[.uk] The Cooperative Gene: How Mendel's Demon Explains the ... (ISBN 0743201612)

Amazon.com Review:
The Cooperative Gene is about sex and how sex enabled complex life to arise. Mark Ridley, a researcher and author of many works including the textbook Evolution, contends that simple life is "easy." Simple life like bacteria evolved as soon as conditions on Earth permitted. But complex life--walking, flying, swimming, squawking organisms with differentiated tissues--was a huge step forward. It took billions of years for complex life (and sex) to appear. More than anything, organisms want to pass on their genes. Sex seems to defy natural selection in its ability to convince organisms to pass on only half their genes. Natural selection will favor "selfish" genes, ones that can beat the odds and get passed on. But if this happened all the time, complex life could not exist. So how does it? Enter what Ridley describes as "Mendel's demon," a system in which genes are passed on in a random fashion. Most important, the demon prevents selfish genes from sabotaging that randomness. Although Gene isn't a technical book, its ideas are complicated. Ridley's style is methodical, broken by the occasional dryly humorous aside. Evolutionary biologists and other assorted PhDs will no doubt be entertained. Popular-science buffs may find it slow going, but they will be rewarded by a thorough understanding of the topic. In his last two chapters, Ridley leaps further afield, exploring the influence of technology on human evolution and speculating how future science could change us. He also examines the idea of supercomplex organisms, beings that would tower over humans in complexity to the same degree that humans tower over bacteria. It's pure speculation but compelling nonetheless, worthy of its own book. --J. B. Peck

Fascinating Premise; Witty Writing; Vague Explanations:
I don't know if Mark and Matt Ridley are brothers, but they should be. Each is English, has a doctorate, and writes in an engaging and literate way about evolution. Matt seems more interested in what is called "evolutionary psychology", discussing social issues in the light of our evolved traits. Mark is more the scientist, pursuing the fundamental questions of life. This book is about such a question: why did complex life evolve at all? At first that might not seem like much of a question. The hard part, after all, is to get "simple" life -- a bacterium. After that, given enough time and the creative power of DNA mutations, complex life is more or less inevitable. Right? Actually, from the evidence it seems that simple cellular life evolved rather quickly -- within a few hundred million years at most -- after it was possible for any life -- that is, after the planet had cooled down and water was mostly liquid. Yet, after that it may have taken two billion years for the eukaryotic cell to arise. That is such a large part of the total amount of time life has been on the planet that it is very possible that the eukaryotic cell might never evolve at all if the history of life were rerun. And, according to Mark Ridley complex life -- multicellular life -- only arose because the genetic mechanisms invented by the eukaryotic cell allowed it. Complex life is complex because it has lots of parts, and requires lots of DNA, which must be duplicated from generation to generation. Copying errors turn out to be a limiting factor once you get to billions and billions of "letters" in your genome, even with the various enzymatic mechanisms for checking and correcting DNA copies (invented by bacteria billions of years ago and never improved upon). For bacteria, 99% of their offspring are perfect genetically, since their DNA is short enough that errors are unlikely. For us, we're lucky to get one or two perfect gametes in a hundred. So how in the world can we go on, generation after generation without degrading like a much-xeroxed document? In a word, sex. This is really the crux and subject of the book: sex, gender, and the peculiarities of meiosis are there to overcome the daunting problem of copying error and allow beings with lots more DNA than a bacterium to quite faithfully reproduce themselves generation after generation. Even without any steamy scenes sex and gender are fascinating, and Ridley's explanation of why we have them (sex and gender are not the same thing) is convincing and entertaining. But I will say no more about that. You will just have to read the book, which I recommend, with some reservations. I like Mark Ridley's writing. His sentences are graceful and laced with wit and learning. Where he falls down, though, is in the explanations, or justifications, for the material he introduces. The ideas of copying error and how it plays out in different organisms was new to me, as were the arguments justifying sex, gender, and the peculiarities of meiosis. On the way to them there were also various subsidiary conclusions, and in few cases were his explanations terribly coherent. At least part of this book had its genesis in lectures, and it shows. There are small inconsistencies: he refers to the new result of 30,000 genes in a human, for example, and later casually throws in the older presumption of 100,000, no doubt in a section lifted from an earlier talk and never corrected. But more annoyingly, his basic style of argument is what an old math professor of mine called "hand-waving". This is where you talk fast and plausably to skate over difficult points rather than using logic. Lectures to a lay audience tend to be mostly gee-whiz facts, jokes, and hand-waving arguments. Ridley is not that casual here, but still induced a kind of mental whiplash by discussing in excessive detail rather obvious points, and then making a sudden jump across an intellectual chasm to a daring conclusion, then blandly continuing. In conclusion, I would recommend the book for its very interesting subject matter and breezy style. But I would add that you might find yourself wishing for a bit more rigor. Or not.

The Cooperative Gene:
The Cooperative Gene: How Mendel's Demon Explains the Evolution of Complex Beings written by Mark Ridley who is one of today's leading evolutionary thinkers. This is a well-written book that brings to the reader an intellectual treat. "The Cooperative Gene" give us clues as to why and how complex life came about. It was by natural selection by ingenious solutions to copying errors and uncooperative genes. The author explains everything in a distinctive style that is very cleve... indeed. This book is geerd to a person with a scientic background as it delves into biology, biochemistry, and cell biology, but it isn't out of reach of a well read lay person. The author's wit and intelligence comes through and he seems to get the reader involved so you're not lost. I was pleasantly intrigued by the author's historical grounding of this book and the up to date relevance. From the initial wobbly, replicating molecules, through microbes, worms and flies till we get to mankind, the author reveals how life evolved on earth. Natural selection encouragess genes that look out for themselves, while delfish genes that could easily evolve to sabotage the development of complex life forms. Ther author painstakenly explains the difference between a selfish and a cooperative gene. As well as giving the reader his definition of Gregor Mendel's fundamental laws of inheritance... Mendel's Demon, thus, we find out about the origins of sex, gender, and cloning. The DNA in a human being is 6600 Million letters long and codes for about thirty thousand genes. In contrast, the DNA of a bacterium is two or three million letters long and codes for two or three thousand genes. You see where coding for a human being can bring on more mistakes. Mendelian inheritance controls how genes are inherited in complex life. It combines sex, reproduction, and the probabilistic rather than certain inheritance of genes. All in all, this book was rather captivating to me, the narrative wasn't overbearing and it easily readable, but you have to have a scientific origin to get the most out this book.

Law enforcement in reproduction:
Mark Ridley has two major themes in this book, the appearance of what he calls complexity, and the role of what he calls gender. I use this awkward repetition of words because what Ridley calls complexity is not what students of complexity call complexity, and what he calls gender is not what linguists call gender. Unfortunately he is not very precise with his definitions in either case. Indeed, in the case of complexity he recognizes his vagueness explicitly: "Complexity is an ill-defined term ... I am as puzzled as anyone by what exactly I mean when I say it." One may hope for something a bit clearer than that, but one will be disappointed. Most of the time what he seems to mean by claiming that humans are complex and bacteria are not is that a human is an organism with numerous kinds of cell, most of which have nuclei, whereas a bacterium is just a single cell with no nucleus. It is reasonable to ask what conditions allowed multi-cellular nucleated organisms to appear, but less reasonable to claim that bacteria are not complex. The other term that is crucial for the book, but is ill-defined, is gender. Ridley uses it to distinguish sex -- the idea that an individual is the result of mixing the genetic information from two different parents -- from the idea that the two parents are different from one another, coming from two (or more) classes such that the members of the same class cannot breed with one another. Unfortunately he not only neglects to explain in so many words that this is what he means by gender, he also forgets from time to time to maintain the distinction, referring, for example, to "single-sex changing rooms" when he means, in his terms, single-gender changing rooms. To this point I have concentrated on the more negative aspects of the book, probably excessively, because there is a large amount of interesting discussion in it as well. Ridley has a lot to say about the dangers of conflict between the different genetic components of a multi-cellular organism: conflict between nuclear and mitochondrial genes, between nuclear genes from the two different parents, between the mitochondria from different parents, and so on. He argues that avoiding and defusing potentially disastrous effects of such conflicts explains what would otherwise seem absurdly complicated and wasteful ways of doing things. Most organisms exclude the mitochondria of one parent from entering the egg when it is fertilized, but the few exceptions illustrate what can happen if they are not excluded. In mice, for example, the paternal mitochondria do enter the egg, "like missionaries walking into a cannibal feast", whereupon they are promptly destroyed. Even in humans some paternal mitochondria are able to escape the strip search of the sperm cell when it enters the egg, but they too are destroyed. Yet mitochondria are expensive to produce, and potentially valuable, so why wantonly waste them? Avoiding even more wasteful wars with the maternal mitochondra appears to be the reason. Ridley explains that most of the apparent complications in reproduction are necessary for effective policing of the system so that it remains fair, to give genes on the two chromosomes in each pair exactly the same chance of getting into the fertilized egg. What is the point, for example, of doubling the total number of chromosomes as the first step in halving the number? Multiplying by two and then dividing by four seems an absurdly complicated way of dividing by two, but it appears to be necessary as a way of preventing cheating. Humans, incidentally, are far more at risk from trisomies like Down's syndrome than animals like rabbits that breed at much younger ages, and the risk increases with the mother's age. Ridley argues that this is related to the fact that a mother's eggs are all made at the time of her own birth, not being used until as much as forty years later. He suggests that this long period gives cheating genes the time to "learn" how to subvert the process of discarding three of the four copies of each chromosome that occurs at fertilization, so as to increase the chance of survival of a chromosome that carries a cheating gene. The book concludes with a discussion of the future of human breeding, including the question of whether cloning is likely to be feasible (yes, almost certainly) and desirable. All of the reasons why sexual reproduction exists in the first place imply that without it errors in the genome would accumulate in an uncontrolled way and extinction would follow. This would suggest that cloning will almost inevitably produce offspring weaker and less viable than the mothers of whom they are supposedly the clones.

Excellent Book - Bizarre title change:
This is another great and endlessly enjoyable work by Mark Ridley. Just to eliminate any confusion, I want to reiterate what an earlier reviewer pointed out; the title of this book is "Mendel's Demon: Gene Justice and the Complexity of Life". The American edition of the book was published with an altered title, creating the absurd impression that this book is somehow a challenge to the landmark work "The Selfish Gene" by Richard Dawkins. Some misleading reviews printed here reflect that this silliness actualy worked as a marketing tool aimed at simpletons. Mark Ridley was an undergraduate student of Richard Dawkins at the University of Oxford and is now a colleague of his there. Throughout Dawkins' work (ie. the preface to "The Extended Phenotype") he has lauded Ridley's brilliance, and he did so again in his review of this book. Anyone who is confused by the name change (a routine by American publishers that plays havoc with citations) ought not to be confused about the book's implied content; it is a fascinating read about fascinating topics, not a "challenge" to something that Mark Ridley hasn't the faintest desire to attack.

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