Lamarckism

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A largely discredited evolutionary theory embodying the ideas of the French biologist J.B. de Lamarck (1774–1829). He proposed a comprehensive theory claiming that evolution proceeds by the inheritance of gradually acquired characters. He supposed that the use or lack of use of a body structure eventually leads to reinforcement or lapse of that trait by strive and direct environmental influence. The giraffes stretched their neck to reach the treetops, thus the inner drive and the circumstances contributed to their familiar shape. Contrarily, the current concepts, the neodarwinian theory believes that the longer-necked animals could feed better and thus, through continuous selection of increased neck length, their progeny had a selective advantage and facilitated the propagation of cumulative mutations that assured the survival of the best adapted genotypes. Neo-Lamarckism is basically an identical dogma to Lamarckism, except it emphasizes the use or disuse idea rather than the inner dr ...