SALTATION (BIOLOGY)

In biology, 'saltation' (from Latin, ''saltus'', "leap") is a sudden change from one generation to the next, that is large, or very large, in comparison with the usual variation of an organism. The term is used for occasionally hypothesized, nongradual changes (especially single-step speciation) that are atypical of, or violate, standard concepts involved in neo-Darwinian evolution. The unorthodox emphasis on saltation as a means of evolutionary change is called 'saltationism'.
Saltation defies the orthodoxy of evolutionary theory, but there are some prominent proponents, including Carl Woese. Polyploidy (most common in plants but not unknown in animals) can be seen as a type of saltation. Polyploidy meets the basic criterea of saltation in that a significant change (in gene numbers) results in speciation in just one generation.
It's a popular misconception that punctuated equilibrium is a saltationist theory, often mistaken for Richard Goldschmidt's hypothesis of "Hopeful Monsters." However, punctuated equilibrium refers instead to a pattern of evolution where most speciation occurs relatively rapidly from a geological perspective (tens of thousands of years instead of millions of years), but through neo-Darwinian evolution, not by saltations.
In popular culture, a form of saltation appears to have emerged from misconceptions over currently accepted theories of evolution (the X-men and it's various spin-offs being the most egregious examples).

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See also

See also

★ Catastrophism

★ Hopeful Monster

★ Phyletic gradualism

★ Punctuated equilibrium

★ Rapid modes of evolution