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:''See also Tree of life (disambiguation) for other meanings of the Tree of Life.'' The tree of life is a metaphor used to describe the relationships between organisms, both living and extinct. Its use dates back to at least the early 1800s. It was employed by Charles Darwin to express the concept of the branching divergence of varieties and then species in a process of common descent from ancestors. Ernst Haeckel coined the term phylogeny for the evolutionary relationships of species through time, and went further than Darwin in proposing phylogenic histories of life. The modern development of this idea is called the phylogenetic tree. ==Early trees of life== Although the mutability of species may have appeared in paintings〔Fausto Barbagli (2009) 'In Retrospect: The earliest picture of evolution?', ''Nature'' 19 November 2009〕 and trees have been used as a metaphor for other purposes (Porphyrian tree) earlier than 1800, the combination of the concept of branching evolution and the tree image did not appear before 1800. The earliest tree of life was published by the French botanist Augustin Augier in 1801. It shows the relationships between members of the plant kingdom. Jean-Baptiste Lamarck (1744–1829) produced the first branching tree of animals in his ''Philosophie Zoologique'' (1809). It was an upside-down tree starting with worms and ending with mammals. However, Lamarck did not believe in common descent of all life. Instead, he believed that life consists of separate parallel lines advancing from simple to complex.〔Peter J. Bowler (2003) 'Evolution. The History of an Idea', third edition, p.90-91.〕 The American geologist Edward Hitchcock (1793–1864) published in 1840 the first Tree of Life based on paleontology in his ''Elementary Geology''.〔J. David Archibald (2009) 'Edward Hitchcock’s Pre-Darwinian (1840) 'Tree of Life'.', ''Journal of the History of Biology'' (2009) 42:561–592〕 On the vertical axis are paleontological periods. Hitchcock made a separate tree for plants (left) and animals (right). The plant and the animal tree are not connected at the bottom of the chart. Furthermore, each tree starts with multiple origins. Hitchcock's tree was more realistic than Darwin's 1859 theoretical tree (see below) because Hitchcock used real names in his trees. It is also true that Hitchcock's trees were branching trees. However, they were not real ''evolutionary'' trees, because Hitchcock believed that a deity was the agent of change. That was an important difference with Darwin. The first edition of ''Vestiges of the Natural History of Creation'', which was published anonymously in 1844 in England, contained a tree like diagram (p. 212) in the chapter 'Hypothesis of the development of the vegetable and animal kingdoms'. It shows a model of embryological development where fish (F), reptiles (R), and birds (B) represent branches from a path leading to mammals (M). In the text this branching tree idea is tentatively applied to the history of life on earth: "there may be branching" (p. 191), but the branching diagram is not displayed again specifically for this purpose.〔See for (online edition of ''Vestiges'' ).〕 However, the image of a branching tree could easily have inspired others to use it explicitly as a representation of the history of life on earth. In 1858, a year before Darwin's ''Origin'', the paleontologist Heinrich Georg Bronn (1800–1862) published a hypothetical tree labeled with letters. Although not a creationist, Bronn did not propose a mechanism of change.〔J. David Archibald (2009) 'Edward Hitchcock’s Pre-Darwinian (1840) 'Tree of Life'.', ''Journal of the History of Biology'' (2009) page 568.〕 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「Tree of life (biology)」の詳細全文を読む スポンサード リンク
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