Brachiopods are a large group of shelled invertebrates that live on the seabed. Their two-valved shells are of different sizes, and their shells are made of calcium or chitin. Brachiopods spend a few days to two weeks in the larval stage living a planktonic life, and then grow fleshy stems that attach to the seafloor to live a fixed life. However, there are also some species that use secondary cement or shell spines to be fixed to the seafloor or free. Live life lying down.
Long body shell
There are still 7 superfamilies, 84 genera, and nearly 300 species of brachiopods living in modern times, and they were even more prosperous in geological history, from the Cambrian 600 million years ago to the Quaternary 10,000 years ago. There are fossil records. As of 1979, 3,377 genera and more than 32,000 species had been described by scientists. These various brachiopod fossils are of great significance in determining geological time.
Owl-headed shellfish - a pierced shellfish
Scientists divide brachiopods into four classes: unhinged, eoshinated, articulated and brachiopods. Among them, the non-hinged class includes Lingula, Latoconid, Priest and Calvary; the Eo-hinged class includes Triconid and Nisoubian; the articulated class includes Orthomorph and Pentaterium. The order Brachialis includes small-mouthed mussels, perforated mussels, holeless mussels, windowless mussels and stilts.
Modern brachiopods are found in shallow, semi-abyssal and deep-sea environments, and are best suited to life in oceans with normal salinity. Apart from lingual oysters, other brachiopods are rarely found in desalinated seas. For example, the absence of brachiopods in the Baltic Sea and other northern European seas is due to low salinity. Modern brachiopods are distributed on sandy seafloor, rocky seafloor and clayey muddy seafloor. Among them, burrowing tongue-shaped shellfish prefer sandy sea bottoms, while sessile brachiopods prefer rocky sea bottoms or sea bottoms containing gravel and broken shells. Modern brachiopods also often live in symbiotic relationships with algae, corals, worms, molluscs, and echinoderms.
Shi Yan
Fossil brachiopods are found in all kinds of sedimentary rocks, but they appear more frequently in limestone, marl, shale and siltstone, and are also better preserved. Brachiopod fossils from the Paleozoic era often appear in reef strata, coexisting with animals such as corals, stromatoporoids, bryozoans and sponges that lived in normal shallow seas. Therefore, it can be speculated that the brachiopods at that time also lived in shallow seas with normal salinity. among. After the Mesozoic Era, brachiopods began to appear in symbiosis with deep-sea organisms, and fossil data can also be seen from the fossil data, the process of brachiopods spreading from shallow seas with abundant sunlight to semi-deep seas with weak light and finally to deep seas. It is this process that makes Brachiopods are living in today's oceans, whether in shallow seas, semi-deep seas or deep seas.
animal tags：
you may also like
The Xinjiang Hami scientific expedition team led by researcher Wang Xiaolin from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences and the University of Chinese Academy of Sciences, after more than ten years of continuous field scientific...
On May 26, Zhou Zhonghe’s research team at the Institute of Vertebral Paleolithology reported in Scientific Reports a new pheasant fossil material with nearly complete skeleton preservation. The specimen was found in the Hezheng area of the Linxia Basin, an area adjacent to the Qinghai-Tibet...
When people think of bacteria, the first thing that people think of are probably those pathogenic bacteria that cause diseases and destroy lives. Therefore, it is inevitable to talk about bacteria. In fact, pathogenic bacteria are only a part of bacteria, and in the vast world of bacterial fa...
The glacial fauna has long been recognized to be closely related to the global cooling events of the Pleistocene. The animals in it also showed adaptations to cold environments, such as being huge, covered in long hair, and having body structures that can scrape snow. Mammoths and woolly rhin...
In the early 20th century, some Western scholars, based on the evolution of mammals and changes in the natural environment since the Tertiary Period, inferred that Central Asia (including northwest China and Mongolia), the vast arid and barren wilderness today, was in the distant past. It is...
Bryos and mosses in plants are two different things! They are a type of primitive aquatic group animals with tiny individuals. However, their body structure is more evolved than that of worms, with three germ layers and a true body cavity, and their bodies are not segmented. They are called "...
Vertebrates are the highest group in the animal kingdom. They form a subphylum of the phylum Chordata in the animal kingdom - the subphylum Vertebrates. Vertebrate skeleton pattern diagram There is a spine in the body of vertebrates, which is connecte...
While Dart and Bloom continued to discover Australopithecus in South Africa, the famous British paleoanthropologists Leakey and his wife (Louis Leakey and Mary Leakey) were also working hard in East Africa. On July 17, 1959, after nearly 30 years of unremitting search, they finally got their...
Email: jsset#163.com (change # to @) Please indicate your purpose of visit! Guangdong ICP No. 2022053326 XML| map| Chinese
