linkfest: 05/27/14

Quick Questions for Peter and Rosemary Grant“There is widespread misunderstanding about evolution; that it occurs extremely slowly and therefore cannot be studied in a person’s lifetime. This was the view of Charles Darwin. Many biologists and others now know that this is not correct…. The idea that animals as large as birds might evolve before our eyes is not so well known, yet our study in the entirely natural world of Daphne Major island has revealed this does in fact happen when there is a change in the environment, and it takes place over a period as short as a year, and repeatedly.” – h/t billare!

Is DNA Multilingual?“The genetic code has traditionally been viewed as a universal set of instructions, exquisitely tuned to maintain robust stability and allow evolution-sustaining mutations. But the pervasive occurrence of recoded stop codons, and the backchannel crosstalk between microbes and viruses, paints a more intricate picture of multilingual genetic instructions.”

Jelly genome mystery“The uniqueness of this ctenophore’s nervous system leads Moroz and his team to argue that it must have evolved independently, after the ctenophore lineage branched off from other animals some 500 million years ago.”

Genomic divergence in a ring species complex“Ring species provide particularly clear demonstrations of how one species can gradually evolve into two, but are rare in nature…. Here we use genome-wide analyses to show that, although spatial patterns of genetic variation are currently mostly as expected of a ring species, historical breaks in gene flow have existed at more than one location around the ring, and the two Siberian forms have occasionally interbred.” – h/t razib!

Natural selection and infectious disease in human populations“The ancient biological ‘arms race’ between microbial pathogens and humans has shaped genetic variation in modern populations, and this has important implications for the growing field of medical genomics. As humans migrated throughout the world, populations encountered distinct pathogens, and natural selection increased the prevalence of alleles that are advantageous in the new ecosystems in both host and pathogens. This ancient history now influences human infectious disease susceptibility and microbiome homeostasis, and contributes to common diseases that show geographical disparities, such as autoimmune and metabolic disorders.”

High genetic differentiation between populations often driven by classic selective sweeps“‘We demonstrate that while sites of low differentiation represent sampling effects rather than balancing selection, sites showing extremely high population differentiation are enriched for positive selection events and that one half may be the result of classic selective sweeps. Among these, we rediscover known examples, where we actually identify the established functional SNP, and discover novel examples including the genes ABCA12, CALD1 and ZNF804, which we speculate may be linked to adaptations in skin, calcium metabolism and defense, respectively. Conclusions: We have identified known and many novel candidate regions for geographically restricted positive selection, and suggest several directions for further research.'” – @dienekes’.

Mendelian-Mutationism: The Forgotten Evolutionary Synthesis – h/t neuroskeptic! who tweeted: “Did geneticists ‘crack’ the secret of evolution much earlier than believed?”

this one’s for linton!: Why Marrying Your Cousin May Pay Off“In line with previous findings, the researchers found that among non-foraging societies, a couple’s relatedness was linked with having more surviving children. But among foraging societies, the opposite was true: More-closely related spouses had fewer surviving children. Furthermore, the more family intermarriage in a society, the greater the benefit of intermarrying on the number of children couples had. In other words, in societies in which people frequently married their relatives, intermarrying showed a stronger link to having more children.”

The Closest of Strangers“[I]dentical twins who are aunts and uncles invest more in caring for the children of their twins (their ‘genetic’ sons and daughters) than do fraternal twins.”

Why Do Honor Killings Defy the First Law of Homicide? And Will Smaller Families Lead to Fewer Of Them? – h/t tom farsides! – previously: inclusive inclusive fitness.

Genetic and educational assortative mating among US adults“We find that spouses are more genetically similar than two individuals chosen at random but this similarity is at most one-third the magnitude of educational similarity.”

Irish fair skin can be traced to India and the Middle East“A major new US study at Penn State University has found that Europeans’ light skin stems from a gene mutation from a single person who lived 10,000 years ago…. Keith Cheng from Penn State College of Medicine reported that one amino acid difference in the gene SLC24A5 is a key contributor to the skin color difference between Europeans and West Africans…. ‘The mutation in SLC24A5 changes just one building block in the protein, and contributes about a third of the visually striking differences in skin tone between peoples of African and European ancestry, he said…. The mutation, called A111T, is found in virtually everyone of European ancestry. A111T is also found in populations in the Middle East and Indian subcontinent, but not in high numbers in Africans. All individuals from the Middle East, North Africa, East Africa and South India who carry the A111T mutation share traces of the ancestral genetic code. According to the researchers, this indicates that all existing instances of this mutation originate from the same person.” – h/t 23andMe!

The puzzle of European hair, eye, and skin color“The physical appearance of Europeans seems to result from a selection pressure that acted primarily on women and only secondarily on men. This is especially true for highly visible traits on or near the face—the focus of visual attention.” – from peter frost.

The Dark Triad of Personality – special issue of Personality and Individual Differences. – h/t claire lehmann!

Heritability of brain volume change and its relation to intelligence“Human brain volumes change throughout life, are highly heritable, and have been associated with general cognitive functioning…. Results show that changes in volumes of total brain (mean=-6.4ml; -0.5% loss), cerebellum (1.4ml, 1.0% increase), cerebral white matter (4.4ml, 0.9% increase), lateral ventricles (0.6ml; 4.8% increase) and in surface area (-19.7cm2, -1.1% contraction) are heritable (h2=43%; 52%; 29%; 31%; and 33%, respectively). An association between IQ (available for 91 participants) and brain volume change was observed, which was attributed to genes involved in both the variation in change in brain volume and in intelligence. Thus, dynamic changes in brain structure are heritable and may have cognitive significance in adulthood.”

Cognitive abilities amongst the Sámi population“Lapps have an IQ around 100.8 are tilted towards visuospatial ability and away from verbal ability.” – from elijah armstrong, michael woodley the younger, and richard lynn. edit: original paper here on elijah’s blog! (^_^)

The Flynn Effect in a Nutshell – from elijah.

Does brain structure determine your political views?“‘People like to believe that their own political beliefs are rational, that they’re a sensible response to the world around them, so when we come along and say, “Maybe there are these predispositions, influential but perhaps not fully in your conscious awareness,” that’s not the way we like to view our own political beliefs.'” – h/t mr. robert ford!

Sex-Related Neuroanatomical Basis of Emotion Regulation Ability“Behavioral research has demonstrated that males have a higher capability of regulating their own and others’ emotions than females; however, little is known about the sex-specific brain mechanisms involved in emotion regulation ability…. we found the sex differences in the neuroanatomical basis of emotion regulation ability. Males showed a stronger positive relation between emotion regulation ability and regional gray matter volume (rGMV) in the right dorsolateral prefrontal cortex. In contrast, females demonstrated a stronger positive relation between emotion regulation ability and rGMV in an anatomical cluster that extends from the left brainstem to the left hippocampus, the left amygdala and the insular cortex.”

More Maps of the American Nations – from jayman.

Privilege and Morality“Our species isn’t good at nuance. The ‘privilege’ debate will and must take place in a morally charged context. It is not possible to sanitize the discussion by scrubbing it free of moral emotions. That is one of the many reasons why it is so important to understand what morality is and why it exists. It does not exist as a transcendental entity that happened to pop into existence with the big bang, nor does it exist because the Big Man upstairs wants it that way. It exists because it evolved.” – from helian.

Economic Growth & Human Biodiversity“Economic growth in lower-IQ countries does not invalidate either the reality of IQ differences between countries or the persistence of those disparities.” – from pseudoerasmus.

Good Fences: The Importance of Setting Boundaries for Peaceful Coexistence“Switzerland is recognized as a country of peace, stability and prosperity. This is surprising because of its linguistic and religious diversity that in other parts of the world lead to conflict and violence. Here we analyze how peaceful stability is maintained. Our analysis shows that peace does not depend on integrated coexistence, but rather on well defined topographical and political boundaries separating groups, allowing for partial autonomy within a single country. In Switzerland, mountains and lakes are an important part of the boundaries between sharply defined linguistic areas. Political canton and circle (sub-canton) boundaries often separate religious groups. Where such boundaries do not appear to be sufficient, we find that specific aspects of the population distribution guarantee either sufficient separation or sufficient mixing to inhibit intergroup violence according to the quantitative theory of conflict. In exactly one region, a porous mountain range does not adequately separate linguistic groups and that region has experienced significant violent conflict, leading to the recent creation of the canton of Jura.”

Was Territoriality Important in the Pleistocene? A Commentary on Johnson and Toft – @peter turchin’s.

Southern Europe is suspicious: the evolution of trust in the EU – ess and wvs results.

Trust and In-Group Favoritism in a Culture of Crime [pdf] – h/t ben southwood! who tweeted: “Areas in Palermo with high Mafia involvement have lower generalised trust but higher in-group favouritism.”

In dogs’ play, researchers see honesty and deceit, perhaps something like morality – woof!

What is Phonemic Diversity? — And Does It Prove the Out-of-Africa Theory? – h/t james winters!

How a Protestant spin machine hid the truth about the English Reformation“It seems that in 1533, the year of Henry’s break from Rome, traditional Catholicism was the religion of the vast majority of the country. And in most places it was absolutely thriving. It had developed a particularly English flavour, with a focus on the involvement of ordinary people in parish churches, village greens, plays, and pageants – much of which seemed to involve a good deal of community parties, dancing, and drinking. It is true that English religion in the early 1500s was not especially studious or erudite. The people did not spend hours a day in biblical studies, contemplation, and moralising in the manner of the more intense European reformers. But England had a nationally cohesive spirituality that was alive and exuberant, with a distinctly community feel…. The conclusion of this modern grassroots scholarship is that bulldozing the Catholic Church off the face of medieval England was not a ‘bottom up’ revolution in which Henry merely acquiesced to his people’s wishes by throwing off a widely hated foreign domination. To the contrary, it looks increasingly like Henry and his circle imposed the Reformation ‘top down’, unleashing 100 years of deep anger and alienation that was only overcome by sustained politicking and ruthless force.” – h/t william briggs!

bonus: “No Oxygen? No Problem!” Says Squid That Can Shut Down Its Metabolism – h/t kyle hill!

bonus bonus: A Theory on How Flightless Birds Spread Across the World: They Flew There

bonus bonus bonus: Chicken project gets off the ground“Effort aims to unravel the history of bird’s domestication.” – cluck!

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clannishness paradox?

i think that i’m maybe — maybe — starting to notice a paradoxical pattern in clannishness. maybe. time will tell.

and the paradox is: on the one hand, we have peoples who behave clannishly generally favoring their close and extended family members (when they actually live amongst them) over the broader society (the commonweal) — egs. nepotism, corruption, feuding, etc. but on the other hand, i think that those very same clannish people are often more willing than non-clannish peoples to sacrifice one of their own under certain circumstances — it seems especially when it will benefit themselves and/or other members of the extended family/clan. i could be wrong about this. data needs to be compiled.

some examples:

– honor killings: as were discussed in yesterday’s post. and we know from before that honor killings — which are pretty extreme as far as sacrificing a member of the family goes — are most common in the arab world/maghreb/mashriq/afghanistan+pakistan where father’s brother’s daughter (fbd) marriage is preferred and has the highest rates — and fbd marriage pushes towards the highest inbreeding rates.

– the pashtuns: fbd marriage practitioners again. here’s a pashtun proverb via steve sailer:

“When the floodwaters reach your chin, put your son beneath your feet.”

presumably that’s not meant to be taken literally — presumably! but it does sound rather indicative of a willingness to sacrifice even one’s kids if necessary.

– the myddletonians: a middling clannish population from shropshire, england, in the seventeenth century (see here):

“Though placed toward the back of the church, tenant farmers, particularly those who boasted generations of ancestors in the parish, held much honor. They lost this honor, however, if they suffered rituals of public humiliation. So while often ignoring private vices, tenant farmers always made an effort to prevent overt mortifications. Worried middling parents sent their juvenile delinquents far from the surrounding countryside, not to rehabilitate them spiritually or even to save their skins, but to remove their likely and shameful jailings and hangings from the sight and recording of neighbors. A Myddle tavern-keeper, Thomas Jukes, exiled a larcenous son by placing him into apprenticeship with a roving juggler who happened to pass through the village. Michael Brame, of a long-standing Myddle family, came to Myddle following the death of his brother and brother’s wife in order to preserve the family’s leasehold and also to raise his brother’s son William. William robbed meat from several neighbors’ houses. The Braine clan took the only possible action: ‘at last he was sent away,’ noted Gough, ‘I know not whither.’”

disowned. in a serious way!

this all seems rather counter-intuitive — you’d think that clannish peoples would be less willing to sacrifice one of their family members since, most of the time, they seem overly concerned about favoring them. i mean, that’s why their societies are so dysfunctional (to different degrees). but i think it makes a sort-of upside-down-and-backwards sense if you think of these behaviors as altruistic in the strictest biological sense of the word. these behaviors are an example of “inclusive inclusive fitness,” i think. from yesterday’s post:

“you’re not sacrificing your *own* fitness to benefit another’s (whose genes you share), you’re sacrificing *someone else’s* — but you share a lot of genes with them, too, so in a way you *are* sacrificing the fitness of your own genes, just not those in your own person.”

another clannishness paradox that i’ve mentioned before is that individuals from clannish societies often feel very independent. here, for example, is taki on the greeks:

“The highly individualistic Greek is too self-seeking to submit easily to others’ dictates. His unruliness has helped him survive through the centuries of oppression, as well as to rise above adversity. But it has also made him unaware of the advantages of a communal spirit and true democratic attitudes. This has created a climate where cheating is a way of life, where the highest and lowest of citizens do not hesitate to use dishonesty, especially in politics.”

yeah. well, the misunderstanding there is that greeks are “individualistic.” they’re not. they’re clannish. and because they’re clannish, they don’t like outside interference — they’re not going to “submit easily to others’ dictates” and they’re certainly not going to have “a communal spirit and true democratic attitudes.” clannish people — like southern libertarians — don’t want outside interference (like from the gub’ment), so they seem individualistic, but what they are, in fact, is independent-minded — but in a clannish sort of way. the true individualists — the non-clannish peoples — tend to be communally oriented. and they are rare.

paradoxical, no? (^_^)

anyhoo — Further Research is RequiredTM.

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family honor, honor killings, and family likeness

something greying wanderer said recently (thanks, grey!)…

I think at a bare minimum there’ll be family resemblance which on average ought to be increased by inbreeding through linkage effects. I’m not sure if that’s generally accepted or not?”

…got me to thinking about family honor, honor killings, and family likeness.
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first of all, family honor: i haven’t done a systematic study of it yet, but all indications are that family honor is more important — oftentimes much more important — in long-term inbreeding societies than long-term outbreeding ones. family honor expresses itself in behaviors like feuding and honor killings. many of the usual suspects are included here (from wikipedia):

– the middle east – noted example, the bedouins
– turkey
– south asia: afghanistan, pakistan, and india
– china and japan: not so much honor killings as not disgracing the family by failing your exams!
– europe: the mediterranean region – “In Italy, infidelity of women was seen dishonorable, thus crimes of passion were classified as second-degree murders until 1970s.” (from here.)
– the old south (u.s.a.)
– hispanic cultures – including brazil.

and about honor in northern european societies (from here – my emphasis):

“[I]n Northern Europe it has a more individualized meaning that is focused on personal accomplishments and qualities.”

mmm-hmmm.

anyway, so i think it’s pretty safe to bet that family honor issues go together, for whatever reasons (i have my own ideas on the matter, of course), with long-term inbreeding. we’ve seen before that honor killings really seem to be connected to father’s brother’s daughter’s (fbd) marriage, which is mostly practiced in the arab world/north africa/middle east/parts of south asia and which pushes towards greater degrees of inbreeding (than other forms of cousin marriage).
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what about family likeness then? do the members of long-term inbreeding families look more like one another, on average, than the members of long-term outbreeding families? do they share more personality traits with one another? do they behave, on average, more like one another? i don’t know — and i don’t know of any research looking into these questions (anybody?).

remember the ghoul family though (hope they’re ok! =/ ) and how similar the brothers look to one another?:

ghoul brothers

are they indicative at all of what you get with long-term inbreeding? i really don’t know.
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but let’s assume, just for the sake of argument, that the members of long-term inbreeding families are more like one another on average than the members of outbreeding families, and that the likeness is not just in appearance but also in personality traits, behaviors, etc. perhaps this (if it’s true) might help explain honor killings.

family honor, at least with regard to honor killings, is a public thing. from what i’ve read — and i’m sorry that i don’t have any references at hand at the moment — honor killings usually happen when the trangression becomes publically known, or at least becomes known outside the immediate family. in societies where family honor is important, people don’t typically kill their errant daughters if they can keep their bad behavior a secret — that would be a waste of all the time and effort and money invested in raising her, and it obviously must be emotionally a very difficult thing to do (although maybe the family honor feelings over-ride that to some extent?).

honor killings are a sort of altruistic act, and i mean altruistic in the scientific meaning of the word (from here)…

“[A]ltruism refers to behaviour by an individual that increases the fitness of another individual while decreasing the fitness of the actor.”

…but in the case of honor killings, the altruistic behavior of the actor (the person who kills the daughter) doesn’t result in the decreasing of the actor’s own fitness, but, rather, the daughter’s (obviously). and, then, it’s the fitness of other members of the family that would be increased, namely any young family members who are of reproductive age or younger, since if the family honor is tarnished, it will be difficult, if not impossible, to get spouses for the other children. i half-jokingly referred to this before as “inclusive inclusive fitness” — you’re not sacrificing your own fitness to benefit another’s (whose genes you share), you’re sacrificing someone else’s — but you share a lot of genes with them, too, so in a way you are sacrificing the fitness of your own genes, just not those in your own person.

what if the underlying reason driving honor killings is because, in inbred societies, everybody knows from loooong experience that family members are really *very* like one another, so then, of course, you’d NEVER marry your kid to a member of THAT family because they had that one daughter who behaved very badly, and — conclusion — the rest of the family is probably like that, too?! maybe it’s crucial, then, for a family in an inbreeding society to distance itself from its badly behaving member by sacrificing her (and it usually is a her) in order to show the rest of society that the remaining members of the family do NOT condone the behavior and, implying, that they would never, EVER behave that way themselves.

don’t know. just an idea.
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see also: Family honor and Cultures of honour and cultures of law

previously: father’s brother’s daughter marriage and why fbd marriage amounts to more inbreeding than mbd marriage and father’s brother’s daughter (fbd) marriage and honor killings and inclusive inclusive fitness and mating patterns, family types, social structures, and selection pressures

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father’s brother’s daughter (fbd) marriage and honor killings

i took this table from the recent pew survey of muslims

honor killings permissible - pew 2013

…and made a couple of maps (adapted from this map).

the first one is a map of the differences between what percentage of muslims in each country responded that honor killing is never justifiable when a man commits an offense versus a woman committing an offense. a plus number (+) means more enthusiasm for honor killing women — a negative (-), men. here it is (click on image for LARGER view):

map of expansion of caliphate - pew honor killings diffs

what i think we can see is that, the closer you get to the arab expansion epicenter (the arab peninsula), the greater the enthusiasm for honor killing women. so in jordan it’s +47, lebanon and egypt +10, iraq +11. but when you get out to the edges of the caliphate, the differences are not so great, or they are in fact reversed: morocco -1, turkey and afghanistan and tajikistan 0. even pakistan is only +3. when you get way out to uzbekistan and kyrgyzstan, then the numbers are reversed: -14 and -3.

(it should be noted that for some reason the question was worded differently in uzbekistan, afghanistan, and iraq. everyone else was asked specifically about premarital sex/adultery and family honor, while the uzbekis, afghanis, and iraqis were only asked about family honor. see questions 53 and 54 here [pdf].)

i think that perhaps this is a reflection of what korotayev noticed, i.e. that father’s brother’s daughter (fbd) marriage is found in those places of the world that were a part of the eighth century muslim caliphate, because those populations wanted to emulate the arabs, and the arabs practiced fbd marriage. the reason that the populations on the edges of the caliphate are less enthusiastic about honor killing women is that they were arabized less and/or later than (dare i say it) the “core arabs” and so probably have been practicing fbd marriage for a shorter amount of time. (in fact, korotayev and other russian anthropologists suggest that fbd marriage started in the levant and moved southwards into the arab peninsula, so some of the jordanians and lebanese may have started practicing fbd marriage before the arabs down in the peninsula.)

i think, too, that there is a connection between fbd marriage and honor killings, because fbd marriage leads to greater inbreeding, and greater amounts of inbreeding may very probably lead to greater frequencies of “genes for altruism” — and honor killings can be viewed as a sort-of upside-down-and-backwards form of altruism (at least they seem that way to us).

and/or the arabs simply introduced some crazy “genes for upside-down-and-backwards altruism” to these various populations, and less so on the fringes presumably because not so many arabs actually made it that far. edit: also interesting to note is that in fbd societies, all of the men in extended families/clans share the same y-chromosome. if there is a connection between violence and some gene(s) on the y-chromosome (i thought greg cochran said something about this, but i can’t find it now), maybe this is exacerbated by fbd marriage.

here is the other map — the percentage of muslims in each country responding that it is rarely, sometimes, or often justified to honor kill women:

map of expansion of caliphate - pew honor killings women

again, the numbers taper off on the edges of the extent of the caliphate.

previously: father’s brother’s daughter’s marriage and inclusive inclusive fitness and who wants sharia?

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who wants sharia?

pew has just released the results of their latest survey of muslims around the world (in 39 different countries).

here’s a map showing the percentage of muslims in each country that would like sharia to be the law of their land (click on map for LARGER image – should take you to the pew site):

who wants sharia - pew 2013

the iraqs, afghanis, and pakistanis all seem pretty eager for sharia — they’re all in the 75-100% range. the moroccans, too. and the palestinian territories.

this is a large report from pew, so have a look at the whole thing yourself.

here’s something else that i found particularly interesting:

honor killings permissible - pew 2013

of the countries that think that honor killing is more justified when women commit an offense than when men do — russia, albania, azerbaijan, bangladesh, pakistan, jordan, iraq, egypt, lebanon, tunisia, and the palestinian territories — a majority of them (7 out of 11) have a preference for father’s brother’s daughter’s (fbd) marriage — pakistan, jordan, iraq, egypt, lebanon, tunisia, and the palestinian territories.

i don’t know what, if any, form of cousin marriage is preferred in azerbaijan or bangladesh. paternal cousin marriage, which would include fbd marriage, is avoided in places like chechnya and (at least among some peoples in) dagestan (russia in this survey?) and albania. the difference in the responses in albania was not very great (+1 point), but the difference in russia(?) was statistically significant at +7 points. it’s difficult to know who these “russian” muslims are (maybe the info is in an appendix somewhere — i’ll have to look), so i don’t know if they’re the chechens and/or some dagestanis and/or some other group(s) — and, so, i don’t know what their mating patterns are.

i’m surprised that afghanistan breaks even. i would’ve predicted that they would be like the other fbd marriage groups.

it’s interesting that some of the central asian “stans” — kyrgyzstan and uzbekistan — swing in the opposite direction. a greater number of people feel that honor killings are more justified against men who break the rules than women. i don’t know much of anything about these populations, but i did read a bit just the other day, and it seems that they have a preference for maternal cousin marriage. (note that i don’t have a good idea what the rates might be.)

previously: inclusive inclusive fitness

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inclusive inclusive fitness

inclusive fitness means you can increase your own (genes’) fitness by somehow being altruistic to other individuals out there who share your genes, family members being the most obvious choice (’cause they typically share a lot of your genes — especially if you’re a bee). an altruistic behavior is defined in biology as some action which helps out another individual(s) while costing the altruistic individual a chance at reproducing or even surviving.

let’s take my example from my last post on altruism: the suicide bomber. the suicide bomber makes the ultimate sacrifice — 100% of his genes on behalf of, presumably, some or all of his extended family members. here he is — mr. light-blue square. by blowing himself up — and possibly taking some of his family’s enemies’ genes with him — he forfeits all of his genes, outlined in red, that are found in his own genome:

but, there are other copies of his genes in other people — that’s kinda the whole point.

now, remember mr. light blue and miss light pink from this post? well, here they are again. they’re first-cousins so (barring any other inbreeding) they prolly share 1/8th of their genes in common, thus they overlap:

and here, they’ve mated and had a daughter, miss deep-pink, who has inherited half of her father’s chromosomes and half of her mother’s, but she’s gotten some duplicate copies of genes (alleles) because her parents shared genes (alleles) in common (i.e. where they overlapped). (like her brother, mr. deep-blue, she’s “less of an individual” than an outbred person.):

i’ve purposefully picked first-cousin marriage here because i want to take a look at another example of altruism from the muslim world — honor killing (i know — honor killings are not restricted to muslim societies).

what happens genetically when a parent — or often parents — kills one of his kids?

well, in the suicide bombing example above, the individual sacrificed 100% of his genes for his family. in the case of honor killing, he sacrifices half of his genes for his family plus the extra copies of his genes/alleles that his daughter carries due to the inbreeding — according to my calculations, that means he’s sacrificing (prolly) 56.84% of his genes (in an fbd marriage scenario, which is a typical cousin-marriage pattern found in the muslim world). (all of this can be flipped around to view it from the mother’s p.o.v., obviously.) here again, outlined in red, are the genes that he altruistically sacrifices.:

it doesn’t really matter if he sacrifices his genes within his own genome or his genes within his daughter’s genomeeither way, he’s still sacrificing some of his own genes for a greater number of his own genes found in other individuals.

and 56.84% vs. 100%? — honor killing is clearly an altruistic bargain compared to suicide bombing. =/

also, in the honor killing situation, dad’s still around to live another day and possibly even reproduce some more. still, it is something to sacrifice the young who probably have before them more opportunities to reproduce than dear old dad. they are the future, obviously. (i’ve read somewhere that honor killings often or typically take place when whatever the scandal is becomes publically known — otherwise, of course, a family will try to cover things up. why sacrifice a family member if you don’t have to? unfortunately, can’t find the reference where i read that. pretty sure it was daniel pipes.)

but who is benefitting from this altruistic killing? well, westerners often belittle the claims that muslims and other peoples make when they say that they’re saving their familiy’s honor in murdering a daughter (or two or three) — but if your other children are unable to marry** because of one child’s bad behavior, then obviously honor killing becomes an altruistic act, since in total you will benefit a greater number of your genes by sacrificing some of them. that’s the biological definition of altruism.

honor killings are really an example of inclusive inclusive fitness since the altruistic individual’s genes that are sacrificed on behalf of copies of his genes in other individuals are other copies of his genes in other individuals. (got that?)

the long history of inbreeding in middle eastern/north african/south asian muslim societies is important here, too, ’cause remember — inbreeding means that the evolution of altruism in a population is made easier. whatever genes that influence the willingness, for ultimately altruistic reasons, to kill an offspring, a pretty extreme step — genes that make individuals within these societies, on average, more willing to do it than otherwise — seem to have arisen and flourished in these populations, undoubtedly because of their particular evolutionary history.

no, of course i’m not condoning honor killings — or any other kind of killing for that matter (self-defense is ok). i’m only trying to explain them. by understanding where the drive for them comes from, maybe people can put an end to them (if they want to).

**remember how in “Pride and Prejudice,” miss elizabeth bennett fretted that that she and her other sisters would have difficulties marrying because of the disgrace lydia brought on the family…?

previously: which altruism genes?

(note: comments do not require an email. can’t think of anything funny to say about honor killings. =/ )