The Extended Phenotype

Infobox Book
name = The Extended Phenotype
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author = Richard Dawkins
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subject = Evolutionary biology
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publisher = Oxford University Press
release_date = 1982
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pages = 307
isbn = ISBN 0192860887
preceded_by = The Selfish Gene
followed_by = The Blind Watchmaker

"The Extended Phenotype" (subtitled "The Gene as the Unit of Selection", and later, "The Long Reach of the Gene") is a 1982 book by Richard Dawkins. A revised edition was published in 1999 with an afterword by the philosopher Daniel Dennett. Dawkins considers the concept of the "Extended Phenotype" to be his principal contribution to evolutionary theory. [cite web
url=http://www.richarddawkins.com/
title=Richard Dawkins Biographical Resource
accessdate=2008-02-01
quote=I suppose most authors have one piece of work of which they would say "It doesn't matter if you never read anything else of mine, please at least read this." For me, it is "The Extended Phenotype". In particular, the last four chapters constitute the best candidate for the title "innovative" that I have to offer. The rest of the book does some necessary sorting out on the way.]

Dawkins starts from the ideas of his 1976 book "The Selfish Gene", which portrayed the organism as a survival machine constructed by its genes to maximise their chances of replicating. In a much more technical presentation than the earlier book, Dawkins devotes a significant portion of this work to an attempt to rebut criticism of "The Selfish Gene".

Genes synthesize only proteins

In the main portion of the book, Dawkins argues that the only thing that genes control directly is the synthesis of proteins. He points to the arbitrariness of restricting the idea of the phenotype to apply only to the phenotypic expression of an organism's genes in its own body.

Genes affect the organism’s environment

Dawkins develops this idea by pointing to the effect that a gene may have on an organism's environment through that organism's behaviour, citing as examples caddis houses and beaver dams. He then goes further to point to first animal morphology and ultimately animal behaviour, which appears advantageous not to the animal itself, but rather to a parasite which afflicts it. Dawkins summarizes these ideas in what he terms the "Central Theorem of the Extended Phenotype":

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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. [cite book
last =Dawkins
first =Richard
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title =The Extended Phenotype
publisher =Oxford University Press
date =1999
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pages =233
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isbn=0192860887 ]

Gene centred view of life

In conducting this argument, Dawkins aims to strengthen the case for a gene-centric view of life, to the point where it is recognised that the organism itself needs to be explained. This is the challenge which he takes up in the final chapter entitled "Rediscovering the Organism."

References

External links

* [http://www.simonyi.ox.ac.uk/dawkins/WorldOfDawkins-archive/Dawkins/Work/Books/extend.shtml From "The World of Richard Dawkins"]
* [http://video.google.com/videoplay?docid=7226661303929118618 Video of cricket exhibiting behavioral extended phenotype of parasite]