N. N. Iordansky
A. N. Severtzov Institute of Ecology and Evolution, Russian Academy of Sciences
119071 Moscow, Leninsky pr., 33
e-mail: niordansky@yandex.ru
The term saltation is a composite notion covering different categories of supposed saltational evolutionary changes. One can distinguish interspecies, macroevolutionary and morphofunctional saltations corresponding to saltational arising of a new species, of general Bauplans of new macrotaxons, and of large-scale morphofunctional alterations (irrelevant to any taxonomic aspects). Current data confirm the possibility of interspecies and mophofunctional saltations as relatively rare modes of evolutionary changes. Morphofunctional saltations result in the arising of macromorphoses that can sometimes stimulate the beginning of macroevolutionary typogenesis. Saltationism extremely exaggerates the evolutionary role of saltations, considering these to be the main factor of speciation and macroevolution. However, saltations are only peculiar and relatively rare form of hereditary variability representing elementary evolutionary material. Natural selection is the principal evolutionary mechanism that produces new adaptations and integrates different systems of the organism in the process of typogenesis. The arising of general Bauplans of new macrotax by means of macroevolutionary saltations seems to be improbable.
