Jurodivost (ili ludost radi Krista) (rus. юродство) naizgled je nerazumno ponašanje u religijske svrhe, odricanje od svjetovnoga načina života, dragovoljno siromaštvo, koje je zastupljeno u kršćanstvu, gdje se smatra jednim od najtežih i najsmjelijih oblika nasljedovanja vjere.

Jurodivi (osobe koje prakticiraju jurodivost) obično koriste šokiranje i nekonvecionalno ponašanje radi propitivanja prihvaćenih normi, prorokovanja ili prikrivanja vlastite pobožnosti. Dobrovoljno se odriču svih zemaljskih dobara, svojih srodnika, postojbine, svijeta u kojem žive i uobičajenoga svjetovnoga ponašanja.

Jurodivost podrazumijeva dvojni život - vanjski, koji se kosi s normama ovoga svijeta, i unutrašnji, gdje duša živi u ljubavi prema Bogu.

Jurodivi preziru svjetovne običaje i bližnjima su povod za sablazan, izlažući se poruzi okoline. Hrana, odjeća i dom, a pogotovo bogatstvo, moć i vlast ne predstavljaju im ni vrijednost, ni neophodnu potrebu. Poste od hrane, puno se mole, odijevaju se vrlo skromno, nemaju svoju materijalnu imovinu ni nekretnine u svom vlasništvu. Smatra se da doslovno ispunjavaju Isusove riječi: "Zato vam kažem: Ne budite zabrinuti za život svoj: što ćete jesti, što ćete piti; ni za tijelo svoje: u što ćete se obući. Zar život nije vrijedniji od jela i tijelo od odijela?" "Pogledajte ptice nebeske! Ne siju, ne žanju niti sabiru u žitnice, pa ipak ih hrani vaš nebeski Otac." (Mt 6, 25-26).

Oni često ukazuju na proturiječnosti i licemjerje između istinskoga kršćanstva i društvene nemoralnosti. U Rusiji, jurodivi preuzimaju i društveno značajan podvig izobličavanja silnika ovoga svijeta, iskorijenjivanja zla i zaštite potlačenih, tako da asketskoj strani dodaju i izraženu socijalnu dimenziju.

Primjeri jurodivosti
Svjedočanstva koja bi se mogla smatrati uzorima jurodivosti nudi još Stari zavjet. Postupci pojedinih starozavjetnih proroka čine se teško razumljivim i čudnima: tako je Izaija, predskazujući sužanjstvo Misiraca i Etiopljana, tri godine hodao gol i bos (Iz 20, 2-3); Jeremija je načinio sebi jaram oko vrata da bi ga poslao gospodarima susjednih zemalja za svjedočanstvo volje Božje (Jr 27 i 28); Ezekiel, predstavljajući opsadu Jeruzalema i prorokujući protiv onih što prestupiše zakon Božji, 390 dana ležao je na lijevoj i 40 dana na desnoj strani svoga tijela, jedući pljesnjiv kruh (Ez 4, 1-12); prorok Hosea oženio se prostitutkom na Božji zahtjev kao simbol stanja u društvu, jer se Izrael udaljio od Gospodina (Hos. 1, 1-3).

Sv. Ivan Krstitelj svojom je pojavom, vrlo asketskim životom u pustinji, propovijedanjem pokajanja i razobličavanjem silnika ovoga svijeta također pokazivao crte jurodivosti. Apostol Pavao u Prvoj poslanici Korinćanima izlaže misli koje će utemeljiti najbitnije odlike jurodivosti: "a mi propovijedamo Krista raspetoga: Židovima sablazan, poganima ludost, pozvanima pak - i Židovima i Grcima - Krista, Božju snagu i Božju mudrost. Jer ludo Božje mudrije je od ljudi i slabo Božje jače je od ljudi. Ta gledajte, braćo, sebe, pozvane: nema mnogo mudrih po tijelu, nema mnogo snažnih, nema mnogo plemenitih. Nego lude svijeta izabra Bog da posrami mudre, i slabe svijeta izabra Bog da posrami jake; i neplemenite svijeta i prezrene izabra Bog, i ono što nije, da uništi ono što jest, da se nijedan smrtnik ne bi hvalio pred Bogom". (1 Kor 1, 23-29).

Sv. Šimun Stilit iz 5. stoljeća, živio je 37 godina na vrhu stupa (grč. stylos), po čemu je dobio i naziv Stilit. Nakon života u špilji na neko vrijeme, premjestio se na vrh stupa. Želio je imati mir od tolikog broja ljudi i postići veću osamljenost, a opet nije ih htio posve odbiti, pa je napravio stup visok 20 metara i na njegovu vrhu mali ograđeni prostor u kojem je stanovao i na kojem je proveo ostatak života. Privukao je mnogo ljudi koji su došli iz daljine čuti ga kako propovijeda dva puta dnevno. Mnogi su mu se obraćali za savjet, pomoć, molitveni zagovor, čak i rimski carevi. Nakon njega, bilo je još redovnika, koji su živjeli na vrhu stupa i dobili su ime Stilit, prema grčkoj rijeci stylos za stup.

Najpoznatiji primjer na Zapadu je sv. Franjo Asiški, čiji je franjevački red poznat po vjernom nasljedovanju Kristova učenja. Sveti Franjo povukao se u prirodu i samoću, a družio se sa siromasima, te odjeven u vreću poslužuje gubavce. Nakon viđenja u crkvici svetog Damjana u Asizu, u kojem mu Krist s križa kaže: »Franjo, idi i obnovi moju Crkvu«, počinje popravljati tu ruševnu crkvu. Sugrađani su ga ispočetka smatrali čudakom, pa i luđakom, ali njegovo propovijedanje o apsolutnom evanđeoskom siromaštvu u doba oštro naglašenih klasno-ekonomskih razlika u feudalnom društvu nalazi pristalice među narodom i siromašnim slojevima građanstva. Broj Franjine pokorničke braće s vremenom je sve više rastao te se pokret svetog siromaštva širi velikom brzinom i postaje prijetnja za privilegirani položaj klera. Kako bi suzbio tu opasnost papa Inocent III. poziva Franju pred sebe i nakon što dobiva garancije da će pokret poštovati sva svjetovna prava Crkve i besprizivno se podlagati papinu autoritetu odobrava njegovo djelovanje.

Sveti Benedikt Josip Labre u 18. stoljeću, iskusio je želju za koju je smatrao da mu je Bog dao i inspiriran primjerom sv. Aleksija Rimskoga i sv. Roka napustio je svoju zemlju, roditelje i sve što je primamljivo u svijetu i odlučio se na novu vrstu života, posjećivao je hodočasnička mjesta. Tijekom tih putovanja uvijek bi hodao pješice, spavao na otvorenom ili u kutu prostorije, s blatnjavom odjećom. Rijetko je razgovarao, često molio i mirno prihvaćao sve tegobe na putovanjima.

U Rusiji
Najveći procvat jurodivost doživljava u Rusiji, gdje se razvija počevši od 11. pa sve do 17. stoljeća. Ruska pravoslavna crkva kanonizirala je ukupno 37 jurodiva, najviše iz 15. i 16. stoljeća (npr. Vasilije Blaženi). U to doba u Rusiji je, sudeći po pisanim spomenicima, bilo prilično jurodivih; smatra se da su u Moskvi oni činili čak i poseban stalež. Krajem 16. i tijekom čitavog 17. stoljeća opada poštovanje jurodivih u narodu, a smanjuje se i broj onih koji bivaju dostojni crkvene kanonizacije. Bez duhovne podrške i fizički progonjeno od policije, jurodivost biva potisnuto. Crkva protiv jurodivih izdaje više ukaza, obznanjujući da njihova djela nemaju na sebi blagoslov. Pa ipak, pojedini slučajevi kanoniziranja jurodivih sreću se i tijekom 18., 19. i 20. stoljeća poput kanonizacije Ksenije Petrogradske.

Izvori

Kršćanstvo
Društvo

Jurodivost


Karanlık Bir Dünyada Bilimin Mum Işığı, orijinal adı The Demon-Haunted World/Science as a Candle in the Dark. Carl Sagan'ın bilimsel yöntemi övdüğü ve bilim dışı yöntemlerin yanlışlıklarını anlattığı kitabıdır.

1995 yılında yazılan kitabın Türkiye'deki ilk baskısı 1998 yılında yapılmıştır. Tübitak Popüler Bilim Kitapları'nda 85 numaralı kitap olarak yayımlanmıştır. Türkçeye Miyase Göktepeli tarafından çevrilmiştir. Tüm yayın hakları Tübitak'a aittir.

Kitabın bölümleri

 En Değerli Şey
 Bilim ve Umut
 Ay'daki Adam, Mars'taki Yüz
 Uzaylılar
 Aldatmaca ve Gizlilik
 Sanrılar
 İblisli Dünya
 Gerçek ve Sahte Düşlerin Ayrımı
 Terapi
 Garajımdaki Ejder
 Yas Kenti
 Yutturmaca Saptama Sanatı
 Gerçeklik Saplantısı
 Karşıtbilim
 Newton'un Uykusu
 Bilim Adamları Günahı Tattığında
 Kuşkuculuk ve Merakın Evliliği
 Rüzgâr Toz Kaldırır
 Aptalca Soru Yoktur
 Yanan Ev
 Özgürlüğe Giden Yol
 Anlamkeşler
 Maxwell ve İnekler
 Bilim ve Cadılık
 Gerçek Yurtseverler Soru Sorar

Dış bağlantılar

 Carl Sagan resmi web sitesi

Bilim kitapları
Carl Sagan eserleri
1995 kitapları
İngilizce kitaplar
Amerikan kitapları
Amerikan araştırma kitapları
Din eleştirisi kitapları
Random House kitapları

Karanlık Bir Dünyada Bilimin Mum Işığı


Crkva Krista radnika i Gospe Lurdske (španjolski: Iglesia de Cristo Obrero y Nuestra Señora de Lourdes), također poznata kao i Crkva Atlántida, rimokatolička je župna crkva u Estación Atlántidi u Urugvaju, 45 km od Montevidea. Crkva je posvećena Kristu Radniku i Gospi Lurdskoj i predstavlja poznato arhitektonsko djelo koje je projektirao urugvajski arhitekt Eladio Dieste 1952.-1958. godine.

Godine 2021. crkva je uvrštena ma UNESCO-ov popis mjesta svjetske baštine u Amerikama pod nazivom "Rad inženjera Eladija Diestea: Crkva Atlántida" jer predstavlja "značajan primjer izvanrednih formalnih i prostornih postignuća moderne arhitekture u Latinskoj Americi tijekom drugog dijela 20. stoljeća, utjelovljujući potragu za društvenom jednakošću uz štedljivo korištenje resursa, ispunjavajući graditeljska načela za postizanje visokog estetskog učinka".

Opis

Arhitektonski upečatljivu jednobrodnu građevinu čini jednostavan pravokutnik (16 x 30 m), s bočnim stijenkama koje se uzdižu 7 m u zavojitim krivuljama do maksimalne amplitude lukova. Konstrukcijski, zid se sastoji od dvostruke ploče od opeke sa praznom komorom u sredini, koja je ispunjenom žbukom i čeličnom armaturom promjera 3 mm. Zmijoliki zidovi podupiru valoviti krov, sastavljen od niza armiranih "gausovih svodova" od opeke koje je razvio Eladio Dieste. Riječ je o tankoljusnoj strukturi krova debljine jedne opeke koja svoju čvrstoću dobiva od dvostruke zakrivljenosti lančanog luka koji odolijeva izvijanju.

Iznad ulaza je kor smješten na polukatu. Taj je prostor izvana zatvoren zidom koji čine ploče od tokarene opeke u odnosu na ravninu zida. Ovim suptilnim pokretom ostvaren je dojam zabata koji izgleda kao da dominira glavnim pročeljem i također stvara nijanse prirodnog svjetla, stvarajući kontraste i gradijente iznutra.

Cilindrični zvonik sa stijenama za penjanje iznutra, uzdiže se 15 m od tla, 8 m desno od pročelja glavne crkve. To je kružni toranj promjera oko 3 metra i zidova debljine samo 30 cm.
Podzemna krstionica nalazi s lijeve strane predvorja i dostupna je s trokutastog prizmatičnog ulaza i osvijetljena putem središnjih okulusa.

Materijal koji je korišten je jednostavna izložena opeka, ali predstavlja novitet uporabe opeke u ojačanoj konstrukciji, bez stupova i greda. Žbuka i čelik korišteni su samo kao elementi koji ojačavaju zid od opeke, omogućujući mu strukturnu aktivnost. Matematičkim izračunom ovaj je projekt koristio opeku kao nosivi element zgrade, pokušavajući se odmaknuti od tada aktualnih međunarodnih sustava gradnje. Prema Diesteu, "zdrava arhitektura ne može se proizvesti bez racionalnog i ekonomičnog korištenja materijala u gradnji". Ova lagana konstrukcija, izrazito jeftina, arhitektonski je objekt velike graditeljske vještine, koja ekspresivne mogućnosti opeke dovodi do njihovog vrhunca.

Unutra se nalazi izrezbareno drveno Raspelo koji je izradio kipar Eduardo Díaz Yepes i oltar sastavljen od bloka grubog zelenog granita.

Izvori

Vanjske poveznice

Katoličke crkve u Urugvaju
Svjetska baština u Južnoj Americi
Biskupija Canelones

Crkva Atlántida


Consuelo da Luz Lins (* im 20. Jahrhundert) ist eine brasilianische Filmwissenschaftlerin, die sich mit Dokumentarfilmen befasst.

Sie studierte von 1978 bis 1982 an der Päpstlichen Katholischen Universität von Rio de Janeiro (PUC-Rio) Kommunikationswissenschaft. Seit 1995 ist Lins Professorin an der Kommunikationswissenschaftlichen Fakultät der Bundesuniversität von Rio de Janeiro. In der Nähe befindet sich das Armenviertel Babilônia, in das sie Eduardo Coutinho für dessen gleichnamigen Film (Babilônia 2000) einführen konnte.

Sie realisierte den Dokumentarfilm Babas über Kinderfrauen in Rio de Janeiro.

Schriften
 Filmar o real: sobre o documentário brasileiro contemporâneo. 2010. ISBN 978-85-378-0082-9
 Rua de Mão Dupla: documentário e arte contemporânea. In: K. Maciel (Hrsg.): Transcinemas. Rio de Janeiro 2009.
 O cinema de Chris Marker: entre a carta e o ensaio fílmico. In: Chris Marker: Bricoleur Multimídia.
 O Documentário de Eduardo Coutinho: televisão, cinema e vídeo. 2010.
 Rindo de quê? O Humor no documentário de Eduardo Coutinho.
 Imagem e Tempo na série Futebol, de João Salles, in Estudos de Cinema Socine.
 O que é isso, companheiro? a ficção resiste sem a história? In: César Benjamin, Elio Gaspari, Daniel Aarão Reis: Versões e ficções: o seqüestro da história. Ed. Fund. Perseu Abramo, São Paulo 1997.

Weblinks
 "Consuelo da Luz Lins", Lebenslauf (CNPq)

 Ariane Mondo/Lars dos Santos Drawert: Interview mit Consuelo Lins am Dok Leipzig, Oktober 2010.
 Profil von Consuelo Lins auf der Website der Escola de Comunicação der Bundesuniversität von Rio de Janeiro.
 Profil von Consuelo Lins beim Verlag Jorge Zahar
 academia.edu Curriculum Vitae Consuelo Lins, abgerufen am 8. November 2019

Nachweise

Filmwissenschaftler
Hochschullehrer (Universidade Federal do Rio de Janeiro)
Brasilianer
Geboren im 20. Jahrhundert
Frau

Consuelo Lins


The Hoosier National Forest is a property managed by the United States Forest Service in the hills of southern
Indiana. Composed of four separate sections, it has a total area of . Hoosier National Forest's headquarters are located in Bedford, with a regional office in Tell City. Prominent places within the Forest include the Lick Creek Settlement, Potts Creek Rockshelter Archeological Site, and Jacob Rickenbaugh House.

History
Hoosier National Forest was first touched by humanity 12,000 years ago, when Native Americans in the United States hunted in the forest. Europeans reached the forest in the late 17th century, and began building villages in the forest. Actual lumbering began in the 19th century, with the cutting of more difficult terrain occurring after 1865. By 1910 most of the area had been cut. In the early 1930s the governor of Indiana pushed for the federal government to do something with the eroding lands that saw its residents leaving, with the act being accomplished on February 6, 1935.

Within Hoosier National Forest, two miles (3 km) south of Chambersburg, lies the former Lick Creek Settlement Site, a settlement of free blacks led by the Quaker Jonathan Lindley from around 1819 to around 1865.
Pioneer Mothers Memorial Forest near Paoli contains an excellent example of virgin forest.  Hemlock Cliffs Recreation Area in Crawford County contains one of the most scenic hiking trails in Indiana.

Most of Thomas Hines' Hines' Raid was within the present-day Hoosier National Forest.

Hickory Ridge Lookout Tower is the sole remaining fire tower out of eight that once stood within Hoosier National Forest. When built, there was a two-room house for the ranger and his dependents to live within, but it has since been destroyed. Visitors may still climb the tower, but are recommended to be cautious when climbing.

Maumee Scout Reservation and Lake Tarzian are also located within the Hoosier National Forest. Lake Tarzian is named after Sarkes Tarzian who led the capital campaign to build the camp.

Science

Much of Hoosier National Forest is over karst, responsible for the many caves in southern Indiana.

Included in Hoosier National Forest is the Charles C. Deam Wilderness Area, the only recognized wilderness area left in Indiana. This means that no motorized vehicles are allowed in the area, and instead mules and horses must be used to maintain hiking trails.

In the Clover Lick Barrens, the southern portion of Hoosier National Forest near the Ohio River, the vegetation is more typical of that found on prairies in the Great Plains. This was discovered by a botanist and biologist from the Indiana Department of Natural Resources, who later found that in the first recorded survey of the area in 2005, the land was described not as forest, but as "a mile of poor barrens and grassy hills". It is believed that the inability of tall oaks to grow in the area allows for this prairie vegetation to persist in such an unlikely location. In 2006 a conscious effort was made to keep the barren look to the area; previous federal efforts on renovating Hoosier National Forest meant adding nonnative species to low-growth areas. It was around Clover Lick in 1972 that Indiana decided to reintroduce wild turkeys back to Indiana, dedicating  for the purpose.

Also found in Hoosier National Forest is Sundance Lake, a  lake.

Hoosier National Forest lies in parts of nine counties in southern Indiana.

Recreation
The trail system has almost , and allows horseback riding and mountain bikes, along with hiking. Hikers are to yield to horses, and mountain bikers are to yield to both of them. Within the Hemlock Cliffs Valley, located within the central portion of the National Forest, there is the 1.2 mile Hemlock Cliffs trail. The trail is noted as access to sandstone cliffs and seasonal waterfalls as well as Hemlock trees and rare wintergreen plants.

Hoosier National Forest Trail System

All trail locations are within the state of Indiana.

See also
Charles C. Deam Wilderness Area

References

External links

National Forests of Indiana
Protected areas of Brown County, Indiana
Protected areas of Lawrence County, Indiana
Protected areas of Perry County, Indiana
Protected areas of Crawford County, Indiana
Protected areas of Dubois County, Indiana
Protected areas of Monroe County, Indiana
Protected areas of Orange County, Indiana
Protected areas of Jackson County, Indiana
Protected areas of Martin County, Indiana
1961 establishments in Indiana
Protected areas established in 1961

Hoosier National Forest


Rhamphorhynchus (, from Ancient Greek rhamphos meaning "beak" and rhynchus meaning "snout") is a genus of long-tailed pterosaurs in the Jurassic period. Less specialized than contemporary, short-tailed pterodactyloid pterosaurs such as Pterodactylus, it had a long tail, stiffened with ligaments, which ended in a characteristic soft-tissue tail vane. The mouth of Rhamphorhynchus housed needle-like teeth, which were angled forward, with a curved, sharp, beak-like tip lacking teeth, indicating a diet mainly of fish; indeed, fish and cephalopod remains are frequently found in Rhamphorhynchus abdominal contents, as well as in their coprolites.

Although fragmentary fossil remains possibly belonging to Rhamphorhynchus have been found in England, Tanzania, and Spain, the best preserved specimens come from the Solnhofen limestone of Bavaria, Germany. Many of these fossils preserve not only the bones but impressions of soft tissues, such as wing membranes. Scattered teeth believed to belong to Rhamphorhynchus have been found in Portugal as well.

History and classification

The classification and taxonomy of Rhamphorhynchus, like many pterosaur species known since the Victorian era, is complex, with a long history of reclassification under a variety of names, often for the same specimens.

The first named specimen of Rhamphorhynchus was brought to the attention of Samuel Thomas von Sömmerring by the collector Georg Graf zu Münster in 1825. Von Sömmerring concluded that it belonged to an ancient bird. When further preparation uncovered teeth, Graf zu Münster sent a cast to Professor Georg August Goldfuss, who recognised it as a pterosaur. Like most pterosaurs described in the mid 19th century, Rhamphorhynchus was originally considered to be a species of Pterodactylus. However, at the time, many scientists incorrectly considered Ornithocephalus to be the valid name for Pterodactylus. This specimen of Rhamphorhynchus was therefore originally named Ornithocephalus Münsteri. This was first mentioned in 1830 by Graf zu Münster himself. However, the description making the name valid was given by Goldfuss in an 1831 follow-up to Münster's short paper. Note that the ICZN later ruled that non-standard Latin characters, such as ü, would not be allowed in scientific names, and the spelling münsteri was emended to muensteri by Richard Lydekker in 1888.

In 1839, Münster described another specimen that he considered to belong to Ornithocephalus (i.e. Pterodactylus), with a distinctive long tail. He named it Ornithocephalus longicaudus, meaning "long tail", to differentiate it from the specimens with short tails (the true specimens of Pterodactylus).

In 1845, Hermann von Meyer officially emended the original species Ornithocephalus münsteri to Pterodactylus münsteri, since the name Pterodactylus had been by that point recognized as having priority over Ornithocephalus. In a subsequent 1846 paper describing a new species of long-tailed 'pterodactyl', von Meyer decided that the long-tailed forms of Pterodactylus were different enough from the short-tailed forms to warrant placement in a subgenus, and he named his new species Pterodactylus (Rhamphorhynchus) gemmingi after a specimen owned by collector Captain Carl Eming von Gemming that was later by von Gemming sold for three hundred guilders to the Teylers Museum in Haarlem. It was not until 1847 that von Meyer elevated Rhamphorhynchus to a full-fledged genus, and officially included in it both long-tailed species of Pterodactylus known at the time, R. longicaudus (the original species preserving a long tail) and R. gemmingi. The type species of Rhamphorhynchus is R. longicaudus; its type specimen or holotype also was sold to the Teylers Museum, where it still resides as TM 6924.

The original species, Pterodactylus münsteri, remained misclassified until a re-evaluation was published by Richard Owen in an 1861 book, in which he renamed it as Rhamphorhynchus münsteri. The type specimen of R. muensteri, described by Münster and Goldfuss, was lost during World War II. If available, a new specimen, or neotype, is designated as the type specimen if the original is lost or deemed too poorly preserved. Peter Wellnhofer declined to designate a neotype in his 1975 review of the genus, because a number of high-quality casts of the original specimen were still available in museum collections. These can serve as plastotypes.

By the 1990s (and following Wellnhofer's consolidation of many previously named species), about five species of Rhamphorhynchus were recognized from the Solnhofen limestone of Germany, with a few others having been named from Africa, Spain, and the UK based on fragmentary remains. Most of the Solnhofen species were differentiated based on their relative size, and size-related features, such as the relative length of the skull.

In 1995, pterosaur researcher Chris Bennett published an extensive review of the currently recognized German species. Bennett concluded that all the supposedly distinct German species were actually different year-classes of a single species, R. muensteri, representing distinct age groups, with the smaller species being juveniles and the larger adults. Bennett's paper did not cover the British and African species, though he suggested that these should be considered indeterminate members of the family Rhamphorhynchidae and not necessarily species of Rhamphorhynchus itself. Despite the reduction of the genus to a single species, the type species remains R. longicaudus.

In 2015, a new species of Rhamphorhynchus, R. etchesi was named for associated remains of a left and right wing from the Kimmeridge Clay in the United Kingdom, the name commemorates the discoverer, Steve Etches, a local collector of the fossils of the Kimmeridge Clay. It is distinguished from other species of Rhamphorhynchus by "the unique length ratio between wing phalanx 1 and wing phalanx 2"

Phylogeny
The cladogram of below is the result of a large phylogenetic analysis published by Brian Andres & Timothy Myers in 2013. The species R. muensteri was recovered within the family Rhamphorhynchidae, sister taxon to both Cacibupteryx and Nesodactylus.

Description

The largest known specimen of Rhamphorhynchus muensteri (catalog number BMNH 37002) measures  long with a wingspan of . A very large, fragmentary rhamphorhynchid specimen from Ettling in Germany may also belong to the genus, in which case Rhamphorhynchus would be the largest known non-pterodactyloid pterosaur and one of the largest pterosaurs known from the Jurassic. This specimen represents an individual around 180% the size of the next largest specimen of the genus, with an estimated wingspan of over 3 metres.

Skull
Contrary to a 1927 report by pterosaur researcher Ferdinand Broili, Rhamphorhynchus lacked any bony or soft tissue crest, as seen in several species of contemporary small pterodactyloid pterosaurs. Broili claimed to have found a two-millimeter-tall crest made of thin bone that ran much of the skull's length in one Rhamphorhynchus specimen, evidenced by an impression in the surrounding rock and a few small fragments of the crest itself. However, subsequent examination of this specimen by Wellnhofer in 1975 and Bennett in 2002 using both visible and ultraviolet light found no trace of a crest; both concluded that Broili was mistaken. The supposed crest, they concluded, was simply an artifact of preservation. The teeth of Rhamphorhynchus intermesh when the jaw is closed and are suggestive of a piscivorous diet. There are twenty teeth in the upper jaws and fourteen in the lower jaws.

Paleobiology

Life history

Traditionally, the large size variation between specimens of Rhamphorhynchus has been taken to represent species variation. However, in a 1995 paper, Bennett argued that these "species" actually represent year-classes of a single species, Rhamphorhynchus muensteri, from flaplings to adults. Following from this interpretation, Bennett found several notable changes that occurred in R. muensteri as the animal aged.

Juvenile Rhamphorhynchus had relatively short skulls with large eyes, and the toothless beak-like tips of the jaws were shorter in juveniles than adults, with rounded, blunt lower jaw tips eventually becoming slender and pointed as the animals grew. Adult Rhamphorhynchus also developed a strong upward "hook" at the end of the lower jaw. The number of teeth remained constant from juvenile to adult, though the teeth became relatively shorter and stockier as the animals grew, possibly to accommodate larger and more powerful prey. The pelvic and pectoral girdles fused as the animals aged, with full pectoral fusion attained by one year of age.

The shape of the tail vane also changed across various age classes of Rhamphorhynchus. In juveniles, the vane was shallow relative to the tail and roughly oval, or "lancet-shaped". As growth progressed, the tail vane became diamond-shaped, and finally triangular in the largest individuals.

The smallest known Rhamphorhynchus specimen has a wingspan of only ; however, it is likely that even such a small individual was capable of flight. Bennett examined two possibilities for hatchlings: that they were altricial, requiring some period of parental care before leaving the nest, or that they were precocial, hatching with sufficient size and ability for flight. If precocious, Bennett suggested that clutches would be small, with only one or two eggs laid per clutch, to compensate for the relatively large size of the hatchings. Bennett did not speculate on which possibility was more likely, though the discovery of a pterosaur embryo (Avgodectes) with strongly ossified bones suggests that pterosaurs in general were precocial, able to fly soon after hatching with minimal parental care. This theory was contested by a histological study of Rhamphorhynchus that showed the initial rapid growth was followed by a prolonged period of slow growth.

In 2020, published ontogenetic analyses indicated that Rhamphorhynchus could fly soon after hatching, supporting the theory of precociality in the species. It has also been suggested that juveniles may have occupied different sequential niches throughout their growth as they matured.

Metabolism

Having determined that Rhamphorhynchus specimens fit into discrete year-classes, Bennett was able to estimate the growth rate during one year by comparing the size of one-year-old specimens with two-year-old specimens. He found that the average growth rate during the first year of life for Rhamphorhynchus was 130% to 173%, slightly faster than the growth rate in alligators. Growth likely slowed considerably after sexual maturity, so it would have taken more than three years to attain maximum adult size.

This growth rate is much slower than the rate seen in large pterodactyloid pterosaurs, such as Pteranodon, which attained near-adult size within the first year of life. Additionally, pterodactyloids had determinate growth, meaning that the animals reached a fixed maximum adult size and stopped growing. Previous assumptions of rapid growth rate in rhamphorhynchoids were based on the assumption that they needed to be warm-blooded to sustain active flight. Warm-blooded animals, like modern birds and bats, normally show rapid growth to adult size and determinate growth. Because there is no evidence for either in Rhamphorhynchus, Bennett considered his findings consistent with an ectothermic metabolism, though he recommended more studies needed to be done. Cold-blooded Rhamphorhynchus, Bennett suggested, may have basked in the sun or worked their muscles to accumulate enough energy for bouts of flight, and cooled to ambient temperature when not active to save energy, like modern reptiles.

Swimming

Though Rhamphorhynchus is often depicted as an aerial piscivore, recent evidence suggests that, much like most modern aquatic birds, it probably foraged while swimming. Like several pteranodontians it has hatchet-shaped deltopectoral crests, a short torso and short legs, all features associated with water based launching in pterosaurs. Its feet are broad and large, being useful for propulsion, and the predicted floating position is adequate by pterosaur standards. The animal's ability to swim may account for the genus' generally excellent fossil record, being in a position where preservation would be much easier.

Sexual dimorphism
Both Koh Ting-Pong and Peter Wellnhofer recognized two distinct groups among adult Rhamphorhynchus muensteri, differentiated by the proportions of the neck, wing, and hind limbs, but particularly in the ratio of skull to humerus length. Both researchers noted that these two groups of specimens were found in roughly a 1:1 ratio, and interpreted them as different sexes. Bennett tested for sexual dimorphism in Rhamphorhynchus by using a statistical analysis, and found that the specimens did indeed group together into small-headed and large-headed sets. However, without any known variation in the actual form of the bones or soft tissue (morphological differences), he found the case for sexual dimorphism inconclusive.

Head orientation

In 2003, a team of researchers led by Lawrence Witmer studied the brain anatomy of several types of pterosaurs, including Rhamphorhynchus muensteri, using endocasts of the brain they retrieved by performing CAT scans of fossil skulls. Using comparisons to modern animals, they were able to estimate various physical attributes of pterosaurs, including relative head orientation during flight and coordination of the wing membrane muscles. Witmer and his team found that Rhamphorhynchus held its head parallel to the ground due to the orientation of the osseous labyrinth of the inner ear, which helps animals detect balance. In contrast, pterodactyloid pterosaurs, such as Anhanguera, appear to have normally held their heads at a downward angle, both in flight and while on the ground.

Daily activity patterns
Comparisons between the scleral rings of Rhamphorhynchus and modern birds and reptiles suggest that it may have been nocturnal, and may have had activity patterns similar to those of modern nocturnal seabirds. This may also indicate niche partitioning with contemporary pterosaurs inferred to be diurnal, such as Scaphognathus and Pterodactylus.

Ecology

Several limestone slabs have been discovered in which fossils of Rhamphorhynchus are found in close association with the ganoid fish Aspidorhynchus. In one of these specimens, the jaws of an Aspidorhynchus pass through the wings of the Rhamphorhynchus specimen. The Rhamphorhynchus also has the remains of a small fish, possibly Leptolepides, in its throat. This slab, cataloged as WDC CSG 255, may represent two levels of predation; one by Rhamphorhynchus and one by Aspidorhynchus. In a 2012 description of WDC CSG 255, researchers proposed that the Rhamphorhynchus individual had just caught a Leptolepides while it was swimming. As the Leptolepides was travelling down its pharynx, a large Aspidorhynchus would have attacked from below the water, accidentally puncturing the left wing membrane of the Rhamphorhynchus with its sharp rostrum in the process. The teeth in its snout were ensnared in the fibrous tissue of the wing membrane, and as the fish thrashed to release itself the left wing of Rhamphorhynchus was pulled backward into the distorted position seen in the fossil. The encounter resulted in the death of both individuals, most likely because the two animals sank into an anoxic layer in the water body, depriving the fish of oxygen. The two may have been preserved together as the weight of the head of Aspidorhynchus held down the much lighter body of Rhamphorhynchus.

"Odontorhynchus"
"Odontorhynchus" aculeatus was based on a skull with lower jaws that is now lost. This set of jaws supposedly differed in having two teeth united at the tip of the lower jaw, and none at the tip of the upper jaw. The skull was , making it a small form. Stolley, who described the specimen in 1936, argued that R. longicaudus also should be reclassified in the genus "Odontorhynchus". Both Koh and Wellnhofer rejected this idea, arguing instead that "Odontorhynchus" was a junior synonym of R. longicaudus. Bennett agreed with their assessments, and included both "Odontorhynchus" and R. longicaudus as synonyms of R. muensteri.

See also

 List of pterosaur genera
 Timeline of pterosaur research

References

Late Jurassic pterosaurs of Europe
Jurassic reptiles of Africa
Rhamphorhynchids
Solnhofen fauna
Fossil taxa described in 1846
Taxa named by Christian Erich Hermann von Meyer

Rhamphorhynchus


La cinasa de la cadena ligera de la miosina o quinasa de la cadena ligera de la miosina (MYLK o MLCK) () es una enzima perteneciente a las serina/treonina proteína cinasa que cataliza la reacción:

 [Cadena ligera de la miosina] + ATP  [Cadena ligera de la miosina] + ADP + P

Esta enzima necesita como cofactor calcio y para ser activa necesita calmodulina. La cadena ligera de 20 kDa de la miosina del músculo liso es fosforilada más rápido que cualquier otro aceptor, pero las cadenas ligeras de otras miosinas y la propia miosina pueden actuar también como aceptores con una menor velocidad de reacción.

Se conocen cuatro isozimas de la cinasa de la cadena ligera de la miosina: MYLK, MYLK2, MYLK3 y MYLK4.

Cinasa de la cadena ligera de la miosina, isoenzima 1 (MYLK)

Esta enzima dependiente de calcio/calmodulina es codificada por el gen MYLK y está implicada en la contracción del músculo liso vía la fosforilación de las cadenas ligeras de miosina. También regula la interacción actina-miosina a través de una actividad no cinasa. Está implicada en la regulación de la permeabilidad endotelial y vascular. En el sistema nervioso se ha observado que controla el inicio de los procesos astrocíticos y que participa en la liberación de transmisores en las sinapsis formadas entre células simpatéticas de ganglios nerviosos. Es un participante crítico en las secuencias de señalización de la apoptosis de los fibroblastos.

Como cofactor también puede utilizar magnesio. La isoforma 1 (telokina) es activada por fosforilación en los residuos Tyr-464 y Tyr-471. Las isoformas que no tienen estos residuos tirosina no se regulan de esta forma. Interacciona con la supervilina.

Las isozimas musculares y no musculares son expresadas en una amplia variedad de tejidos adultos y fetales. La isoforma 2 no-muscular es la variante dominante en varios tejidos. La MLYK es probablemente regulada negativamente por fosforilación. El C-terminal de la proteína nativa es deglutamilada por AGTPBP1/CCP1, AGBL1/CCP4 y AGBL4/CCP6 para formar la cinasa de la cadena ligera de la miosina.

Los defectos en MYLK son causa del aneurisma aórtico torácico de tipo 7 (AAT7). Es una enfermedad caracterizada por una dilatación permanente de la aorta torácica debido usualmente a cambios degenerativos en la pared aórtica. Está asociada principalmente con una apariencia histólogica característica conocida como necrosis medial o necrosis medial cística de Erdheim en la que hay una degeneración y fragmentación de fibras elásticas, pérdida de células musculares lisas y una acumulación de sustancias basofílicas.

Cinasa de la cadena ligera de la miosina, isoenzima 2 (MYLK2)

La MYLK2 está implicada en la contracción muscular global y en la función cardiaca. Fosforila un residuo específico de serina en el N-terminal de la miosina de cadena ligera. Puede interaccionar con la centrina. Su localización celular es el citoplasma. Se colocaliza con la cinasa de la cadena ligera de la miosina fosforilada en los filamentos de las miofibrillas. Se expresa en los músculos cardiacos y esquelético. Su expresión está incrementada en el tejido apical en comparación con el tejido septal.

Los defectos en MYLK2 son causa de cardiomiopatía hipertrófica (CMH). Es un desorden hereditario del corazón caracterizado por hipertrofia ventricular que usualmente es asimétrica y que frecuentemente involucra al septum interventricular. Los síntomas incluyen disnea, síncope, colapso, palpitaciones y dolor de pecho. Estos síntomas pueden ser fácilmente provocados por el ejercicio. El desorden tiene variabilidad inter e intrafamiliar desde la forma benigna a la maligna con alto riesgo de fallo cardiaco y muerte cardiaca súbita.

Referencias

Serina/treonina proteína cinasas