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99 of 102 people found the following review helpful:
4.0 out of 5 stars
Who are the British People?, March 6, 2007
In Saxons, Vikings, and Celts, Bryan Sykes, professor of genetics at Oxford, describes his research and conclusions on the Genetic Atlas of Britain project. His goal was to develop a description of how the genetic background of the current populations of England, Scotland, Wales, and Ireland differ from each other and how these differences might be traced to the various ethnic groups that settled the Isles: Celts, Picts, Romans, Saxons-Angles-Jutes, Vikings, Danes, and Normans.
Background: Because a person's nuclear DNA is derived from both parents in equal parts, trying to track one's genetic heritage backward is complicated by the doubling of the number of ancestors each generation. Even the most recent arrivals considered in Sykes' study, the Normans, ca. 1066, go back about 1000 years, or 40 generations. This gives us about 2-to-the-40th-power ancestors in that generation. That's a big number, roughly equal 10-to-the-12th-power, or about 100 times the current population of the entire Earth. This apparent conundrum reflects the fact that there must have been a large number of intermarriages among cousins of various degrees in the course of the 40 generations, so that many of the names on our lists of 10-to-the-12th-power ancestors would likely be repeated several times over. The message here is that the genetic heritage of a specific individual (his nuclear DNA) really can't be tracked back far enough to reach any useful conclusions about the population of the Isles in 1066 or earlier. However, all is not lost.
Methodology: To overcome this problem, Sykes uses two genetic markers that are passed on unchanged, except by rare genetic mutation. First, mitochondrial DNA (mDNA) is passed on to all offspring by their mother, unmodified by any contribution from the father. mDNA is not part of our genetic makeup that makes us individuals; it is located outside the cell nucleus and helps regulated metabolism in the cell. The rate of mDNA mutation very slow; about one mutation can be expected along each maternal line in 20,000 years. Second, the Y-chromosome is passed on from father to son, unmodified by any contribution from the mother. The rate of Y-chromosome mutation is about one change along each paternal line every 1500 years. Prior research by Sykes, and others, has shown that most people of northern European heritage belong to one of a small number of primary maternal lines and to one of an even smaller number of primary paternal lines. These lines are defined by the molecular patterns of their mDNA and Y-chromosomes. Furthermore, the mutation rates can be used to estimate the age of each primary line and the approximate times that subsequent mutations have occurred. Equipped with this knowledge, Sykes proceeded to collect DNA samples from a large number of current residents throughout the Isles, characterize the primary maternal and paternal lines, and examine any mutations to primary line patterns. He then compared the frequency with which primary lines occurred in different regions within the Isles and in locations which the migrating peoples came.
Conclusions: Sykes reaches several interesting conclusions:
1. Throughout the Isles, the basic and dominant genetic heritage is Celtic.
2. The basic Celtic heritage is modified by contributions from the other ethnic groups. The contribution from these groups varies from essentially zero up to a maximum of about 30%.
3. The Picts were closely related to the Celts, perhaps indistinguishable so.
4. The largest non-Celtic contribution is found in the northern islands, the Orkneys and Shetlands, where the Viking contribution is about 30%.
5. The Celtic settlers appear to have migrated from the northwest area of the Iberian peninsula.
6. The maternal and paternal lines often differ. The maternal line is often more Celtic, suggesting that women were less mobile than men (e.g., Viking raiders). The paternal lines suggest a disproportionate genetic contribution by a relatively small number of men (presumably those in powerful positions - the "Genghis Khan effect").
7. The maternal and paternal lines are fairly consistent in the Orkneys and Shetlands, suggesting that they were settled peacefully by Vikings who brought their wives with them.
Reviewer's Comments: Sykes' methodology of following the unbroken paternal and maternal lines allows him to work around the problem presented by the mixing of nuclear DNA (other than the Y-chromosome) at each generation. This approach essentially extracts a sample of one male and one female ancestor from each generation. Keep in mind that the number of ancestors is 10-to-the-12th-power ancestors 40 generations back and even more as you go back farther, so two ancestors is an exceedingly small sample of an individual's genetic heritage. Statistically, this is a valid approach when used to characterize the overall population because Sykes draws large samples from the current population. However, I caution against drawing any strong conclusions about one's personal genetic heritage based on that sample of two ancestors out of such a huge number.
The book is a nice, light read. Sykes spends the first part of the book on the pre-history of Britain, both the geological history and the stone age migrations which were shaped by the geological and climatic changes. After setting the stage, he focuses on the methodology and results of his research. The last third of the book focuses on the history and genetic characteristics of the four main regions: Ireland, Scotland, Wales, and England.
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30 of 31 people found the following review helpful:
3.0 out of 5 stars
Molecular anthropology, genetic archeology, March 25, 2007
Earlier reviewers sum up Professor Sykes arguments well. I read "Seven Daughters," and what struck me about this "sequel" is that Sykes does not engage in the imaginary narratives with which he enlivened the composite "life and times" of his seven genetic prototypical mDNA matriarchs. Those tales gave a poignant and charming (albeit popularized and therefore probably bound to annoy his colleagues) glimpse into the conjectured "inspired by a true story" that we cannot fully translate from Paleolithic Europe. "Saxons, Vikings, and Celts" avoids this fictional device.
Reading between the lines, as many readers and critics misunderstood his "seven daughters" as "real" individuals, Sykes may have opted for less creative methods to explain the patriarchal counterparts-- which are far more numerous if less attractively developed here in their genetically distinguishable progeny, it seems from their Y-chromosome variants. Instead you get potted histories and summarized geographies of the early formation of the land and the tribes that entered the various insular regions post-Ice Age. While valuable to a general readership who never heard of Geoffrey of Monmouth or learned where the Grampians sprawl, such data does fill these pages with a lot of material that veers tangentially from his genetic research. It's difficult in a book aimed at non-scholars to combine so much information from so many fields; it reminds me too of Jared Diamond's similarly ambitious, polymathic, and synthesizing efforts that roam widely in rounding up support for the grand scientific thesis that spans millennia. Like Diamond, Sykes arouses scholarly and popular controversy. He too likes a good anecdote, and labors to entertain as well as educate, and shows he can speak to audiences outside the learned seminar. We need academically trained authors who can fill this necessary role and so counter so much merciless jargon and dismal prose from their more timid, tenure-tracked, and dryasdust peers.
What puzzles me is the lack of any bibliography, any footnotes. Even popularized accounts usually provide references or suggestions for further reading. The work by Paul Besu into Scots emigrants' search for roots sounds intriguing from the quotes on pp. 53-4. But what's Besu's book, or article, titled? From where in his work are the quotes taken? There's nothing to go on here.
Sykes apologizes at one point for having to even mention "haplotypes." I was relieved he finally did; he builds on Prof. David Bradley and his Trinity College Dublin team's analyses of Irish DNA that were initially published about half-a-dozen years ago. When Bradley had announced this data initially, I had searched in vain for any layman's explanation of the study beyond a paragraph or two in the press. This book met my expectations for a summary of Bradley's team's work I could understand. Certainly, as on pp. 112-113, Sykes shines when he talks of the humanity behind the numbers to the thirteenth decimal point, and how the Isle of Skye's weather at his second home suits his scholarly pursuit. These moments of candor and passion sparkle amidst the recitals of the highest peaks in Scotland, evidence from Roman amphorae, and where to get the best ice-cream in Lampeter! It's as idiosyncratic as the studies of his lovingly- described forebear in research, John Beddoe, a century ago.
In "A United Kingdom, Maybe?" by Nicholas Wade, in the March 3, 2007, Science section of the New York Times, Stephen Oppenheimer's theory that most in the Isles descend from ancestors 16,000 years ago is also explained along with Sykes' somewhat variant interpretations. But Oppenheimer, also a geneticist at Oxford and so presumably just down the corridor from Sykes, is never mentioned in SV&G. Why? Professional rivalry? Reluctance to mention his colleague's work that would be explained in Oppenheimer's 2006 "The Origins of the British," that came out alongside Sykes' book? Silence seems strange, given both profs work on "British" DNA. Maybe it's academic etiquette or cautious reticence.
Oppenheimer agrees overall with Sykes that the Isles were settled by the group still genetically predominant today. Oppenheimer appears to claim a date significantly earlier than Sykes suggests here with "Cheddar Man," (whose tooth drilling by Sykes begins his book vividly) but the two are both arguing for a primarily "Celtic" (despite the problems with that psuedo-"racial" 19c term for a linguistic and not an ethnic identity common among certain earlier Europeans, as Sykes explains well) "bedrock" of shared ancestry for most of the Isles' present-day people. Sykes wanders these Isles before asserting this in his conclusion. Lots of his byways are fascinating, others depending on the reader's own predilections may be tedious, as on any journey with an eager if rambling guide.
Certain places of interest on the journey lack necessary details. While he cites Ireland's island-wide population at 5.7 million, how does the current situation in the Republic whose 10% of its residents are now foreign-born effect his estimations, which seem to assume all of the Irish population are of families at least a few centuries longer established? Similarly, I wondered how soon the genetic impacts of Italians, Poles, Jamaicans, Nigerians, or Chinese begin to alter the DNA composition in ways that can be measured in the peoples native to, but intermarrying with now, those arriving in recent decades as global immigrants into Great Britain. Did Sykes in his gathering of samples only test people who knew they had "native" origins? This selection is implied but not explained.
Also, he cites for a surname, e.g. "Dyson," (pg. 272) that 90% of those with the paternal surname share the same Y-chromosome from common ancestry. Does this confirm the rumor of supposed (10% of, some say, although this figure by others as been said to be inflated) offspring who are not paternally sired by their putative "fathers"-- or what of those adopted into a family, or in the old days fostered? Is there a "rate" measurable of non- "paterfamilial" births by women that shows a pattern over the centuries of a steady percentage of extra-marital pregnancies? Does this 10% explain the less than 100% chromosomal match to a surname assuming a paternal descendant's lineage? I am guessing these effects, but Sykes never tells us why there's this 10% discrepancy or its DNA cause.
More gaps remained after I read "S V & C." The "DNA of Wales" chapter seemed rushed. If Ealdgyth on pg. 227 was Queen of Wales before the death of Gruffudd, why did she have a Saxon name? More crucially, speaking of Welsh genetic roots, why the lower- than- expected rate of Y-chromosome "Oisin" mutations in mid-Wales? He mentions and maps in the back but does not give any in-depth detail about the "families" of the less common markers metaphorically named Eshu and Re. Where are these groups from? No help here. I don't understand how Wodan differs from Sigurd exactly.
Finally, he argues that women rarely move about as much as the men who invade and kill off their male enemies but spare their womenfolk as potential mothers. Where did all the males keeping alive the Y-chromosomes of the pre-Germanic Atlantic-Fringe, Celtic-speaking peoples retreat to and procreate undercover in the Isles? Is Sykes arguing that the maternal "native" stock is mostly "Celtic" and so this numerical preponderance outweighs the part-"Celtic," part-"Germanic, etc." male mix traceable in their Y-chromosomes? Or, is even the male side mostly majority "Celtic" even without the female indigenous element? I still am unsure.
If Gildas' claims of the "Ruin of Britain" were exaggerations, then how did these pre-Germanic cultures adapt to their new overlords, linguistically, while preserving their stubbornly "native" bloodlines genetically? More needed filling in here. Especially since on pg. 285 he notes the opposite claim, that Y-chromosome diversity in regards to dating its settlement dates has been challenged by claims to "patrilocality," men staying put while women wander off to marry. Sykes challenges this indirectly with the "Genghis effect," but I remain puzzled about this counter-claim of "men stay, women go" that opposes his book's conclusions.
But this uneven presentation manages still to end powerfully. He compares the mDNA to a smooth umbilical cord back into maternal mists, while the male Y "thrusts its way from generation to generation." (I add, in both senses of the word!) This maniacal patriarchal drive wreaks havoc, enslaves and kills in the name of conquest and destruction and empire. "We could not have any more different conduits into the depths of our ancestry." (pg. 279) I agree with reviewers who note that in our DNA quest we are only grasping two strands of a multi-colored thread, the only two whose twists we can follow, and that this obvious fact, strangely unacknowledged by Sykes, does threaten to become too reductive a trail to chart accurately our ancestral passage through the labyrinth of time.
As Sykes notes, the blur of Teutonic ancestries with the Vikings, Normans, Danelaw, Angles, Saxons, Jutes, and Roman legionnaires makes easy "tribal" genealogies difficult to unravel from the "Wodan" and "Sigurd" strands. This key point, undermining the manipulative historical claims by the English to an Anglo-Saxon, anti-Roman Teutonic, and therefore anti-Roman Catholic legacy of Germanic freedom fighters, finally explains why so many chronicles, legends, invasions, and conquests were "justified" by those who took over the name of the earlier British if apparently not their maternal inheritance to an ineradicable pre-Germanic, indigenous, eventually Celtic-speaking matriarchal heritage for the majority in today's Isles. Pg. 206: "The later arrivals may get...
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66 of 74 people found the following review helpful:
4.0 out of 5 stars
One in a million, December 12, 2006
This is a popular account of the Oxford Genetic Atlas Project, an attempt to map the genetic composition of Britain and Ireland. Prof. Sykes is something of an academic star, best known as the author of 'The Seven Daughters of Eve'.
The book is not heavy on technicalities but the necessary background is clearly explained. DNA is the instruction set for a living organism. Most of it gets mixed in sexual procreation, half coming from each parent. This does not happen, however, to two particular kinds: mitochondrial DNA (mDNA) which is copied from mother to children and is passed on only by daughters, and the DNA of the male Y-chromosome which is copied from father to sons. Because these come from only one parent, they remain stable over a great many generations. To cut to the chase, it is possible in principle to use mDNA to trace your matrilineal ancestry - mother, grandmother, great-grandmother - all the way back. Twenty thousand years ago there was just one living woman from whom you inherit your mDNA (maybe her mother was alive too - oh, all right, her granny as well).
By studying and comparing mutations in the mDNA sequence (random unimportant copying errors which, once they occur, are passed on) it is possible to allocate all human beings to a few dozen groups or 'clans'. Within each clan the lines of matrilineal ancestry are inferred to converge to one woman whom the author calls 'clan mother'. For example, most people of west European origin are descended from one or other of seven clan mothers who lived between 10000 and 45000 years ago. Prof. Sykes believes he can determine where as well as when these clan mothers lived: 'Helena' in the south of France, 'Jasmine' in Syria and so on. I am no geneticist and there are assumptions here that I am not qualified to comment on.
Half the book is taken up with thumbnail sketches of the countries of the Isles - England, Ireland, Scotland, Wales - with the focus on early history and prehistory. Depending how much you know about the Isles and how much you want to know, you may find this interesting. In each case the author describes how he collected DNA samples. To tell the truth, some readers have been known to take against the Prof's style ('I did this, I did that') but it flows well and it grows on you. He sorts the data into clans and plots them on maps of the Isles by reference to the birthplace of the donor's maternal grandmother. What we have at this stage looks, to the untrained eye, like a set of maps called Helena, Jasmine etc. with measles.
In a later chapter he summarizes his conclusions, which are briefly as follows. The genetic bedrock of the Isles was laid down by hunter-gatherers who moved in after the last Ice Age, followed by farming folk coming from Spain several millennia later. The most paradoxical not to say disappointing result for some readers will be that he finds no genetic affinity between the Celtic fringe (Wales, Ireland, Gaelic Scotland) and the Iron Age Celts of continental Europe. The 'Celts' of the Isles talked the talk, but that seems to have been as far as it went. He does find a significant Norse overlay in the Northern Isles of Scotland, and a less pronounced north German/Danish input in parts of England. Another genetic archaeologist recently claimed that the majority of English people - contrary to orthodoxy since the Second World War, for obvious reasons - are descended from incoming Anglo-Saxons. It all depends on interpretation, and I have a feeling that a lot remains to be thrashed out. Invasions might not come in waves but academic fashions do.
Now let me mention a thought that gives me pause. Going back 500 years I have up to a million ancestors (fewer in fact because of inbreeding, but still a lot). Just one of them was a matrilineal ancestress from whom I get my mDNA, and one was a patrilineal ancestor from whom I get my Y-chromosomes. If you're a WASP, one or both of them could be yours too. Prof. Sykes likes to make up imaginary scenarios for his clansfolk, so here goes: my matrilineal ancestress was a runaway Spanish nun, and my patrilineal ancestor was the Genoese sailor Giacomo, a big-time bigamist. Reconstructing early Tudor England from those two would be quite a trick. Now go back twenty thousand years. I have one clan mother and one clan father. This does not mean that I had no other ancestors living then (still less, as one poor soul thinks, that it proves creationism), merely that I happen to get my mDNA and Y-chromosomes from those two out of many contemporary ancestors. This is a perilously small sample - two out of how many thousands? - but perhaps it can tell us something reliable about prehistory. Is that obvious? I don't know, and you won't find the question raised in this book.
I don't believe the book is the last word; it could even be misleading if, for example, people think they come from Syria because their clan mother is Jasmine; but it is well written, interesting and worth reading.
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