Extended phenotype

Brandon, R. (1990), Adaptation and Environment, Princeton University Press, Princeton, NJ. Cartwright, N. (1983), How the Laws of Physics Lie, Oxford University Press, Oxford, UK. Dawkins, R. (1982), The Extended Phenotype, Freeman, San Francisco, CA. 

Dawkins, R. (1982), The Extended Phenotype, Oxford University Press, Oxford, UK. 

See, for instance, his discussion in the first two chapters of The Extended Phenotype The Gene as the Unit of Selection (Dawkins, 1982). 

Schuck-Paim, C. (2000). Orb-webs as extended-phenotypes web design and size assessment in contests between Nephilengys cruentata females (Araneae, Tetragnathidae). Behaviour 137 1331-1347. 

Hughes, D. P. (2008). The extended phenotype within the colony and how it obscures social communication. In Sociobiology of Communication, ed. P. D Ettore and D. P. Hughes. Oxford Oxford University Press, pp. 171-190. 

You may be familiar with Richard Dawkins s books The Selfish Gene and The Blind Watchmaker, and may perhaps have learned most of what you know about evolution, particularly the evolution of behavior, from these excellent sources. His second book. The Extended Phenotype, is less well known, and that is a pity, because in many ways it is his finest achievement. Nonetheless, even the most lucid books contain some obscure passages, and you could weU have been puzzled by a couple of pages of The Extended Phenotype that deal will the theory of modifier genes, which R. A. Fisher proposed in 1930 to explain why the phenotypes of some genes are dominant whereas others are recessive, phenotype being a technical term for the specific set of observable characteristics that indicate the presence of a particular variant of a gene. 

It may well be true, as Dawkins asserts, that by 1958 the modifier theory was so well accepted, along with Fisher s view that dominance must be an evolved property because it has selective advantage, that he felt no need to justify it when he wrote the second edition of The Genetical Theory of Natural Selection indeed, the theory was still well accepted in 1981, when The Extended Phenotype was written. Coincidentally, however, 1981 was the year in which the matter was clarified once and for all by a landmark paper by Henrik Kacser and Jim Bums, and, as we shall see, their explanation differs... 

Richard Dawkins (1981) The Extended Phenotype, Oxford University Press, Oxford. [Although this is directed more toward professional biologists than Dawkins s other books, it is readily accessible to the general reader.]... 

POPULATION- AND LANDSCAPE- LEVEL DYNAMICS BIMODAL EQUILIBRIA, ALLEE EFFECTS, AND EXTENDED PHENOTYPES... 

Once data from thousands of different sequences derived from thousands of different tissues has been compiled, bioinformatic analysis of the data allows us to identify genes that show restricted patterns of expression, assisting in both annotation of function, and association with phenotype. This analysis can be extended to look for novel markers or targets, by analyzing those novel sequences that are co-expressed with known markers or targets. This has been applied to a number of diseases already, such as prostate cancer and Parkinson s disease [120, 164]. 

Comorbid conditions can also provide a way to either narrow or extend the phenotype. An analysis of the COGA data showed a very strong signal for the broadened phenotype of alcoholism or major depression this was located in the same region of chromosome 1 in which the alcoholism phenotype gave a signal [55]. The data for the combined phenotype was much stronger than that for the alcoholism-only phenotype. 

In Gram-negative bacteria the cell wall is only about 3 nm thick, and located in the extended periplasmatic space between the inner membrane (IM) and an additional outer membrane (OM). The lipid monolayer in the outer leaflet of the OM contains about 90% lipopolysaccharides (LPS). LPS consist of Lipid A and an oligosaccharide component, which is highly specific for individual bacterial species and phenotypes [108, 114]. 

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