Orthogenesis


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Related to Orthogenesis: Saltationism, orthogneiss

orthogenesis

[‚ȯr·thə′jen·ə·səs]
(evolution)
A unidirectional evolutionary change among a related group of animals.

Orthogenesis

 

the hypothesis that evolution proceeds directly toward higher adaptive states.

Orthogenesis is rooted in the views of J. B. Lamarck. The German scientists W. Haacke, who introduced the term “orthogenesis,” and G. H. T. Eimer, who used this term extensively, proceeded from the mechanistic Lamarckian position that the direction of evolution is controlled by the immediate influence of the environment and that the internal organization of an individual can change only in certain set directions. Subsequently, “orthogenesis” was often used to describe evolution as being controlled by an internal driving force as well as by the immediate influence of the environment.

Modern evolutionary theory, according to which the direction of evolution is a result of natural selection, usually contradicts the concept of orthogenesis. Although linearity is a feature of evolutionary change, modern theory attributes it to limitations imposed on the structural features of the organism; linearity essentially is the result of natural selection in past generations. (See AUTOGENESIS, LAMARCKISM.)

REFERENCES

Simpson, G. G. Tempy i formy evoliutsii. Moscow, 1948. (Translated from English.)
Shmal’gauzen, I. I. Problemy darvinizma, 2nd ed. Leningrad, 1969.
Haacke, W. Gestaltung und Vererbung, Leipzig, 1893.
Eimer, G. H. T. Die Entstehung der Arten. part 2: Die Orthogenesis der Schmetterlinge. Leipzig, 1897.

A. V. IABLOKOV

References in periodicals archive ?
24) This concept that the alpha is already part of the omega is explained by Pierre Teilhard de Chardin in his discussion of orthogenesis.
Much of the successful popular argument against original Darwinian Evolution is that it seems to imply a Victorian idea of Orthogenesis, where species progress "upward" through time, from primitive to complex, in a natural order.
But there are two crucial distinctions that Williams fails to make: a) Darwinian gradualism is only one of a panoply of naturalistic explanations of evolution (others include Lamarckism, orthogenesis, and saltationism); while it is indeed the one currently most widely accepted by scientists, it is false to charge that it is the only game in town and is therefore accepted by default.
Appleman discusses the new, old trend called intelligent design, which is merely fiat creationism allowing for more geologic time but still beholden to orthogenesis (with God calling the shots).
Orthogenesis, whose chief spokesman was German zoologist Theodor Eimer, held that an evolving species followed an internally directed path of change that had nothing to do with adaptation.
Orthogenesis is a term first used by the biologist Wilhelm Haacke in 1893 and later defined by Gustav Eimer as a general law by which evolution takes place in a noticeable direction.
Thus, Salkever notes that "Aristotle's biology does not result in a theory of orthogenesis, or a kind of theodicy which bestows the blessings of the gods on a particular group of humans" (1986, 238).
Even if one were able to get along without miracles, there would still be a fundamental difference between orthogenesis and Darwinian evolution, insofar as the reality of change is concerned.
Orthogenesis describes "evolution consistently directed along a single path by forces originating within the organisms themselves.