— The Long Reach of the Gene
Select Quotes
9 Selfish Dna, Jumping Genes, And A Lamarckian Scare
‘there is a good correlation between strong r-selection, small cells and low C-values on the one hand and between K-selection, large cells and high C-values on the other’. – Page 158
The selfish DNA hypothesis is based on an inversion of this assumption: phenotypic characters are there because they help DNA to replicate itself, and if DNA can find quicker and easier ways to replicate itself, perhaps bypassing conventional phenotypic expression, it will be selected to do so. – Page 158
I had my doubts about whether his could really coincide with those attributed to him, until I recalled his, to me always slightly puzzling (see page 22), remark that ‘The main weakness of modern evolutionary theory is its lack of a fully worked out theory of variation, that is, of candidature for evolution, of the form in which genetic variants are proffered for selection. – Page 165
Any gene in a ‘somatic’ cell which is a candidate for proviral conveyance into a germ cell is, by definition, a germ-line replicator. – Page 169
The general point is that cellular selection cannot achieve the speeding up of evolution attributed to it, if the adaptation of interest has to develop on the slow scale of multicellular cooperation. – Page 171
An animal that is well adapted to its environment can be regarded as embodying information about its environment, in the way that a key embodies information about the lock that it is built to undo. A camouflaged animal has been said to carry a picture of its environment on its back. – Page 173
But you cannot reconstruct an individual’s genome by inspecting his body, any more than you could reconstruct William Shakespeare by decoding his collected works. – Page 175
10 An Agony In Five Fits
‘Genes cannot be selfish or unselfish, any more than atoms can be jealous, elephants abstract or biscuits teleological’ (Midgley 1979; see reply in Dawkins 1981). – Page 180
12 Host Phenotypes Of Parasite Genes
Is it just an accident that we sneeze when getting a cold, or could it be a result of manipulation by viruses to increase their chances of infecting another host? – Page 220
‘In non-living habitats, an organism either exists or it does not. In the cell habitat, an invading organism can progressively lose pieces of itself, slowly blending into the general background, its former existence betrayed only by some relic. – Page 222
Maximizing the amount and diversity of DNA in the biosphere is the concern of nobody and nothing. Rather, each small piece of DNA is selected for its power to maximize its own survival and replication. – Page 223
13 Action At A Distance
Putting these three things together we arrive at our own ‘central theorem’ 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. – Page 233
Afterword By Daniel Dennett
The Selfish Gene was written for educated lay readers, and glided over many of the intricacies and technicalities that a proper scientific assessment needs to consider at length. The Extended Phenotype was written for the professional biologist, but so graceful and lucid is Dawkins’s writing that even outsiders who are prepared to exercise their brains vigorously can follow the arguments, and appreciate the subtlety of the issues. – Page 266