Saltation (biology)

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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.

Theories of Evolution

Based on Essentialism:
- Transmutationism (saltation)
- Transformationism
  - Orthogenesis
    - Lamarckism
  - Neo-Lamarckism
Based on Population biology:
- Darwinian evolution

Saltation is generally not held to be a method by which evolution occurs. However, 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 creation in 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.