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The history of paleontology traces the history of the effort to understand the history of life on Earth by studying the fossil record left behind by living organisms. Since it is concerned with understanding living organisms of the past paleontology can be considered to be a field of biology, but its historical development has been closely tied to geology and the effort to understand the history of the Earth itself. In ancient times Xenophanes (570-480 BC), Herodotus (484-425 BC), Eratosthenes (276-194 BC), and Strabo (64 BC-24 AD), wrote about fossils of marine organisms indicating that land was once under water. During the Middle Ages, fossils were discussed by the Persian naturalist, Ibn Sina (known as ''Avicenna'' in Europe), in ''The Book of Healing'' (1027), which proposed a theory of petrifying fluids that Albert of Saxony would elaborate on in the 14th century. The Chinese naturalist Shen Kuo (1031–1095) would propose a theory of climate change based on evidence from petrified bamboo. In early modern Europe, the systematic study of fossils emerged as an integral part of the changes in natural philosophy that occurred during the Age of Reason. The nature of fossils and their relationship to life in the past became better understood during the 17th and 18th centuries, and at the end of the 18th century the work of Georges Cuvier ended a long running debate about the reality of extinction and led to the emergence of paleontology, in association with comparative anatomy, as a scientific discipline. The expanding knowledge of the fossil record also played an increasing role in the development of geology, particularly stratigraphy. In 1822 the word "paleontology" was invented by the editor of a French scientific journal to refer to the study of ancient living organisms through fossils, and the first half of the 19th century saw geological and paleontological activity become increasingly well organized with the growth of geologic societies and museums and an increasing number of professional geologists and fossil specialists. This contributed to a rapid increase in knowledge about the history of life on Earth, and progress towards definition of the geologic time scale largely based on fossil evidence. As knowledge of life's history continued to improve, it became increasingly obvious that there had been some kind of successive order to the development of life. This would encourage early evolutionary theories on the transmutation of species. After Charles Darwin published ''Origin of Species'' in 1859, much of the focus of paleontology shifted to understanding evolutionary paths, including human evolution, and evolutionary theory.〔 The last half of the 19th century saw a tremendous expansion in paleontological activity, especially in North America.〔 The trend continued in the 20th century with additional regions of the Earth being opened to systematic fossil collection, as demonstrated by a series of important discoveries in China near the end of the 20th century. Many transitional fossils have been discovered, and there is now considered to be abundant evidence of how all classes of vertebrates are related, much of it in the form of transitional fossils. The last few decades of the 20th century saw a renewed interest in mass extinctions and their role in the evolution of life on Earth.〔Bowler Evolution: The History of an Idea pp. 351-352〕 There was also a renewed interest in the Cambrian explosion that saw the development of the body plans of most animal phyla. The discovery of fossils of the Ediacaran biota and developments in paleobiology extended knowledge about the history of life back far before the Cambrian. ==Prior to the 17th century== As early as the 6th century BC, the Greek philosopher Xenophanes of Colophon (570-480 BC) recognized that some fossil shells were remains of shellfish, which he used to argue that what was at the time dry land was once under the sea.〔Desmond p. 692-697.〕 Leonardo da Vinci (1452–1519), in an unpublished notebook, also concluded that some fossil sea shells were the remains of shellfish. However, in both cases, the fossils were complete remains of shellfish species that closely resembled living species, and were therefore easy to classify.〔Rudwick ''The Meaning of Fossils'' p. 39〕 In 1027, the Persian naturalist, Ibn Sina (known as ''Avicenna'' in Europe), proposed an explanation of how the stoniness of fossils was caused in ''The Book of Healing''.〔 He modified an idea of Aristotle's, which explained it in terms of vaporous exhalations. Ibn Sina modified this into the theory of petrifying fluids (''succus lapidificatus''), which was elaborated on by Albert of Saxony in the 14th century and was accepted in some form by most naturalists by the 16th century.〔Rudwick ''The Meaning of Fossils'' p. 24〕 Shen Kuo () (1031–1095) of the Song Dynasty used marine fossils found in the Taihang Mountains to infer the existence of geological processes such as geomorphology and the shifting of seashores over time.〔Shen Kuo,''Mengxi Bitan'' (梦溪笔谈; ''Dream Pool Essays'') (1088)〕 Using his observation of preserved petrified bamboos found underground in Yan'an, Shanbei region, Shaanxi province, he argued for a theory of gradual climate change, since Shaanxi was part of a dry climate zone that did not support a habitat for the growth of bamboos.〔Needham, Volume 3, p. 614.〕 As a result of a new emphasis on observing, classifying, and cataloging nature, 16th century natural philosophers in Europe began to establish extensive collections of fossil objects (as well as collections of plant and animal specimens), which were often stored in specially built cabinets to help organize them. Conrad Gesner published a 1565 work on fossils that contained one of the first detailed descriptions of such a cabinet and collection. The collection belonged to a member of the extensive network of correspondents that Gesner drew on for his works. Such informal correspondence networks among natural philosophers and collectors became increasingly important during the course of the 16th century and were direct forerunners of the scientific societies that would begin to form in the 17th century. These cabinet collections and correspondence networks played an important role in the development of natural philosophy.〔Rudwick ''The Meaning of Fossils'' pp. 9-17〕 However, most 16th-century Europeans did not recognize that fossils were the remains of living organisms. The etymology of the word ''fossil'' comes from the Latin for things having been dug up. As this indicates, the term was applied to wide variety of stone and stone-like objects without regard to whether they might have an organic origin. 16th-century writers such as Gesner and Georg Agricola were more interested in classifying such objects by their physical and mystical properties than they were in determining the objects' origins.〔Rudwick ''The Meaning of Fossils'' pp. 23-33〕 In addition, the natural philosophy of the period encouraged alternative explanations for the origin of fossils. Both the Aristotelian and Neoplatonic schools of philosophy provided support for the idea that stony objects might grow within the earth to resemble living things. Neoplatonic philosophy maintained that there could be affinities between living and non-living objects that could cause one to resemble the other. The Aristotelian school maintained that the seeds of living organisms could enter the ground and generate objects resembling those organisms.〔Rudwick ''The Meaning of Fossils'' pp. 33-36〕 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「history of paleontology」の詳細全文を読む スポンサード リンク
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