# briefing
DOING IT FOR HERSELF A female zebra shark in an Australian aquarium has stunned the scientific community by giving birth to three young , despite having been separated from her male partner for a number of years . The shark had previously had 24 pups in her 12 years at the aquarium , but was placed in a separate tank in 2012 .
It is well known that some vertebrate species have the ability to reproduce asexually . This has been observed in snakes , some sharks , and rays . However , this form of reproduction normally occurs in individuals that have never reproduced sexually before . The switch from sexual to asexual reproduction has , so far , only been observed twice , once in a boa constrictor and once in an eagle ray .
The team at the aquarium verified that the zebra shark had not somehow stored her partner ’ s sperm during the years of separation ; DNA tests showed that the pups were only carrying the mother ’ s genetic material .
This form of reproduction is not favoured in vertebrate species as it results in low genetic diversity , low adaptability , and limited resilience , but is believed to function as a temporary mechanism to continue the species until a male partner can be found .
2016 : THE YEAR OF MARINE PARKS Despite all the dizzying drama and despair thrown up by 2016 , it could also be considered to be the year that the world got serious about marine conservation ; some of the largest marine protected areas the planet has ever seen were declared in 2016 :
THE TUN MUSTAPHA PARK
Where : Sabah , Borneo , Malaysia
Size : Nearly 10,000 square kilometres , including more than 50 islands and islets
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PAPAHĀNAUMOKUĀKEA MARINE NATIONAL MONUMENT
Where : Hawaii , USA
Size : 1.5 million square kilometres ( expanded by more than 1 million square kilometres )
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MEXICAN CARIBBEAN BIOSPHERE RESERVE
Where : Quintana Roo , Mexico
Size : More than 57,000 square kilometres
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NORTHEAST CANYONS AND SEAMOUNTS MARINE NATIONAL MONUMENT
Where : Just over 200 kilometres off the coast of New England , USA , in the Atlantic
Size : More than 12,700 square kilometres
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ROSS SEA
Where : Antarctica
Size : 1.57 million square kilometres
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8 SDAA