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III - Evolution and Adaptation
Waddington ( 1942 ) writes about
the dispute at his time between naturalists and geneticists highlighting the prominence of genetics as a theory based on evidence . The central argument developed by Waddington is that adaptations may occur as answers to the environment , but that the genetic factor finally surpasses the initial environment effect . In fact , he claims adaptation is only possible because the answer itself is already genetically programmed and is only ‘ activated ’ by the environment . Further , he adds that canalization also supports genetics . Waddington defines canalization as : “[ developmental reactions that ] are adjusted so as to bring about one definite end-result regardless of minor variations in conditions ” ( Waddington , 1942 , p . 563 ). Waddington makes clear the idea that a channel is a conveyor of alternatives that are activated or not depending on the influence of the environment or other correlated processes that work as switches .
… the occurrence of an adaptive response to an environmental stimulus depends on the selection of a suitable genetically controlled reactivity in the organism . If it is an advantage … then the reactivity will become canalized , again under the influence of natural selection . ( Waddington , 1942 , p . 565 )
On a rather different focus on biological systems , Raup ( 1966 ) exploits the evolution of complex life through the study of the geometry of shells that grow in spirals . He postulates that the format of shells can be expressed by geometric parameters and simulates computationally the formats that could exist theoretically . The comparison of the simulation with real species shows that the known species in nature are not randomly distributed within all possible formats . On the contrary , they concentrate on discrete regions of the distribution . Raup suggests that there are rational explanations for this distribution which could be potentially associated to the functional characteristics of the shells . His work is an example of the evolutionary exploitation of the morphospace and of the use of computational simulation to study the growth and form of organisms .
Kauffman makes early contributions in biology , specifically discussing the origins of molecular reproduction ( Kauffman , 1969 , 1971 ), and conceptualizing the idea of self-organization and self-organizing critically ( Kauffman , 199� ; Kauffman , 199� ).
Maynard Smith ( 1974 ), in turn , applies Game Theory to analyze the evolution of patterns of behavior in conflicts among animals and establishes the concept of Evolutionary Stable Strategy ( ESS ). A strategy I is considered ESS , if the expected utility of a player using strategy I against himself is higher than the expected utility of strategy J applied against strategy I .
E I
( I )> E I
( J ) ,
where E indicates the expectancy of the utility of the strategy in parenthesis against the other strategy .
In a population composed of individuals who adopt strategy I , initially rare mutant individuals , adopting a strategy J different from I would not increase in frequency so that the population would remain stable even with the occurrence of mutation and natural selection . The ESS can be said to have contributed greatly to the study of Evolution .
Holland and Reitman ( 1977 ) feed on ideas of evolution and apply them to computing . They propose the use of simple learning genetic algorithms that can ( a )
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