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Neo-Darwinism is the "modern synthesis" of Darwinian evolution through natural selection with Mendelian genetics, the latter being a set of primary tenets specifying that evolution involves the transmission of characteristics from parent to offspring through the mechanism of genetic transfer, rather than the "blending process" of pre-Mendelian evolutionary science. Neo-Darwinism can also designate Charles Darwin's ideas of natural selection separated from his hypothesis of pangenesis as a Lamarckian source of variation involving blending inheritance. As part of the disagreement about whether natural selection alone was sufficient to explain speciation, George Romanes coined the term ''neo-Darwinism'' in 1895 to refer to the version of evolution advocated by Alfred Russel Wallace and August Weismann with its heavy dependence on natural selection. Weismann and Wallace rejected the Lamarckian idea of inheritance of acquired characteristics that even Darwin took for granted. The term was first used to explain that evolution occurs solely through natural selection, and not by the inheritance of acquired characteristics resulting from use or disuse. The basis for the complete rejection of Lamarckism was Weismann's germ plasm theory. Weismann realised that the cells that produce the germ plasm, or gametes (such as sperm and egg in animals), separate from the somatic cells that go on to make other body tissues at an early stage in development. Since he could see no obvious means of communication between the two, he asserted that the inheritance of acquired characteristics was therefore impossible; a conclusion now known as the Weismann barrier. From the 1880s to the 1930s, the term continued to be applied to the panselectionist school of thought, which argued that natural selection was the main and perhaps sole cause of all evolution. From then until around 1947, the term was used for the panselectionist followers of Ronald Fisher. ==Modern evolutionary synthesis== Following the development, from about 1936 to 1947, of the modern evolutionary synthesis, now generally referred to as the ''synthetic view of evolution'' or the ''modern synthesis'', the term neo-Darwinian is often used to refer to contemporary evolutionary theory. However, some have described such usage as incorrect;〔〔 with Ernst Mayr writing in 1984 that "the term neo-Darwinism for the synthetic theory is wrong, because the term neo-Darwinism was coined by Romanes in 1895 as a designation of Weismann's theory."〔 Volume Two: Symposia and Invited Papers (1984).〕 Despite such objections, publications such as ''Encyclopædia Britannica'' use this term to refer to current evolutionary theory. Richard Dawkins and Stephen Jay Gould use the term in their writings and lectures.〔. The video of the lecture was originally posted on May 5, 2010, at old.richarddawkins.net: .〕 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「Neo-Darwinism」の詳細全文を読む スポンサード リンク
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