User:Abyssal/Portal:Permian

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Selected article on the Permian world and its legacies

The annelids are a large phylum of segmented worms, with over 2,000 modern species including ragworms, earthworms and leeches. They are found in marine environments from tidal zones to hydrothermal vents, in freshwater, and in moist terrestrial environments. The basic annelid form consists of multiple segments, each of which has the same sets of organs and, in most polychaetes, a pair of parapodia that many species use for locomotion. Septa separate the segments of many species, but are poorly defined or absent in some. Septa also enable annelids to change the shapes of individual segments, which facilitates movement by "ripples" that pass along the body or by undulations. Although many species can reproduce asexually and use similar mechanisms to regenerate after severe injuries, sexual reproduction is the normal method in species whose reproduction has been studied.

Since annelids are soft-bodied, their fossils are rare – mostly jaws and the mineralized tubes that some of the species secreted. Although some late Ediacaran fossils may represent annelids, the oldest known fossil that is identified with confidence comes from about 518 million years ago in the early Cambrian period. Fossils of most modern mobile polychaete groups appeared by the end of the Carboniferous, about 299 million years ago. Scientists disagree about whether some body fossils from the mid Ordovician, about 472 to 461 million years ago, are the remains of oligochaetes, and the earliest certain fossils of the group appear in the Tertiary period, which began 65 million years ago. (see more...)

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Restoration of Tiarajudens.
Restoration of Tiarajudens.

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Skeletal mount of Casea.

Skeletal mount of Casea.
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Selected article on the Permian in human science, culture and economics

Edward Drinker Cope (left) and Othniel Charles Marsh (right).
Edward Drinker Cope (left) and Othniel Charles Marsh (right).
Bone Sharps, Cowboys, and Thunder Lizards: A Tale of Edward Drinker Cope, Othniel Charles Marsh, and the Gilded Age of Paleontology (2005) 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...)

Quality Content

Featured Permian articles - Amphibian
Good Permian articles - Dimetrodon - Temnospondyli

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