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Guiyu Oneiros
''Guiyu oneiros'' is one of the earliest articulated Osteichthyes, bony fish discovered. Fossils of ''Guiyu'' have been found in what is now Qujing, Yunnan, China, in late Silurian marine strata, about 425 million years old. ''Guiyu'' is part of the Xiaoxiang fauna which is rich in fossils representing a marine ecosystem. Found in the late Silurian#Ludlow, Ludlow-aged Kuanti Formation, the remains were dated using conodonts as index fossils. The Xiaoxiang fauna also includes galeaspids, placoderms and acanthodians. Discovery and naming ''Guiyu'' was described by Chinese palaeontologist Zhu Min (:zh:朱敏 (古生物学家), 朱敏) and others in 2009, based on a near-complete articulated specimen. The generic name ''Guiyu'' is a transliteration of the Mandarin 鬼魚 ''guǐyú'' "Ghosts in Chinese culture, ghost fish" and the specific name ''oneiros'' is from Greek ὄνειρος "dream". Description The holotype specimen is about in length and about in depth. The caudal f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ludlow Epoch
In the geological timescale, the Ludlow Epoch (from 427.4 ± 0.5 million years ago to 423.0 ± 2.3 million years ago) occurred during the Silurian Period, after the end of the Homerian Age. It is named for the town of Ludlow in Shropshire, England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It .... The Ludlow Epoch is subdivided into two stages: Gorstian and Ludfordian. See also * Ludlow Group References *03 Geological epochs {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Gnathostome
Gnathostomata (; from Ancient Greek: (') 'jaw' + (') 'mouth') are jawed vertebrates. Gnathostome diversity comprises roughly 60,000 species, which accounts for 99% of all extant vertebrates, including all living bony fishes (both ray-finned and lobe-finned, including their terrestrial tetrapod relatives) and cartilaginous fishes, as well as extinct prehistoric fish such as placoderms and acanthodians. Most gnathostomes have retained ancestral traits like true teeth, a stomach, and paired appendages ( pectoral and pelvic fins, limbs, wings, etc.). Other traits are elastin, horizontal semicircular canal of the inner ear, myelinated neurons, and an adaptive immune system which has discrete secondary lymphoid organs (spleen and thymus) and uses V(D)J recombination to create antigen recognition sites, rather than using genetic recombination in the variable lymphocyte receptor gene. It is now assumed that Gnathostomata evolved from ancestors that already possessed two pairs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Life Restoration Of Guiyu Oneiros
Life, also known as biota, refers to matter that has biological processes, such as Cell signaling, signaling and self-sustaining processes. It is defined descriptively by the capacity for homeostasis, Structure#Biological, organisation, metabolism, Cell growth, growth, adaptation, response to stimulus (physiology), stimuli, and reproduction. All life over time eventually reaches a state of death, and none is Immortality, immortal. Many philosophical definitions of living systems have been proposed, such as self-organizing systems. Viruses in particular make definition difficult as they replicate only in Host (biology), host cells. Life exists all over the Earth in air, water, and soil, with many ecosystems forming the biosphere. Some of these are harsh environments occupied only by extremophiles. Life has been studied since ancient times, with theories such as Empedocles's materialism asserting that it was composed of Classical element, four eternal elements, and Aristotle's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ganoine
Ganoine or ''ganoin'' is a glassy, often multi-layered mineralized tissue that covers the scales, cranial bones and fin rays in some non-teleost ray-finned fishes, such as gars and bichirs, as well as lobe-finned coelacanths. It is composed of rod-like, pseudoprismatic apatite crystallites, with less than 5% of organic matter. Existing fish groups featuring ganoin are bichirs and gars, but ganoin is also characteristic of several extinct taxa. It is a characteristic component of ganoid scales. Ganoine is an ancient feature of ray-finned fishes, being found for example on the scales of stem group actinopteryigian ''Cheirolepis''. While often considered a synapomorphic character of ray-finned fishes, ganoine or ganoine-like tissues are also found on the extinct acanthodii. It has been suggested that ganoine is homologous to tooth enamel in vertebrates or even considered a type of enamel. Ganoine indeed contains amelogenin-like proteins and has a mineral content similar to that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
