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2017 In Paleontology
Flora Cnidarians Research * Ou ''et al.'' (2017) consider early Cambrian species ''Galeaplumosus abilus'' and ''Chengjiangopenna wangii'' to be Synonym (taxonomy), junior synonyms of ''Xianguangia sinica'', interpret fossils attributed to members of these species as parts of the same organism and consider ''X. sinica'' to be likely Crown group#Stem groups, stem-cnidarian. * ''Pseudooides prima'' is interpreted as a cnidarian and a senior synonym of ''Hexaconularia sichuanensis'' by Duan ''et al.'' (2017). * Fossilized cnidarian Jellyfish#Terminology, medusae are described from the Cambrian Zabriskie Quartzite (California, United States) by Sappenfield, Tarhan & Droser (2017), representing the oldest macrofossil evidence of cnidarian medusae from the Phanerozoic reported so far. * A study on the Morphology (biology), morphology of phosphatic tubes of ''Sphenothallus'' from the Early Ordovician Fenxiang Formation (China), as well as the Silurian and Early Devonian of Podolia (U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphenothallus
''Sphenothallus'' is a problematic extinct genus lately attributed to the conulariids. It was widespread in shallow marine environments during the Paleozoic. Occurrence ''Sphenothallus'' is represented in the Cambrian period in the Kaili biota and the Mount Stephen trilobite beds, where it co-occurs with the similar organisms '' Cambrorhythium'' and '' Byronia''. It is known in younger strata in Canada and the US, surviving at least until the Mississippian. Ecology ''Sphenothallus'' lived in groups as an opportunist in environments from hardground Carbonate hardgrounds are surfaces of synsedimentarily cemented carbonate layers that have been exposed on the seafloor (Wilson and Palmer, 1992). A hardground is essentially, then, a lithified seafloor. Ancient hardgrounds are found in limeston ...s to soft mud, even if depleted in oxygen. It probably dispersed via larvae. Notes References External links * {{Taxonbar, from=Q7576667 Burgess Shale fossils Stau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosynthesis
Photosynthesis ( ) is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabolism. ''Photosynthesis'' usually refers to oxygenic photosynthesis, a process that produces oxygen. Photosynthetic organisms store the chemical energy so produced within intracellular organic compounds (compounds containing carbon) like sugars, glycogen, cellulose and starches. To use this stored chemical energy, an organism's cells metabolize the organic compounds through cellular respiration. Photosynthesis plays a critical role in producing and maintaining the oxygen content of the Earth's atmosphere, and it supplies most of the biological energy necessary for complex life on Earth. Some bacteria also perform anoxygenic photosynthesis, which uses bacteriochlorophyll to split hydrogen sulfide as a reductant instead of water, p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbiosis
Symbiosis (Ancient Greek : living with, companionship < : together; and ''bíōsis'': living) is any type of a close and long-term biological interaction, between two organisms of different species. The two organisms, termed symbionts, can for example be in Mutualism (biology), mutualistic, commensalism, commensalistic, or parasitism, parasitic relationships. In 1879, Heinrich Anton de Bary defined symbiosis as "the living together of unlike organisms". The term is sometimes more exclusively used in a restricted, mutualistic sense, where both symbionts contribute to each other's subsistence. This means that they benefit each other in some way. Symbiosis can be ''obligate'' (or ''obligative''), which means that one, or both of the organisms depend on each other for survival, or ''facultative'' (optional), when they can also subsist independently. Symbiosis is also classified by physical attachment. Symbionts forming a single body live ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scleractinia
Scleractinia, also called stony corals or hard corals, are marine animals in the phylum Cnidaria that build themselves a hard skeleton. The individual animals are known as polyps and have a cylindrical body crowned by an oral disc in which a mouth is fringed with tentacles. Although some species are solitary, most are colonial. The founding polyp settles and starts to secrete calcium carbonate to protect its soft body. Solitary corals can be as much as across but in colonial species the polyps are usually only a few millimetres in diameter. These polyps reproduce asexually by budding, but remain attached to each other, forming a multi-polyp colony of clones with a common skeleton, which may be up to several metres in diameter or height according to species. The shape and appearance of each coral colony depends not only on the species, but also on its location, depth, the amount of water movement and other factors. Many shallow-water corals contain symbiont unicellular organis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coral
Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral reef, reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton. A coral "group" is a colony of very many cloning, genetically identical polyps. Each polyp is a sac-like animal typically only a few millimeters in diameter and a few centimeters in height. A set of tentacles surround a central mouth opening. Each polyp excretes an exoskeleton near the base. Over many generations, the colony thus creates a skeleton characteristic of the species which can measure up to several meters in size. Individual colonies grow by asexual reproduction of polyps. Corals also breed sexually by spawning: polyps of the same species release gametes simultaneously overnight, often around a full moon. Fertilized eggs form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lethaia
''Lethaia'' is a quarterly peer-reviewed scientific journal of Earth science, covering research on palaeontology and stratigraphy. Now published by Scandinavian University Press, it was originally published by the International Commission on Stratigraphy. It is an official publication of the International Palaeontological Association and the International Commission on Stratigraphy. The journal had a 2012 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 2.488, ranking it 7th out of 48 journals in the category "Paleontology", though its IF has since declined. References External links * Paleontology journals Wiley-Blackwell academic journals English-language journals Academic journals established in 1968 Quarterly journals {{paleontology-journal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jerzy Dzik
Jerzy Dzik (born 25 February 1950) is a Polish paleontologist. He has described many species, genera, and families of conodonts, including the Order (biology), order Ozarkodinida (in 1976). In 2003, he described the Dinosauriformes, dinosauriform ''Silesaurus'', from the Triassic of Poland.Dzik, J. (2003). "A beaked herbivorous archosaur with dinosaur affinities from the early Late Triassic of Poland." Journal of Vertebrate Paleontology, 23(3): 556-574. Tributes The conodont genus name ''Dzikodus'' Zhang 1998 is a tribute to J. Dzik. References * Dzik, J. 1975a. Spiroboloid millipeds from the Late Cretaceous of the Gobi Desert, Mongolia. Palaeontologia Polonica 33, 17-24. * Dzik, J. 1975b. The origin and early phylogeny of the cheilostomatous Bryozoa. Acta Palaeontologica Polonica 20, 3, 395-423. * Dzik, J. 1978a. A myodocopid ostracode with preserved appendages from the Upper Jurassic of the Volga River Region (USSR). Neues Jahrbuch für Geologie und Paläontologie, Monat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ukraine
Ukraine is a country in Eastern Europe. It is the List of European countries by area, second-largest country in Europe after Russia, which Russia–Ukraine border, borders it to the east and northeast. Ukraine also borders Belarus to the north; Poland and Slovakia to the west; Hungary, Romania and Moldova to the southwest; and the Black Sea and the Sea of Azov to the south and southeast. Kyiv is the nation's capital and List of cities in Ukraine, largest city, followed by Kharkiv, Odesa, and Dnipro. Ukraine's official language is Ukrainian language, Ukrainian. Humans have inhabited Ukraine since 32,000 BC. During the Middle Ages, it was the site of early Slavs, early Slavic expansion and later became a key centre of East Slavs, East Slavic culture under the state of Kievan Rus', which emerged in the 9th century. Kievan Rus' became the largest and most powerful realm in Europe in the 10th and 11th centuries, but gradually disintegrated into rival regional powers before being d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podolia
Podolia or Podillia is a historic region in Eastern Europe located in the west-central and southwestern parts of Ukraine and northeastern Moldova (i.e. northern Transnistria). Podolia is bordered by the Dniester River and Boh River. It features an elongated plateau and fertile agricultural land covering an area of . The two main rivers serve as important trade channels. Podolia is known for its cherries, mulberries, melons, gourds, and cucumbers. The region has a rich history, dating back to the Neolithic, with various tribes and civilizations occupying it over time. It became part of the Kingdom of Galicia–Volhynia, the Golden Horde, the Kingdom of Poland, the Grand Duchy of Lithuania, the Ottoman Empire, the Habsburg monarchy of Austria, and the Russian Empire. In the 20th century, Podolia underwent various political changes, with both the Second Polish Republic and the Soviet Union controlling parts of it at different times. Podolian culture is renowned for its folk icon-p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian
The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian period at million years ago (Megaannum, Ma), to the beginning of the succeeding Carboniferous period at Ma. It is the fourth period of both the Paleozoic and the Phanerozoic. It is named after Devon, South West England, where rocks from this period were first studied. The first significant evolutionary radiation of history of life#Colonization of land, life on land occurred during the Devonian, as free-spore, sporing land plants (pteridophytes) began to spread across dry land, forming extensive coal forests which covered the continents. By the middle of the Devonian, several groups of vascular plants had evolved leaf, leaves and true roots, and by the end of the period the first seed-bearing plants (Pteridospermatophyta, pteridospermatophyt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silurian
The Silurian ( ) is a geologic period and system spanning 23.5 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the third and shortest period of the Paleozoic Era, and the third of twelve periods of the Phanerozoic Eon. As with other geologic periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by a few million years. The base of the Silurian is set at a series of major Ordovician–Silurian extinction events when up to 60% of marine genera were wiped out. One important event in this period was the initial establishment of terrestrial life in what is known as the Silurian-Devonian Terrestrial Revolution: vascular plants emerged from more primitive land plants, dikaryan fungi started expanding and diversifying along with glomeromycotan fungi, and three groups of arthropods ( myriapods, arachnids and hexapods) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
