The existence and potential evolutionary importance of macromutations is an interesting and still-discussed aspect of evolutionary biology. Darwin’s theory of the development of living systems is based on gradual accumulation of micromutations, i.e. mutations that lead to slight changes in the phenotype of organisms. Only long-term accumulation of these minor changes, as a consequence of the consistent action of natural selection, can lead to major evolutionary changes in the structure of organisms. Darwinists assume that even very complicated structures like the eye or wing develop by this gradual accumulation of minor changes. On the other hand, some biologists, for example Richard B. Goldschmidtin the 1940’s and 1950’s (Goldschmidt 1998), were or are of the opinion that complicated structures and major changes in the body plan appear suddenly in evolution, in a sudden jump, as a consequence of “macromutations” (saltations, saltationism), which occur suddenly in some individuals in the population {9650}.

It is certain that mutations that can substantially affect the phenotype of an organism actually occur in the population with low frequency. These are mostly mutations in regulation genes and in genes that control the early stages of ontogenesis (Akam 1998). However, mostly these mutations lead to simplification of the body structure, to the loss of certain organs or, on the other hand, to a greater number of them or to replacement of one organ by another (antennae – legs in insects, etc.). In this sense, macromutations certainly exist. However, their evolutionary importance is rather questionable. We can imagine the formation of a basically new organ as the consequence of the accumulation of minor advantageous changes; on the other hand, the formation of a useful complex organ in a single large jump is a highly improbable event. However, even if such a change were to occur, the hopeful monster would probably encounter substantial difficulties in searching for an ecological niche and sexually reproducing organisms could find it difficult to find a sexual partner.

Some authors are of the opinion that, in addition to macromutations in the above-described sense, there are also other categories of macromutations. However, these would not be classical mutations with a large phenotype effect, but rather simultaneous changes at many sites in the genome, that would occur simultaneously, through a currently unknown, unspecified mechanism. A change in the structure of some tRNA could probably appear as such a change and this would cause that a certain aminoacid would be replaced by a different aminoacid in all the genes. As is already apparent from the above examples, the probability that such a drastic intervention in the genetic information could lead to the formation of a viable individual is quite small. The probability that a complicated adaptive structure could be formed in this way is probably zero.

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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