# 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