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The inheritance of acquired characteristics is a hypothesis that physiological changes acquired over the life of an organism (such as the enlargement of a muscle through repeated use) may be transmitted to offspring.〔Martin, Elizabeth; Hine, Robert. (2015). ''A Dictionary of Biology''. Oxford University Press. p. 6. ISBN 978-0-19-871437-8〕 It is also commonly referred to as the theory of adaptation equated with the evolutionary theory of French naturalist Jean-Baptiste Lamarck known as ''Lamarckism''. ==History== The idea was proposed in ancient times by Hippocrates and Aristotle, and was commonly accepted near to Lamarck's time. Erasmus Darwin had described the inheritance of acquired characters in his ''Zoonomia'', 1794. According to historian of science Conway Zirkle: Lamarck was neither the first nor the most distinguished biologist to believe in the inheritance of acquired characters. He merely endorsed a belief which had been generally accepted for at least 2,200 years before his time and used it to explain how evolution could have taken place. The inheritance of acquired characters had been accepted previously by Hippocrates, Aristotle, Galen (?), Roger Bacon, Jerome Cardan, Levinus Lemnius, John Ray, Michael Adanson, Jo. Fried. Blumenbach and Erasmus Darwin among others.〔Zirkle, Conway. (1935). ''The Inheritance of Acquired Characters and the Provisional Hypothesis of Pangenesis''. ''The American Naturalist'' 69: 417-445.〕 Lamarck published his theory in 1809, the year Darwin was born. He noticed several lines of descent by comparing current species with fossil forms. He noticed that the younger the fossils were, the more alike they were to modern species. Two ideas were incorporated in Lamarck’s theory. The first was the theory of use and disuse; the idea that body parts used more often become stronger and larger, while parts not used slowly waste away and disappear. The second idea was the inheritance of acquired characteristics theory, the concept that modifications that occur during an organism's lifetime are passed on to its offspring. His example was the giraffe. He believed that the long neck of the giraffe resulted from the ancestors of giraffes stretching their necks longer and longer while trying to reach the highest branches of the trees.〔 〕 Comte de Buffon, before Lamarck, proposed ideas about evolution involving the concept, and even Charles Darwin, after Lamarck, developed his own theory of inheritance of acquired characters, pangenesis. The basic concept of inheritance of acquired characters was finally widely rejected in the early 20th century. In the 1920s, Harvard University researcher William McDougall studied the abilities of rats to correctly solve mazes. His reports claimed that offspring of rats that had learned the maze were able to run it faster. In his data, the first rats would get it wrong 165 times before being able to run it perfectly each time, but after a few generations, it was down to 20. McDougall attributed this to some sort of Lamarckian evolutionary process. However McDougall's results have never been replicated by other experimenters, and have been criticised for having several methodological problems and poor record-keeping. During the rule of Joseph Stalin in the USSR in the 1930s, the theory of inheritance of acquired characteristics was central to the dogma put forth by Trofim Lysenko, president of the Soviet Academy of Agricultural Sciences. Lysenkoism was advanced primarily in service to Soviet agriculture, always resulting in dismal failure. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Inheritance of acquired characteristics」の詳細全文を読む スポンサード リンク
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