翻訳と辞書 Words near each other ・ Coelorhyncidia elathealis ・ Coelorhyncidia flammealis ・ Coelorhyncidia nitidalis ・ Coelorhyncidia ovulalis ・ Coelorhyncidia purpurea ・ Coelorhyncidia trifidalis ・ Coelorinchus ・ Coelorinchus asteroides ・ Coelorinchus kishinouyei ・ Coelorinchus longissimus ・ Coelorinchus sheni ・ Coelorrhina ・ Coelorrhina hornimani ・ Coelosaurus antiquus ・ Coeloscleritophoran ・ Coelosimilia ・ Coelospermum ・ Coelospermum reticulatum ・ Coelosphaeriaceae ・ Coelostathma ・ Coelostathma binotata ・ Coelostathma caerulea ・ Coelostathma cocoana ・ Coelostathma contigua ・ Coelostathma continua ・ Coelostathma discopunctana ・ Coelostathma immutabilis ・ Coelostathma insularis ・ Coelostathma parallelana ・ Coelostathma placidana Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Coelosimilia ： ウィキペディア英語版 Coelosimilia ''Coelosimilia'' is a genus of extinct scleractinian coral from the Late Cretaceous period. The specimens were found in rocks around 70 million years old dating from the Late Cretaceous of the Mesozoic Era. ''Coelosimilia'' is similar to modern-day scleractinians, except for the composition of its calcitic, non-aragonitic skeleton. It is the only known scleractinian so far to have an entirely calcitic skeleton.〔 ''Coelosimilia'' is known from several specimens collected from carbonate Maastrichtian deposits located in the modern-day country of Poland. Together, these areas would have been the continental shelves of the Late Cretaceous European continent. Polish locations known to have produced specimens of the taxon include chalk-pits and quarries in Nasiłów, Lubycza Królewska and Mielnik. The specimens collected from these locations, identified as the ZPAL H.II series (6,7,8) are in the collections of the Paleobiological Institute of the Polish Academy of Sciences.〔 The discovery and analysis of ''Coelosimilia'' has changed the previous understanding of the evolution of the Scleractinia. Modern-day scleractinian corals have skeletons composed of aragonite, a calcitic mineral. Analysis of the skeleton of ''Coelosimilia'' does not seem to support development from aragonitic compounds. Instead, the skeleton is primarily calcitic — a type rarely if not ever seen in extant scleractinia. It is the first recorded instance of a scleractinian coral producing a non-aragonitic skeleton. Production of non-aragonitic skeletons by marine organisms, or the evolution of organisms capable thereof has been explained as a response to the ratio of the elements Magnesium (Mg) and Calcium (Ca) dissolved in seawater. Magnesium is a component of aragonite, and an abundance of the element is necessary for the development of aragonitic structure-building organisms. The presence of ''Coelosimilia'' during the Late Cretaceous has been suggested as an indicator of a low ratio (less than 2) of Mg to Ca in Cretaceous seas. In contrast, modern-day ratios of the two elements would be more than twice the suggested Cretaceous value, at a ratio of around 5.2.〔 This has been used as an indicator of the shifts in the ratios of the two minerals in the oceans over the geologic time scale. ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Coelosimilia」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.