169 internautes sur 179 ont trouvé ce commentaire utile
Royce E. Buehler
- Publié sur Amazon.com
Steven Jay Gould, was one of our deepest, most creative and most careful evolutionary thinkers, here delivered his magnum opus, and it inevitably rates five stars for importance. And, yes, those essays from Natural History have given you a lot of pleasure over the years. But, good Lord, look at the heft of the thing! Would you perhaps be better advised to give it a pass?
The answer is no, not if you really care about where evolutionary theory is going during the next forty years. It's true that it's longer than it had to be, and many of its luxuriating sentences are more like a bush than a tree. A good editor could have helped Gould bring it down to 1000 pages or so, and improved it thereby. But the main reason it's such a doorstop is because it's busy opening so many doors. There's far too much to respond to and critique in a review of Amazon length. So what I'm going to do is provide cheats and spoilers: I'll say what you can skip or skim without missing gist or cream, and then give a *very* brief precis of that gist.
THE QUICK TOUR.
Chiefly a summary of what's to come, a summary so dense and abstract that it's likely to convince many readers, falsely, that the book is going to be unreadable. (In the paperback edition, please add a brief glossary!) Scoop up the material on Scilla's coral (pp. 12-24) and save the rest for later.
The next 6 chapters survey the history of evolutionary thought, with a focus on old controversies Gould believes need re-opening, albeit at a higher level. As influential as Gould's been as a scientist, his real genius is for history of ideas, and these chapters are a richly rewarding read, very reminiscent of his Natural History essays in tone. But all that's needed to follow the main thread of the book's arguments are chapter 2 (an illuminating tour of Darwin's "Origin"), some talk about how Darwin dealt with the generation of diversity (pp. 224-229), the metaphor of Galton's polyhedron (pp. 342-351), and, to show what Gould is contrasting himself with, the exposition of how the "Modern Synthesis" of the 40s and 50s froze Darwinism into a rigid form (all of chapter 7).
Little is skippable. The last 50 pages of chapter seven, the punk eek centerpiece, discuss the abuses poured on punk eek by nefarious parties like Dawkins and creationists. It's juicy, but peripheral. The passages on D'Arcy Thompson (pp. 1182-1208) and on mass extinctions (all of chapter 12) are necessary to the organizational scheme, but not necessary to the logic or substance of Gould's "one long argument."
WHAT IT HAS TO SAY...
Darwin gave us a slam-dunk proof of the fact of common descent, which no scientist but the aging Aggasiz has seriously disputed since. But initially his causal theory of how it happened drew a great deal of fire. For the first 60 years after the Origin, the woods were crawling with evolutionists, some of them naturalists at the top of their game, who wanted to replace natural selection with some other mechanism. Darwin triumphed, Gould tells us, because his basic idea was right. But now the time has come for major upheaval and revision, because several of his major secondary commitments were mistaken.
What Gould says Darwin got right: Selection acting on ordinary variation, which is in some sense random, is what produces almost all evolutionary change.
Mistaken secondary commitment 1: Selection acts only on individual organisms. Gould argues that selection acts up and down the hierarchy - on genes, cells, organisms, demes, species, and clades, but (other than organisms) especially on species, because species have the sort of cohesion that makes for good selective "individuals."
Mistaken secondary commitment 2: The environment shapes almost all change, by selective pressures which mold adaptations. Gould points out that Darwin's argument for this thesis rests on the assumption that variation is "isotopic" - equally likely in all directions - and "imperceptible." He argues that recent genetic discoveries prove the contrary: deep homologies across phyla make certain major inventions such as optical lenses more likely than others, and small genetic changes in homeobox and other regulatory genes can lead to very perceptible variations, in preferred directions. And consequently, the direction of change is shaped as much by internal availabilities - creating "exaptations" - as by external selective pressures creating adaptations.
Mistaken secondary commitment 3: Selective pressure is always producing small changes, and these are always accumulating in the direction of greater fitness; simple extrapolation from them can account for the whole panoply of living things. Gould argues that (1) selective pressures fail to produce change most of the time, the phenomenon of stasis first highlighted as part of punctuated equilibrium, and (2) the changes don't accumulate. Rather, among organisms within a species, they mostly fluctuate back and forth, unless a change gets locked in by being isolated in a new species. And any trends across species are the result of selection at the species or clade levels, a kind of selection with its own emergent mechanisms not extrapolatable from Darwinian natural selection among organisms.
Is all this really all that revolutionary? Gould clearly documents how vehemently each item in the programme he outlines was denied and resisted by the old guard of the Modern Synthesis; if he seems to be making a mountain out of a molehill, it's mostly because we've grown so used to offenses against pure Darwinism in the last twenty-five years. Certainly the positions he takes open myriad fruitful lines of future inquiry. And that's really what he's after. In his "segue" between parts one and two, he notes that the time is not now ripe for still another New Synthesis; we don't know enough yet. He says that he intends this book as an antithesis to the Modern Synthesis, undoubtedly overstated and overreaching, but likely to spur the birth of the next synthesis in its own good Hegelian time. Despite (and perhaps even because) of the numerous criticisms and counter-arguments that I found myself penciling into the margins of Gould's "Structure", I think his tome will admirably serve that prodding purpose.
59 internautes sur 63 ont trouvé ce commentaire utile
- Publié sur Amazon.com
Perhpas I've read too much of Dawkins and Dennett, however, I've always thought that Gould over-hyped his own views (punctuated equilibrium, contingency, anti-reductionism, etc.). On that note, there's a lot in this book that I don't fully see eye to eye on with Gould, however, given its depth and breadth (and of course excellent writing style) this book is extremely important in that it gives an origin of species-like advocation for evolutionary theory and its many subtelies and nuances. I would consider this recommended reading for anyone interested or directly involved in any of the biological sciences, regardless of what camp you're in (i.e. Dawkins v. Gould) and that even incldes creationists, because I think if anyone opposed to evolution actually read this book cover to cover, they would have to seriously reconsider their objections. For that reason alone, even if you don't fully agree with Gould (like me) you can still appreciate this book.
207 internautes sur 237 ont trouvé ce commentaire utile
Todd I. Stark
- Publié sur Amazon.com
This book has some really great content for anyone interested in evolution and life sciences.
This is such a sweeping intellectual view of the theories that even those people who think Darwin was wrong will find some fascinating things here.
Gould does uphold the scientific view that natural selection was an important factor in the history of life, but he doesn't rely on it as the sole final solution to the challenge of finding the patterns of form and function in nature.
Gould is characteristically detailed, patient, careful, and insightful in his discussions, and there are a number of very memorable moments throughout this book. This seems to me to be one of the most, if not the most comprehensive treatment of the concepts of evolution ever written up to this point.
The downside of this comprehensive treatment is this book may be encyclopedic in places where it really doesn't need to be. Gould provides historical and intellectual background to issues in many places that don't neccessarily bolster his central theme on the structure of evolution.
This is very well-written of course, Gould seldom fails to accomplish that. But it also rambles into digressions and sidelines that distract from the structure Gould is trying to elucidate. There are long sections of punctuated gradualism and its treatment by the media that are interesting but don't seem important to the structure of evolution.
An abridged version of this book or a summary actually focusing on the structure of evolution would be extremely helpful. The encyclopedic nature of the book makes it all too easy to miss the important points in my opinion, and I do think his main points are very important.
In spite of its relatively minor flaws, I think this book is important because it may be the first book to bring together in one place the core concepts behind the many various disjoint scientific criticisms of orthodox neo-Darwinism ("ultraDarwinism") in a coherent way. Yet Gould does not throw the baby out with the bathwater. He does understand and explain well how theories of evolution lead to a spectacular vision of the majesty of life.
Gould's view of evolution is the very antithesis of the sterile view of Darwin held by evolution's opponents in terms of the meaningless acumulation of fortuitous accidents. In Gould's structure of evolution, accident and contingency play important role, but so do the underlying discernable natural laws and the constant shaping influence by the environment in myriad ways. Gould's evolutionary vision is not a mechanical algorithm for constructing lumbering robots but a process of constant artistry over the canvas of time.
I think this book is of great value both for Gould's detractors and his fans, because it makes clear virtually all of the important conceptual sticking points between the various theories of evolution.
Perhaps there has to be a Darwinist ideology lying behind evolutionary science. It seems to be the ideology that most people argue about rather than the merits of specific scientfic theories. If so, I find that Gould's expansive view of selection, adaptation, and contingency avoids a great many of the ideological pitfalls that so often seem to befall fans of the "ultraDarwinist" view of nature as a battle of selfish genes.
One of the casualties of Gould's pluralistic evolutionary structure seems to be the abomination of: "survival of the fittest" implies "might makes right". If so, there is reason for even the cultural opponents of evolution to find value in this broad and comprehensive treatment of evolutionary themes.
50 internautes sur 56 ont trouvé ce commentaire utile
- Publié sur Amazon.com
Let me say first, his final academic effort is pure Gould. If you are serious about understanding the history of evolutionary theory, it is a must read. Of course, this book is not a light read, and no one should expect it, given its his last and final academic effort. Although very verbose, his survey of evolutionary theory is very informative, and as always, detailed. If you are familar with Gould you know he writes with enough arrogant humility to make it entertaining.
But first, I must register amazement that he does not mention Lynn Margulis. To write a definitive analysis of evolution, but not include Margulis seems incredible! Why? He knows of Margulis; he even wrote a forward to one of her books. But not one reference, naja. He references practically everybody else, even Dawkins. Something is rotten in Denmark.
But, other than that flaw, Gould as usual, provides a cogent analysis of the good and bad points of evolutionary thinkers, such as D'arcy Thompson, Lamarck, Weismann giving them the benefit of the doubt and their due. I agree with Gould in trying to understand the reasoning behind each scientist's ideas and the social context behind the ideas at the time, because it helps you see when and how much the facts support the current thinking, and how, maybe one's own time biases the metaphors and perspectives.
Of course, Gould does push his own ideas, and luckily he admits that he has been wrong several times and that there will be developments in the area of molecular genetics that will undoubtly invalidate some of his facts (there aren't many authors do admit their mistakes). He finally admits to liking levels of selection and does a creditable job explaining some of the basic ideas, including credit to at least one researcher, Leo Buss. Not bad for a paleontologist, as Gould is.
His understanding of the mainstream biological evolutionary thinking will serve as a good reference point. This will serve as a reasonable textbook for the standard zoological evolutionary perspective. He carefully examines all issues from that perspective. It is quite an accomplishment. Punctuated Equilibrium, Exaptation, Drift, etc. he explains it all and well, and as always in detail (yes +1400 pages).
But unfortunately his perspective and work is limited by what he knew best, so despite it being a momentual and valuable work, its important to pick up some other books that show that the Structure of Evolutionary Theory is not done by a long shot. For Lynn Margulis' Acquiring Genomes, coming out just month later makes neo-darwinian thinking (including Gould, despite his conversion to levels of selection) look rather zoological and eucaryotic centric, and somewhat parochical in its perspective.
As long as you realize that Gould presents only part of the puzzle of evolution, I think you will realize its a magnificent piece, nevertheless.
40 internautes sur 45 ont trouvé ce commentaire utile
- Publié sur Amazon.com
After scanning some of the reviews, I find it very difficult to believe that most of the negative reviewers actually *read* the book (the alternative being Creationists simply wanted to slander a book laden with the history and present state of evolutionary theory). True, it is a long and sometimes tedious review of evolutionary theory and thought. But it should be required reading for anybody in the field of biology or paleontology. Dr. Gould (may he rest in peace) worked for 20 years on this book, and it shows through his fine prose and extensive literature review.
For younger students, it might be wise to read this with a couple grains of salt handy; Gould's opinions often overshadow other theories, particularly adaptationists (see Chap. 11).
Gould might have hoped this to be the--dare I say it--"Bible" of modern evolution. It comes close, but I found myself questioning the exclusion of some noteworthy players in the field of biology (Wallace?!) in favor of other, seemingly less important theorists.
Gould's book reads well, and the reader should not be intimidated by the length. He honors Darwinian thought like no other modern biologist could while gently re-structuring some key struts in the edifice of evolutionary theory.