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The Extended Phenotype: The Long Reach of the Gene (Popular Science)

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Biodiversity is more than a buzzword for ecologists. Variation gives life its grandeur, and Richard Dawkins gives us a description of the workings of variation. Fortunately, with a sharp mind and sharper wit, he has the ability to deliver this portrayal so that nearly everyone can understand it. That's not to say this book is an easy read. Although he delivers his narration as if sitting with you in a quiet study, you may still need to review his words more than once. That's not a challenge or a chore, it's a pleasure.

Dawkins, unlike other science writers, is forthright in declaring his advocacy in writing this book. It's a refreshing start to his most serious effort. After publication of The Selfish Gene led to a storm of fatuous criticism, Extended Phenotype comes in response with more detail of how the gene manifests itself in the organism and its environment. It's clear that Dawkins' critics, who label him an "Ultra-Darwinist" [whatever that is] haven't read this book. His critics frequently argue that The Selfish Gene doesn't operate in a vacuum, but must deal within some kind of environment, from an individual cell to global scenarios. Dawkins deftly responds to critics in describing how genes rely on their environment for successful replication. If the replication doesn't survive in the environment it finds itself, then it, and perhaps its species, will die out.

The child's favourite question, "why" is difficult enough for parents and teachers to answer. Yet, as thinking humans we've become trained to deal with that question nearly every context. So well drilled that we consider something for which that question has no answer to be suspicious if not insidious. Part of Dawkins presentation here reiterates that there is no "why" to either the process of evolution nor its results. It isn't predictable, inevitable or reasonable. It's a tough situation to cope with, but Dawkins describes the mechanism with such precision and clarity, we readily understand "how" if not "why" evolution works. We comprehend because Dawkins does such an outstanding job in presenting its mechanics.

This edition carries three fine finales: Dawkins well thought out bibliography, a glossary, and most prized, indeed, an Afterword by Daniel C. Dennett. If any defense of this book is needed, Dennett is a peerless champion for the task. Dennett's capabilities in logical argument are superbly expressed here. As he's done elsewhere {Darwin's Dangerous Idea], Dennett mourns the lack of orginality and logic among Dawkins' critics. Excepting the more obstinate ones, these seem to be falling by the wayside. It's almost worthwhile reading Dennett's brief essay before starting Dawkins. It would be a gift to readers beyond measure if these two ever collaborated on a book.

Richard Dawkins is one of the most interesting popular science writers working today, and usually his books are filled with insight and perception about evolution (and other topics), written in clear and effective prose. This book is different from most of Dawkins's books, as it targets biologists rather than laypeople, and so it is a much more frustrating and difficult reading for such readers.

Frankly, if you are, like me, a lay person, don't read this book before reading other books by Dawkins, most notably The Selfish Gene, but also other stuff by him. I doubt I would have understood this book had it been my introduction to Dawkins's ideas. The glossary, though helpful, is far from complete and rarely detailed enough.

But for all this, The Extended Phenotype is richer in observations and ideas then any other book by Dawkins I have ever read. Dawkins says this is his best book, and you can see that he has a point.

The book has three main themes. The first is discussion of left over issues from The Selfish Gene, answering criticism and elaborating on the ideas in that book. The second is clarifying some issues in discussion of evolution, such as replicators and vehicles, fitness, etc. The third one, and the one for which Dawkins is most proud is his 'Extended Phenotype' - the concept that genes operate on the enviornment, and that the body (the individual organism) is a link in the chain of orders passing from DNA to the external phenotype - beaver dams or host behaviour that helps the parasite, or any other activity that helps the genes.

Frankly, the concept of the extended phenotype is best explained in the chapter about 'The Long reach of the gene' in the new (1989) edition of 'The Selfish Gene'. The book is actually best when Dawkins deals with the two other themes -difining genes for example, and discussing replicators. Those chapters are masterworks of clear, essential thinking, of which Dawkins is always a champion.

Finally, one would wish that the book was updated. Many discussions are based on information that at the time was brand new, and follow up would be useful. uinfortunately, Dunnet's afterword does not do the trick, and is more of a hymn to Dawkins (albeit a justified one) than anything else.

'The Extended Phenotype' is not an easy read, but it is definetly worth it.

One of the reviewers here claims that Dawkins doesn't get that evolution doesn't see individual genes, but only individual organisms. This person isn't getting Dawkins!! Dawkins is saying individuals are a products of complex genetic interplay and that the influence of genes (singly or in groups) can extend outside the individual. The individual-centric viewpoint is only a viewpoint.

In fact individuals are NOT selected by natural selection (all humans that have ever lived so far have eventually died!) GENES are selected -- albeit in groups since they reside together in an individual (this is their mini-environment)--though not permanently since recombination ensures genes will be shuffled regularly into new, though similar, micro-environments. My grandfathers genes live on -- though my grandfather is dead. Dawkins is repsenting a different viewpoint on GENETIC selection as he explains in the preface of the book. And it is a brilliant viewpoint. Genes have an influence on the world, that includes both the characterisitics and behaviors of individual organisms in which they reside as well as the behavior of organisms and artiftacts outside that individual. Really one of the great books in evolution.

Let me put it another way--Is a physicits wrong when he claims the desk I sit at is mostly empty space? Sure looks solid to me, I say. But at the micro-level the desk is indeed mostly empty space and if neurtrinos could talk they would surely attest to this fact. One has to open one's mind to see that Dawkin's gene-centric perspective is as valid as the old-fasioned model and indeed leads to new insights and illuminations. That's thw whole point of him presenting this view after all!!! Isn't that waht good theory is supposed to do?

Richard Dawkins claims that his most significant contribution to evolutionary biology is contained in the final chapters of "The Extended Phenotype". Be that as it may, he's most widely known as the author of "The Selfish Gene (1976)", where he championed the gene's eye view of evolution and coined the term meme as the basic unit of cultural evolution. That said, I consider "The Extended Phenotype" to be the best in Dawkins' canon, which puts it high in the running for the best book on evolutionary biology.

Dawkins' calls this book a work of unabashed advocacy. In fact, all of Dawkins' books advocate a particular reading of evolutionary biology, often parodied as ultra-Darwinism by his critics (including Jay Gould, Niles Eldridge, and Richard Lewontin). Ultra-Darwinism, simply put, is the belief that evolution proceeds, via natural selection, to gradually substitute alleles over long stretches of time. Ultra-Darwinism also encompasses the doctrine of adapationism, or the belief that specialized structures were molded by natural selection as adaptations to a particular mode of life. Dawkins' makes the case that what his critics often call Ultra-Darwinism is in fact quite orthodox neo-Darwinism, not a bold fringe-interpretation. Those who disagree with Dawkins will find no more apt defense of his beliefs about evolution than in this book.

In the initial chapters of "The Extended Phenotype", Dawkins addresses critiques of "The Selfish Gene". Oftentimes these critiques are based on a gut-reaction or incomplete reading of his ideas, but those who rightly read both Dawkins and his critics will find his counter-arguments enlightening, albeit overwhelming. Dawkins also disrobes the nature vs. nurture debate in one of the most compulsively readable chapters of this book, defining just what it means when an ethnologist talks about a gene for a behavior, or for a morphological trait, or anything beyond the linear sequence of amino-acids that molecular DNA directly encodes. Dawkins re-hash is anything but repetitive. Each chapter is so dense with interesting ideas and concepts that readers will feel inclined to set the book down and discuss it with anyone who will listen at each available stop-point.

It's not until the final few chapters that Dawkins even directly discusses idea of an extended phenotype. He hints at it all along, and you'll notice that once you're comfortable talking about genes "for" eye-color, or hypothetical blue-beards, or particularly stinky arm-pits, realizing that the route from gene to phenotype may be tortuously indirect (or without context unless kept under a specific set of environmental cues), the idea of the extended phenotype is no radical departure. Extended phenotypes include spider webs, termite mounds, and beaver dams--that is, any part of an organism's abiotic environment that is modified in a particular way according to that organism' genetic endowment. I think, more so than the radical idea of genes encoding for non-bodily artifacts, the point of the final few chapters is that once you've started to think of extended phenotypes as a logical extension of evolutionary theory, you've come to look at the organism, the gene, and the environment just the way Dawkins does. Frankly, I think this is the best way anyone has come up with.

The new-edition of the book contains an afterward from philosopher Daniel Dennett (author of "Darwin's Dangerous Idea") that makes for an enjoyable read. It's important to note that "The Extended Phenotype" is not a popular-science book for the casual reader. It certainly demands some degree of familiarity with evolutionary theory on at least an undergraduate level. Non-biologist can still enjoy it, but it will require hard work and an attention to detail to stay on track in the more technically pernicious chapters. Another comment--the margins of the book are to narrow, the vertical spacing is too small, the font is too small and (in my opinion) too dim. Everything about this book other than the words and the message itself stinks. I hope it's re-released in a better paper-back form.

The first thing I will say about The Extended Phenotype (EP) is that it is far from the first book on evolution you should read and as a stand-alone Dawkins book it is a poor choice because it is a sequel of sorts to The Selfish Gene (TSG) and there is much more going on besides. I would suggest Climbing Mount Improbable or The Blind Watchmaker first. Both of those books by Dawkins have a much broader, more generalized, look at natural selection and evolution. TSG covers the basics of the gene view as the unit of selection. After you do this then I recommend that you read what has become known as the "Darwin Wars" to some (it is not a book but a collection of writings). The two main critics are Stephen Jay Gould and Richard Lewontin. There are two articles you should read from them before EP. They are called Darwinian Fundamentalism by Stephen Jay Gould and The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme: by Stephen Jay Gould and Richard Lewontin. Both articles appear on the unofficial Stephen Jay Gould archive on-line. You can read about the Darwin Wars in general there. Author Daniel Dennett has much to say on this also.

EP is a two-fold book. In one respect it is an apologetics in response to an anti-selfish gene (calling this version of neo-Darwinism, Darwinian fundamentalist or the adaptationist program) movement that was also associated with the anti-sociobiology criticisms of E.O Wilson's work. In other respects EP is a straightforward work on evolution that is geared towards professional biologists in an attempt to take matters raised in TSG and to develop them further to encompass how the gene is expressed in the phenotype from the view of the gene and not the traditional view of the individual. Like TSG it will be anti-group selectionist. It is also very much a book on adaptation from the neo-Darwinian perspective. This book will enjoy a dog ear phenotype for those who get it.

Chapter 1 - Necker Cubes and Buffaloes
Dawkins suggests that EP is not really saying anything different than what we understand about phenotypes today. He suggests however that the gene view of phenotypes as adaptations in evolution offers much more for the evolutionist.

Chapter 2 - Genetic Determinism and Gene Selectionism
This is largely an apologetic for those who misunderstood The Selfish Gene to mean that people are puppets of our genes (some foreign book covers with puppet-type illustrations may have implied this) and who didn't get that the robot examples were just analogies. Dawkins sets the record straight, genes are selected for, they give rise to phenotypes and the environment has an impact on the phenotype so it is not possible that everything is determined by the gene alone. Dawkins brings up embryology (developmental biology) to put this gene myth to bed. However he says that it is important to understand that without genes, the phenotype could never be expressed at all. More crucially, how the gene is expressed needs to be understood in a statistical sense. Dawkins even gives examples where talking about traits in terms of genes is misguided although in the end a biologist is forced to admit that without genes the phenotype cannot appear. Genes do determine the phenotype but there is a degree of variation there. The rest of the book talks about what that degree is and how to understand it.

3 - Constraints on Perfection
This is the correct version of the adaptationist program as taken from the standard model of neo-Darwinian adaptation. It shows that the Panglossian critic is not the neo-Darwinian view at all. The Panglossian sees all adaptations as being the best for that environment. The neo-Darwinian doesn't think this. Dawkins tells us that to see all adaptations as just roads to the perfect adaptation ignores physiology constraints such as biochemical restrictions. He gets some less likely suggestions out of the way like how neutral theory shouldn't apply because it's neutral on adaptations, how allometry is probably only a minor role in adaptation and how pleiotropy is influenced by developmental biology in separating out the better phenotype. So this leaves the way for what he sees as the more important considerations for adaptationists in the form of time lags (environment changes that the organism has yet to catch up with), historical constraints (how previous adaptations restrain future ones), available genetic variation (one variation that was sufficient may have taken off before a better variation arrived), constraints on costs and materials, imperfection levels (genes in populations can produce adaptations that fly in the face of Panglossian adaptation) and malevolence (the environment can act against the adaptation, statistically).

4 - Arms races and manipulation
Using various examples Dawkins convinces the reader that organisms can be in the business of directly manipulating other organisms to their own advantage and that evolution causes an arms race between manipulators and victims. The parts on slave making insects can get very heady but it is worth the effort and the hymenopteran sex ratios may be the most difficult topic Dawkins has ever covered in any of his books... but it is nearly equally as difficult as other topics that lie ahead.

5 - The Active Germ-line replicator
This chapter is devoted to undermining the individual or the group as the unit of selection and promoting the gene as the unit of selection. The gene is reduced, Dawkins introduces the concept of replicators and vehicles, describes each in terms of natural selection, make precise definitions of his replicators (active germ-line replicator) and takes on his critics. It is a genetics heavy chapter.

6 - Organisms, Groups and Memes: Replicators or Vehicles?
On the bases of the previous chapter Dawkins applies the concept of the replicator and vehicle to real world scenarios. This chapter gives one of the best explanations of Gould's and Elderage's Punctuated Equilibrium in print anywhere. It appears Dawkins subscribes to this version (there is a debate over what Gould's and Elderage's version is) in principle and then makes probably his first concession that the unit of selection now has to be expanded from the gene to include the species, but he asserts that this is not group selection and that species selection cannot be responsible for any sort of serious biological complexity and is therefore just an outcome of a trend. He then defends his position on the meme and tries to clarify more about replicators and vehicles.

7 - Selfish Wasp or Selfish Strategy
This chapter is about ethology research that Dawkins did on wasps to show why the gene view is important because it produces different results. It is a technical chapter where Dawkins also visits Maynard Smith's concept of the evolutionarily stability strategy (ESS) and does an analysis of the experiment from the view of the gene and then the view of the individual. He believes the gene view gives more accurate results.

8 - Outlaws and Modifiers
This is a challenging chapter that takes a look at natural selection in action within an individual between their own genes. Dawkins covers a number of phenomena within cells that cannot be explained without invoking a gene view. He then deals with the problem of relative-recognition and how the selfish genes are actually deciphered by organisms.

9 - Selfish DNA, Jumping Genes, and a Lamarckian Scare
This takes a look at `Junk' DNA and Dawkins gives his own explanation for it. He addresses the genes that depart from DNA strands in the cell and their fate or evolution. He then talks about the problem of evolution of sex and meiosis before presenting a research paper that was almost Lamarckian and helps the reader to understand Weismann's dogma.

10 - An Agony in Five Fits
Dawkins looks at five different ways in which scientists have used the term `fitness' in relation to evolution. He goes through the pros and cons of each model.

11 - The Genetical Evolution of Animal Artefacts
200 pages in and Dawkins now addresses what is the central theme of this book, The Extended Phenotype or the long reach of the gene. Dawkins believes that he has established that behaviour is genetic and is subject to natural selection so there is no reason not to see the results of behaviour, such as the construction efforts of organisms, to be treated as phenotypes and therefore subject to natural selection. He uses Caddis houses, spider webs and beaver dams as examples. Then he introduces group construction and though a gene view using the example of termite mounds, explains that these artefacts are constructed by a combination of gene variation, roles in the colony and the use of cues and signalling. There is a very interesting bee swarm observation at the end.

12 - Host phenotypes of parasite genes
Here Dawkins looks at how parasites modify a host organism so that the host becomes more suitable for them to use even at the expense of the host. He brings up a number of examples mostly concerning flukes, snail shell size and snail antlers. He then suggests a new type of biologist who should look beyond just the phenotypes that appear on the organism to include other organisms. He proposes that two biologists studying separate types of organisms that interact could be incorporated in one `extended view'. He calls this type of biologist the `extended geneticist'.

13 - Action at a distance
This gives some more examples of the extended phenotype in action with more snails and the Bruce effect with mice. Dawkins states the formula of the extended phenotype, `An animal's behaviour tends to maximize the survival of the genes 'for' that behaviour, whether or not those genes happen to be in the body of the particular animal performing it'. He questions over what distance this can extend to but expects that its effects diminish with longer distances. He sees no reason why it can't be across continents. He talks about Lovelock's `Gaia' hypothesis and disagrees with this saying that there is no mechanism that supports a feedback system of that type. Dawkins believes the selfish gene view is the only way to view biota on this planet. The chapter closes by Dawkins quoting important evolutionists who appear to critic the gene view and answering or commenting on their statements.

13 - Rediscovering the organism
This chapter takes a look at the individual in a new that that examines the roles of growth and reproduction and how development cycles or stages of growth has advanced and sped up evolution. He finishes by recapitulating everything. You get a glossary of evolution terms at the end.

EP does suffer slightly from being apologetic even if Dawkins does try to overcome it. EP does have those parts in its shadows but to be honest I quite like its apologetic nature. However it takes a fair few chapters before it gets into the gene as the unit of selection (around 4 or 5) and the extended phenotype doesn't really emerge until chapter 11. It is worth the wait or battling through some of the most complicated examples for a laymen's book on evolution, but Dawkins states that this is also an advanced evolution book for professionals. Essentially if you are brave enough to read it, then go for it but don't be surprised if you can't follow it. I will admit that even though I am a biology undergraduate I didn't understand a lot of it and it demands several readings.

The argument for the extended phenotype strikes the reader as something so obvious that it is surprising that Dawkins thinks he is establishing something new. Biology doesn't rule out what Dawkins is presenting and in fact states as much, but the language of the extended phenotype is rarely emergent in other works on biology. This is probably due to biologists being inclined to use the individual as the unit of selection, rather than the gene and also apprehension that using the principle of the extended phenotype could be wrong. Dawkins sets the record straight. Talk in terms of genes and the extended phenotype is a fact.

One weakness that does emerge is the criticism that even blind natural selection cannot see genes, only the individual, but Dawkins rightly brushes this off as merely a stiffness of thought and that the genes are still being selected but the criticism goes further to say that genes are selected in groups, not as discreet units. Dawkins has to make the concession that it is genes coexisting (or for their capacity to cooperate with other genes) that are the unit of selection. Is this a form of group selection after all? Dawkins implies that this is a different sense completely and that it is really only the germ-line genes that are being selected. It is frustrating because the reader can see that he is right to forward this gene view only to end up with a fact of evolution that genes cooperate and coexist so that they are potential candidates for a selection process that chooses them in groups. Can you imagine them as discreet units? Yes of course, and this is exactly what Dawkins wants us to see, but nature picks them out in aggregate and not discreetly. Whatever way Dawkins tries to cut the cake of phenotypes it looks like he has to eat a slice of group selection to have a filling of gene selection. Look at the problem the gene view has with selecting deleterious genes, like in a heterozygous state. The only way it seems to overcome this problem is to allow grouped genes as the unit of selection otherwise we end up saying that natural selection is selecting for genes that are disadvantageous to the organism. However here comes the genius, Dawkins rightly suspects that this not the case. Natural selection is not selecting disadvantageous genes, but meiosis in terms of reproduction is reproducing advantageous genes but recombines them in a way that makes them disadvantageous. It seems this view saves the gene view except for one small glitch. Meiosis itself cannot escape its own genes. Dawkins however does bring up one more salient point. Embryology or the development of the biology of the genetic influence is subject to change. Since development is so variable how can it be selected? It isn't because there is a chance the phenotype will not be reproduced precisely the same way. It's the genes that are ultimately selected not developmental biology. Dawkins saves the gene view in light of his critics confusing genetics with embryology. That slice of group selection now appears to be composed entirely of selfish genes. Maybe the cake doesn't taste so bad in light of this.

Dawkins asserts that this is his most important book. I would agree, it ranks as his most complex work. Not to mention that his critics haven't been able to answer it since 1983! and just rehash the same arguments Dawkins addresses in this book. I placed The Selfish Gene as the most important works on evolution outside of Darwin's and R.A Fisher's. I am inclined to push The Extended Phenotype into a slot above TSG. EP is more powerful than all of Dawkins' works combined... and a host of other books on evolution to boot. Dawkins works always resonate in my mind in ways that change my worldview but the extended phenotype is the nuclear detonation of conscious expanding scientific experience on a magnitude that intensifies with every new insight it discloses.

If you haven't read "The Selfish Gene", stop, go back and read that book. If you really _get_ the message presented there, that replicators (DNA) have built all of the life on earth, then this book is not as revealing as Dawkins seems to think it is. By this, I mean that there are no knew insights, only explanations of how DNA behaves.

I can only suppose that most readers of TSG are not actually aware of the full implications of the idea he presented in that book. If you understand that DNA builds organisms, and that genes cooperate to the extent necessary for each to insure its own continued existence, then the idea that genes in different organisms, species, etc... can cooperate is not surprising.

The reader will definitely learn a lot about how genes cooperate and compete with one another, and for this alone, the book is worth reading. But, if you understand that genes make organisms (when it suits them), and that organisms do not _use_ genes to reproduce themselves, then you may be disappointed to find that this book lacks something that a groundbreaking book like The Selfish Gene necessarily contains.

Still, highly recommended, a powerful exploration of replicator phenomenology.

(Note: if you have read this book, and think I've missed the point, please email me your interpretation, or where you think I've gone wrong.)

This is a long and difficult book, although not as long and difficult as it might be if it had been written by somebody without Richard Dawkins' gift for clarity of thought and expression.

The crux of Dawkins' thesis is expressed early on and much of what follows is a very detailed supporting argument. What he wants us to see is that the "selfish gene" has a reach that extends beyond the confines of the individual organism that houses the gene. The phenotype of our genes is the human organism in all its glory; however the extended phenotype of our genes is not only the human organism but part of the environment in which the organism finds itself. In other words, the gene has the power to influence not only our behavior but the behavior and structure of elements in the world in which we live.

This thesis is not as striking to me as it has been to many others mainly because I have studied Eastern religious views, and it is a tenant of such views that the distinction between ourselves (the "selfish organism," in Dawkins' terminology) and the environment is an artificial one, an illusion actually. We are part and parcel of all that is around us and within us, and the boundary of our skin is merely functional. We cannot be understood by looking at only our bodies. Dawkins makes the point that looking at a beaver and microscopically examining it and its genes is not sufficient to an understanding of what a beaver is. We have to also consider the dams that the beaver builds, the trees that it gnaws down and even the streams that it dams and turns into lakes.

Presenting a point of view somewhat at odds with that of Dawkins (and one that I think that Dawkins does not sufficiently appreciate) is Franklin M. Harold in his book, The Way of the Cell: Molecules, Organisms and the Order of Life (2001). He writes, "Organisms process matter and energy as well as information; each represents a dynamic node in a whirlpool of several currents, and self-reproduction is a property of the collective, not of genes.... DNA is a peculiar sort of software, that can only be correctly interpreted by its own unique hardware.... [S]ending aliens the genome of a cat is no substitute for sending the cat itself--complete with mice." (p. 221)

Dawkins tries to discount the view of those he calls "group selectionists" who see life from a "group benefit" viewpoint. Dawkins has, since writing this book, stepped back from this position to allow that some group selection may take place. I believe some day he may see the world not from a "selfish gene" point of view, and not from a "selfish organism" point of view, but from a "selfish ecosystem" perspective--well, more likely his successors will see this, since the work of a lifetime is not easily amended in one's later years.

Dawkins gives what he calls "our own 'central theorem' of the extended phenotype" on page 233: "An animal's behaviour tends to maximize the survival of the genes 'for' that behaviour, whether or not those genes happen to be in the body of the particular animal performing it."

This is a mouthful. Clearly we can say that the genes of the reed warbler code for behavior that benefits the genes of the cuckoo who has laid its egg in the warbler's nest. This is what Dawkins has in mind. But then arises the question, "how far afield can the phenotype extend?" Here Dawkins gets cautious and writes, "The farthest action at a distance I can think of is a matter of several miles." (p. 233) Note the chosen terminology, "action at a distance." This is from physics of course causing Dawkins to ask if there is "a sharp cut-off" of the genes' reach or "an inverse square law" at work?

It is here that I believe Dawkins has come so, so close to that which he will not see (or couldn't see then), namely that everything works toward an ecology and that the idea of selfish genes and selfish organisms is a limited view. In truth the reach of the genes should be governed by something like an inverse square law since humans are now reaching beyond the solar system.

When we look at such great distances we might want to credit the dreaded and verboten "group selection" that Dawkins is at pains to reject. Just as some see our earth as "Gaia," an organism itself, so too might we see those organisms that have the means to survive the destruction of the home planet by migrating to other planets as being selected by group as opposed to other groups who have no such ability. Planet A produces beings that extend beyond their solar system; planet B produces beings that do not. Both planets blow up. Who is "selected" by the (extended) environment and who is not?

Dawkins is one of the geniuses of science, and I don't mean to argue with the great insights he has brought to biology, but my point is that it is always something of an artificiality to speak of living systems as confined to one level of existence or expression. We may think of earth creatures as being completely separate from the rest of the universe, yet without the sun, 93 million miles away, we would not exist; and come a supernova even many light years away, we will be affected.

So all is one and one is all in some extended sense. And using the word "selfish" (as Dawkins knows) at any level of life is merely to be anthropomorphic.

Daniel Dennett, in a new afterword written in 1999, asks if this book is science or philosophy, and he answers both. I agree, and it is science and philosophy of the highest order, aimed equally at the professional and at the educated layperson.

This book, while more technical than Dawkins' other works, is still easily accessible to any layperson willing to think long and hard about the concepts (and to use the glossary!). The book's basic premise - essentially, that a beaver's dam should be considered as much a product of beaver genes as a beaver's body - is right on target. Not to mention that seeing this type of old problem in a new light is becoming Dawkins' specialty - in "The Selfish Gene", he popularized and expanded the theory of gene-based natural selection and also developed the concept of memes as the basis of cultural evolution; now he shows that phenotypic effects extend far beyond the boundaries of the body.

Dawkins also takes this opportunity to expand on his theory of the replicator, or replicating entity, and develop its classification further. I'd recommend reading the book after The Selfish Gene just to get the concepts down (unless you're familiar with evolution - and NOT of the punctuationist variety!).

Written just a few short years after his monster hit The Selfish Gene, The Extended Phenotype is the work of his most directed at fellow professionals and not members of the lay public.

So viewed, it can be a difficult read.

But once read, it succeeds in its various multiple missions (like building on points made in Selfish Gene) but most notably in advancing the idea that the long reach of the gene can extend beyond the individual in which it resides to have greater effects on other creatures and the biosphere itself.

A mundane example of this process is a beaver dam. Obviously more familiar examples are human made artifacts. Less obvious are creatures that live in symbiosis with each other, relying on their various activities to propogate themselves.

This last feature is enormously important. Housed within each cell of your body are about a thousand mitochondria or tiny single celled creatures (I'm calling them that because they each have their own DNA) which assist in the process of energy production. The contemporary wisdom is that muliticellular life would be impossible without them and the symbiotic relatonship we have with them.

In this way, the grander issues raised by an examination of the long reach of the gene have bearing not only on the rise of multicellular life but the potential for finding it elsewhere in the universe.

In other words, I would recommend this book highly but perhaps only after first reading his Selfish Gene and also his Ancestor's Tale.

I was impressed with Richard Dawkins' "The Selfish Gene" and this book is the logical followup. It is more complicated and therefore more difficult to comprehend than the former. So that makes the very small type all the more annoying -- it adds to the difficulty. Seriously, the type size is among the smallest I have seen in any modern mass produced book.

Anyone know if any of the earlier editions have larger type?