-
Title:
-
Description:
-
-
There were three females of
-
brown banded bamboo sharks
here at the academy
-
and they were acquired in 2007
from the Aquarium of the Pacific.
-
And what happened is that one
of those females
-
actually produced one egg that
started developing normally.
-
There were no males here.
-
And in Janurary 2012, that pup was born.
-
At first, we thought that this
was a case of parthenogenesis.
-
Parthenogenesis is known in
popular literature as virgin birth.
¶
-
And what happens in parthenogenesis
-
is that there's one unfertilized egg
-
that actually starts developing normally
-
until it becomes a pup.
-
Parthenogenesis is actually
really common in the natural world
-
but when we did
the genetic testing,
-
what we did is that we
compared the three females
-
with that pup and we actually
found that the pup was
-
the most dissimilar
organism of the three.
-
He was so, so dissimilar that we couldn't even tell
-
which of the females was the mother.
-
And we think that that genetic
information actually came from a father.
-
That's where the story
gets really interesting
-
because what we think happened is that
-
the female actually stored sperm
-
from one of the males at the Aquarium of the Pacific
-
for a really long period of time.
-
Actually, sperm storage is not a well-known strategy
-
but it's fairly common for insects.
-
And in the case of vertebrates,
it happens very often in snakes.
-
And this is really exciting because
what we think happened
-
is that one female stored
sperm for 45 months
-
and that's the longest amount of time
-
that we know any shark storing sperm.
-
So those two strategies are
actually found in solitary species
-
in which encounters between
males and females
-
are actually very rare.
-
In the case of sharks,
there's a lot of questions
-
about conservation when we touch
this topic of parthenogenesis
-
and sperm storage.
-
And the reason behind this is that
with dwindling shark populations,
-
encounters between males and females
may actually become
-
even more rare.
-
And in those cases, a lot of scientists
think that parthenogenesis
-
might become more common.
-
If parthenogenesis becomes more common,
you may have a population
-
with several individuals
but all those individuals
-
are gonna be
very, very similar to each other.
-
That means that genetic diversity
-
is actually going to be
very, very reduced.
-
So a sperm storage is actually a
strategy that allows that maintenance
-
of that healthy genetic diversity
-
that's going to help sharks
be here on planet earth
-
for many more years to come.
-
♪ (music playing) ♪