BOOK SUMMARY: The Selfish Gene



SUMMARY: The Selfish Gene
Copyright © 1998 by: Sebastian Molnar

Richard Dawkins' (1976) contention is that 'survival machines' (i.e. individual organisms) are designed by -- and designed to preserve -- selfish genes. He described "selfishness" and "altruism" as 'unconscious purposive behavior' -- that is, there is no thought behind a gene's action, but simply automatic. Dawkins defined "selfishness" as a behavior that increases the chances of survival (e.g. increases the number of copies) of genes in one individual at the expense of another. In other words, it is the effect of a behavior that increases or decreases gene survival. Dawkins' approach is similar to Lorenz's (1963), in that the biological aspects must be considered in order to understand the essence of certain behaviors. What is different about Dawkins' argument is that he uses genetics as well as economics (e.g. costs and benefits) and principles taken from Game Theory, rather than simply assuming certain drives that shape behavior -- which Lorenz does.

With a reductionist view, focusing on genetics, Dawkins disputes Lorenz and others in their use of evolution by natural selection -- i.e. the 'good of the group view' is wrong. In contrast, Dawkins takes a 'good of the gene' view on evolution. Natural selection acts on the individual's genes or rather, on the phenotypic effects of an individual's genes - not on the group as a whole. Genes build 'survival machines' or individual organisms. Genes are selfish in that they build survival machines to increase the number of copies of themselves, thus survival machines tend to be inherently selfish. Individuals that form groups do so for the benefit of their selfish genes (e.g. there is safety in numbers; safety for genes). An individual may act altruistically, but does so for its own gene preservation -- not group preservation.

Dawkins stated three properties common to all replicators: 1) longevity, 2) copying-fidelity, and 3) fecundity. These properties need to be considered to understand fundamentally, how replicators survive or persist since life is based on replicators. Also, replicators are 'unconscious' and 'blind to the future'. There is no thought directing their actions. They are selected for depending on the prevailing conditions in the environment (whether the environment is a physical geographic location, inside a group, or inside a brain). Replicators can change or mutate, causing variation. It is this variation on which natural selection works that leads to evolution.

Genes have multiple effects. Dawkins used this fact to show, theoretically, that a gene can influence a behavior in addition to some physical biological function. Genes not only have multiple effects -- they work together, or cooperatively in the individual. Dawkins used a 'rowing team' to illustrate the point. 'Gene complexes', or perhaps whole genomes, may be responsible for certain behavior patterns, while single genes code for certain components of the behavior. There is one slight problem with this line of reasoning. There has not been very much research on the genetics of behavior, so Dawkins' argument is mainly theoretical. However, this does not mean that genes don't have behavioral effects (see another of his books The Extended Phenotype). Also, genes code for 'potentials', not 'absolutes'. Gene-environment interactions must be taken into account (i.e. genes may act differently in different environments -- Dawkins mentions this in Unweaving the Rainbow).

An ESS (evolutionarily-stable-strategy) is "a strategy that does well against copies of itself."[p. 282] Once a behavior - rather, a 'stable ratio' of behaviors dominates a population, it tends not to change dramatically. This explains the persistence of certain behaviors in a population. 'Cost and benefit' (Game Theory) calculations describe how an individual - without the individual actually doing the calculations - responds to a situation and acts appropriately (whether aggressively, altruistically, or otherwise). This explains discriminative behavior (e.g. acting altruistically towards another; or killing another individual for a specific purpose). Genetic relatedness can explain characteristics of altruism, and why it might be beneficial to behave that way. Each of these methods are useful in describing or analyzing various aspects of certain behaviors, but none of them explains how 'gene recognition' by one individual to another might be carried out in practice. As already mentioned, genes have multiple effects. A gene might program some 'rule' into the individual (possibly hard wiring it into the brain), and from there it would not simply be "true relatedness", but a "best estimate" by the individual, resulting in a behavior.

From the outset, Dawkins stated he is "not advocating a morality based on evolution."[p. 2] Instead, he is simply describing what may have actually happened in evolution. Thus, we should expect selfishness in human nature, but must "teach generosity and altruism"[p. 3], although this does not mean that we will not observe altruism in nature. "Genes are the primary-policy makers; brains are the executives."[p. 60] Dawkins indicates that brains have evolved to take control of the body, even in opposition to the inherent selfish tendencies of replicators. Dawkins coined a term (meme) used as a 'unit of imitation', or of 'cultural inheritance'. Memes behave in similar ways that genes do - they selfishly compete to replicate themselves (memes compete for space in brains, genes compete for space on chromosomes). Dawkins relies, perhaps too much, on genetics. Human behavior is very complicated -- human social organization arises primarily through non-genetic, or cultural, means -- so social organization in humans may not be reducible to genetics. Dawkins indicates that through sexual reproduction, the number of (copies of original) genes diminish by 50% in each subsequent generation. Replicators are said to be theoretically immortal through copies. Replicators may behave selfishly, but if in reality they eventually disappear in subsequent generations, is it even necessary to describe individuals (as opposed to their genes) as inherently selfish? Replicators compete directly for space within an individual, and only consequently for existence in the gene or meme 'pool'. Selfishness then, is very useful in describing replicator behavior, but not necessarily an individual's behavior.

References:
Dawkins, R. (1976) The Selfish Gene. Oxford: Oxford University Press, reprinted in 1989.
Dawkins, R. (1998) Unweaving the Rainbow. New York: Houghton Mifflin Company.
Lorenz, K. (1963) On Aggression. San Diego: Harcourt Brace, reprinted in 1966.


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