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  Lamarckism is a theory, proposed by the French naturalist Jean-Baptiste Lamarck in 1809, which suggested that evolution occurred as a result of beneficial characteristics, acquired by an individual during its life, being passed on to its offspring. Moreover, the individual acquires new characteristics and abilities as a result of effort to satisfy new challenges from the environment. Thus, for example, the giraffe has evolved a long neck as a result of stretching to reach high leaves, and the blacksmith\'s son will inherit his father\'s strong arms. Lamarck\'s ideas were entirely hypothetical, but, though recognized as such, they influenced many 19th-century scientists, including Darwin. By the early 20th century Lamarckism was largely discredited but was perpetuated in the USSR by the influential biologist Trofim Lysenko who denied the existence of genes. Lysenkoism was officially endorsed because it appeared to corroborate the socialist ideals of equality, and between the 1930s and the 1960s many of its opponents were ‘executed’, to the great detriment of Soviet science.

Neo-Lamarckism allows the idea that natural selection may act upon the acquired characteristics of an individual. However, Lamarckist doctrine is entirely contradicted by molecular biology, which states that information encoded in genes can pass to gene products but that this information flow is unidirectional. RB

See also pangenesis.Further reading Arthur Koestler, The Case of the Midwife Toad.



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