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12 of 12 people found the following review helpful:
5.0 out of 5 stars
The potency of natural selection is largely underestimated, January 3, 2004
Another reader has already given an excellent summary of this book. I would like to stress only some important points in my comment.One should have a rather good knowledge of basic algebra, statistics, botany and biology to fully understand this book. This is a key text about Darwinism. Its influence cannot be overestimated, as show a few excerpts hereafter: 'there is nothing in the basic structure of the theory of natural selection that would suggest the idea of any kind of cumulative progress' and 'Evolution was a by-product of the maintenance of adaptation'.
These sentences are cornerstones of today's theories on Darwinism (see the works of the late S.J. Gould or Richard Dawkins). In a cool style, but with compelling arguments, the author wipes the floor with his opponents' theories about group adaptations, instead of adaptations on the individual level.
He also stresses the fundamentally different roles of male and female mammals for the production of offspring and the evolutionary impact of female choice. But there is more: (adapted sentence)'If some organisms were not entirely self-seeking, they, and Nature in general, would be more ethically acceptable. In most theological systems it is necessary that the creator be benevolent and that this benevolence is shown in his creation. If Nature is found to be malicious or morally indifferent, the creator is presumably too. For many, peace in mind might be difficult with the acceptance of these conclusions, but this is hardly a basis for making decisions in biology'.
This sentence is still today too big a swallow for the moral elite, unable to comprehend their own Darwinian behaviour and unable to think about the fact that 'natural selection, albeit stupid, is a story of unending arms races, slaughter and suffering' (G.C. Williams in 'Plan and Purpose in Nature'). An essential book by a superb free mind.
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9 of 10 people found the following review helpful:
5.0 out of 5 stars
'Adaptation and Natural Selection' Précis, December 12, 2002
The significance of George C. Williams analysis in "Adaptation and Natural Selection" lies in his detailed argument of why natural selection functions on the level of the individual and not the group. His defense of Darwinism rewrites the generally held assumption that adaptation characterizes species and populations, and emphasizes the role that natural selection plays in shaping the individual genotype. He thus makes possible the explanation of evolution without the use of terms such as 'group selection,' 'population adaptation,' or 'progress.' While Williams acknowledges that group selection plays a significant role in some of earth's biota, such as the eukaryotes, individual selection characterizes most organisms which reproduce sexually (xii). In the process of showing why individual selection vis a vis group selection is significant, Williams also, significantly, argues that the term adaptation cannot yet be understood in terms of any principles or procedures. The significance of Williams' starting point - a clarification of what an adaptation is and isn't - is definitional. An evolutionary 'adaptation' has specific meanings: 1) Adaptations should only be called 'functions' when shaped by design and not chance (8); 2) the level of organization of an adaptation shouldn't be higher than that admitted by the evidence (19); 3) only natural selection could have given rise to adaptations (8). Thus the scientific study of an adaptation awaits more developments in biology. Williams argues that natural selection operates and is effective only at levels measured statistically (22), for example, in terms of rates of random change, quantitative relationships among sampling errors, and selection coefficients (37). Mendelian populations selected for at the level of alleles exclusively meet these requirements (24). For Williams, natural selection of alternative alleles operates to choose between worse and better options at the level of individuals in a population (45). Genetic, somatic and ecological factors, i.e. the environment, contribute to selecting for genes. Thus, environmental factors don't directly affect populations (58). Williams identifies processes relating to the genetic system, such as sex-determining mechanisms (156), stability of genes (138), diploidy (126), introgressive hybridization (144), and the way sexual and asexual reproduction in the life cycles are distributed in the life-cycle (133) as short-term adaptations. Group survival, therefore, is a chance consequence of the these adaptations, as well as related errors such as mutation and introgression. In chapter 5, Williams also suggests that decent evidence does not exist for other mechanisms of evolutionary change or other genetic system adaptations, thus highlighting the exclusive role of natural selection in shaping life. Reproductive physiological variations of organisms seem designed to maximize organisms' reproductive success. Instances such as unbridled fecundity (161) and sex differences in reproductive strategies all suggest that an individual organism's reproductive strategy is oriented to replicating its own genetic information and not the groups' or the populations'. The significance of Williams' analysis of social adaptations (193) suggests that the benefits of cooperative social adaptations leading to cooperative relations among related individuals rest on a genetic basis; cooperation with individuals of alternative genetic information is less significant. For Williams, therefore, benefits to groups are consequences of incidental statistics; harmful group effects may accumulate in a similar way. Williams concludes (251) by arguing that there are no established guidelines to answer the question "What is the function of an adaptation?" The approaches he outlines are significant because they lay the groundwork for further developments in biology to understand what an adaptation is in terms of individual selection.
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1 of 1 people found the following review helpful:
5.0 out of 5 stars
Neodarwinian `Adaptationism' that repaired evolutionary biology , January 13, 2009
This book conquers worlds. George C. Williams `Adaptation and Natural Selection' (ANS) is subtitled `A critique of some current evolutionary thought' but is much more than just a challenge to what Williams thinks is biology gone astray. It is a landmark treatise on adaptations and a masterful revision of the current status of natural science.
William's book, first published in 1966, uses a lot of scientific language and is not much of a layman's read even though the introduction suggests it may be and definitely isn't an initiation into evolution. Most readers will probably come here having read Richard Dawkins `The Selfish Gene' (TSG) a book which refers to this source too often to count. It is more difficult than TSG and even includes a little math. At the same time when dealing with animal behaviour and directly with examples of adaptations, Williams treats the reader to some profound insights into evolution. It becomes quickly obvious why this is an extremely influential book and therefore mandatory reading for all professional biologists and students of the subject.
It is a book of three parts but all are mixed together. There is the topic of adaptations and their function, gene versus group selection and correctly applying natural selection to a biological observation. In fact the first two lead to the last point which is the goal that this book envisions bringing about.
1. Introduction
George C. Williams lays out his motive for writing ANS. He talks about how on a walk home from a lecture (Emerson 1954-55) he decided that terminology used in relation to evolution has been bandied about by biologists in ways that it shouldn't be and in particular what function an adaptation serves. With respect to the former problem, Williams thinks this is an error because the biologists are simply wrong and the latter has to do with a serious lack of scientific investigation. Williams realizes that many biologists are also heading towards a picture whereby organisms act for the greater good of the species and sees that as undermining neo-Darwinian principles where the gene is the unit of selection not the group. ANS is his case for a rethink on these current trends.
2. Natural Selection, Adaptation, and Progress
Williams lays out the framework of the post-Fisher, Haldane, Wright neo-Darwinian synthesis based on principles of Mendelian genetics combined with quantitative findings such as population genetics, computation for selection and important rates in evolution. What this does is to show how the concept of alternate alleles and their frequencies in a population can produce adaptive changes and thus evolution, all of which involves the gene as the unit of selection. The point of all of this is that groups and populations may appear as a singular organism but this is just the effect of individuals in aggregate. Williams clearly thinks the group is not subject to any form of selective pressure and that organisms are not evolving strategies to benefit the group. He reasons that the population is irrelevant to the question of adaptations. He talks about a framework for deriving the actual function of an adaptation compared to its other consequences.
3. Natural Selection, Ecology and Morphogenesis
Williams talks about how the gene is selected in ecology and how it leads to adaptations. Here Williams looks at statistical methods of providing scientific data on this idea and how it impacts on the development of an organism's life-cycle, such as birth and death rates. This means many (if not all) expressions of organisms in a group can be explained by the gene.
4. Group Selection
Now that Williams has established neo-Darwinian explanations for adaptations he turns to what many mainstream biologists have called group selection and explains their view as `biotic adaptations' (group selection) as compared to `organic adaptations' (gene selection). Williams says that if gene selection can explain the claims of group selectionists then parsimony says that gene selection is responsible. This chapter is mainly about setting up the two positions.
5. Adaptations of the Genetic System
Where possible, Williams gives the gene-view or gene explanation for the various claims made by group selectionists. This is important because if a gene-view can be given then a better explanation than group selection is on the table. He covers dominance, diploidy, sex-determination, sexual and asexual reproduction.
6. Reproductive Physiology and Behavior
Group selectionists have used reproduction and reproduction behaviour to suggest group selection and so Williams explains these in terms of the individual first and then of the gene. He treats the subject of fecundity (offspring numbers), viviparity (live birth) and gregariousness (flocking together) as evidence for gene selection and not group selection.
7. Social Adaptations
This chapter deals with the problem of altruism. Williams turns to the models provided by W.D Hamilton and explains kin selection. Models for cooperation are Darwinian and Williams brings up inclusive fitness as well as other ideas for measuring fitness. Williams points out how imperfections (with evidence for these) in parental care can lead to numerous behaviours that may appear group selective but are gene selective.
8. Other Supposedly Group-Related Adaptations
Now that Williams has dealt with the major tenants of group selectionists he turns to look at interesting but less significant examples that have been brought up for group selection. He deals with animal poisons, senescence (aging) as well as the suicidal behaviour of some communities in terms of the gene.
9. The Scientific Study of Adaptation
Williams recaps the book and ends by strongly inferring the need for a disciplined study of adaptations according to much better principles and procedures to explain the function of these features. He believes that this may even lead to a new development in the theory of natural selection. He calls this new field of research teleonomy.
The title of this book is important. Notice it says adaptation and natural selection. This is because adaptation is sometimes taken aside from evolution and also looked at in terms of its modern usage and then compared to what is known about its historical usage. Williams demonstrates that without invoking a false sense of foresight, an adaptation can be understood as a past development with a present use and so gives it purpose. That is significant because natural selection is blind but chooses adaptations in a non-random way and Williams gives more depth to that non-random part and meaning. It really is a new way of seeing adaptations from the Darwinian perspective.
One weakness that this Adaptationism may have is that this is the area of evolution that is most subject to exploitation by those who seek to undermine it, such as creationists, as well as certain palaeontologists, group selectionists and other biologists who are deeply troubled by `sociobiology' and the gene view of natural selection. They have decried adaptationism as unfalsifiable. I feel though that after reading Williams that the unfalsifiable claim is actually Williams very own position restated in a manner that is misleading by his detractors. Williams' adaptationism says we should not infer anything about the function of an adaptation until we have studied it under a much more rigorous scientific method. It is Williams who is criticizing many biologists for their lack of scientific strictness, not the other way around. If you imply that the weakness is in being able to test a adaptation hypothesis to a 100% certainty then there may be a case but this is biology and is about statistics and probability. The proof really is in the pudding, we have come a long way since 1966 and adaptationism models are only getting better. One other thing is that it is seldom called teleonomy and adaptationism seems to have stuck more. Another weakness is if Williams' really is promoting a clear-cut gene view of evolution or if he has left room for group selection. It seems that like Dawkins, Williams' acknowledges models of group selection but doesn't think they actually occur because gene selection supersedes them and the group models are vulnerable from within.
Don't be fooled by the seemingly average page count. ANS provides detailed discussions of every topic in language that is often so complex that a paragraph can take a few minutes to get through and then you are still left with questions over what he meant. The biology, let alone the evolution, is tough enough. In short this book is the kind you will need to read many times over to understand it. There are examples galore to get through and it is difficult even at the best of times. I am a biology student and I have a shelf of books on evolution and I don't understand half of what I just read here but I am sure if you stick with it you can know most of it.
One other striking thing is that the influence it has on Dawkins is nothing shy of practically providing the template for TSG. During portions I had to flip back to the cover to make sure I hadn't picked up TSG by mistake. Dawkins however popularizes this book in a different way and also extends on Hamilton's work that Williams uses for a major chapter and throughout the text. It seems an altruistic mutual endeavour that everyone can benefit from. Personally I think this could be a more important book for biology than TSG but The Extended Phenotype is more so. TSG is better writing (but remember we are talking Dawkins standard here, Williams easily sweeps the majority under the table too) but has its focus on altruism while ANS is about adaptations in the broadest sense that happens to cover topics like altruism and kin selection while Williams practically reinvents biology along the way. I really mean that when I say it. There are key books that trigger a mass brainwave in the scientific community and this is one of them.
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