Сообщество, посвящённое ра Below are the 2 most recent journal entries recorded in the "Сообщество, посвящённое ра" journal:
November 18th, 2014
09:25 pm
[industrialterro]

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Tupuxuara

 Tupuxuara is a genus of large, crested, toothless pterodactyloid pterosaur.

 The genus was named and described by Alexander Kellner and Diógenes de Almeida Campos in 1988. The type species is Tupuxuara longicristatus. The genus name refers to a familiar spirit from the mythology of the Tupi. The specific name means "long-crested" in Latin.

 The holotype, MN 6591-V, was found in the Cretaceous Santana Formation of Brazil. It consists of a snout and some partial wing bones. Mature individuals of T. longicristatus had a back-swept crest arising from the snout. Much more fossil material has later been found, showing considerable variation in morphology. Some researchers explain this as intra-specific variability, being caused by a difference in age or sex. Others, however, assume there are different species present.

 In 1994 a second species was named by Kellner: Tupuxuara leonardii. The specific name honours Giuseppe Leonardi. The holotype is MN 6592-V, a fragmentary skull with a more rounded crest. Other such material has been referred to T. leonardii. The largest skulls have a length of 130 centimetres indicating a wingspan of 5.5 metres (18 ft).

 In 2009 a third species was named, by Mark Paul Witton: Tupuxuara deliridamus. The holotype is SMNK PAL 6410, a skull. Another skull is the paratype: KPMNH DL 84. The specific name is derived from Latin delirus, "insane" or "crazy", and adamas, "invincible" but also the word from which "diamond" is derived. The species has a distinctive diamond-shaped skull opening and low eye sockets. The name is a tribute to the song "Shine On You Crazy Diamond" by Pink Floyd, one of Witton's favourite bands.

 Tupuxuara is a member of the group Azhdarchoidea. Kellner assigned it to the Tapejaridae within Azhdarchoidea. According to some analyses however, Tupuxuara is closer to the Azhdarchidae (the group that includes the giant Texan form Quetzalcoatlus) than to Tapejara and its relatives.

 It has been suggested that Tupuxuara was a fish eater at the coasts of South America. Other hypotheses include the possibility it was a fruit eater.

 A subadult described by David Martill and Darren Naish from the University of Portsmouth in 2006 had not yet fully developed its crest, which supports the suggestion that the crest was a marker for sexual maturity.

 Comparisons between the scleral rings of Tupuxuara and modern birds and reptiles suggest that it may have been diurnal.

 Для чего доисторическим летающим рептилиям были нужны гребни на головах, выяснили британские ученые - команда палеонтологов во главе с доктором Дэрреном Нэйшем из университета Портсмута.

 Редкий экземпляр черепа, найденный в Бразилии, "рассказал" исследователям, что гребень использовался птерозаврами для привлечения внимания противоположного пола - существа щеголяли своим "головным убором", демонстрируя половую зрелость. Современные павлины с той же целью используют хвост.

 "Эта поразительная структура яркого цвета походила на гребень гигантского петуха. Мы не знаем этого наверняка, но полагаем, что гребень применялся для привлечения других птерозавров", - сообщил Нэйш.

 Свою теорию ученые основывают на исследовании черепа представителя вида, известного как тупуксуара (Tupuxuara). Как оказалось, этот череп принадлежал птерозавру-подростку.

 Вместо единого большого треугольного гребня от морды до затылка у "юнца" гребень состоял из двух частей, растущих навстречу друг другу. Палеонтологи считают, что когда эти части соединялись, птерозавр достигал половой зрелости. И это становилось заметным для потенциальных партнеров.


 Репродукции (1, 2, 3, 4, 5):


 


 


 


 


 


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 Ископаемые останки и реплики (1, 2, 3, 4):


 


 


 


 


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November 11th, 2014
04:13 pm
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Thalassodromeus

 Талассодромеус (Thalassodromeus sethi, от др.-греч. θαλασσο- +δρομεύς «морской бегун», sethi — от имени Сета, из-за формы гребня) — птеродактиль из раннего мела Бразилии (формация Сантана, возраст около 122 − 109 млн.л.н.). Описан А. Келльнером и Д. Кампосом в 2002 году. Длина черепа до 1420 мм, череп высокий, имеется огромный затылочный гребень. Гребень очень тонкий, со следами кровеносных сосудов. Возможно, он служил для терморегуляции и для брачной демонстрации. На нижней челюсти в подбородочной области имеется небольшой вырост, который мог служить своеобразным килем-рассекателем, когда птерозавр опускал нижнюю челюсть в воду во время охоты. Способ питания талассодромеуса мог быть сходен со способом питания чаек-водорезов. Ящер летел низко над водой и опущенной нижней челюстью «резал» воду, выхватывая мелкую живность. В отличие от водорезов, талассодромеус мог достигать 4,5 метров в размахе крыльев. Это самое крупное известное животное, питавшееся по типу водореза. Тем не менее, недавние опыты на натурных моделях показали, что подобный способ питания для столь крупного животного был бы невозможен — челюсть создавала бы такое сопротивление, что ящер не мог бы удержать себя в воздухе. Родственные связи талассодромеуса не вполне ясны, он может быть родственником птеродактилей-тупуксар. В свою очередь, тупуксары близки к аждархидам.

 Thalassodromeus was a large pterodactyloid pterosaur found in northeastern Brazil.

 The genus was named in 2002 by Alexander Kellner and Diogenes de Almeida Campos. The type species is Thalassodromeus sethi. The genus name is derived from Greek thalasse, "sea" and dromaios, "runner", in reference to its presumed life style as a skimmer. The specific name refers to the Egyptian god Seth because of the similarity in head form. In 2006 André Jacques Veldmeijer suggested Kellner had confused Seth with the god Amun whose crown shows a remarkable resemblance with the Thalassodromeus head crest.

 The genus is based on holotype DGM 1476-R, a damaged partial skull, found in the Santana Formation. Thalassodromeus lived in the Early Cretaceous, roughly 108 million years ago. It shared the skies with its smaller cousin Tapejara. It is particularly notable for its immense head crest, beginning at the tip of the snout and ending far behind the braincase, which accounts for seventy-five percent of the surface of its 1.42 metre (4.6 ft) long skull. The jaws were pointed and toothless. It had a wing span of roughly 4.5 metres (14.7 ft). The function of the crest is unknown, but it may have been used for sexual display, species recognition, or thermoregulation. A lower jaw fragment referred to Thalassodromeus, DGM 1476-M, indicates a larger example with a wingspan of 5.3 metres (17.4 ft).

 Another jaw fragment, SAO 251093, was unofficially suggested to be a new species, "Thalassodromeus oberli" (referring to the Urs Oberli collection), by Veldmeijer in 2006, after having referred the specimen to T. sethi in 2005. In 2014 this was made a separate genus Banguela.

 Thalassodromeus was believed by Kellner to have fed in a similar way to modern skimmers; trailing its lower jaw in the water while it flew. However, later research on its jaw and neck anatomy suggested that for this and other larger pterosaurs it would not be feasible to skim because of the drag: the energy expenditure would be too high. Rather, Thalassodromeus appears to have had specialisation for terrestrial foraging like Azhdarchidae, even converging on leg proportions, and it's powerful jaws might suggest raptorial tendencies akin to those of phorusrhacids.

 Kellner assigned Thalassodromeus to the Tapejaridae. Other analyses however, showed that it was, joined with Tupuxuara in a Thalassodrominae, more closely related to the Azhdarchidae.

 Thalassodromidae (meaning "sea runners") is a family of pterodactyloid pterosaurs from the early Cretaceous period of Brazil. It contains two genera, Thalassodromeus and Tupuxuara.

 The classification of thalassodromids is controversial. Some studies, including one by Lü and colleagues in 2008, have found that the thalassodromids are more closely related to the azhdarchids than to the tapejarids, and have placed them in their own family (which has sometimes been referred to as Tupuxuaridae, though Thalassodrominae was named first). Alternately, they have been considered a subfamily (Thalassodrominae) within the Tapejaridae.

 

 Репродукции (1, 2, 3, 4, 5, 6, 7, 8):


 


 


 


 

 

 

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