http___www.telegram.hr_zivot_spanjolski-biolozi-su-se-malo-iznenadili-kad-su-shvatili-da-im-u-laboratoriju-raste-fetus-morskog-psa-s-dvije-glave__1.xml
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Someone found a double-headed shark and we’re all going to die No, this is not something out of a horror movie – it is very real. The first ever two-headed shark of its kind has been discovered by scientists in Spain. Surfer back riding the waves just three weeks after a shark bit off his leg The bizarre creature, spotted by researchers at the University of Malaga, has two heads with a mouth, two eyes, a brain and five gill openings on each side. But don’t worry, it won’t be washing up on a shore near you, because the embryo was, in fact, dead when it was discovered. Scientists spotted the creature during a study of 797 Galeus atlanticus embryos and it is believed to be the first of its kind for the species. Though there have been previous reports of mutant fish in blue sharks, this is said to be the first that is an oviparous shark, meaning it developed inside an egg. Great white shark breaks into diver’s cage in video that won’t help your phobia And experts say genetics, rather than environmental factors, are behind the deformity and are unsure whether the shark would ever survive in the wild. Professor Valentin Sans-Coma, the leader of the study, said: ‘As far as is known, our paper gives the first description of a two-headed shark embryo belonging to an oviparous species. ‘There was no known exposure of the embryos to teratogenic agents. On this basis, we consider that an intrinsic genetic disorder seems to be the most plausible cause of maldevelopment.’ What is the Galeus atlanticus? - The Galeus atlanticus is a shark that is also known as the Atlantic sawtail catshark. - It lives in a small section of the western Mediterranean at depths of over 2,329 feet - The sharks feed primarily on small fish and crustaceans. - They are not harmful to humans The embryos had been collected from the Mediterranean by the Spanish Institute of Oceanography between 2005 and 2011. MORE: Apparently the reason we’re all afraid of sharks is because of ominous background music They were then transferred to the Malaga-based laboratory where they were preserved in a tank filled with sea water. A report on the discovery, published in the Journal of Fish Biology, states: ‘There were two hearts, two oesophaguses, two stomachs, two livers, but a single intestine with a spiral valve. ‘On the single body, there were four anticipated dorsal fins, two anterior, right and left and two posterior, right and left. ‘The specimen possessed two pairs of pectoral fins, a pair of pelvic fins and one anal fin.’ The animal, which is identified by its slender body and dark patches along its back, is often caught accidentally by deepwater trawlers
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Biolozi španjolskog Sveučilišta Malaga otkrili su embrij morskoga psa s dvije glave, piše Vox. Biolozi su ovaj embrij otkrili tijekom istraživanja i sortiranja stotina embrija morskih pasa vrste Galeus atlanticus u svom laboratoriju kako bi otkrili na koji se način razvija njihov kardiovaskularni sustav. “Svaka glava imala je usta, dva oka, mozak i pet škržnih otvora sa svake strane”, naveli su autori u istraživanju objavljenom u Journal of Fish Biology. Dvije glave se spajaju u jedno tijelo unutar kojeg se nalaze “dva srca, dvije jetre, dva želuca i dva jednjaka”, dok morski pas dijeli crijeva, bubrege i reproduktivne organe. Prvi put otkriven embrij s dvije glave Ovo je prvi puta da su znanstvenici otkrili morskog psa s dvije glave kod vrste koja izliježe jaja, kao što je slučaj kod ove vrste, navodi se u istraživanju. Znanstvenici su prethodno na ovakve slučajeve nailazili samo kod morskih pasa koje na svijet donose žive mladunce. Čak i u tim slučajevima, radi se o vrlo rijetkoj pojavi: u znanstvenoj literaturi spominje se samo sedam sličnih primjera u kojima su otkrivene vrste morskih pasa s dvije glave, dok su dva od njih sedam pronađena u prirodi, ističe se u istraživanju. Znanstvenici su ovaj rijedak primjerak dvoglavog morskog psa, koji se razvijao u fetus, eutanizirali i očuvali ga u formalinu i alkoholu. Ne znaju bi li mogao doživjeti zrelost David Shiffman, biolog i autor u Hakai magazinu, rekao je kako nitko ne zna bi li ovaj morski pas s dvije glave mogao doživjeti svoju zrelost, a o tome je razgovarao s Michelle Heupel, znanstvenicom australskog Instituta za znanosti o moru. “Opstanak nakon rođenja bi se mogao dogoditi, no on bi živio jako kratko. Nejasno je koja bi glava od dvije otežavala plivanje i hvatanje plijena, i bi li zajednički unutarnji organi ispravno funkcionirali”, rekla je Heupel. Unatoč tome, Heupel je rekla da su takve malformacije jako rijetke i da nisu prijetnja u očuvanju pojedinih vrsta morskih pasa. Blizanci s dvije glave jako su rijetki kod bilo koje vrste kralježnjaka, uključujući i ljude. No, i dalje se nameće pitanje što uzrokuje spajanje fetusa morskih pasa, ističu znanstvenici, navodeći da u inkubatorskim tankovima nije bilo teratogena, supstanci koji mogu dovesti do stvaranja malformacija kod ploda.