Showing Revision 1 created 09/30/2015 by Jenny Luo.

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   ♪ (music playing) ♪

   ¶

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   There were three females of
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   brown banded bamboo sharks
   here at the academy
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   and they were acquired in 2007
   from the Aquarium of the Pacific.
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   And what happened is that one
   of those females
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   actually produced one egg that
   started developing normally.
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   There were no males here.
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    And in Janurary 2012, that pup was born.
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    At first, we thought that this
    was a case of parthenogenesis.
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    Parthenogenesis is known in
    popular literature as virgin birth.

    ¶

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    And what happens in parthenogenesis
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    is that there's one unfertilized egg
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    that actually starts developing normally
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    until it becomes a pup.
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    Parthenogenesis is actually
    really common in the natural world
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    but when we did
    the genetic testing,
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    what we did is that we
    compared the three females
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    with that pup and we actually
    found that the pup was
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    the most dissimilar
    organism of the three.
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    He was so, so dissimilar that we couldn't even tell
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    which of the females was the mother.
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    And we think that that genetic
    information actually came from a father.
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    That's where the story
    gets really interesting
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    because what we think happened is that
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    the female actually stored sperm
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    from one of the males at the Aquarium of the Pacific
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    for a really long period of time.
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    Actually, sperm storage is not a well-known strategy
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    but it's fairly common for insects.
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    And in the case of vertebrates,
    it happens very often in snakes.
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    And this is really exciting because
    what we think happened
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    is that one female stored
    sperm for 45 months
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    and that's the longest amount of time
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    that we know any shark storing sperm.
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    So those two strategies are
    actually found in solitary species
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    in which encounters between
    males and females
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    are actually very rare.
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    In the case of sharks,
    there's a lot of questions
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    about conservation when we touch
    this topic of parthenogenesis
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    and sperm storage.
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    And the reason behind this is that
    with dwindling shark populations,
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    encounters between males and females
    may actually become
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    even more rare.
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    And in those cases, a lot of scientists
    think that parthenogenesis
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    might become more common.
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    If parthenogenesis becomes more common,
    you may have a population
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    with several individuals
    but all those individuals
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    are gonna be
    very, very similar to each other.
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    That means that genetic diversity
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    is actually going to be
    very, very reduced.
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    So a sperm storage is actually a
    strategy that allows that maintenance
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    of that healthy genetic diversity
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    that's going to help sharks
    be here on planet earth
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    for many more years to come.
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    ♪ (music playing) ♪