Archives for posts with tag: subsaharan africa

i’ve been trying to think through polygamy and if there’s any potential there for the selection for clannishness like i think there is with long-term cousin marriage. (i think i might have sprained a parietal lobe while doing so. (*^_^*) ) i very much have subsaharan african societies in mind here, but, of course, polygamy occurs elsewhere, too.

on the surface it seems obvious that long-term polygamy ought to set the stage for the possible selection for clannish behaviors like cousin marriage (imho) does. like repeated cousin marriage, strict polygamy ought to narrow the relatedness within a population — the result of strict polygamy should be a greater number of half-siblings in a population than in a randomly-mating population, and, of course, half-siblings are more closely related to one another than non-siblings, so a society full of half-siblings could potentially lead to an accelerated selection for nepotistic altruism in a way similar to cousin marrying societies.

however, one big difference is that in polygamous societies generally — even in subsaharan african societies (where there’s a lot of polygamy) — people do not marry/mate with their half-siblings. (it does occasionally happen in some subsaharan societies, but only occasionally.) so, unlike in cousin-marriage societies, “genes for nepostistic altruism” (whatever they might be) might *not* become concentrated in family lineages. yes, there are a lot of half-siblings in polygamous societies, but any particular nepostistic altruism (“clannishness”) genes they might have (gotten from their fathers) will get diluted as they move out into the general population and marry non-relatives. if polygamy isn’t a driver of accelerated selection for nepotistic altruism (and i’ve rather persuaded myself that it isn’t), that could explain why subsaharan africans are generally pretty civic-minded, comparatively speaking. (the poor outcomes seen in african nations are perhaps more the result of other factors like low iq, high disease rates, etc., rather than clannishness. dunno. Further Research is RequiredTM.)

i should note here that polygamy in subsaharan africa is extremely variegated — in some societies, it’s typical for the first wife to actually be a cousin, and then the rest not. so there can be a layer of cousin marriage in amongst the polygamy. in other societies, cousin marriage is completely avoided. in yet other societies, the series of wives might be sisters (sororal polygyny), which makes all the offspring not only half-siblings (because they have the same father) but also cousins (because their mothers are sisters). here you would think that any selection for nepotistic altruism should very much be amplified. of course, in many subsaharan african societies — especially the polygamous ones — there’s often a lot of hanky-panky going on, so not all of the siblings will truly be half-siblings, etc. that’ll dilute your genes for nepotistic altruism right there.

another thing i also thought of regarding subsaharan and/or polygamous societies is the fact that all of the half-siblings don’t always grow up together. in patrifocal polygamous societies, yes — there you’ll have one man living with all of his wives (poor fellow!) and all of his kids, so all the half-siblings will be raised in the same place and interact with one another — and, presumably, continue to do so as adults. in matrifocal societies, a mother and her children reside with the mother’s family, not her husband and his family. this occurs in some polygamous societies, too.

it seems to me that, even if polygamy was a driver of accelerated selection for nepotistic altruism, such selection couldn’t possibly happen if the carriers of the clannishness genes don’t interact. if the half-siblings from polygamous unions don’t grow up together, or don’t interact much as adults, but rather with their (ordinary, i.e. not inbred) cousins, how would clannishness be selected for? it wouldn’t, i don’t think. or it wouldn’t be selected for in an amplified, accelerated way (which is what i think happens in the long-term cousin marriage scenario).

and that’s as far as i got with thinking through polygamy (i shall return to this topic, i’m sure). but thinking about the patrifocal vs. matrifocal family types got me to thinking about something else.

thought experiment: let’s say you eliminate cousin marriage from a population, but don’t eliminate the extended family. say you get rid of the inbreeding, but individuals continue to interact mostly with their close (extended) family members — more so than with the other members of society who are unrelated to them. you would think that it would take longer for clannishness to disappear — for “genes for nepostistic altruism” to get diluted in the population — than in a society where both cousin marriage AND the extended family were simultaneously eliminated.

i am, of course, talking about medieval western versus eastern europe here. the extended family was eliminated quite early in the middle ages in western europe via manorialism along with cousin marriage (serious changes to both were well underway in western europe by the 800s). in eastern europe, the cousin marriage bans appeared later simply because christianity had arrived later. and, especially the further east one goes (like into russia), the fewer pressures there were to eliminate the extended family. quite the opposite, really. for example, this was the situation in the baltic regions, including belorussia, in ca. the fifteenth century [pg. 440]:

a “…’kinship holding’, was collectively held by the extended family. Rural settlements often contained more than one kinship holding, and each holding was in turn subdivided among smaller households within the extended family….”

and in russia as late as the late seventeenth and early eighteenth centuries [pg. 444]:

“Russian manorialism was distinctive in several important ways…. In Russia…it was the peasant commune that allocated these taxes and obligations among the households. The village commune in Russia had emerged in the late seventeenth or early eighteenth centuries in response to increasing demands from the state and the landowning elite; peasant communes not only allocated obligations, but also chose their officials, held court, selected recruits for conscription levies, and kept written records of their activities. The communal clerk was sometimes the only member of his commune who could read and write….

“[O]n Russian manors, where hired labour was often not available, the peasant family had to personally perform labour obligations at the same time that it worked its own farm. This required large, often multi-generational, households with enough labour capacity to serve the simultaneous needs of both the manorial economy and the family farm…. As Steven Hoch has shown, however, life in the large household was hardly a rural idyll; household patriarchs formed a communal elite that ruled with despotic brutality, ruthlessly exploiting their families and denying any autonomy to the adults under them. At the same time, however, the large household also protected the peasant family from ruin.”

(hmmm. ever wonder where the russian love for [left-wing] authoritarianism comes from?)

even if eastern europeans/russians began to avoid cousin marriage around, say, 1000 (conversion to christianity), they didn’t quit residing in extended families and mostly interacting with their extended family members until, like, yesterday. (again, this pattern appears to be more pronounced the further east one travels.) so the dilution of nepotistic altruism genes in eastern european populations — via nepotistic behaviors being misapplied to individuals not sharing the same altruism genes (i.e. unrelated individuals) — didn’t happen as quickly as it did in western europe where people began regularly interacting with non-kin much earlier in the middle ages.

family types matter.

that’s all i’ve got for you for now. more soon! (^_^)

previously: start here and cousin marriage in sub-saharan africa and fulani, hausa, igbo, and yoruba mating patterns

(note: comments do not require an email. russian peasants.)

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here’s a top ten-ish selection of my posts from this year, selected by me (this blog is not a democracy! (~_^) ). they weren’t necessarily the most read or most commented upon posts, but just the ones that i like the best and that i’d like people to read. ymmv!

a BIG thanks to all of you who do read the ol’ blog! and many, many thanks for all the informative and insightful comments. (^_^) …and for some of the crazy comments, too. (~_^)

big summary post on the hajnal line“so, apart from indicating patterns of nuptuality in late medieval and modern europe, hajnal’s line also represents the extent of both manorialism and The Outbreeding Project on the continent. both of these together set up a very new and different sort of social environment for western europeans — a new, and quite unique, social environment which exerted some very different sorts of selection pressures on the populations, particularly on social behaviors, but perhaps on other traits as well.”

medieval manorialism’s selection pressures“medieval society in northern europe (ca. 400-1500 a.d.) produced some quite unique selection pressures which very much shaped the characteristics and personalities of ‘core’ europeans….”

die ostsiedlung“from a sociobiological point-of-view, probably the most underappreciated event in recent western european history. that and the reconquest of spain.”

mating patterns of the medieval franks“by the 800s, second cousin marriages amongst the franks were considered ‘scandalous.’ bishops actively enforced the bans in their dioceses and neighbors willingly squealed on their cousin-marrying neighbors to the bishops. by the 800s-1000s, there is good evidence that both the frankish aristocracy and the lower classes avoided close cousin marriage.” — see also: kindreds, communes, feuds, and mating patterns in medieval france“beginning in the 1000s, there are indications — the rise of lineages and the appearance of communes — that the french kindreds were starting to break apart. however, feuding continued in france into the 1200-1300s, so clannishness did not disappear in france overnight.”

the transition from shame to guilt in anglo-saxon england (and “core” europe)“feelings of guilt were probably selected for over the course of the middle ages in northwestern europe starting in the early part of the period.” — see also: more on the origins of guilt in northwestern european populations“the center of the guilt culture in northwestern europe — the core region which (historically anyway) has been characterized by the least corruption, the highest levels of trust, liberal democracy, free societies, low levels of internal violence, high levels of human accomplishment, the invention of capitalism, the advancement of science, the development of the ideas and ideals of the enlightenment, and pretty much everything else we call western civilization today — is the core where The Outbreeding Project began the earliest in europe.”

sneak preview: violence, punishment, outbreeding, and swashbuckling pirates in medieval england“over the course anglo-saxon period…the death penalty did come to be more widely applied to cases of homicide, but for most of the period there weren’t really very many executions of killers…. more laws demanding the death penalty (or castration) for killings were issued and enforced during the anglo-norman and angevin periods… [but] executions actually remained comparatively low during large parts of the norman period…. as far as i can tell, criminals were executed right and left during the tudor period. the use of capital punishment really ramped up during the 1500s.” — see also: homicide rates in various regions of thirteenth century england“[I]t is possible that every person in England in the thirteenth century, if he did not personally witness a murder, knew or knew of someone who had been killed.”

a study in swiss“my guess is that the swiss are some of western europe’s ‘inbetweeners’ as far as outbreeding goes. i guessed that they probably got involved in The Outbreeding Project later than some other western europeans — the ones in and closer to the center of my ‘core’ europe. and they didn’t experience manorialism either (unless some of them on the swiss plateau did?).”

reverse renaissance?“perhaps the arabized world underwent a *reverse* renaissance process thanks to the introduction by the arabs of the most inbred form of cousin marriage — father’s brother’s daughter (fbd) marriage — to the populations of the middle east/maghreb….” — see also asabiyyah and asabiyyah ii – clannishness and the abbasid caliphate.

fbd cousin marriage and clans and tribes in iraq“i think a long term inbreeding society selects — or *can* select — for what i call clannishness. and iraqis have got that in spades. they’ve got clans and tribes, nepotism, and an obvious inability to handle liberal democracy. not that that’s some sort of goal in and of itself. i’m just sayin’.”

cousin marriage in sub-saharan africa“there is also a wide variety of mating patterns in ss africa. some populations avoid cousin marriage altogether. we’ve already seen this with the bamileke of cameroon and the igbo of nigeria. also the turkana of kenya and quite possibly the amhara of ethiopia (not 100% sure about them — need to double-check). a notable group which apparently avoids cousin marriage is the zulu. but plenty of other ss africa groups do practice cousin marriage like, as you’ll see in the table below, the kongo and luba in the democratic republic of congo, the ashanti in ghana, the sotho-tswana in south africa, and the kpelle of liberia.” — see also: the bamileke of cameroon and fulani, hausa, igbo, and yoruba mating patterns.

the american revolutions“that there were four american revolutions is a result of the fact that four (five?) somewhat different english populations settled in different regions of north america. the cultural and attitudinal differences between these regions persist to this day because, undoubtedly, there are genetic variations between the populations — probably average genetic differences in the frequencies of genes related to behaviors, personality, and even intelligence. these regional differences also persist because, since the very founding of the united states, like-minded people have been self-sorting themselves within the country so that they group together — and that sorting process has *not* been slowing down.”

it’s not nature and nurture…“…it’s nature and…*we dunno*…miscellaneous/unknown/noise?” — this post's actually very important. READ THIS POST! think about it for a while and let it sink in. and make sure to follow the links!

– my "what is hbd" series: what is human biodiversity (hbd)?“human biodiversity (hbd) is very simply the diversity found among and between human populations that has a biological basis.” — see also: what human biodiversity (hbd) is not; examples of human biodiversity (hbd); why human biodiversity (hbd) is true; hbd and racism; and hbd and politics.

– and finally: you and me and hbd“if you accept that humans exhibit biologically based diversity, then you’d better be prepared to accept ALL of it.”

previously: top ten list 2013

Zigzags on a Shell From Java Are the Oldest Human Engravings“The early human Homo erectus also made the oldest known shell tools half a million years ago.” — see also: The art of Homo erectus“What we can say is that these artifacts carry information about the capabilities of their makers. The few non-perishable marked objects also speak to the likely presence of design in perishable elements of material culture. Clothing, however rudimentary, was likely to have been decorated in some way. Wooden tools were also probably notched and zigzagged — as the occasional bone and ivory implements suggest. They lived for the first time in a world that they could change.” – from john hawks.

Genetic diversity of Sub-Saharan Africa revealed[T]he researchers also found that there were more genetic similarities across Africa than they had thought. Dr Sandhu said: ‘The diversity among populations is not as diverse as we expected it to be….’ The researchers found that many Africans have some Eurasian DNA within their genetic ancestry, which suggests that Eurasians migrated back into Africa many thousands of years after they first left. And several of the populations were descended from the Bantu, a group that spread across Africa about 5,000 years ago.” — see also: The African Genome Variation Project shapes medical genetics in Africa.

and here is dienekes on the above study: African Genome Variation project paper“In too many papers to count, decreasing genetic diversity from East Africa was taken as evidence of an origin of H. sapiens in that locality and its expansion from there to Eurasia. This ‘East Africa=cradle of mankind’ theory has, as far as I can tell, nothing really to stand on. Granted, the oldest anatomically modern human remains have been found in East Africa 200-150 thousand years ago. But, the fact that old sapiens have been found in East Africa and not elsewhere is easily explained by the excellent conditions for preservation (as opposed, e.g., deserts or rainforests of Africa or elsewhere), and by the extraordinary effort by palaeoanthropologists in that area. One also needs to overlook a century of physical anthropology that concluded that East Africa was a contact zone between Caucasoids and Sub-Saharan Africans. We now know that there is no deep lineage of humans in modern east Africans. Take out the Eurasian ancestry and only a paltry Fst=0.027 remains with other Sub-Saharan Africans, a fraction of the Fst between, say, Europeans and East Asians.”

Living African group discovered to be the most populous humans over the last 150,000 years“New genetic research reveals that a small group of hunter-gatherers now living in Southern Africa once was so large that it comprised the majority of living humans during most of the past 150,000 years. Only during the last 22,000 years have the other African ethnicities, including the ones giving rise to Europeans and Asians, become vastly most numerous…. ‘This and previous studies show that the Khoisan peoples and the rest of modern humanity shared their most recent common ancestor approximately 150,000 years ago, so it was entirely unexpected to find that this group apparently did not intermarry with non-Khoisan neighbors for many thousand years….'” — see also The Least Bottlenecked Humans of All from razib.

Ants, altruism and self sacrifice“It’s the selfishness of genes that makes us unselfish…. ‘Group selection’ has always been portrayed as a more politically correct idea, implying that there is an evolutionary tendency to general altruism in people. Gene selection has generally seemed to be more of a right-wing idea, in which individuals are at the mercy of the harsh calculus of the genes. Actually, this folk understanding is about as misleading as it can be. Society is not built on one-sided altruism but on mutually beneficial co-operation. Nearly all the kind things people do in the world are done in the name of enlightened self-interest. Think of the people who sold you coffee, drove your train, even wrote your newspaper today. They were paid to do so but they did things for you (and you for them). Likewise, gene selection clearly drives the evolution of a co-operative instinct in the human breast, and not just towards close kin.” – from matt ridley. — see also: E.O. Wilson’s The Social Conquest of Earth from jason collins. h/t billare!

Genetic Variation in Human DNA Replication Timing“Replication timing, a driver of locus-specific mutation rates, varies among humans…. Replication timing associates with common polymorphisms near replication origins….” – whoa.

Genetic and environmental exposures constrain epigenetic drift over the human life course – h/t casey brown! who tweeted: “Worth repeating: DNA methylation is more genetic than epigenetic.”

IQ is in the genes“How parents raise us has no impact on how smart we become, a new study finds.”

Link discovered between fathers’ criminal history and sons’ intelligence“Sons whose fathers have criminal records tend to have lower cognitive abilities than sons whose fathers have no criminal history, data from over 1 million Swedish men show. The research, conducted by scientists in Sweden and Finland, indicates that the link is not directly caused by fathers’ behavior but is instead explained by genetic factors that are shared by father and son.”

Are bright people normal?“‘We found no support for the genetic Discontinuity Hypothesis that nonadditive genetic variance is greater for high intelligence….'” – from dr. james thompson.

Booze culture may date back 10 million years say scientists“A new study suggests that primates may have begun drinking alchol 10 million years ago, as fermented fruit on the forest floor…. Experts at Santa Fe College in the US studied the gene ADH4 which produces an enzyme to break down alcohol in the body. It was hypothesised that the enzyme would not appear until the first alcohol was produced by early farmers. But scientists were amazed to find it 10 million years earlier, at the end of the Miocene epoch.” – (them’s *my* ancestors right there! (~_^) )

Psychiatry: End of the Road for “Endophenotypes”?“In a nutshell, the researchers ran seven different genetic studies to try to find the genetic basis of a total of seventeen neurobehavioural traits, also known as ‘endophenotypes’…. Essentially an endophenotype is some trait, which could be almost anything, which is supposed to be related to (or part of) a psychiatric disorder or symptom, but which is ‘closer to genetics’ or ‘more biologica’ than the disorder itself. Rather than thousands of genes all mixed together to determine the risk of a psychiatric disorder, each endophenotype might be controlled by only a handful of genes – which would thus be easier to find…. Over 89% of the searches came up null in this way; for eight of the seventeen traits, the researchers found no associated genes using *any* strategy.” – from neuroskeptic.

Unequal fates for maths superstars“The fates of US child prodigies of the 1970s reveal great accomplishments but strong gender differences…. [B]oth genders reported unusually high levels of satisfaction with their lives and careers. ‘It seems that both sexes got what they wanted from life, even if those things were somewhat different….'” – h/t charles! – see also: Sometimes men and women want different things from ben southwood.

Are Chinese babies more docile? – peter frost on the freedman studies.

Inferior Faunas – from greg cochran.

Transparency International’s Corruption Perceptions Index 2014 released this week.

Domestication and Human Evolution Symposium @getCARTA sessions now available to watch online.

Does evolution need a revolution? – from jerry coyne.

Experimentally induced innovations lead to persistent culture via conformity in wild birds – birds have culture.

A Magisterial Synthesis Of Apes And Human Evolution“[Russell H.] Tuttle’s tome is a grand synthesis of all the latest research and data about apes and their relation to us…. He believes that bipedalism preceded the development of the brain in early humans –and was likely something inherited from smaller apes already used to using their feet to move laterally along branches in trees. Although chimpanzees and bonobos are our closest relatives on the evolutionary tree, they do not represent in their own locomotion good proto-models of what led to human upright posture and walking.”

‘Superbugs’ Kill India’s Babies and Pose an Overseas Threat“A growing chorus of researchers say the evidence is now overwhelming that a significant share of the bacteria present in India — in its water, sewage, animals, soil and even its mothers — are immune to nearly all antibiotics.” – h/t razib!

The RNA World: molecular cooperation at the origins of life“The RNA World concept posits that there was a period of time in primitive Earth’s history — about 4 billion years ago — when the primary living substance was RNA or something chemically similar. In the past 50 years, this idea has gone from speculation to a prevailing idea. In this Review, we summarize the key logic behind the RNA World and describe some of the most important recent advances that have been made to support and expand this logic. We also discuss the ways in which molecular cooperation involving RNAs would facilitate the emergence and early evolution of life.”

Tool to edit DNA revolutionizing research in Boston area – CRISPR.

Thomas Docherty on academic freedom“Managerial fundamentalism has taken hold in universities, with scholars viewed as resources that must be controlled…. A creeping incremental assault on academic freedom threatens not just what can be spoken aloud, but also what it is permissible to think: thought itself is to be subjected to management, so that its critical power is neutered or constrained….”

The Dark Enlightenment for Newbies“So what is dark about the Dark Enlightenment? Absolutely nothing. The Dark Enlightenment only looks dark in contrast to the blinding (as in, it blinds you) optimism of flash in the pan of blank slate equalism. The things that the DE contend about human nature — that parents naturally favor their children, that sexual attraction is a biological phenomenon, that some people are naturally smarter than others — were all accepted as common sense for most or all of human history. It is the unrealistic utopianism of modern liberalism which is ridiculously absurd. The Dark Enlightenment might be better termed The Return to Normalcy. So the phrase “Dark Enlightenment” might not be the best, but it has received enough attention that I don’t think we should abandon it.” – very nice post from empedocles.

Tanzania evicting 40,000 people from homeland to make room for Dubai royal family“It will become a private hunting reserve” – =/ (i’m linking to salon!) – h/t john durant!

bonus: Why Some Mosquitoes Spread Malaria and Others Don’t“Sequencing the genomes of numerous Anopheles mosquito species from locations around the world has shown why some can carry and spread the deadly disease malaria while others don’t.” – h/t srikant mantri!

bonus bonus: Humpback Whales in the Arabian Sea Have Been Isolated for 70,000 Years

bonus bonus bonus: A diet to die for“One bird feasts on food that would leave most other animals stone dead.”

bonus bonus bonus bonus: Insect Swarms Go Critical“Scientists have found tantalizing evidence that diverse biological systems, including the human brain, gene expression networks, bird flocks, and fish schools, behave as though they are near the ‘critical point’ of a phase transition, like correlated spins in a magnet on the verge of ordering.” – h/t jayman!

bonus bonus bonus bonus bonus: Weird Physics Can Make an Invisible Cat Visible“These cat pictures are brought to you by quantum entanglement as discussed by Einstein and Schrödinger.”

bonus bonus bonus bonus bonus bonus: “The Feynman Lectures on Physics”, The Most Popular Physics Book Ever Written, Now Completely Online

bonus bonus bonus bonus bonus bonus bonus: Tette per la Scienza – boobies! (it really IS this time! (~_^) )

(note: comments do not require an email. quantum cats!)