Evolutionary adoption hypothesis

Some authors assume that the relationship between a morphological trait that is useful from the viewpoint of specific behavior of an organism and the behavior itself is exactly the opposite of how it is described by the Baldwin effect. They assume that the relevant (incidental) phenotype change is primary and useful exploitation of the change by creating an appropriate behavioral pattern is secondary. Returning to the example in Chap. XVI.3.2, we find that birds with large strong beak first arise and that they then look for ways to use it and then, finally, by the trial-and-error method, they find that it can be used for shelling snails. According to these conceptions, in evolution,  the phenotype of organisms does not adapt itself to activities and the environment through adaptations, but rather by adoptions – by actively creating those behavioral patterns that best utilize the changes in the phenotype made by mutations and by seeking an environment where these phenotype changes can be best used (Piaget 1979; Ho & Saunders 1982).
            It may seem that both variants of the origin of usefulness are possible and even highly probable for adaptive traits that are conditioned by only one mutation. Actually, egression of the usefulness of adaptations by the Baldwin effect is much more probable. If a new mutation arises, e.g. one that leads to egression of a large strong beak, and the mutant would be lucky enough to find a way of using it sensibly, for example for cracking snails’ shells, it (the now useful mutation) can be passed on only to the organism’s offspring . However, it would be a prolonged and rather improbable process for the mutant’s offspring to prevail in population. Most – even very useful – mutations vanish from the population during a few generations because of genetic drift. If more mutations are required for the optimal value of the trait (the optimal beak size in our case), all of them have to appear in the offspring of the particular mutant. On the contrary, when the evolutionary novelty is made by the Baldwin effect, i.e. a particular behavior pattern is created first (birds start to crack the snails, even imperfectly because of a weak beak), this behavior pattern can spread horizontally into the whole population by imitation and the useful mutations (e.g. for a strong beak) can consequently arise in any individual. The speed and probability of development of evolutionary novelties by the Baldwin effect, i.e. by adapting the organisms to their environment and behavior through mutations, is much greater than if the organisms would have to look for an environment and behavior that would suit their mutations.

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The classical Darwinian theory of evolution can explain the evolution of adaptive traits only in asexual organisms. The frozen plasticity theory is much more general: It can also explain the origin and evolution of adaptive traits in both asexual and sexual organisms Read more