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:''Pope's nose redirects here. It may also refer to the licence plate light on early Volkswagen Beetles.'' Pygostyle describes a skeletal condition in which the final few caudal vertebrae are fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these. The pygostyle is the main component of the uropygium, a structure colloquially known as the parson's nose, pope's nose, or sultan's nose. This is the fleshy protuberance visible at the posterior end of a bird (most commonly a chicken or turkey) that has been dressed for cooking. It has a swollen appearance because it also contains the uropygial gland that produces preen oil. ==Evolution== Pygostyles probably began to evolve very early in the Cretaceous period, perhaps 140-130 million years ago. The earliest known species to have evolved a pygostyle were members of the Confuciusornithidae. The structure provided an evolutionary advantage, as a completely mobile tail as found in species such as ''Archaeopteryx'' is detrimental to its use for flight control. Modern birds still develop longer caudal vertebrae in their embryonic state, which later fuse to form a pygostyle. There are two main types of pygostyle: one, found in Confuciusornithidae, Enantiornithes, and some other Mesozoic birds, as well as in some oviraptorosaurs like ''Nomingia'', is long and rod- or dagger blade-like. None of the known fossils with such pygostyles show traces of well-developed rectrices. The tail feathers in these animals consisted of downy fuzz and sometimes 2-4 central "streamers" such as those found in some specimens of ''Confuciusornis'' or in ''Paraprotopteryx''.〔Clarke ''et al.'' (2006)〕 By contrast, the function of the pygostyle in the terrestrial ''Nomingia'' is not known. It is notable however that its older relative ''Caudipteryx'' had no pygostyle but a "fan" of symmetrical feathers which were probably used in social display. Perhaps such ornaments were widespread in Caenagnathoidea and their relatives, and ultimately the oviraptorosaurian pygostyle evolved to help support them. The related ''Similicaudipteryx'', described in 2008, also had a rod-like pygostyle, associated with a fan of tail feathers. The other pygostyle type is plowshare-shaped. It is found in Ornithurae (living birds and their closest relatives), and in almost all flying species is associated with an array of well-developed rectrices used in maneuvering. The central pair of these attach directly to the pygostyle, just as in ''Confuciusornis''. The other rectrices of Ornithurae are held in place and moved by structures called ''bulbi rectricium'' (rectricial bulbs), a complex feature of fat and muscles located on either side of the pygostyle. The oldest known species with such a pygostyle is ''Hongshanornis longicresta''. As evidenced by the oviraptorosaurian cases, the pygostyle evolved at least twice, and rod-shaped pygostyles seem to have evolved several times, in association with shortening of the tail but not necessarily with a retractable fan of tail feathers. In other words, the pygostyles of oviraptorosaurs and ''Confuciusornis'' were likely weight-saving measures, and the specialized "true" pygostyles of ornithurans were adapted from these later to improve flight performance.〔 The bird clade Pygostylia was named in 1996, by Luis Chiappe, for the presence of this feature and roughly corresponds to its appearance in the bird family tree, though the feature itself is not included in its definition. In 2001, Jacques Gauthier and Kevin de Queiroz (2001) re-defined Pygostylia to refer specifically to the apomorphy of a short tail bearing an avian pygostyle. 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「:'''''Pope's nose''' redirects here. It may also refer to the licence plate light on early Volkswagen Beetles.'''''Pygostyle''' describes a skeletal condition in which the final few caudal vertebrae are fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these. The pygostyle is the main component of the '''uropygium''', a structure colloquially known as the '''parson's nose''', '''pope's nose''', or '''sultan's nose'''. This is the fleshy protuberance visible at the posterior end of a bird (most commonly a chicken or turkey) that has been dressed for cooking. It has a swollen appearance because it also contains the uropygial gland that produces preen oil.==Evolution==Pygostyles probably began to evolve very early in the Cretaceous period, perhaps 140-130 million years ago. The earliest known species to have evolved a pygostyle were members of the Confuciusornithidae. The structure provided an evolutionary advantage, as a completely mobile tail as found in species such as ''Archaeopteryx'' is detrimental to its use for flight control. Modern birds still develop longer caudal vertebrae in their embryonic state, which later fuse to form a pygostyle.There are two main types of pygostyle: one, found in Confuciusornithidae, Enantiornithes, and some other Mesozoic birds, as well as in some oviraptorosaurs like ''Nomingia'', is long and rod- or dagger blade-like. None of the known fossils with such pygostyles show traces of well-developed rectrices. The tail feathers in these animals consisted of downy fuzz and sometimes 2-4 central "streamers" such as those found in some specimens of ''Confuciusornis'' or in ''Paraprotopteryx''.Clarke ''et al.'' (2006)By contrast, the function of the pygostyle in the terrestrial ''Nomingia'' is not known. It is notable however that its older relative ''Caudipteryx'' had no pygostyle but a "fan" of symmetrical feathers which were probably used in social display. Perhaps such ornaments were widespread in Caenagnathoidea and their relatives, and ultimately the oviraptorosaurian pygostyle evolved to help support them. The related ''Similicaudipteryx'', described in 2008, also had a rod-like pygostyle, associated with a fan of tail feathers.The other pygostyle type is plowshare-shaped. It is found in Ornithurae (living birds and their closest relatives), and in almost all flying species is associated with an array of well-developed rectrices used in maneuvering. The central pair of these attach directly to the pygostyle, just as in ''Confuciusornis''. The other rectrices of Ornithurae are held in place and moved by structures called ''bulbi rectricium'' (rectricial bulbs), a complex feature of fat and muscles located on either side of the pygostyle. The oldest known species with such a pygostyle is ''Hongshanornis longicresta''.As evidenced by the oviraptorosaurian cases, the pygostyle evolved at least twice, and rod-shaped pygostyles seem to have evolved several times, in association with shortening of the tail but not necessarily with a retractable fan of tail feathers. In other words, the pygostyles of oviraptorosaurs and ''Confuciusornis'' were likely weight-saving measures, and the specialized "true" pygostyles of ornithurans were adapted from these later to improve flight performance.The bird clade Pygostylia was named in 1996, by Luis Chiappe, for the presence of this feature and roughly corresponds to its appearance in the bird family tree, though the feature itself is not included in its definition. In 2001, Jacques Gauthier and Kevin de Queiroz (2001) re-defined Pygostylia to refer specifically to the apomorphy of a short tail bearing an avian pygostyle.」の詳細全文を読む :''Pope's nose redirects here. It may also refer to the licence plate light on early Volkswagen Beetles.'' Pygostyle describes a skeletal condition in which the final few caudal vertebrae are fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these. The pygostyle is the main component of the uropygium, a structure colloquially known as the parson's nose, pope's nose, or sultan's nose. This is the fleshy protuberance visible at the posterior end of a bird (most commonly a chicken or turkey) that has been dressed for cooking. It has a swollen appearance because it also contains the uropygial gland that produces preen oil. ==Evolution== Pygostyles probably began to evolve very early in the Cretaceous period, perhaps 140-130 million years ago. The earliest known species to have evolved a pygostyle were members of the Confuciusornithidae. The structure provided an evolutionary advantage, as a completely mobile tail as found in species such as ''Archaeopteryx'' is detrimental to its use for flight control. Modern birds still develop longer caudal vertebrae in their embryonic state, which later fuse to form a pygostyle. There are two main types of pygostyle: one, found in Confuciusornithidae, Enantiornithes, and some other Mesozoic birds, as well as in some oviraptorosaurs like ''Nomingia'', is long and rod- or dagger blade-like. None of the known fossils with such pygostyles show traces of well-developed rectrices. The tail feathers in these animals consisted of downy fuzz and sometimes 2-4 central "streamers" such as those found in some specimens of ''Confuciusornis'' or in ''Paraprotopteryx''.〔Clarke ''et al.'' (2006)〕 By contrast, the function of the pygostyle in the terrestrial ''Nomingia'' is not known. It is notable however that its older relative ''Caudipteryx'' had no pygostyle but a "fan" of symmetrical feathers which were probably used in social display. Perhaps such ornaments were widespread in Caenagnathoidea and their relatives, and ultimately the oviraptorosaurian pygostyle evolved to help support them. The related ''Similicaudipteryx'', described in 2008, also had a rod-like pygostyle, associated with a fan of tail feathers. The other pygostyle type is plowshare-shaped. It is found in Ornithurae (living birds and their closest relatives), and in almost all flying species is associated with an array of well-developed rectrices used in maneuvering. The central pair of these attach directly to the pygostyle, just as in ''Confuciusornis''. The other rectrices of Ornithurae are held in place and moved by structures called ''bulbi rectricium'' (rectricial bulbs), a complex feature of fat and muscles located on either side of the pygostyle. The oldest known species with such a pygostyle is ''Hongshanornis longicresta''. As evidenced by the oviraptorosaurian cases, the pygostyle evolved at least twice, and rod-shaped pygostyles seem to have evolved several times, in association with shortening of the tail but not necessarily with a retractable fan of tail feathers. In other words, the pygostyles of oviraptorosaurs and ''Confuciusornis'' were likely weight-saving measures, and the specialized "true" pygostyles of ornithurans were adapted from these later to improve flight performance.〔 The bird clade Pygostylia was named in 1996, by Luis Chiappe, for the presence of this feature and roughly corresponds to its appearance in the bird family tree, though the feature itself is not included in its definition. In 2001, Jacques Gauthier and Kevin de Queiroz (2001) re-defined Pygostylia to refer specifically to the apomorphy of a short tail bearing an avian pygostyle. 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「:''Pope's nose redirects here. It may also refer to the licence plate light on early Volkswagen Beetles.''Pygostyle describes a skeletal condition in which the final few caudal vertebrae are fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these. The pygostyle is the main component of the uropygium, a structure colloquially known as the parson's nose, pope's nose, or sultan's nose'''. This is the fleshy protuberance visible at the posterior end of a bird (most commonly a chicken or turkey) that has been dressed for cooking. It has a swollen appearance because it also contains the uropygial gland that produces preen oil.==Evolution==Pygostyles probably began to evolve very early in the Cretaceous period, perhaps 140-130 million years ago. The earliest known species to have evolved a pygostyle were members of the Confuciusornithidae. The structure provided an evolutionary advantage, as a completely mobile tail as found in species such as ''Archaeopteryx'' is detrimental to its use for flight control. Modern birds still develop longer caudal vertebrae in their embryonic state, which later fuse to form a pygostyle.There are two main types of pygostyle: one, found in Confuciusornithidae, Enantiornithes, and some other Mesozoic birds, as well as in some oviraptorosaurs like ''Nomingia'', is long and rod- or dagger blade-like. None of the known fossils with such pygostyles show traces of well-developed rectrices. The tail feathers in these animals consisted of downy fuzz and sometimes 2-4 central "streamers" such as those found in some specimens of ''Confuciusornis'' or in ''Paraprotopteryx''.Clarke ''et al.'' (2006)By contrast, the function of the pygostyle in the terrestrial ''Nomingia'' is not known. It is notable however that its older relative ''Caudipteryx'' had no pygostyle but a "fan" of symmetrical feathers which were probably used in social display. Perhaps such ornaments were widespread in Caenagnathoidea and their relatives, and ultimately the oviraptorosaurian pygostyle evolved to help support them. The related ''Similicaudipteryx'', described in 2008, also had a rod-like pygostyle, associated with a fan of tail feathers.The other pygostyle type is plowshare-shaped. It is found in Ornithurae (living birds and their closest relatives), and in almost all flying species is associated with an array of well-developed rectrices used in maneuvering. The central pair of these attach directly to the pygostyle, just as in ''Confuciusornis''. The other rectrices of Ornithurae are held in place and moved by structures called ''bulbi rectricium'' (rectricial bulbs), a complex feature of fat and muscles located on either side of the pygostyle. The oldest known species with such a pygostyle is ''Hongshanornis longicresta''.As evidenced by the oviraptorosaurian cases, the pygostyle evolved at least twice, and rod-shaped pygostyles seem to have evolved several times, in association with shortening of the tail but not necessarily with a retractable fan of tail feathers. In other words, the pygostyles of oviraptorosaurs and ''Confuciusornis'' were likely weight-saving measures, and the specialized "true" pygostyles of ornithurans were adapted from these later to improve flight performance.The bird clade Pygostylia was named in 1996, by Luis Chiappe, for the presence of this feature and roughly corresponds to its appearance in the bird family tree, though the feature itself is not included in its definition. In 2001, Jacques Gauthier and Kevin de Queiroz (2001) re-defined Pygostylia to refer specifically to the apomorphy of a short tail bearing an avian pygostyle.」の詳細全文を読む sultan's nose'''. This is the fleshy protuberance visible at the posterior end of a bird (most commonly a chicken or turkey) that has been dressed for cooking. It has a swollen appearance because it also contains the uropygial gland that produces preen oil.==Evolution==Pygostyles probably began to evolve very early in the Cretaceous period, perhaps 140-130 million years ago. The earliest known species to have evolved a pygostyle were members of the Confuciusornithidae. The structure provided an evolutionary advantage, as a completely mobile tail as found in species such as ''Archaeopteryx'' is detrimental to its use for flight control. Modern birds still develop longer caudal vertebrae in their embryonic state, which later fuse to form a pygostyle.There are two main types of pygostyle: one, found in Confuciusornithidae, Enantiornithes, and some other Mesozoic birds, as well as in some oviraptorosaurs like ''Nomingia'', is long and rod- or dagger blade-like. None of the known fossils with such pygostyles show traces of well-developed rectrices. The tail feathers in these animals consisted of downy fuzz and sometimes 2-4 central "streamers" such as those found in some specimens of ''Confuciusornis'' or in ''Paraprotopteryx''.Clarke ''et al.'' (2006)By contrast, the function of the pygostyle in the terrestrial ''Nomingia'' is not known. It is notable however that its older relative ''Caudipteryx'' had no pygostyle but a "fan" of symmetrical feathers which were probably used in social display. Perhaps such ornaments were widespread in Caenagnathoidea and their relatives, and ultimately the oviraptorosaurian pygostyle evolved to help support them. The related ''Similicaudipteryx'', described in 2008, also had a rod-like pygostyle, associated with a fan of tail feathers.The other pygostyle type is plowshare-shaped. It is found in Ornithurae (living birds and their closest relatives), and in almost all flying species is associated with an array of well-developed rectrices used in maneuvering. The central pair of these attach directly to the pygostyle, just as in ''Confuciusornis''. The other rectrices of Ornithurae are held in place and moved by structures called ''bulbi rectricium'' (rectricial bulbs), a complex feature of fat and muscles located on either side of the pygostyle. The oldest known species with such a pygostyle is ''Hongshanornis longicresta''.As evidenced by the oviraptorosaurian cases, the pygostyle evolved at least twice, and rod-shaped pygostyles seem to have evolved several times, in association with shortening of the tail but not necessarily with a retractable fan of tail feathers. In other words, the pygostyles of oviraptorosaurs and ''Confuciusornis'' were likely weight-saving measures, and the specialized "true" pygostyles of ornithurans were adapted from these later to improve flight performance.The bird clade Pygostylia was named in 1996, by Luis Chiappe, for the presence of this feature and roughly corresponds to its appearance in the bird family tree, though the feature itself is not included in its definition. In 2001, Jacques Gauthier and Kevin de Queiroz (2001) re-defined Pygostylia to refer specifically to the apomorphy of a short tail bearing an avian pygostyle.」の詳細全文を読む スポンサード リンク
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