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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| History of paleontology | 6/10 | https://en.wikipedia.org/wiki/History_of_paleontology | reference | science, encyclopedia | 2026-05-05T04:00:05.779726+00:00 | kb-cron |
In 1808, Cuvier identified a fossil found in Maastricht as a giant marine reptile that would later be named Mosasaurus. He also identified, from a drawing, another fossil found in Bavaria as a flying reptile and named it Pterodactylus. He speculated, based on the strata in which these fossils were found, that large reptiles had lived prior to what he was calling "the age of mammals". Cuvier's speculation would be supported by a series of finds that would be made in Great Britain over the course of the next two decades. Mary Anning, a professional fossil collector since age eleven, collected the fossils of a number of marine reptiles and prehistoric fish from the Jurassic marine strata at Lyme Regis. These included the first ichthyosaur skeleton to be recognized as such, which was collected in 1811, and the first two plesiosaur skeletons ever found in 1821 and 1823. Mary Anning was only 12 when she and her brother discovered the Ichthyosaurus skeleton. Many of her discoveries would be described scientifically by the geologists William Conybeare, Henry De la Beche, and William Buckland. It was Anning who observed that stony objects known as "bezoar stones" were often found in the abdominal region of ichthyosaur skeletons, and she noted that if such stones were broken open they often contained fossilized fish bones and scales as well as sometimes bones from small ichthyosaurs. This led her to suggest to Buckland that they were fossilized feces, which he named coprolites, and which he used to better understand ancient food chains. Mary Anning made many fossil discoveries that revolutionized science. However, despite her phenomenal scientific contributions, she was rarely recognized officially for her discoveries. Her discoveries were often credited to wealthy men who bought her fossils. In 1824, Buckland found and described a lower jaw from Jurassic deposits from Stonesfield. He determined that the bone belonged to a carnivorous land-dwelling reptile he called Megalosaurus. That same year Gideon Mantell realized that some large teeth he had found in 1822, in Cretaceous rocks from Tilgate, belonged to a giant herbivorous land-dwelling reptile. He called it Iguanodon, because the teeth resembled those of an iguana. All of this led Mantell to publish an influential paper in 1831 entitled "The Age of Reptiles" in which he summarized the evidence for there having been an extended time during which the earth had teemed with large reptiles, and he divided that era, based in what rock strata different types of reptiles first appeared, into three intervals that anticipated the modern periods of the Triassic, Jurassic, and Cretaceous. In 1832 Mantell would find, in Tilgate, a partial skeleton of an armored reptile he would call Hylaeosaurus. In 1841 the English anatomist Richard Owen would create a new order of reptiles, which he called Dinosauria, for Megalosaurus, Iguanodon, and Hylaeosaurus.
This evidence that giant reptiles had lived on Earth in the past caused great excitement in scientific circles, and even among some segments of the general public. Buckland did describe the jaw of a small primitive mammal, Phascolotherium, that was found in the same strata as Megalosaurus. This discovery, known as the Stonesfield mammal, was a much discussed anomaly. Cuvier at first thought it was a marsupial, but Buckland later realized it was a primitive placental mammal. Due to its small size and primitive nature, Buckland did not believe it invalidated the overall pattern of an age of reptiles, when the largest and most conspicuous animals had been reptiles rather than mammals.
=== Catastrophism, uniformitarianism and the fossil record === In Cuvier's landmark 1796 paper on living and fossil elephants, he referred to a single catastrophe that destroyed life to be replaced by the current forms. As a result of his studies of extinct mammals, he realized that animals such as Palaeotherium and Anoplotherium had lived before the time of the mammoths, which led him to write in terms of multiple geological catastrophes that had wiped out a series of successive faunas. By 1830, a scientific consensus had formed around his ideas as a result of paleobotany and the dinosaur and marine reptile discoveries in Britain. In Great Britain, where natural theology was very influential in the early 19th century, a group of geologists that included Buckland, and Robert Jameson insisted on explicitly linking the most recent of Cuvier's catastrophes to the biblical flood. Catastrophism had a religious overtone in Britain that was absent elsewhere. Partly in response to what he saw as unsound and unscientific speculations by William Buckland and other practitioners of flood geology, Charles Lyell advocated the geological theory of uniformitarianism in his influential work Principles of Geology. Lyell amassed evidence, both from his own field research and the work of others, that most geological features could be explained by the slow action of present-day forces, such as vulcanism, earthquakes, erosion, and sedimentation rather than past catastrophic events. Lyell also claimed that the apparent evidence for catastrophic changes in the fossil record, and even the appearance of directional succession in the history of life, were illusions caused by imperfections in that record. For instance he argued that the absence of birds and mammals from the earliest fossil strata was merely an imperfection in the fossil record attributable to the fact that marine organisms were more easily fossilized. Also Lyell pointed to the Stonesfield mammal as evidence that mammals had not necessarily been preceded by reptiles, and to the fact that certain Pleistocene strata showed a mixture of extinct and still surviving species, which he said showed that extinction occurred piecemeal rather than as a result of catastrophic events. Lyell was successful in convincing geologists of the idea that the geological features of the earth were largely due to the action of the same geologic forces that could be observed in the present day, acting over an extended period of time. He was not successful in gaining support for his view of the fossil record, which he believed did not support a theory of directional succession.