Portal:Sauropterygians/Sauropterygian articles

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The Cretaceous–Paleogene extinction event, often referred to as the Cretaceous–Tertiary extinction event, was the large-scale mass extinction of animal and plant species in a geologically short period of time, approximately 66 million years ago (mya). The K–Pg extinction event is associated with a geological signature, usually a thin band dated to that time and found in various parts of the world, known as the K–Pg boundary. K is the traditional abbreviation for the Cretaceous Period, and Pg is the abbreviation for the Paleogene Period. The event marks the end of the Mesozoic Era, and the beginning of the Cenozoic Era.

Non-avian dinosaur fossils are only found below the K–Pg boundary and became extinct immediately before or during the event. A very small number of dinosaur fossils have been found above the K-Pg boundary, but they have been explained as reworked, that is, fossils that have been eroded from their original locations then preserved in later sedimentary layers. Mosasaurs, plesiosaurs, pterosaurs and many species of plants and invertebrates also became extinct. Mammalian and bird clades passed through the boundary with few extinctions, and radiation from those Maastrichtian clades occurred well past the boundary. Rates of extinction and radiation varied across different clades of organisms.

Many scientists theorize that the Cretaceous–Paleogene extinctions were caused by one or more catastrophic geological events such as massive asteroid impacts or increased volcanic activity. Several impact craters and massive volcanic activity in the Deccan traps have been dated to the approximate time of the extinction event. These geological events may have reduced sunlight and hindered photosynthesis, leading to a massive disruption in Earth's ecology. Other researchers believe the extinction was more gradual, resulting from slower changes in sea level or climate. (see more...)

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Chicxulub Crater is an ancient impact crater buried underneath the Yucatán Peninsula, with its center located near the town of Chicxulub, Yucatán, Mexico. The crater is over 180 kilometers (110 mi) in diameter, making the feature one of the largest confirmed impact structures in the world; the asteroid or comet whose impact formed the crater was at least 10 km (6 mi) in diameter. The crater was named for the nearby town, as well as for the literal Maya translation of the name: "tail of the devil." The crater was discovered by Glen Penfield, a geophysicist who had been working in the Yucatán while looking for oil during the late 1970s. The presence of tektites, shocked quartz and gravity anomalies, as well as the age of the rocks and isotope analysis, show that this impact structure dates from the late Cretaceous Period, roughly 65 million years ago. The impact associated with the crater is implicated in causing the extinction of the dinosaurs as suggested by the Cretaceous–Paleogene boundary, although some critics disagree that the impact was the sole reason and also debate whether there was a single impact or whether the Chicxulub impactor was one of several that may have struck the Earth at around the same time. Recent evidence suggests that the impactor was a piece of a much larger asteroid which broke up in a collision more than 160 million years ago.(see more...)

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The Bone Wars is the name given to a period of intense fossil speculation and discovery during the Gilded Age of American history, marked by a heated rivalry between Edward Drinker Cope and Othniel Charles Marsh. The two paleontologists used underhanded methods to out-compete the other in the field, resorting to bribery, theft, and destruction of bones. The scientists also attacked each other in scientific publications, attempting to ruin the other's credibility and cut off his funding.

Originally colleagues who were civil to each other, Cope and Marsh became bitter enemies after several personal slights between them. Their pursuit of bones led them west to rich bone beds in Colorado, Nebraska, and Wyoming. From 1877 to 1892, both paleontologists used their wealth and influence to finance their own expeditions and to procure services and fossils from dinosaur hunters. By the end of the Bone Wars, both men exhausted their funds in fueling their intense rivalry.

Cope and Marsh were financially and socially ruined by their efforts to disgrace each other, but their contributions to science and the field of paleontology were massive; the scientists left behind tons of unopened boxes of fossils on their deaths. The feud between the two men led to over 142 new species of dinosaurs being discovered and described. The products of the Bone Wars resulted in an increase in knowledge of ancient life, and sparked the public's interest in dinosaurs, leading to continued fossil excavation in North America in the decades to come. Several historical books and fictional adaptations have also been published about this period of intense paleontological activity. (see more...)

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Bone Sharps, Cowboys, and Thunder Lizards is a graphic novel written by Jim Ottaviani and illustrated by the company Big Time Attic. The book tells a slightly fictionalized account of the Bone Wars, a period of intense excavation, speculation, and rivalry which led to a greater understanding of dinosaurs in the western United States. This novel is the first semi-fictional work written by Ottaviani; previously, he had taken no creative license with the characters he depicted, portraying them strictly according to historical sources.

Bone Sharps follows the two scientists Edward Drinker Cope and Othniel Marsh as they engage in an intense rivalry for prestige. Ottaviani has Cope and Marsh interact and meet many important figures of the Gilded Age, from P. T. Barnum to U.S. Grant, as the two scientists pursue their hotheaded and sometimes illegal acquisitions of fossils. Unlike in his previous books, "the scientists are the bad guys this time". Upon release, the novel received praise from critics for its exceptional historical content, although some reviewers wished more fiction had been woven into the story. (see more...)

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Edward Drinker Cope (July 28, 1840 – April 12, 1897) was an American paleontologist and comparative anatomist, as well as a noted herpetologist and ichthyologist. Cope distinguished himself as a child prodigy, publishing his first scientific paper at the age of nineteen. Cope later married and moved from Philadelphia to Haddonfield, New Jersey, although Cope would maintain a residence and museum in Philadelphia in his later years.

Cope had little formal scientific training, and he eschewed a teaching position for field work. He made regular trips to the American West prospecting in the 1870s and 1880s, often as a member of United States Geological Survey teams. A personal feud between Cope and paleontologist Othniel Charles Marsh led to a period of intense fossil-finding competition now known as the Bone Wars. Cope's financial fortunes soured after failed mining ventures in the 1880s. He experienced a resurgence in his career toward the end of his life before dying in 1897.

Cope's scientific pursuits nearly bankrupted him, but his contributions helped to define the field of American paleontology. He was a prodigious writer, with 1,400 papers published over his lifetime, although his rivals would debate the accuracy of his rapidly published works. He discovered, described, and named more than 1,000 vertebrate species including hundreds of fishes and dozens of dinosaurs. His proposals on the origin of mammalian molars and for the gradual enlargement of mammalian species over geologic time ("Cope's Law") are notable among his theoretical contributions. (see more...)

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The Plesiosaurus sculpture from the "Dinosaur" Court

The Crystal Palace Dinosaurs, also known as Dinosaur Court, are a series of sculptures of extinct animals (including dinosaurs) and mammals in Crystal Palace Park, now in the London borough of Bromley. Commissioned in 1852 to accompany the Crystal Palace after its move from the Great Exhibition in Hyde Park and unveiled in 1854, they were the first dinosaur sculptures in the world, pre-dating the publication of Charles Darwin's On the Origin of Species by six years. While to varying degrees inaccurate by modern standards, the models were designed and sculpted by Benjamin Waterhouse Hawkins under the scientific direction of Sir Richard Owen, representing the latest scientific knowledge at the time. The models were classed as Grade II listed buildings from 1973, extensively restored in 2002, and upgraded to Grade I listed in 2007. The models represent fifteen genera of extinct animals, not all dinosaurs. They are from a wide range of geological ages, and include true dinosaurs, ichthyosaurs, and plesiosaurs mainly from the Mesozoic era, and some mammals from the more recent Cenozoic era. (see more...)

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Mary Anning (1799 – 1847) was a British fossil collector, dealer, and palaeontologist who became known around the world for important finds she made in Jurassic marine fossil beds in the cliffs along the English Channel at Lyme Regis in the county of Dorset in Southwest England. Her work contributed to fundamental changes in scientific thinking about prehistoric life and the history of the Earth.

Mary Anning searched for fossils in the area's Blue Lias cliffs. Her discoveries included the first ichthyosaur skeleton correctly identified; the first two plesiosaur skeletons found; the first pterosaur skeleton located outside Germany; and important fish fossils. Her observations played a key role in the discovery that coprolites, known as bezoar stones at the time, were fossilised faeces. She also discovered that belemnite fossils contained fossilised ink sacs like those of modern cephalopods.

Anning did not fully participate in the scientific community of 19th-century Britain, who were mostly Anglican gentlemen. She struggled financially for much of her life. Her family was poor, and her father, a cabinetmaker, died when she was eleven. She became well known in geological circles in Britain, Europe, and America. Nonetheless, as a woman, she was not eligible to join the Geological Society of London and she did not always receive full credit for her scientific contributions. After her death in 1847, her unusual life story attracted increasing interest. (see more...)

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