previously: inbreeding and the evolution of altruistic behavior

update 05/30: see also inbreeding and the evolution of altruistic behavior ii

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“civicness” in germany and poland

in a post last year, i showed that eastern europeans score very low on “civicness” — i.e. membership in voluntary organizations — at least according to data from the world values survey, 2005-2008. out of the slavic nations, poland (and moldova) scored above the eastern european average, but still well below anglos:

szopeno suggests that this low civic spirit is related to the after effects of living under totalitarian communist regimes:

“In Poland, most of lawyers, doctors, enterpreneurs were executed by nazis, and the rest was killed/deported by soviets. In USSR for generations all those, who were individualistic were executed, escaped to the west etc…. Most never returned…. You have a generations of living in system, were everyone could be your enemy, when you couldn’t talk freely with strangers, when state was your enemy. This had profound effects on psychology….”

i think the first part there — a nation losing its best and brightest — will definitely have a negative effect on society, possibly for quite a few generations. but i don’t really buy that there would be long-lasting effects on a nation’s psyche (unless there are some sorts of epigenetic effects of living in stressful circumstances 24/7 for decades?). i think there’s something deeper going on wrt “civicness.” i have a hard time believing that it’s just a coincidence that regions as diverse as the arab world and eastern europe and spain and italy — all places with a long history of you-know-what — have low scores on civicness. i think there’s something biological going on.

szopeno also suggested that “civicness” might be different in eastern germany than in western since the population in the east was under a totalitarian regime for so long. so, i’ve taken a closer look at “civicness” in west and east germany and in poland.

what i’ve done is taken an average of the percentages replying “belong” (as opposed to “not mentioned”) for the following questions from the world values survey, 1999:

Please look carefully at the following list of voluntary organisations and activities and say…which, if any, do you belong to?

– Social welfare services for elderly, handicapped or deprived people
– Religious or church organisations
– Education, arts, music or cultural activities
– Labor unions
– Political parties or groups
– Local community action on issues like poverty, employment, housing, racial equality
– Third world development or human rights
– Conservation, environment, animal rights groups
– Professional associations
– Youth work (e.g. scouts, guides, youth clubs etc.)
– Sports or recreation
– Women’s groups
– Peace movement
– Voluntary organisations concerned with health
– Other

i’ve used the ’99 survey because it breaks down the responses by region, whereas the later surveys unfortunately do not. for germany and poland, the data are broken down by the sixteen german länder and the sixteen polish voivodeships. the questions are slightly different from the 2005-2008 wave, but some of them are the same. in my previous post, though, i considered “active” members; the 1999 wave options were basically just member or not member.

note that some of the sample sizes for some of the regions are rather small. i should’ve cleaned those out, but didn’t have (make!) the time right now, so consider this post a rough draft!

i’ve plotted the averages against the longitudes of each region (acquired from wikipedia’s geohack) with the idea that both outbreeding and the presence of medieval manorialism (which helped to break down clans and tribes in europe) have a longer history in western europe than in the east, and due to the spread of these practices from west to east across northern europe, i’d expect to find more “civicness” in western europe than in the east, perhaps moving along some sort of gradient from west to east. indeed, i found a negative correlation of 0.76 (-0.76) between membership in a voluntary organization (“civicness”) and longitude (west to east). here is a nifty chart of that (click on image for LARGER version) — the blue squares indicate german länder, the red squares indicate german länder that used to be a part of east germany, and the pink squares indicate polish voivodeships:

so, at least across germany-poland, there is a general west-to-east decrease in civicness.

however, when i checked for correlations between civicness and longitude within each of the countries, while i found a negative 0.66 (-0.66) correlation in germany, there was only a negative 0.39 (-0.39) correlation in poland. so, uncivicness seems to be present across the board in poland, but runs from west-to-east in germany.

hmmmm. those results — less civicness in east germany and across the board in poland — could back up szopeno’s idea of communism’s lingering effects on civic attitudes. maybe he’s right! otoh, manorialism and outbreeding reached eastern germany and poland comparatively late (late medieval period at the earliest for poland) and poland sits astride the hajnal line, so maybe i’m right! (^_^)

never fear! i’ll be looking more at mating patterns and family types in poland (and eastern europe) — and there are other sources on “civicness” in poland to be looked at — so stay tuned!

btw, that blue dot with the 1% (0.93%) average responding that they were members of some sort of voluntary organization? that’s hamburg. the number of samples was on the low side for hamburg, but if the survey results are at all correct, the only “odd” thing i can think of regarding the city is that it is a rather vibrant one. i suspect it might be the low numbers, though. the highest scorer — pretty much as far to the west as you can get in germany — was saarland with nearly one in ten saying that they belonged to some sort of voluntary organization.

and, oh. i also checked for any correlation between “civicness” and latitude. didn’t find anything in germany (-0.39) — but i got an almost perfect uncorrelation for poland (-0.01)! never saw such an uncorrelation before. cool! (^_^)

previously: civic societies and civic societies ii

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