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Graptolites
Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian (Miaolingian, Wuliuan) through the Lower Carboniferous ( Mississippian). A possible early graptolite, ''Chaunograptus'', is known from the Middle Cambrian. Recent analyses have favored the idea that the living pterobranch '' Rhabdopleura'' represents an extant graptolite which diverged from the rest of the group in the Cambrian. Fossil graptolites and ''Rhabdopleura'' share a colony structure of interconnected zooids housed in organic tubes (theca) which have a basic structure of stacked half-rings (fuselli). Most extinct graptolites belong to two major orders: the bush-like sessile Dendroidea and the planktonic, free-floating Graptoloidea. These orders most likely evolved from encrusting pterobranchs similar to ''Rhabdopleura''. Due to their widespread abundance, pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordovician
The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years from the end of the Cambrian Period Megaannum, Ma (million years ago) to the start of the Silurian Period Ma. The Ordovician, named after the Celtic Britons, Welsh tribe of the Ordovices, was defined by Charles Lapworth in 1879 to resolve a dispute between followers of Adam Sedgwick and Roderick Murchison, who were placing the same Rock (geology), rock beds in North Wales in the Cambrian and Silurian systems, respectively. Lapworth recognized that the fossil fauna in the disputed Stratum, strata were different from those of either the Cambrian or the Silurian systems, and placed them in a system of their own. The Ordovician received international approval in 1960 (forty years after Lapworth's death), when it was adopted as an official per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclograptidae
Cyclograptidae is an extinct family of graptolite Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian ( Miaolingian, Wuliuan) through t ...s. Genera List of genera from Maletz (2014): *? †'' Alternograptus'' Bouček, 1956 *? †'' Callodendrograptus'' Decker, 1945 *†'' Calycotubus'' Kozłowski, 1949 *†'' Camarotubus'' Mierzejewski, 2001 *†'' Conitubus'' Kozłowski, 1949 *†'' Cyclograptus'' Spencer, 1883 *†'' Dendrotubus'' Kozłowski, 1949 *†'' Discograptus'' Wiman, 1901 *†'' Dyadograptus'' Obut, 1960 *†'' Galeograptus'' Wiman, 1901 *†'' Kozlowskitubus'' Mierzejewski, 1978 *†'' Marsipograptus'' Ruedemann, 1936 *†'' Multitubus'' Skevington, 1963 *†'' Parvitubus'' Skevington, 1963 *†'' Reticulograptus'' Wiman, 1901 *†'' Rhiphidodendrum'' Kozłowski, 1949 *†'' Rodonograptus'' Počta, 1894 *� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cysticamaridae
Cysticamaridae is an extinct family of graptolite Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian ( Miaolingian, Wuliuan) through t ...s. Genera List of genera from Maletz (2014): *†'' Bithecocamara'' Kozłowski, 1949 *†'' Cysticamara'' Kozłowski, 1949 *†'' Erecticamara'' Mierzejewski, 2000 *†'' Flexicollicamara'' Kozłowski, 1949 *†'' Graptocamara'' Kozłowski, 1949 *†'' Syringataenia'' Obut, 1953 *†'' Tubicamara'' Kozłowski, 1949 References Graptolites Prehistoric hemichordate families {{Hemichordate-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wimanicrustidae
Wimanicrustidae is an extinct family of graptolite Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian ( Miaolingian, Wuliuan) through t ...s. Genera List of genera from Maletz (2014): *†'' Bulmanicrusta'' Kozłowski, 1962 *†'' Ellesicrusta'' Kozłowski, 1962 *†'' Graptoblastoides'' Kozłowski, 1949 *†'' Graptoblastus'' Kozłowski, 1949 *†'' Holmicrusta'' Kozłowski, 1962 *†'' Hormograptus'' Öpik, 1930 *†'' Lapworthicrusta'' Kozłowski, 1962 *†'' Maenniligraptus'' Mierzejewski, 1986b *†'' Ruedemannicrusta'' Kozłowski, 1962 *†'' Thallograptus'' Öpik, 1928 *†'' Urbanekicrusta'' Mierzejewski, 1986b *†'' Wimanicrusta'' Kozłowski, 1962 *†'' Xenocyathus'' Eisenack, 1982 References Graptolites Prehistoric hemichordate families {{Hemichordate-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dithecodendridae
Dithecodendridae is an extinct family of graptolite Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian ( Miaolingian, Wuliuan) through t ...s. Genera List of genera from Maletz (2014): *†'' Archaeolafoea'' Chapman, 1919 *†'' Bulmanidendrum'' Obut, 1974 *? †'' Dalyia'' Walcott, 1919 *†'' Dithecodendrum'' Obut, 1964 *†'' Karasidendrum'' Sennikov, 1998 *†'' Ovetograptus'' Sdzuy, 1974 *†'' Protodendrum'' Sennikov, 1998 *†'' Siberiodendrum'' Obut, 1964 *†'' Sibiriograptus'' Obut, 1964 *†'' Sotograptus'' Sdzuy, 1974 *†'' Tarnagraptus'' Sdzuy, 1974 References Graptolites Prehistoric hemichordate families {{Hemichordate-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaunograptus
''Chaunograptus'' is a genus of putative graptolite known from the Middle Cambrian The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordov ... Burgess Shale. 11 specimens of ''Chaunograptus'' are known from the Greater Phyllopod bed, where they comprise 0.02% of the community. Species * ''Chaunograptus contortus'' * ''Chaunograptus gemmatus'' * ''Chaunograptus scandens'' References External links * Burgess Shale fossils Graptolite genera Cambrian genus extinctions {{cambrian-animal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sessility (motility)
Sessility is the biological property of an animal describing its lack of a means of self-locomotion. Sessile animals for which natural ''motility'' is absent are normally immobile. This is distinct from the botanical concept of sessility, which refers to an organism or biological structure attached directly by its base without a stalk. Sessile animals can move via external forces (such as water currents), but are usually permanently attached to something. Organisms such as corals lay down their own substrate from which they grow. Other organisms grow from a solid object, such as a rock, a dead tree trunk, or a human-made object such as a buoy or ship's hull. Mobility Sessile animals typically have a motile phase in their development. Sponges have a motile larval stage and become sessile at maturity. Conversely, many jellyfish develop as sessile polyps early in their life cycle. In the case of the cochineal, it is in the nymph stage (also called the crawler stage) that the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plankton
Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish, and baleen whales. Marine plankton include bacteria, archaea, algae, protozoa, microscopic fungi, and drifting or floating animals that inhabit the saltwater of oceans and the brackish waters of estuaries. fresh water, Freshwater plankton are similar to marine plankton, but are found in lakes and rivers. Mostly, plankton just drift where currents take them, though some, like jellyfish, swim slowly but not fast enough to generally overcome the influence of currents. Although plankton are usually thought of as inhabiting water, there are also airborne versions that live part of their lives drifting in the at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Index Fossils
Biostratigraphy is the branch of stratigraphy which focuses on correlating and assigning relative ages of rock strata by using the fossil assemblages contained within them.Hine, Robert. "Biostratigraphy." ''Oxford Reference: Dictionary of Biology'', 8th ed., Oxford University Press, 2019. The primary objective of biostratigraphy is ''correlation'', demonstrating that a particular horizon in one geological section represents the same period of time as another horizon at a different section. Fossils within these strata are useful because sediments of the same age can look completely different, due to local variations in the sedimentary environment. For example, one section might have been made up of clays and marls, while another has more chalky limestones. However, if the fossil species recorded are similar, the two sediments are likely to have been laid down around the same time. Ideally these fossils are used to help identify biozones, as they make up the basic biostratigraphy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
