Neo-Lamarckism (redirected from neo-Lamarckian)

Neo-Lamarckism 

a movement in evolutionary theory that arose during the second half of the 19th century and claimed to be an elaboration of certain tenets of Lamarckism. Most representatives of neo-Lamarckism diverged substantially from—or completely distorted—Lamarck’s teachings.

All neo-Lamarckian viewpoints acknowledge the heritability of acquired traits and reject the morphogenetic role of natural selection. Three main trends can be distinguished: mechano-Lamarckism, ortho-Lamarckism, and neovitalism. Mechano-Lamarckism as advocated by the British scientist H. Spencer, the German T. Eimer, and the Frenchmen G. Bonnier and A. Giard ascribes a dominant role in evolution to environmental conditions and considers morphogenesis to occur only on the level of each individual organism. The significance of the term “evolutionary process” is limited to the accumulation of adaptive changes occurring simultaneously in all individuals of a population in response to environmental factors.

Orthogenetic trends maintain that development is motivated by certain internal properties in an organism that appear to predetermine straight-line evolution. This viewpoint was held by several scientists, including the German K. W. Von Nägeli, the Americans H. Osborn and E. Cope, and the Soviet scientist L. S. Berg. Neovitalism considers the main source of evolution to lie in the conscious volitional acts of organisms. Advocates of this theory include the German scientists A. Pauli, R. France, and A. Wagner. Neovitalists endow with consciousness and memory not only the entire animal or plant but also the individual cells that these larger entities comprise.

Modern forms of neo-Lamarckism persist despite their scientific untenability.

REFERENCES

Delage, Y., and M. I. Goldsmith. Teorii evoliutsii. St. Petersburg, 1916. (Translated from French.)
Istoriia evoliutsionnykh uchenii v biologii. Moscow-Leningrad, 1966.
Fothergill, P. G. Historical Aspects of Organic Evolution. New York, 1953.
Rostand, J. Esquisse d’une histoire de la biologie. Paris, 1964.

V. I. NAZAROV