Now, you may be thinking what is so special about that? Sharks having babies isn’t exactly unheard of… ![]() In 2016, the beautiful Leonie laid eggs and produced three pups (babies). Let me tell you a story about a zebra shark, called Leonie, at the Reef HQ Aquarium in Townsville, Australia. So what is so special about the zebra shark? At night, they actively hunt for molluscs, crustaceans, small fishes, and possibly sea snakes. This species is nocturnal and spend most of the day resting motionless on the sea floor. However, this shark got its name from the pattern of a juvenile zebra shark, as they consist of light vertical white stripes on a brown background. Adult zebra sharks are distinctive in appearance with five longitudinal ridges on their cylindrical body, the dorsal fin starting halfway the body, and a pattern of dark spots on a sandy coloured body. It is found throughout the tropical Indo-Pacific, coral reefs and sandy flats to a depth of about 60 meters (200ft). ![]() The unique reproduction mode has excited scientists as they expect it could offer clues to rebuild the declining population of these sharks.The zebra shark (Stegostoma fasciatum) is a species of carpet shark. This is good news as zebra sharks have been declared endangered species already. ![]() She said asexual reproduction may be a useful strategy to sustain the population and survive in extreme isolation. "This is an extreme form of inbreeding, and the fact that these animals can survive, at least for short periods of time, with this highly reduced genetic diversity really challenges the way that we think about reproduction," Dudgeon said. However, during the period of 2015-2016, it produced 41 eggs from where three pups hatched between February and April of 2016. In the zebra shark's case, it produced 47 eggs during 2014-2015 but no pups were hatched. The asexual reproduction in sharks takes place when the egg gets fertilized by a nearby cell called a polar body that carries the genetic material of the female. However, he pointed out it is still rare to see such transitions happening in the other direction.ĭudgeon mentioned cases of asexual reproduction in some females who had previous histories of sexual production and cited an eagle ray and a boa constrictor, which transited from sexual to asexual reproduction as females. "In species that are capable of both reproductive modes, there are quite a few observations of switches from asexual to sexual reproduction," noted Russell Bonduriansky from the University of New South Wales. ![]() The study has been published in Scientific Reports.Īccording to experts, a dual mode of reproduction depending upon circumstances has not been uncommon. The case is unique as it is the first documented case of a female shark moving to parthenogenesis after a stage of normal reproduction without male support.ĭuring the study, the researchers ruled out chances of Leonie storing sperm of her ex-partner for fertilizing the eggs after they duly tested the genetic composition of the pups that showed they had only DNA from their mother, confirming the asexual mode of conception. "We thought she could be storing sperm but when we tested the pups and the possible parent sharks using DNA fingerprinting, we found they only had cells from Leonie," said Dudgeon, who led the study and serves on the faculty of School of Biomedical Sciences. The rare birth incident kicked off the interest of Christine Dudgeon of the University of Queensland who started studying the case right away.
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