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Every day, around
350,000 babies are born.
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Each one, utterly unique.
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A few months ago,
this baby didn't even exist.
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And the story of how it came to be
against impossible odds is extraordinary.
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This is the moment of conception.
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When one single sperm
fused with the mother's egg.
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If another sperm got there first,
this baby would be someone else.
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So what made that winning sperm so special?
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Why did it succeed over billions of others?
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To find out, we're going to take you on the epic
journey sperm undertake through the human body.
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And we're going to do it by scaling
the whole thing up to human size.
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For the first time we'll be able to appreciate
just what an extraordinary journey sperm face
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as they try to reach the egg.
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It's one of nature's
most spectacular stories
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and it's the reason you're alive.
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The sperm will face death at every turn.
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There is no going back.
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No surrender.
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And only one winner!
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Meet Glenn.
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Like most average men,
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Glenn has no idea about
the miracle of engineering,
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tucked away in his pants.
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Glenn's testicles, hanging freely to be 3
degrees cooler than the rest of his body
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are producing a thousand
sperm with every heart beat.
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And it's this tiny world of phrenetic activity that
fascinates the world of reproductive science.
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Sperm are really quite unique because
they're almost like free living cells,
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they almost have a life of their own.
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They have but one aim
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which is to deliver a genetic
payload from the male to the female,
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through a really quite
complex series of environments,
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both in the male and in the
female reproductive tracts.
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Sperm move all over the place
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and they like certain things,
they don't like certain things
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they're very smart little creatures in a way
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and they're a lot of fun to watch
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in the petri dish because
they're constantly in motion.
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And the fact that it's occurring
at the microscopic level
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means that as scientists we have a great
deal of difficulty in studying it and observing it.
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A sperm is just one five hundredth
of a million millimetre long,
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so to make things easier,
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Dr. Allan Pacey and the team of experts
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have agreed to help us scale up them
and their world thirty four thousand times.
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Along the way, they'll
give us practical advice
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on how to give sperm the
best chance of reaching the egg,
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or what kind of sex to
have and when to have it
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to maximise the chances of conception.
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The first thing we asked
our experts was quite simple,
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in our people sized sperm world,
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what would a testicle be like?
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The testicle is a, is a roundish
kind of oblong structure,
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if we cut it in half, we
cut thin layers through it
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and looked at it down a microscope
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we would see a series of tubules that
you might liken to floors of a building.
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If we were to take a sperm
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and scale it up to man's size
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you would have to find a building that
was about a thousand metres cubed,
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a thousand metres, by a thousand
metres, by a thousand metres.
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That done, we can go inside.
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Waiting in our giant testicle,
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an army of freshly created sperm.
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Just like the real thing,
our sperm are split by gender.
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Half produce boys and half produce girls.
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The information needed to
determine the sex of a baby,
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is stored in the sperm's head.
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Here, we find our genetic package,
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23 chromosomes of DNA
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including the key gender chromosome,
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either x for a girl or y for a boy.
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Situated just below the head,
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an engine of energy producing mitochondria
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that propels the sperm's mighty
tail through the female body.
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There's many millions of sperm,
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you could think of that as a
very, very large office building,
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where there's lots and lots of elevators
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and tonnes of people maybe at rush
hour all moving in different directions.
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x and y sperm are produced
in almost equal numbers,
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boys are thought to be faster
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but the girls live longer.
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Once created, each sperm
ends up in a structure
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on top of the testicle cord
called the epididymis.
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A tightly coiled 6 metre long tube.
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Which can hold over a billion sperm.
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Imagine, being crammed into a dark,
winding 200 mile pipeline with no idea
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when or if you'll ever get out.
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It's here, with no inkling
of the horrors to come.
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Our sperm must wait.
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Their fate, now,
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will depend on events
unfolding in the outside world.
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In contrast to the billions of sperm
produced continuously in Glenn's body.
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A woman, like Emily will
produce just one egg per month.
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Reaching it won't be easy.
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The battle that sperm have
in order to find and fertilise an egg,
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is just immense, everything
is working against sperm.
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um, they're not really given a helping
hand by the female reproductive tract.
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You've got, hundreds of millions of cells
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that are swimming wildly about.
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You've got a lot of death,
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you've got a lot of obstacles to overcome.
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They've got to make their way through
a complex series of environments
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in a, in a kind of warfare, it is warfare.
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So if conception is a war,
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this is the theatre of operations.
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From a sperm's point of view
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landing in Emily's vagina is like D-Day.
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Their first objective, whilst under non stop
attack from the female immune system,
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is to reach a tiny opening high
above them at the back of the vagina,
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from here, they can enter the cervix.
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The terrain in the cervix
is completely different,
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this, is a dark treacherous
maze of unchartered tunnels.
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The sperm will need to find
a way through to the uterus.
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One wrong turn and
it's a slow, lonely death.
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In the uterus,
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Glenn's sperm will be looking for a
doorway just a few sperm head wide
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in a vast, sterile area, where once again
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Emily's elite defence force
will be waiting to take them out.
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Then it's on to meet the egg,
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timing is everything,
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get there a moment too early or too late
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and your doomed.
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[Lady's laughter]
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Emily,
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Emily,
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Emily.
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[Muffled singing]
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Glenn's sperm are just seconds
away from participating in
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one of the most enjoyable experiences
the human body has to offer.
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But what would it feel like, to
be propelled along a narrow pipe
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covering 50 miles in less than
2 seconds whether you like it or not.
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[Dramatic music]
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For each individual sperm, this is a wet and
wild high speed one way ticket to oblivion.
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aaarrrrgggghhhh!!
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They're not swimming, they're being
forced there by muscular contractions
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and by peristaltic contractions.
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From the point of view from the man,
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it's a very pleasurable experience.
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But let's think about it from
the point of view of the sperm.
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250 million genetic couriers
are about to invade Emily's body.
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Within minutes, most of them will be dead.
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Millions of Glenn's sperm
have just entered Emily.
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They're embarking on an epic
quest to find and fertilise and egg.
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aaarrrrgggghhhh!!
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There can be only one winner,
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but what chance does an average
sperm have of succeeding?
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And is there anything Glenn
can do to help his sperm along?
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To find out,
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we need to look more closely
at the state of our seed.
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A ritual men like Dr. Allan Pacey
have performed on themselves
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since the invention of the microscope
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I was in my mid twenties and I was a
researcher before I plucked up the courage to
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produce a sample of my own semen
and have a look down the microscope
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and I remember the first time
looking down a microscope
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and I was just blown away,
I almost fell off my chair.
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I remember having to stand up and walk
around the lab and go back and look down the
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microscope again and is that, has that really
come from me, it was just an incredible sight.
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The incredible sight of the sperm cell
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was officially discovered in 1677 by a
Dutchman called Antonie van Leeuwenhoek.
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The godfather of microbiology, Leeuwenhoek
built some of the earliest microscopes.
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Offering him the first, if slightly unclear,
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image of what he called animalcules
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which he theorised contained
the nucleus of a human
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and had a tail equipped with
joints, tendons and muscles
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Later, other early microbiologists believed
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they could see tiny fully formed
people stuffed into each sperm head.
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Modern scientists of course
have a much clearer view.
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But they might wish they didn't.
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Because thanks to the quantity over quality
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nature of sperm production, a long hard
look at an average ejaculate today gives
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us the first clues as to why
men need so many sperm.
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Of the many millions of
sperm that are ejaculated
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we've got a huge range of different types
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if we were to look at them
down the microscope
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you'd see some sperm that were
really just hardly moving at all
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just twitching or some
sperm that would appear dead
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and may well indeed be dead.
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If you looked at their shape, you
would see sperm with large heads
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you would see sperm with small heads
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you may see sperm two heads.
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In an average fertile man that only,
18, 19, 20 per cent maximum of his sperm
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will have a nice size and shape,
but the rest, the other 80 per cent
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really aren't going
to get anywhere at all.
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To succeed in the race,
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sperm must be as fresh
and numerous as possible
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any old ones won't make
it past the starting blocks
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and as they decay they release substances
that can actually harm younger sperm.
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What is inappropriate, is the fact that
the man may be denied by his wife from
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ejaculating for 3 weeks
prior to the fertile window in
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this um, bizarre thought that
they're going to be super sperm
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and huge numbers of them,
that would be the wrong thing to do.
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So is the right thing to do, to ejaculate
as often as possible? apparently not.
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If a man is ejaculating too frequently
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then the sperm production process and the
sperm stores simply won't contain enough sperm
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So, just how regularly should a couple have
sex to make sure his sperm are match fit?
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If a couple is having intercourse every
2 or 3 days throughout the month,
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then they will hit the fertile window at some
point and their probability of conception
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is probably as good as it could be.
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Now, ready or not
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Glenn's sperm begin their quest
for conception in the vagina.
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Their objective, to find the entrance to the cervix,
high above them, at the vagina's farthest reaches
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From the perspective of a sperm the
vagina is like a vast mountain range.
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It's an enormous and awe-inspiring place
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Five miles deep and two miles wide,
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flanked with vast vaginal walls up to one mile high.
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Leaving the thick semen armour
that protected them for landing
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it's time for Glenn's sperm
to make a break for the cervix.
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The great advance has begun.
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But it's not just the
epic terrain in the vagina
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or even their own physical failings that
now pose a mortal threat to sperm.
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Everything in the vagina is
working against sperm survival
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there's only a matter of minutes
between sperms arrival and potential death.
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Sperm face attack from every angle,
the use of intimate lubricants
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and even saliva here can render
sperm lifeless in minutes
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Worst of all, thanks to the female immune
system, the vagina is coated with deadly acid.
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The acid is there to kill and invading force,
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I think that's a really important point to recognise
because as far as the female is concerned
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sperm are an invading force, they're foreign cells,
they could be there to cause damage
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they could be there to spread infections,
they are foreign cells to her
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and as far as her immune system is
concerned they need to be destroyed.
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Within 30 minutes of entering the vagina, over
99 per cent of sperm will be dead or dying.
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For our sperm people, it would
be a scene of devastation.
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A few million survivors press on
into the dark side of the vagina.
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Desperate to somehow escape death by
reaching the cervix high above them.
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But the entrance is out of reach,
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now to avoid total annihilation,
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Emily's body needs to come to the rescue.
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To understand how, meet Zita West
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Zita is a mid-wife who specialises in helping
couples conceive using natural methods.
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And she knows the odds of any sperm
making it past the vagina are slim at best.
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For most of the month these
sperm aren't going anywhere
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you know, the female body isn't allowing them to.
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Her cervix will be shut and there'll be a plug of mucous
there that's stopping any sperm getting through.
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But there will be an opportunity when a lifeline is given
to enable the sperm to actually reach the egg.
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And that lifeline is the egg itself.
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The cervix is usually sealed to protect the
inside of the body from anything nasty.
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But as ovulation approaches
oestrogen surges through the female body
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causing the body's mucous to
undergo a radical transformation.
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So this is what the sperm will be hoping for.
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It's the same consistency as cervical secretions.
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And these secretions will be coming
from the cervix into the vagina
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forming channels for the sperm to be able to swim up.
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Now these secretions are alkaline
and they contain salts and sugars
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which will nourish the sperm and
give them energy on their journey.
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This is the first sort of fitness
test if you like for the sperm
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not all the sperm will be able to swim up here, it'll depend
on the healthiest, the fittest, the fastest swimmers,
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some that are more abnormal
in the shapes of their heads etc.
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won't be able to fit in these channels
to be able to swim up as easily.
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Back in our people sized sperm world,
what would this fitness test compare to?
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Well, what if your life depended on climbing a ladder?
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A ladder stretching over a mile into the sky.
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It's a long gravity defying climb that only
a tiny fraction of sperm will be able to manage.
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For the 60,000 or so that do, it's out
of the frying pan and into the fire.
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Now they must endure stage 2 of their quest, the cervix.
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The objective here, to push 4cm to the other side
and reach the wide open space of the uterus.
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Sounds simple, until we take a closer look at the terrain.
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The cervix is quite simply, sperm hell.
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It's lined with tens of thousands of tiny
branching tunnels most roads to nowhere
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and some just a single sperm head wide.
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With the vast majority, if not all of Glenn's sperm will
get crushed, trapped and ultimately face a slow death.
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Nature does have a selection process in the cervix,
it is selecting sperm that are well made.
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It would be a bit like me dressed as a sperm,
trying to climb a staircase that's a kilometre high.
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I'm defying gravity, I'm going against
the flow and when I get to the top
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I find that I've gone down the wrong staircase
and I should have gone down another one
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Our sperm must fight their way,
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crushed amongst thousands of others up through
a twisted nightmarish urban environment
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Only one per cent of sperm that make it into the
cervix have any chance of making it out alive.
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But could the performance of Glenn's sperm be
affected by his performance between the sheets?
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This woman thinks so
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As Dr Joanna Ellington knows
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an average fertile healthy couple has just a
one in five chance of conceiving every month.
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And for her, success depends on
the quality of the sex they're having.
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The better the sex, the better your chance of conception.
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One of the things a lot of men don't realise
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is that the more excited they are
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the further back in the testicle
they're going to draw on reserves,
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so if you have, what I like to call 'gourmet sex'
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where you really spend time and you
really make it fun for both partners
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that is going to make the man more excited, more
stimulated and he's going to ejaculate more sperm
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and they're healthier sperm.
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Research shows that men enjoying 'gourmet sex'
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can ejaculate up to fifty per cent more sperm.
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Good news for Glenn, but what about Emily?
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Could more fun in bed for her
help the chances of conception?
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Nineteen century evolutionary psychologists believed
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'the purpose of female organisms was to
keep a woman lying down longer after sex
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keeping sperm in the body and
increasing her probability of conception.'
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More recently its been suggested the female orgasm
evolved to create a stronger bond between lovers
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increasing the chances of the couple
staying together after a child is born.
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Nice theories,
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but there's never been any actual
evidence to support the idea
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that female orgasm had any functional
relevance what so ever, until now.
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I happen to be a fan of female orgasm myself, and that's
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from a physiological stand point
as well as the personal one.
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What happens during female orgasm is the
pH in the vagina actually is elevated some,
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there's some changes in the ion concentration
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and there are contractions that help
pull the sperm up into the female's body.
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Strangely this remarkable theory has been supported
by a Danish study into the sex lives of pigs.
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Creatures with reproductive systems
almost identical to ours.
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We don't know if a pigs having an orgasm or not
but we know that if we stimulate their clitoris
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when they do artificial insemination
we can increase pregnancy rates.
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Some people mistakenly think that female orgasm is bad
for conception and there's certainly no evidence of that
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in fact the evidence would suggest
that it's a good thing to have.
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Luckily for Glenn,
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three thousand of his sperm are both full
fit and manage to avoid getting lost.
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But as the female immune system
prepares to mobilise its elite assassins,
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the great sperm race is about to get even tougher.
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Inside an unsuspecting woman,
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the great sperm race is underway.
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Our army of sperm, unstoppable
by sheer force of numbers
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have fought their way through the
mountainous terrain of the vagina
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and squeezed through the tight
passage ways of the cervix.
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Getting this far has cost many lives,
now just three thousand sperm remain.
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The adventure continues,
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thanks largely due to the fact that Emily is ovulating.
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So is it a coincidence
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this couple had sex at the perfect moment during her most fertile and sperm friendly monthly period?
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This man doesn't think so.
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For evolutionary psychologist Geoffrey Miller
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nothing in the great sperm race happens by accident.
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The sperm didn't get there by chance the woman's
body and brain has arranged for it to be there.
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Its made choices, in its life and its mate search
and its discrimination between male partners
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and its sexual behaviour that
led to the sperm being there.
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Female choice runs evolution, largely
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Unlike men, who can produce
millions of sperm every day,
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women are born with all the eggs
they will ever have, about a million.
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By menopause that number has fallen to zero,
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making them the most important
commodity in the natural world.
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A fertile egg from a healthy and intelligent egg
donor costs about $30,000 on the open market.
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If you take the size of the egg that adds out to
about a thousand trillion dollars per pound.
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So even in strictly economic terms a fertile egg,
it's rare, it's special, it's valuable
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Each egg is made even more precious
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because one will appear for just a few days per month.
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Many female animals make the most
of ovulation by experiencing oestrous,
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where their physical appearance, scent and
behaviour will change to advertise their fertility.
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Geoffrey Miller believes woman do the same thing.
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It used to be thought that humans uniquely lost oestrous
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that human females don't go
into oestrous when they ovulate.
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That somehow we have this
pair bond that trumps oestrous,
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but in fact the new research is showing
human females do go through oestrous,
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it serves exactly the same functions
that it does for other mammals,
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all the same hormones all the same
psychology is still right there
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under the surface of human culture.
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So could women effectively go on heat every month?
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Could their reproductive systems be unconsciously
controlling their actions and men's responses?
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Miller believes so
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and to prove it he and his team at the university of New
Mexico have carried out some extraordinary research
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at a gentleman's club
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We know that lap dancers earnings fluctuate a lot,
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so it seemed like an ideal
set-up for being able to ask them,
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how much have you earned night by nightshift by shift?
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and to be able to track that in relation to
where they are in the menstrual cycle.
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And we thought that was a pretty cool way of,
of, quantifying female attractiveness to males
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The dancers provided Miller's team with information
about their earnings and menstrual cycles
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over a period of 300 work shifts.
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The equivalent of about 5,000 lap
dancers for their male customers.
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The results were surprisingly strong,
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I was amazed at how strong the effects were
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that the women in oestrous were earning about twice as
much as they were earning when they were mensturating.
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If your'e ovulating you're a lot more attractive to men,
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you're earning higher tips, you're
getting called over for more lap dances.
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Miller's research suggests a link between
female ovulation and attractiveness to men.
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But if women are unconsciously
controlling men's actions once a month,
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What actually happens?
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They're more sexually perceptive,
higher sex drive more interest in sex,
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they dress in more stylish and revealing clothing,
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their voice pitch gets more attractive to men,
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breasts become more symmetrical,
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um, the waist to hip ratio changes,
so the waist gets relatively thinner.
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There also changes in smell, so that the women's scent
will be become more attractive to men during oestrous.
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So with a little help from the unconscious power of
ovulation the great sperm race continues.
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Two hundred and fifty million of Glenn's
battling sperm entered the vagina.
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Just three thousand have made it through
the dark twisted hell of the cervix.
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Which now opens out into an
environment that is altogether different.
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Our sperm expert Dr. Allan Pacey knows,
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if you or I were a sperm entering
the uterus would be quite a sight.
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From a sperm's point of view the
uterus represents a vast plain
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across which they have to navigate and find at the other end
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actually quite a tiny opening that will lead
them through to the fallopian tubes.
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Scaled up to sperm people size the uterus
becomes a large area of open country side,
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two miles long and around half a mile wide.
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For our sperm finding the entrance to the fallopian tubes
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just a few sperm head wide is like
looking for a needle in a haystack.
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Once again it's ovulation to the rescue.
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Ovulation occurs on one side one month,
the other side another month.
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So on the times that the egg is going to
be ovulated from the ovary on the left,
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the uterus seems to preferentially
move material to the left hand side.
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So the sperm are probably carried to a large
degree by these muscular contractions
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and moved through the uterus relatively quickly.
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But on this journey nothing is ever that easy.
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Glenn's sperm are about to discover they're not alone.
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They're running straight into an ambush.
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The primary function of the uterus is of course to receive
the developing embryo should conception occur
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and to gestate the foetus throughout pregnancy.
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It's not really designed for sperm,
it's designed for something else
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it will almost certainly begin to contain leukocytes
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and the immune response will be
mounted to try and mop up sperm
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and to try and kill the sperm before
they get to the fallopian tubes
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Leukocytes are the assassins of the female body,
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blood cells commanded into
action by the immune system.
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Massing into the uterus in their
thousands with murderous intent.
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In comparison to sperm, leukocytes are quite large,
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they're big cells, they often hunt in
packs they will detect a sperm
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and many leukocytes will descend upon the sperm
and encapsulate it and dismantle it slowly.
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For the female body of course, lukocytes
are wonderful essential things,
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fighting disease and harmful foreign materials.
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But let's try to imagine them from the
perspective of a trespassing sperm.
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Once again Glenn's sperm face utter decimation,
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as thousands are killed by Emily's immune system.
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Just a few dozen lucky ones reach
the entrance to the fallopian tubes.
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Only to find that there is a strict door policy.
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Sperm have to display the
correct swimming characteristics
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in order to get through that uterotubal junction.
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And any sperm expressing a very random
form of motion is probably excluded.
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There's also potentially a molecular
recognition system there
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so only sperm that are expressing the right
molecules actually are allowed through.
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Sperm have faced death and
destruction in the uterine cavity,
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the leukocytes have been trying to,
ah, kill them along the way
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and only a lucky few in comparison to the
many millions that are ejaculated initially
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actually make it into the fallopian tubes
where finally they get to sperm heaven.
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Welcome to one of Emily's fallopian tubes.
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10cm of what can only be
described as paradise for sperm.
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The environment of the fallopian tube
is just very accommodating for sperm,
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it's what sperm have been aiming for and it's set-up to
try and maintain sperm health and they can have a rest.
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Its got nutrients for them, its got the right pH
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it has the right ion concentration and some of these
sperm will actually bind to the fallopian tube cells
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their membranes will become very closely associated
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so that the fallopian tube cells can pass
nutrients and sugar and protect those sperm.
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Scientists believe with no immune
system trying to kill them
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sperm can blissfully hang around in the
fallopian tubes for hours, even days
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but ultimately it's hard to know for sure.
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At the farthest reaches of the reproductive tract
the fallopian tubes are very difficult to study,
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so difficult in fact some scientists
are willing to extraordinary lengths.
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When I was done having children
I choose to have my tubes tied
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and I told my Dr. that I wanted to do an experiment
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where I had intercourse before I had the surgery
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and then she was to cut out that section of my
fallopian tubes where the sperm were stored
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so that I could look at them under the electron
microscope and count how many sperm were there.
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So it was pretty humorous actually because I'm
coming out of anaesthesia and I was like
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did you get it, did you get it?
cause no one had ever done this before.
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There were about twenty sperm
in my tubes, that we counted.
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Thanks to such dedication,
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we now have a clearer sense of what happens
during the final stage of the voyage to the egg.
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The sperms objective, to wait for the
egg to appear ahead of them
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find it, swim through its outer layer and be the
first to reach its inner core and seal victory.
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But how will they know when the egg
has been released from its follicle?
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We're just beginning to
understand that there is receptors
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that communicate between the egg and the sperm
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and the sperm smell the egg,
they're able to sense where that egg is
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and you can even see this some in the petri dish
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when you're doing in vitro fertilisation
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if you put an egg in there, boy those sperm just
right away they orient themselves towards that egg
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they're going right towards it, they're
not wandering aimlessly around the dish
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hoping to encounter it, it's not left up to chance,
they know what they want to go find.
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It's believed sperm wait in the fallopian tubes
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until they pick up an irresistible sense signal
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which intensifies as the egg draws near.
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One study has shown, the scent attracting the
sperm smells just like Lily of the Valley perfume.
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The egg basically lays out a
red carpet and asks the sperm
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this way, this is where you want to go,
this is the end of your journey.
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So instead of swimming backwards into the uterus
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they head straight up that fallopian tube, right to the egg
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and that's how that final step of the sperm race is won.
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Back in the scaled up world of our great sperm race
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an egg is finally released, making its way
towards one end of the fallopian tube.
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The finish line is tantalisingly close.
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And from here on in timing is everything.
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She has no idea, but Emily could be
just minutes away from being pregnant.
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Beating incredible odds, Glenn's sperm
have fought their way through her body
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and have reached one of her fallopian tubes
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where hopefully an egg will be waiting.
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Just single figures have made it this far,
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scaled up to people size, what happens next?
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Imagine an olympic freestyle swimming final,
where the winner gains immortality
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and the rest are killed.
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Scent signals released during ovulation
will make the sperm hyperactive
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giving them the ability to actually fertilise the egg,
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shedding layers of proteins,
in a process called capacitation.
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Up until now they have been
swimming in quite straight lines
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but now they're swimming becomes much more erratic.
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And that tail beat will give them power and propulsion
in order to get through the outer coat of the egg.
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All of a sudden they are a hundred per cent on target.
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They want to find that egg, they want to penetrate
that egg and it's a race for the finish.
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So once they capacitate,
sperm die within just a few hours,
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so it's a no going back.
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On the sperm people scale, the egg
drifts just a mile or so ahead.
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But as our reproductive scientists can testify
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the egg's 24 hour lifespan will present
the sperm with one final, fatal hurdle.
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What needs to be kept in mind
for this whole great sperm race
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is timing, timing, timing, timing
because the egg has a limited lifetime.
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What if the egg arrives a little earlier?, we want some
sperm to be able to capacitate relatively early.
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What if that egg comes, maybe a few
hours from now or another day?
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Well, you don't want all the sperm to be capacitated right
at the beginning because then they're going to die.
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Having arrived hours before the egg,
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these sperm reach the end of the line
falling into the abyss beyond the fallopian tubes.
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Behind them, just two heroic sperm remain,
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all that survives of a quarter of a billion.
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These two are y chromosome bearing male sperm
and an x chromosome female
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left Glenn's testicles 14 hours ago.
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They've endured an incredible journey
and against overwhelming odds
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they've got their timing, just right.
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At the farthest reaches of Emily's reproductive system
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the egg is waiting.
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If you or I were a sperm, the egg would soar
into the sky as high as Nelson's column.
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During the great sperm race, there's
been this great attrition of sperm
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from the point of ejaculation through to the fallopian tube.
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Actually at the site of fertilisation
when the egg is being fertilised
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there may only be one sperm,
there may be two or three,
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but only very few sperm are actually
fighting for that final prize.
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Eventually one sperm will hit the outer coat of the egg
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and this is it, this is the moment
that they've been waiting for.
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To secure victory, all this sperm has to
do now is find a way inside
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The sperm is carrying this, this genetic payload
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for delivery, but that genetic payload
has to be able to get into the egg.
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And the way that it gets into the egg
is the sperm literally blows its top.
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Above the head of the sperm, there's kind
of a bag of juices, a bag of enzymes
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that are really important at this stage
of the process
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by touching an egg that bag bursts and those enzymes
will facilitate the sperm and finally penetrating through,
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um the outer coat of the egg,
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The great sperm race has been won.
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The victorious male sperm is instantly devoured
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as Glenn's genetic information
merges with Emily's waiting DNA.
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So you get this elegant dance of male chromosomes
and female chromosomes coming together
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which will officially announce the fact that, that egg
is fertilised and that new life is being created
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and development of a new individual
has started.
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Just fourteen hours ago,
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hundreds of millions of sperm embarked on the
most incredible adventure in the natural world,
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an adventure that claimed all their lives.
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So what made that winning sperm special?
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Why did it succeed over billions of others?
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When you think about the odds that
any single one of us are here right now
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compared to the hundreds and millions of other
sperm that in that ejaculate that were left behind
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there could have been, a smarter offspring
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a handsome or more athletic, a better in every way
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ones that just didn't make it, because they either
weren't in the right place at the right time
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or you know they just didn't find their way
through the cervix or uterotubal junction
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or maybe they capacitated a little too
early before the egg got there
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or maybe they were a little too late to capacitate
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so there's just a lot of luck involved with it as
well as to which sperm actually is able to fertilise.
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Yet one unremarkable sperm,
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against odds of trillions to one did not die in vein,
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it has given its life to start an utterly unique new one.