A post by Manjunath Vadiari at Theories on past events provides a warning about taking the migration histories that testing companies provide along with genetic markers too literally. It's easier to sell a heritage than a set of numbers (this is what most people are paying for after all), but the history can be inaccurate, especially at low resolutions and when few subclades have been defined (especially common outside Europe). Manjunath, a Malayali living in Hyderabad, tested as Haplogroup R1 (M173), one of Eurasia's most common Y chromosome haplogroups, and got a "personalized" message from Spencer Wells describing his ancestors' journey from Central Asia to Europe. R1a is a very common haplogroup in places like Kyrgyzstan and Poland and R1b in Spain, England, and Ireland; the last two locations provide the Ys for a significant proportion of Genographic Project's R customers. The video form letter usually goes over well, but it doesn't quite work when it strikes an informed customer as profoundly unlikely.*
Apparently he got word back from Dr. Wells that instead he is R* (M207), a group ancestral to both R1 and R2, which is more common in South Asia. Still, be careful. This is an idea that has implications for all sorts of testing bias while data are slim. A Siberian D could easily get a story of her ancestors' settling of the Americas (really her very distant cousins') or an Ethiopian L3 of his forebears' journey out of Africa. Actually, nearly all of the literature focuses on what happened on the way out of Africa, rather than the very interesting things that happened *in* Africa (fortunately something that Wells himself is concerned about and working on). The results of your DNA test should be an evolving story**; its cladistics should show you a more complex (and thereby more accurate) story as you learn more and find closer and closer matches.
To say nothing about the limits of using only markers expressed in your *own* DNA, or of ascribing too much to *one* genetic identity... but I'll be talking about that forever, so it's not for this post.
* This is not the same as the "unlikely" of the uninformed customer who wouldn't immediately think of West African migrants to Britain becoming Yorkshire patriarchs as plausible, or Danish or Nigerien patrilineal descendants of Genghis Khan. Manjunath well knows that 35 kya Central Asians became ancestral to many migrations west, east, and south, and for a deep clade like R*, a move from Central Asia to Kerala via the Khyber Pass and Deccan is more likely than one that went all the way to Europe, then back.
I didn't mean that, seriously. The title came after the unintentional pun.
2007/04/04
2007/03/13
Tibetans not related to "yeti"
"All our analyses clearly indicate that the yeti is nested
several nodes within a specific ungulate group (i.e., the
perissodactyls, cf. Fig. 1) and, more specifically, forms a
subclade with sequences U02581 and X79547 (cf. figure
legend). These results demonstrate that extensive mor-
phological convergences have occurred between the yeti
and primates."
[PDF]
http://www.ulb.ac.be/sciences/ueg/pdf_files/yeti_1st_April04.pdf
2007/03/01
Genetic Chaos
Added to the blogroll: Genetic Chaos, a blog of abstracts and links to the full text of hundreds of papers "using genetic research to study human migration patterns."
2007/02/25
Prazeros and Boers: mestizaje, cultural exchange, and the ideology of identity
Knowing very little detail about the history of the former Portuguese East Africa, I hadn't heard about this before, a second relatively autonomous eighteenth century expansion of European settlement in Southern Africa away from the more rigidly controlled (by European colonial governments/companies) coasts. This seems to be analogous at first to Boers expanding inland from the Cape, but had a very different character than in the also largely autonomous Dutch agricultural settlement of the Cape Province:
Early in the seventeenth century, the Portuguese government began to acknowledge the rights acquired by these estate-holders[, private Portuguese individuals who acquired land title from the Mwene Mutapa]. After 1629, when the government obtained pseudo-legal sovereignty over the Mwene Mutapa's realm, it tried to regularize relations along lines that had initially been devised to promote settlement in Brazil....
These constraints were generally ignored. Some prazos [(estates)] grew in size until they covered a thousand square miles or more. Successive generations of prazeros married spouses who might be Africans, Indians, or members of other estate-owning families. By the nineteenth century, four or five family groups of mixed descent—we might almost call them clans—owned vast stretches of land on either side of the Zambezi River, from Chicoa to the Indian Ocean. These families wielded virtually unlimited power throughout the area. Neither the neighboring African rulers nor the Portuguese government were able to control them....
Indeed, historical studies by Allen F. Isaacman and M.D.D. Newitt have shown that the prazos became more like African chiefdoms as the years went by. The prazeros and their families continued to use Portuguese names and titles and to profess Christianity; but they were barely literate, they spoke local African languages more than Portuguese, they were polygynous, they believed in witchcraft, and they performed the functions of African chiefs, including in some cases the ritual functions. In this way the Portuguese elements were gradually assimilated into the local African culture.
Curtin, et al. African History: From Earliest Times to Independence. Harlow: Longman, 1995.
Just as in the Americas, attributing the differences between activities by different colonial powers (and their settlers) to European cultural factors like Catholicism, Protestantism, Germanic, or Mediterranean culture is naive and rings of both Eurocentrism and the even narrower species of such found among, surprise, northern Europeans with that insidious ideology of separatism called, among other things, apartheid. The Cape Province and the Zambezi Valley were very different places: the first relatively sparsely settled by isolated pastoral and hunting peoples, the other one of the main sources of gold for the rich Indian Ocean trade routes – among the artifacts at the ruins of Great Zimbabwe, even after Rhodesians melted most of the valuables down were pottery from Iran and China.
In the same way, Spanish centers in the Americas were only so large and successful because they built on the structure of indigenous empires, and, as with any relationship where cultural exchange is both possible and advantageous, whether European, colonial, and recorded or ancient, pre-colonial, and not recorded (such as the first Bantu settlement of the Zambezi over two millennia ago), it tends to occur. It is often very unequal, particularly when migrants are economically powerful men, but it occurs, and the endurance of the power structures, myths, and legends of these men is the source of many of our illusions about identity and history—whether of Aryan North India, the extinction of the Celtic English, Han Chinese homogeneity. or "racially" pure Afrikaners or white Southerners in the U.S. Not everything is an illusion: languages are replaced and made extinct, people are enslaved and killed (the prazeros on the Zambezi themselves were good at this), and certain material cultures replace others, but something almost always endures. When nothing else does, it's ancestry. History has proven over and over than perception of ancestry turns into the reality of identity, so getting it right is very important.
What the Cape Province and British-settled North America really seem to have in common is not so much Germanic myth inspired apartheid, as much as dominant elements in those societies have tried, but the political and ideological institution of the same pushing off those people who do mix (and/or acknowledge) mixing into a legally separate caste identity: in South Africa, Coloureds, who are mixed Dutch, Khoikhoi, Malagasy, and Indonesian (the latter two groups slaves brought in from the Indian Ocean basin), and in the United States, the mixed, yet black, results of the one-drop rule. Yet... people passed into socioeconomically dominant groups whenever they could, with the result that there are many Southerners who are part African and many Afrikaners who are part Malagasy and Khoi.
Previous explanations of the difference between, say, the United States and Mexico, have tended to focus on the supposed higher Spanish Catholic tolerance for mixing resulting in a mixed population, and the lower English Protestant tolerance resulting in a non-mixed population. i would prefer to say that the difference is rather the acknowledgement of mixing, and thus the society allowing it to continue to take place multigenerationally rather than for people to be pushed off into one group or another and thus gradually become phenotypically less alike.
This distinction is extremely important. It acknowledges that people really do tend to be recently mixed in all descents from seventeenth century settler societies, as autosomal DNA tests are beginning to show. This is relevant not just to populations who have long-term ancestry in settler societies founded in post-Columbian colonial efforts. Even if your parents migrated from Ethiopia to Canada thirty years ago (or, of course, never left Ethiopia at all); these are just among the best documented and socially relevant in today's global identity structures.
If the difference is ideology formed in the past, it can be nullified in ideology formed about the past. Genealogy, traditional combined with genetic, has an important role to play here, as our results and those of our cousins begin to show the reality of a world in which ancestry is never location-bound for far in the past.
Early in the seventeenth century, the Portuguese government began to acknowledge the rights acquired by these estate-holders[, private Portuguese individuals who acquired land title from the Mwene Mutapa]. After 1629, when the government obtained pseudo-legal sovereignty over the Mwene Mutapa's realm, it tried to regularize relations along lines that had initially been devised to promote settlement in Brazil....
These constraints were generally ignored. Some prazos [(estates)] grew in size until they covered a thousand square miles or more. Successive generations of prazeros married spouses who might be Africans, Indians, or members of other estate-owning families. By the nineteenth century, four or five family groups of mixed descent—we might almost call them clans—owned vast stretches of land on either side of the Zambezi River, from Chicoa to the Indian Ocean. These families wielded virtually unlimited power throughout the area. Neither the neighboring African rulers nor the Portuguese government were able to control them....
Indeed, historical studies by Allen F. Isaacman and M.D.D. Newitt have shown that the prazos became more like African chiefdoms as the years went by. The prazeros and their families continued to use Portuguese names and titles and to profess Christianity; but they were barely literate, they spoke local African languages more than Portuguese, they were polygynous, they believed in witchcraft, and they performed the functions of African chiefs, including in some cases the ritual functions. In this way the Portuguese elements were gradually assimilated into the local African culture.
Curtin, et al. African History: From Earliest Times to Independence. Harlow: Longman, 1995.
Just as in the Americas, attributing the differences between activities by different colonial powers (and their settlers) to European cultural factors like Catholicism, Protestantism, Germanic, or Mediterranean culture is naive and rings of both Eurocentrism and the even narrower species of such found among, surprise, northern Europeans with that insidious ideology of separatism called, among other things, apartheid. The Cape Province and the Zambezi Valley were very different places: the first relatively sparsely settled by isolated pastoral and hunting peoples, the other one of the main sources of gold for the rich Indian Ocean trade routes – among the artifacts at the ruins of Great Zimbabwe, even after Rhodesians melted most of the valuables down were pottery from Iran and China.
In the same way, Spanish centers in the Americas were only so large and successful because they built on the structure of indigenous empires, and, as with any relationship where cultural exchange is both possible and advantageous, whether European, colonial, and recorded or ancient, pre-colonial, and not recorded (such as the first Bantu settlement of the Zambezi over two millennia ago), it tends to occur. It is often very unequal, particularly when migrants are economically powerful men, but it occurs, and the endurance of the power structures, myths, and legends of these men is the source of many of our illusions about identity and history—whether of Aryan North India, the extinction of the Celtic English, Han Chinese homogeneity. or "racially" pure Afrikaners or white Southerners in the U.S. Not everything is an illusion: languages are replaced and made extinct, people are enslaved and killed (the prazeros on the Zambezi themselves were good at this), and certain material cultures replace others, but something almost always endures. When nothing else does, it's ancestry. History has proven over and over than perception of ancestry turns into the reality of identity, so getting it right is very important.
What the Cape Province and British-settled North America really seem to have in common is not so much Germanic myth inspired apartheid, as much as dominant elements in those societies have tried, but the political and ideological institution of the same pushing off those people who do mix (and/or acknowledge) mixing into a legally separate caste identity: in South Africa, Coloureds, who are mixed Dutch, Khoikhoi, Malagasy, and Indonesian (the latter two groups slaves brought in from the Indian Ocean basin), and in the United States, the mixed, yet black, results of the one-drop rule. Yet... people passed into socioeconomically dominant groups whenever they could, with the result that there are many Southerners who are part African and many Afrikaners who are part Malagasy and Khoi.
Previous explanations of the difference between, say, the United States and Mexico, have tended to focus on the supposed higher Spanish Catholic tolerance for mixing resulting in a mixed population, and the lower English Protestant tolerance resulting in a non-mixed population. i would prefer to say that the difference is rather the acknowledgement of mixing, and thus the society allowing it to continue to take place multigenerationally rather than for people to be pushed off into one group or another and thus gradually become phenotypically less alike.
This distinction is extremely important. It acknowledges that people really do tend to be recently mixed in all descents from seventeenth century settler societies, as autosomal DNA tests are beginning to show. This is relevant not just to populations who have long-term ancestry in settler societies founded in post-Columbian colonial efforts. Even if your parents migrated from Ethiopia to Canada thirty years ago (or, of course, never left Ethiopia at all); these are just among the best documented and socially relevant in today's global identity structures.
If the difference is ideology formed in the past, it can be nullified in ideology formed about the past. Genealogy, traditional combined with genetic, has an important role to play here, as our results and those of our cousins begin to show the reality of a world in which ancestry is never location-bound for far in the past.
2007/02/09
Review of Blood of the Isles / Saxons, Vikings, and Celts by Bryan Sykes
I just finished reading Blood of the Isles,1 by Bryan Sykes of Oxford University. Sykes styles himself a genetic archaeologist, and in this book he spends as much time on the historiography and mythography of identity in Britain and Ireland as he does on interpretation of DNA tests. The result is a book that should be included as a text in any general survey history of the British Isles. It is the first history that uses genetic material as its primary data set, and it works very well, coming from a scholar with interests as well-rounded as Sykes. He outlines the way migrations to the Isles have been thought of, from the polemics of sixth century monks to the absurdities of nineteenth-century racists, sets out hypotheses based on the more reasonable theories, then tests them through data, separately for Ireland, Scotland, Wales, and England. The conclusion, and it is a very important step for our understanding of history to take, is that the British and Irish are basically one people, the same as they were when they settled the Isles from Spain as the ice receded, with only minor impact from the names that history records, Celts, Romans, Saxons, and Vikings. The impact of these peoples, genetic in part, was mostly cultural and historical.
Yet it suffers from one important fallacy, the same that the most brilliant minds in genetics still make. Anyone who understands the numbers involved, and Sykes clearly does, is able to see that a male resident of Aran, let's say, of matrilineal clan Ursula (a woman who lived in Greece something like 45,000 years ago), and carrying the Y-chromosome of Somerled, the Gael who drove the Vikings from the Isles, does not just have these two as ancestral lines. In a population that includes hundreds or thousands of lineages (all populations) which does not limit marriage to within both patrilineal and matrilineal clans (no population I'm aware of), most lineages in the society will become ancestral to most individuals, given only a few generations. I have no doubt that Sykes understands this, but it's curious that he doesn't emphasis it. To me it is the *most* fascinating part of genetic genealogy. Genetic genealogy has the potetntial to forge a quick connection to both local and worldwide communities, not just a single or dual marker of heritage.
That man from Aran is not just descended from Ursula, but from all mitochondrial lineages surviving in his population and from many mitochondrial lineages now extinct, but which lasted long enough to be counted among his ancestors. The same is true of all current and all marginalized Y chromosome haplotypes. He carries his descent from Ursula and Somerled in his genes, true, and there's something very exciting about that, but it's his invisible lineages, traceable only through testing uncles or cousins, close and distant, that reveal his true nature as an individual who encompasses in his DNA the entire diversity of his society, both other common haplotypes and very rare ones. Traceable genes may not be in his mitochondria or Y chromosome, genes may not even have been inherited from these people at all, but his ancestry is far, far more complicated than a simple story that goes to the ends of the Mediterranean and then back to Africa. It all goes back to Africa, of course, but by 2lots routes, not 2.
I find it difficult to believe that Bryan Sykes has not thought this fallacy through. In Blood of the Isles, as throughout his popular work, Sykes strives to preserve the individual nature of data collected from his subjects' DNA, preferring to let stories, rather than statistics, emerge from the data. The first woman to carry a particular mDNA haplotype becomes a clan mother (his The Seven Daughters of Eve) instead of a number, and ubiquitous Y chromosome DNA lineages are traced, quite believably, to historical and mythological kings, warlords, and other such headmen. These are stories people can quite easily append to family histories that are much closer in time. Descent from Jasmine, the Syria-born matriarch of the Neolithic agricultural migrations into Europe, from Genghis Khan, or from Somerled, is a much more romantic notion than identity with R1B or O3 or H. It's certainly easier to talk about at the family reunion. Yet the essentially communal nature of genealogy brings in another question. Every nuclear family is made up of individuals of different matrilineal clan lineages, every extended family of many matrilineal and patrilineal ones. This is as easy a notion to understand as that a family can have many surnames. So why can't genetic genealogy explore it.
If I weren't confident that Sykes has science's best interests at heart, I would be cynical and say that he perhaps believes that Oxford Ancestors' coffers will be more easily filled if people feel they are getting a real sense of identity from their tests that their neighbors don't yet have. Perhaps this is true, and perhaps more people will send in cheek swabs to Oxford Ancestors or to Spencer Wells's Genographic Project if they think the not insubstantial money they are paying can tell them "where they come from", rather than one of the countless places. I repeat, every one of the thousands of test subjects that make up the data for the book descend not only from their assigned clans, but from all. Sykes acknowledges this when he writes that the Oisin clan was found in both Norway and Scotland, so that Oisin men from the Orkneys are not necessarily descended from Picts/Celts; he does this by wryly noting that the Vikings did not test their crew's Y-chromosomes. Advance this warning farther, and truly think about his subjects as individuals, and you start thinking about their fathers' mothers as well, their mothers' fathers, and every other line that passes through ancestors of more than one sex.
If Sykes's new view of British and Irish history exposes the poisonous notion of separate Saxon and Celtic peoples as a lie, a more nuanced view of genetic genealogical data can go even farther. Sykes tells human stories by bringing the individual line out of the data, a very important step, because it brings us away from very simplistic notions that would have peoples, not individuals, splitting off on the way out of Africa, perhaps never to reconcile. The next thing we need to do is put those individuals back into their societies by first putting them back into their families. Then, and only then, can genetic genealogy tell an accurate human story. It's one we all can, and need to, understand.
The U.S. title is Saxons, Vikings, and Celts, which is a strange change for a book which goes about proving that the migrations of Saxons, Vikings, and Celts aren't very significant contributors to British and Irish genotypes.
Yet it suffers from one important fallacy, the same that the most brilliant minds in genetics still make. Anyone who understands the numbers involved, and Sykes clearly does, is able to see that a male resident of Aran, let's say, of matrilineal clan Ursula (a woman who lived in Greece something like 45,000 years ago), and carrying the Y-chromosome of Somerled, the Gael who drove the Vikings from the Isles, does not just have these two as ancestral lines. In a population that includes hundreds or thousands of lineages (all populations) which does not limit marriage to within both patrilineal and matrilineal clans (no population I'm aware of), most lineages in the society will become ancestral to most individuals, given only a few generations. I have no doubt that Sykes understands this, but it's curious that he doesn't emphasis it. To me it is the *most* fascinating part of genetic genealogy. Genetic genealogy has the potetntial to forge a quick connection to both local and worldwide communities, not just a single or dual marker of heritage.
That man from Aran is not just descended from Ursula, but from all mitochondrial lineages surviving in his population and from many mitochondrial lineages now extinct, but which lasted long enough to be counted among his ancestors. The same is true of all current and all marginalized Y chromosome haplotypes. He carries his descent from Ursula and Somerled in his genes, true, and there's something very exciting about that, but it's his invisible lineages, traceable only through testing uncles or cousins, close and distant, that reveal his true nature as an individual who encompasses in his DNA the entire diversity of his society, both other common haplotypes and very rare ones. Traceable genes may not be in his mitochondria or Y chromosome, genes may not even have been inherited from these people at all, but his ancestry is far, far more complicated than a simple story that goes to the ends of the Mediterranean and then back to Africa. It all goes back to Africa, of course, but by 2lots routes, not 2.
I find it difficult to believe that Bryan Sykes has not thought this fallacy through. In Blood of the Isles, as throughout his popular work, Sykes strives to preserve the individual nature of data collected from his subjects' DNA, preferring to let stories, rather than statistics, emerge from the data. The first woman to carry a particular mDNA haplotype becomes a clan mother (his The Seven Daughters of Eve) instead of a number, and ubiquitous Y chromosome DNA lineages are traced, quite believably, to historical and mythological kings, warlords, and other such headmen. These are stories people can quite easily append to family histories that are much closer in time. Descent from Jasmine, the Syria-born matriarch of the Neolithic agricultural migrations into Europe, from Genghis Khan, or from Somerled, is a much more romantic notion than identity with R1B or O3 or H. It's certainly easier to talk about at the family reunion. Yet the essentially communal nature of genealogy brings in another question. Every nuclear family is made up of individuals of different matrilineal clan lineages, every extended family of many matrilineal and patrilineal ones. This is as easy a notion to understand as that a family can have many surnames. So why can't genetic genealogy explore it.
If I weren't confident that Sykes has science's best interests at heart, I would be cynical and say that he perhaps believes that Oxford Ancestors' coffers will be more easily filled if people feel they are getting a real sense of identity from their tests that their neighbors don't yet have. Perhaps this is true, and perhaps more people will send in cheek swabs to Oxford Ancestors or to Spencer Wells's Genographic Project if they think the not insubstantial money they are paying can tell them "where they come from", rather than one of the countless places. I repeat, every one of the thousands of test subjects that make up the data for the book descend not only from their assigned clans, but from all. Sykes acknowledges this when he writes that the Oisin clan was found in both Norway and Scotland, so that Oisin men from the Orkneys are not necessarily descended from Picts/Celts; he does this by wryly noting that the Vikings did not test their crew's Y-chromosomes. Advance this warning farther, and truly think about his subjects as individuals, and you start thinking about their fathers' mothers as well, their mothers' fathers, and every other line that passes through ancestors of more than one sex.
If Sykes's new view of British and Irish history exposes the poisonous notion of separate Saxon and Celtic peoples as a lie, a more nuanced view of genetic genealogical data can go even farther. Sykes tells human stories by bringing the individual line out of the data, a very important step, because it brings us away from very simplistic notions that would have peoples, not individuals, splitting off on the way out of Africa, perhaps never to reconcile. The next thing we need to do is put those individuals back into their societies by first putting them back into their families. Then, and only then, can genetic genealogy tell an accurate human story. It's one we all can, and need to, understand.
The U.S. title is Saxons, Vikings, and Celts, which is a strange change for a book which goes about proving that the migrations of Saxons, Vikings, and Celts aren't very significant contributors to British and Irish genotypes.
2007/01/05
Fortunately the Mayflower wasn't the only ship in the world
"A more homogenous stock cannot be seen, I think, in any so extensive a region, at any time, since that when the ark of Noah discharged its passengers on Mount Ararat, except in the few centuries elapsing before the confusion of Babel."
James Savage, et al. A Genealogical Dictionary of the First Settlers of New England (1860).
Silly Puritans, valuing this sort of thing.
James Savage, et al. A Genealogical Dictionary of the First Settlers of New England (1860).
Silly Puritans, valuing this sort of thing.
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