on April 1, 2004
Sykes has done it again with this follow-up of his "Seven Daughters of Eve." "Adam's Curse" is a terrific survey of the latest findings on human genetics as told through the Y chromosome, inherited exclusively through one's father. There are plenty of new ideas here, coupled with a rather informative short course on the twentieth century's additions to Darwin's theory of evolution.
This is not a dry recitation of the facts, by any means. It contains his personal story of unraveling some of these puzzles himself, told in an a lively and amusing manner, sure to hold the reader's interest. There are history lessons, such as the one about the lamentable foul-ups of the microscopists trying to count the chromosomes. And Sykes tale of observing his own Y chromosome, carrying out the manipulations with his own hands, is described in some detail. There are stories about his coworkers, including the giant William Hamilton, who probably is second only to Darwin in developing the theory of evolution. But mostly it is the story of the application of modern genetics to the varied populations of the world, the story of their migrations and conquests, and the struggle of the Y chromosome to survive.
Sykes' distinct approach is to apply some relatively simple molecular probes to Y chromosomes obtained from many individuals in a variety of populations on a fairly big scale, rather than the other important task, carried on by a myriad of scientists, of trying to understand all the biological minutiae of a single prototypical human.
His finding the Y chromosome inherited today by about 500,000 descendants of the founder of the MacDonald, MacDougalls and the MacAlisters Clans is quite fun to read, and the similar tale of his discovering the Sykes clan reveals something about how curiosity driven science can be so deeply satisfying. The stories of the Vikings, the Polynesians, the Great Khan, and conquest by the Spaniards in South America are all covered here and the new insights revealed by their Y chromosomes gives a tantalizing glimpse of those still to come from other parts of the world. I can't wait.
Probably most unusual for a book of this sort, is that Sykes, a distinguished scientist, lays on some pretty far out, half-baked, probably wrong, but testable ideas about such things as the origin of homosexuality, the war between the sexes from the perspective of the Y and mitochondrial chromosomes, and even the possible future course of the evolution of the Y to its ultimate demise. This is a refreshing contrast to the plodding certainties of the refereed publications of the academics, hedged about with all the required caveats and cautions. In spite of his sometimes over-anthropomorphized chromosomes, this is an entertaining read, rewarding to readers yearning to understand the human beast.
on September 6, 2004
Unlike the other Amazon reviewers of the book, I am not an outside observer ... I'm actually in the book, as I'm one of the "Somerled people" he has a whole chapter about. That is, I share the same DNA as the MacDonalds he tested and claimed were descended from Somerled, a Viking who was the hero of the Gaelic northern Scots.
This is a wonderful chapter, well written and compelling ... especially for me! It's also quite correct. Unfortunately Prof. Sykes won't share his DNA results with other researchers, genealogists, and the general Clan Donald membership, so a new study was set up by the Clan Donald, and I am privy to their actual numbers. They are rock solid proof.
Seeing the actual numbers .... the Clan Donald study has published the most likely actual DNA marker numbers for Somerled ... leads farther back. Sykes's next chapter after MacDonald is about Genghis Khan, who hailed from central Asia. Interestingly, and this is where secrecy can be counterproductive, someone noticed that Somerled numbers, as well as lots of Icelanders' ones, showed a close affinity for men in a certain central Asian tribe. Time will tell whether the Vikings themselves came from central Asia. Stay tuned.
I found most of the book, not just my own chapter, quite entertaining, except for the part that makes up the title. It is simply baloney. As others have reviewed, Sykes has a good popular style and gets across a goodly dose of the science of DNA to the non-genealogist layman. It's just the disastrously stupid idea that human men will disappear ... it's odd he does not note that the exact same argument applies to all mammals .... and they've been around a LONG time ... that ruins this book. I need not say much more, as others have pilloried Sykes sufficiently for his transgressions.
on July 30, 2004
Perhaps it's my ignorance of genetics. Or possibly it's the vertigo-inducing thought that there's a whole set of cellular actors with agendas of their own out there manipulating human behavior. But, for whatever reason, Bryan Sykes' book, "Adam's Curse: A Future Without Men," made my head spin.
Is Sykes' main point in "Adam's Curse": 1) that the Y chromosome is dying out and thank goodness it is, because if not it would eventually destroy us all? 2) that the Y chromosome is dying out and actually that's a bad thing which we'd better do something to stop? 3) that the Y chromosome is neither better nor worse than the X chromosome, each one fighting to replicate itself down the generations (alternative book title suggestion: "Chromosomes Gone Wild: The Battle of the Sexes Goes Cellular!")? 4) that the Y chromosome is truly and veritably a "curse," guiding the Vikings, the Genghis Khans of the world, and men in general to rape, pillage, and burn their way through history? 5) that the species -- and the planet, for that matter -- would be better off if men were completely eliminated and women reproduced with each other? 6) that male-female sexual reproduction is inherently a bad thing? 7) that we we are all just puppets of our chromosomes and DNA, which are using us to their own ends? 8) that all these issues are to be looked at objectively and dispassionately as a scientist? 9) alternatively, that these issues should be considered subjectively and emotionally by a human being with a particular set of beliefs regarding civilization? Ouch, my head hurts!
Whatever the answers to the questions posed above, in my opinion "Adam's Curse" is well worth reading as a fascinating and important, if strange and disturbing, book. Bryan Sykes is certainly a serious scientist (professor of genetics at Oxford University), so his findings and musings -- strange and even outrageous as they appear -- can't be so easily dismissed. Sykes has done a great deal of research, no question about it, and he lays that research out here in a readable, direct, and engaging -- if sometimes rambling -- way.
One caveat: I suspect that to judge whether Sykes is on the right track or not, it would help to know a lot more about the latest developments in genetic science than someone like myself. Still, Sykes is a fine storyteller, and one of the rare scientists -- Carl Sagan and Stephen Jay Gould spring to mind - who can actually explain things in a readable way to non-specialists. The bottom line? If you're interested in the dramatic, fascinating "war between the sexes" at its most fundamental, genetic level, then this is a book you ought to consider reading.
on August 1, 2005
In his earlier book, The Seven Daughters of Eve, Bryan Sykes described how mitochondrial DNA, passed only through the female line, reveals the descent of different populations from ancestral women. Here he turns to the other side of the coin: Y chromosomes, passed only through the male line, reveal descent from ancestral men. Surnames, at least in the system used traditionally in the English-speaking world, behave in the same way, being passed to children by their fathers, but not by their mothers. So does the information deduced from Y chromosomes agree with that implied by surnames? Do all of the people called Sykes, for example, descend from a particular man who adopted this surname in the 13th century when surnames started to be used systematically in England? There are at least two reasons why the answer might turn out to be no: numerous different unrelated men might have adopted the same name independently, leaving numerous different unrelated groups of descendants; or perhaps over several centuries sufficient sufficient women may have had sons by men other than their husbands to have eradicated the evidence. It turned out that about half of the men in England with the names Sykes today have the same (or almost the same) Y chromosome, a surprisingly high proportion that implies about 99% fidelity of transmission in each generation.
Sykes assures us that his figure of 1.3% "non-paternity events" (births of children whose biological and legal fathers are different) is a maximum, but he is forgetting a simple and plausible mechanism that would allow a much higher frequency. In past centuries married women suffered great social pressure to produce children, but what could a fertile woman married to a sterile man do to satisfy her parents-in-law? By far the least risky thing to do, even before anyone knew about Y chromosomes, would be to have a child by a brother-in-law. Such a "non-paternity event" would preserve the appearances, would keep everything within the family, and would be more likely to be tolerated and even approved of by the husband and his family than any other solution.
Much of the detailed information is fascinating, and the book is easy and enjoyable to read. It has some major faults, however, especially in the second half, where much of the discussion is muddled, speculative and at times dishonest. Some scientists avoid statistical arguments, preferring to base their conclusions on experimental results so overwhelmingly clear that statistical analysis is hardly necessary. This can be wasteful, but it is intellectually defensible and is adopted by some entirely respectable scientists. Bryan Sykes wants to have his cake and eat it, however, using statistical calculations when they suit the conclusions that he wants to draw, and dismissing them when they don't; that is not intellectually defensible. Having satisfied himself that the frequency of his own Y chromosome had increased 10000-fold since the 13th century, despite his belief that "the Sykeses were never wealthy or powerful" (forgetting, perhaps, that three Sykes baronetcies, two dating from the 18th century, do not suggest a family on the edge of poverty), he wonders about the reasons for its success. Rejecting, for no clear reason, the common-sense explanation that even without any selection some genes become fixed and others become extinct, he studies school registers in search of evidence that Sykeses have tended to have more sons than daughters, finding that 212 out of 393 Sykes children were boys. He calculates that a proportion of sons as high this was likely to occur "just under 6 percent" just by chance. (The correct answer is about 6.5%, but let that pass.) He neglects to inform his readers, most of whom cannot be expected to be knowledgeable about statistical conventions, that this would have been reported as "not significant" in any serious analysis ever since modern statistical tests were introduced in the 1920s.
Worse is to come, however. Finding a family with 23 girls and 4 boys he estimates the probability of this occurring by chance as 1 in 5000, which he describes as "very long odds indeed", even though he knows perfectly well that the calculation assumes a randomly chosen family, whereas he has carefully selected a specific family in the expectation of an extreme result. What is dishonest about this is that Sykes knows, and occasionally mentions, the reasons why his calculations are illiegitimate, but he hopes his readers will be fooled anyway. Eventually, coming to arguments that supposed evidence for a gene for homosexuality were unfounded, he refers contemptuously to people who think that statistical arguments should be used properly as "the guardians of statistical integrity" and tells us that in his experience they are usually wrong.
Several chapters in the middle of the book set out the ideas of sociobiology, but it is not obvious why these were included, as they add little to the rest of the book, and nothing to the far more expert accounts that can be found elsewhere, in the writings of Richard Dawkins, Mark Ridley, Matt Ridley, and others. At least we are spared, however, the seven chapters of romantic fiction that came close to ruining The Seven Daughters of Eve, and the purple passages dealing with Gaia are mercifully short.
The subtitle of the book promises a "future without men", and the blurb assures us that "men are slowly, but surely, headed for extinction". For most of the book this seems to be little more than advertising hype, and the evidence, when it eventually comes is thin and speculative. It is also confusing and muddled, because although some problems may be specifically human - maintaining the testicles too warm, excessive exposure to mutagens, etc. - the main theme that Sykes develops is of a fight to the death between the man-hating mitochondria and the women-hating Y chromosomes, which, he thinks, will eventually be won by the mitochondria. However, if this fight is going on it must affect not just people but all of the great array of other animals that determine sex in the same way, including virtually all mammals.
30 or 40 years ago popular books about the human species, such as those of Robert Ardrey or Desmond Morris, tended to stress Man the Mighty Hunter, with an obsession that Elaine Morgan rightly ridiculed as the Tarzan school of biological thinking. Fashions change, however, and if one may judge from this book and Steve Jones's recent "Y: the Descent of Men" the current vogue is for books about Man the Pathetic Wimp, with Y chromosomes in bad shape, a "graveyard of rotting genes", and sperms of low and diminishing mobility, unlike those of our cousins the chimpanzees, 100% of whose sperms are "in excellent shape". No doubt this explains the success of chimpanzees in spreading themselves over the entire earth and restricting humans to tiny relics of their original range; but maybe I have missed a key step in the argument somewhere.
on October 22, 2005
I enjoyed this book but did find it a bit more challenging to read than Seven Daughters. Seven Daughters dealt with his research into the inheritance of mitochondrial DNA which does not combine and has a fairly straight forward lineage. In Adam's Curse, he is trying to track the Y. Even though the Y itself does not combine, everything around it does and he explains how this works in great detail. This becomes important later on as he draws his conclusions about the peril of the Y and the "important" part of it, the Sex Determining Region on the Y or SDY. Not having a background in the field, I really had to dig in and understand what he was saying to get his points but I am glad that I did.
What he puts forth - that we should look at this from the view point of the X and Y genes and that they have conlicting agendas (and murderous intent against each other)- at first sounded ridiculous but his theories on the attempts and abilities of certain mitochondrial genes to abort or effeminate male conceptions began to sound really interesting. When he applies the outlook to male behavior in general it seems crystal. I have seen a lot of reviewers really slam this book for its views. While I do not have the education to respond to the probability of whether he is correct or not, I am interested in what becomes of his theories.
on March 23, 2004
Elements of this book are quite interesting but you have to wade through an awful lot of waffle to find them. Bryan Sykes belongs to a growing number of scientists who think that we are as interested in them as we are in their science. Sykes' work in human genetics is truly fascinating but is hidden beneath endless descriptions of his own family tree, the architecture of the buildings he works in, his train rides, his musings as he stares out of his office window, and an inexhaustible number of other tediums that his publisher should have edited out. Had they done this, however, the book would have been a quarter of its present length.
Theoretically, the main subject of the book is the interplay between the DNA that is exclusively owned by men (the Y chromosome) and that which is exclusively owned by women (mitochondria). The subject is not new and is dealt with much more effectively elsewhere (for example, Sex Wars by Michael Majerus or Y: The Decent of Man by Steve Jones). The subtitle of Sykes' book - A future without men - is misleading as the supposed demise of the Y chromosome is only referred to at the end of the book. It is typical of the media friendly sound bites that Sykes litters his book with.
Male homosexuality is another case in point. The subject has become very popular amongst scientists in recent years and some excellent work has been published (Roughgarden, Muscarella, Kirkpatrick). This has only been achieved as (most) scientists have learnt from past mistakes and treated the subject with awareness and sensitivity. Sykes bludgeons in on the act like a bull in a china shop. Male homosexuals are to be explained, Sykes declares, by a mother's failed attempt to destroy male foetuses in utero. This "poisoned kiss" happens as a result of a genetic battle between the Y chromosome and mitochondria. A mother, according to Sykes, performs this 'semi-abortion' to provide additional child-rearing helpers (just as "sterile workers in the hive were doing for their queen bee").
New sound bite; old (and disproved) idea. Homosexuals are not sterile and worker bees are not homosexual. There is not a shred of evidence to support the idea that women are attempting to abort foetuses that eventually become homosexual men. Moreover, there is very little zoological or anthropological evidence to suggest that homosexual offspring act as `helpers' to their mothers any more than heterosexual offspring do (zoologist Bruce Bagemihl laid that one to rest in his excellent 1999 book Biological Exuberance: Animal Homosexuality and Natural Diversity). These are all tired old chestnuts from last century (not, as Sykes would have us believe, his "own rapidly forming theory"). Both author and publisher should know better.
Big ego, little science - this I can just about stand because it is inconsequential. The consistent references to various diseases in Sykes' 'gay genes' chapter, I cannot. Achondroplasia, sickle cell anaemia, coronary heart disease, diabetes, schizophrenia, manic depression, bipolar disorder, haemophilia, colour-blindness, cystic fibrosis, haemochromatosis and Black Death (BLACK DEATH!) are all used to varying degrees to postulate on how gay genes might benefit heterosexuals and therefore get passed through the generations. Homosexuality is guilty by association in the first page of this chapter - "I have worked on inherited diseases for a good part of my scientific career and there is no denying that homosexuality has some of the genetic characteristics that you might find in a serious inherited disease." The disclaimer that follows is pretentious and insulting.
It was precisely this kind of unsupported association between disease and homosexuality (frequently made by blinkered scientists) that political and religious fundamentalists leapt on in defence of their extreme homophobia when AIDS broke out in the 1980s ("When it comes to preventing AIDS, don't medicine and morality teach the same lessons?" Ronald Reagan, 2 April 1987). Western governments absorbed these ideas and we now live with the devastating consequences of their muted response to the AIDS epidemic. The catastrophic and continued association between sexuality and disease is chartered in a brilliant book called The Wages of Sin: Sex and Disease, Past and Present by Peter Lewis Allen. Sykes obviously hasn't read it but he should before passing further judgment, albeit obliquely, on a section of society that he clearly knows little about.
on December 8, 2004
I greatly enjoyed The Seven Daughters of Eve, and Adam's Curse had some memorable moments as well. But in the latter, I wondered how such a competent scientist could stray so far from science. Bryan Sykes is a marvelous story teller and I enjoy his train rides and personal anecdotes. I read such books as much for enjoyment as for knowledge. But in this book he seems to be making suppositions that are not backed by anything close to fact. By the time I got to chapter twenty-one, I was wondering what kind of mushrooms Bryan had been eating. Still, I will buy his next book. Adam's Curse was at least thought provoking.
It is a well written and engaging book, perhaps not as much as the first book, but, nonetheless, enjoyable to read.
If one reads the book carefully it is fantastic. Pay attention when he talks about the pallendromic nature of the Y Chromosome, which does lend it some capacity to fix itself, and pay attention to the actual timeframe of the supposed collapse (distant future if at all).
The danger is not imminent, if it is present at all.
The more interesting part of the book is the fact that the Y-Chromosome can be and is used to trace the genetic history of men. This, coupled with mitochondria, composes the whole of the largely non-recombining genetic world of humanity and provides it with an ability to communicate information that is lost when genes recombine.
However, even this is taken too far at times. For instance, Sykes is unjustified in arguing that because no Neanderthal mitochondria and Y-Chromosomes can be found in modern humans, this means that there were no Neanderthal progenitors of modern humans. Indeed, if only seven mitochondrial groups survived to modernity in Europe, this is a stark indicator of just how rare it is for an individual woman's mitochondria to survive to the present.
This should come as no shock since Y-Chromosomes and Mitochondria are largely selectively neutral. The genetic markers that we should expect to survive that long (if there were only limited inter-breeding between the two species) would be the genetic markers that accompany traits that are positively selected. Some of these have been found. Indeed, with the proposed introduction date of microcephalin being just 35,000 years ago, this might just fit the ticket. Other posibilities could be whiteness, red hair, or any number of other items that would have helped African humans survive in Europe and the Middle-East.
In short, I largely agree with Dr. Sykes. What is more, he is a compelling and engaging read. However, I think that he has a tendancy to be a bit dramatic and to make just a little bit too much out of two solitary genes.
on May 24, 2004
For all Syke's research ability his political bent blinds him to wisdom.
What Sykes hypes as a "war between the chromosomes" could just as easily be seen as a "co-evolving of the chromosomes". In another view the X chromosome, with its low duplication rate (vastly fewer ova produced in a females lifespan relative to sperm in a male), and the manner of ova protection deep within the female body makes the X chromosome much less exposed to selectional forces. This makes the X chromosome the "preservational" half of our nature. Contrast this with the Y chromosome, which is produced in vast numbers to encourage copy "errors" (I prefer "selectional options"), exposed to higher levels of mutagens from the environment, obliged to prove fitness by finding the ova prior to conception, which gives us the "selectional" half of our nature.
The X chromosome "system", being highly resistant to mutagenic forces, could not have survived long enough to evolve, nor will it be able to continue surviving for long, without partnership with a more selection-exposed partner.
Our mitochondria will always have a more selection-exposed partner, it may not be Y-shaped, but it will be there. What Sykes labels as "useless" sections of DNA in the Y chromosome aren't there in response to an existing need, they are there in case a need for them arises, so that selectional forces can operate on them. I would not find it surprising if future scientists find a mechanism whereby highly proven genes in the "selection exposed" Y chromosome become dupicated (and more protected) in the "preservational" X.
I could go into the vast cross-cultural sociological evidence of how the X/Y systems influence the phenotypical gender behavior of entire societies so that females are statistally more and males statistically less risk averse, thus creating another level on which the Y chromosome is more exposed to selectional forces (i.e. REALITY).
Sykes comes off, with all his musings, as the grand epitome of the dominated self-hating male. He is actually a great researcher, but a lackluster sythesizer of what he discovers. His view of the Y chromosome reminds me of leftist politics, with its ideas of creating a risk-free and "level" environment for all, is based, whether it realizes it or not, on fantastic ideas that we do not need to be exposed to reality, only to ourselves.
"Infotainment" is annoying enough, but "infotainment with an agenda" is just plain cloying.
on June 24, 2004
Mr. Sykes needs to read a small work known as "The Origin of Species" by a Mr. Charles Robert Darwin. Disregarding the post-publication discoveries of mitochondrial DNA's ability to undergo recombination with the Y chromosome and the fact that Y chromosome is capable of some sophisticated self-repair (unlike other chromosomes). Sykes has sadly, started with some false assumptions and jumps to some poor conclusions.
He says: "Originally the Y-chromosome was a perfectly respectable chromosome [sic] but its fate was sealed when it took on the mantle of creating males. This probably happened in the early ancestors of mammals, perhaps 100m years ago when a mutation on the ancestor of the Y-chromosome suddenly, and quite by chance, enabled it to switch on the embryonic pathway to male development." This is a false assumption, the chromosome didn't become enabled "quite by chance" on a organism/populational scale. This trait was, according to theory, selected for the advantages it conferred on the species. In accordance with this theory, the ticking time-bomb type of number that Sykes gives as 125K years seems whimsical, especially, given the approximate age of homo sapiens of 250K years. First off, I don't beleive for a second that given the rate of information tech and biotech advancement that anyone can make any predictions more than about 100-200 yrs. in advance. Clearly, we males won't all lose function at the same rate and end at the magical 1% fertility at 125K years. Intrinsically, those who are less fertile won't reproduce as prolifically as those who, for any number of reasons (some of which are already being uncovered), maintain functionality.
Interestingly, Sykes cites only one other species who is/has this problem, the vole. This is astonishing for two reasons: 1)Lots of other sexed animals turnover much faster/slower than us reproductively speaking, which would accelerate/decelerate their demise. 2) Lots of other sexed animals developed their sex much earlier/later than us, which would make their extinction much sooner/later than ours. Given the possible spread of species extinction, it's hard to believe that we're the only species with an impending doom in the next 125K years. Additionally, the vole's sex determination is nothing like our own and is arguably not comparable.
Finally, Sykes suggests that a solution to the problem is to do away with men using some form of embryonic fusion for reproduction and he merely passes it off as that simple. Once again, Sykes needs to read up on his most fundamental of genetics. Bacteria permeate virtually every environment on the planet. They reproduce quickly and mutate easily. These two facts allow them to explore lots of adaptations quickly. Without mutation, bacteria (and other non-sentient organisms) couldn't adapt. So, some degree of mutation is required in order to cope with a changing world. Now, if you fuse two eggs, you inherently lose the 'hypermutability' of the y chromosome, thus making the species arguably less adaptable (think of all the times you've heard that women find stronger, more-rugged men more attractive because they seem better able to survive). In addition, you also homogenize the human race. So, much more pressing and as yet uncurable, diseases like cervical/ovarian/breast cancer, TSS, depression, and other women-biased diseases become a species-endangering threat. Not to mention that you're talking about the systematic sterilization/elimination of half the world's current population (statistically speaking, the bigger, and stronger half).
Given the obvious bias Sykes has against males and the huge gaps in his theory (just with Darwin's theory alone). It's hard to believe he either a)doesn't have a financially or politically motivated agenda or b)isn't just a skewed, bombastic eccentric. Either way, his assertions don't pass the muster of theories laid down over one hundred years ago. To hold this work up as great scientific work would be a lark. His theories are bad even for science-fiction. I was going to give Sykes two stars for his engaging writing ability but then I remembered he's the head of human genetics at Oxford, so his writing should be good and being the head he should have a more sound theory. One star.