Saltationist evolution

- The punctualist model of evolution has sometimes erroneously been confused with the models of saltationist evolution, i.e. models that assume the existence of typostrophic saltation – sudden instantaneous phenotype changes of major extent. According to saltationists, all important evolutionary changes occur in jumps, basically from one generation to the next. The mechanism of the relevant changes leading to the particular evolutionary jump mostly includes macromutation, a genetic change with major phenotype impact. For example, some mutations in the genes controlling the progress of the early stages of ontogenesis could be considered to be macromutations. This type of mutation, leading to the instantaneous formation of hopeful monsters, could be feasible in the emergence of biological diversity and especially disparities and could thus occur in the evolution of some large taxa that substantially differ in the basic organization of their body structure and thus in the formation of the individual strains. However, it could not be very important for the evolution of adaptive traits, as it is highly improbable that a random change of major extent could increase the functionality of a complicated organism. The vast majority of evolutionary changes occurred through the gradual accumulation of mutations with minor impact.
            However, the punctualist model of evolution, similar to the gradualist model, does not require the participation of sudden phenotype changes, saltations. The time during which evolution occurs according to punctualists is of the order of tens of thousands of years; this is a very short time on the scale employed by paleontologists; however, from the viewpoint of the usual rate of microevolution, this is quite adequate for the gradual accumulation of normal mutations to collect a sufficient number of anagenetic changes that would be quite sufficient for the formation of a new species. Thus, it is erroneous to confuse the punctualist model with the saltationist model.

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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